WO2025199205A1

WO2025199205A1 - Photoresponsive compounds

Info

Publication number: WO2025199205A1
Application number: PCT/US2025/020522
Authority: WO
Inventors: Elias PICAZO; Cesar REYES; Hye Joon Lee
Original assignee: University of Southern California USC
Current assignee: University of Southern California USC
Priority date: 2024-03-19
Filing date: 2025-03-19
Publication date: 2025-09-25
Anticipated expiration: 2026-09-19

Abstract

The present disclosure provides photoresponsive compounds of Formula I. Processes for synthesis of the photoresponsive compounds, as well as methods of use of the photoresponsive compounds, are also provided.

Description

Attorney Docket No.11760-002WO1 PHOTORESPONSIVE COMPOUNDS CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of priority to United States Provisional Application No. 63/567,010, filed March 19, 2024, the disclosure of which is incorporated herein by reference in its entirety. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT This invention was made with government support under Grant No. R00GM140070 awarded by the National Institutes of Health. The Government has certain rights in the invention. BACKGROUND Since their discovery as photoresponsive materials in 2014, donor-acceptor Stenhouse adducts (DASAs) have emerged as a prominent class of photoswitches with the capacity to advance smart materials, phototherapy, and logic-gated systems, among other applications (FIG. 1A). Studies have elucidated the structure-property relationships and multi-state switching mechanism that lead to absorbance in the visible to near-IR region, negative photochromism, and significant volume and polarity changes upon switching. Adaptable DASA physical properties arise from their assembly (FIG. 1B), which introduces modularity in molecular structure (FIG. 1C). However, since furan substrates have been the only heterocycles to undergo aza-Piancatelli rearrangements, the backbone heteroatom has remained limited to hydroxy substitution. Second generation DASAs evaluated the donor compartment and expanded to include aromatic amine donors such as indoline (FIG. 1C). The extended conjugation provided by second generation donors decreases charge separation within the open isomer, resulting in faster switching kinetics and broader solvent compatibility. Third generation DASAs explored the acceptor compartment, and it was determined that stronger pull character leads to a bathochromic shift in absorption and better control over dark equilibria, allowing for over 95% open-to-closed isomerization upon irradiation. More recently, substitutions on the triene compartment were studied. Aryl and bromide substitutions resulted in bathochromic shifts that produced DASAs with absorptions in the near-IR region. Further, alkyl substitutions were shown to create steric interactions that encourage closed-to-open thermal reversion. The impact Attorney Docket No.11760-002WO1 of each molecular compartment on DASA physical properties and potential applications inspires a community-wide interest in discovering the contributions from the backbone heteroatom compartment. Interested in the switching mechanics, Feringa and coworkers synthesized a nonhydroxy triene derivative via Zincke salt formation followed by secondary amine addition and Knoevenagel condensation to investigate the backbone heteroatom effects. The nonhydroxy triene was found to isomerize more slowly than the DASA by approximately one order of magnitude. Further, the nonhydroxy triene underwent photoisomerization at either C2–C3 or C3–C4, as opposed to exclusive rotation about C2–C3 for the parent DASA (FIG. 1D). Computed potential energy curves for the cyclization step point towards an energetically forbidden pathway for the nonhydroxy triene. Together, these results highlight a key hydrogen bond between the backbone hydroxy group and the acceptor carbonyl, as well as stabilizing electronic effects on the triene backbone provided by the heteroatom. Pioneering furan rearrangements dating back to as early as 1850 on fufurals by Stenhouse, Honda, and Lewis & Mulquiney, furylcarbinols by Piancatelli and Read de Alaniz, and activated furans by Šafař and Read de Alaniz, have contributed to the synthesis of Stenhouse salt derivatives, a multitude of prostanoic acid natural products, and DASA molecular photoswitches. Despite their impact, each rearrangement variant has remained limited to furan cores, constraining products to oxygen-containing molecules. Specific to DASAs, only a hydroxy group has been achievable for the backbone heteroatom compartment due to the synthetic dependence on activated furans. Lalevée and Dumur demonstrated that parent pyrrole and thiophene derivatives that would introduce other heteroatom functionality fail to undergo ring opening. This observation is consistent with heterocycle aromatic stability where thiophene, pyrrole, and furan carry stabilization energies of 120 kJ/mol, 89 kJ/mol, and 66 kJ/mol, respectively. Parallels between the Piancatelli rearrangement and DAS synthesis start from nucleophilic amine addition onto the heterom-adjacent carbon of the heterocycle (FIG. 5). Proton transfer is followed by ring-opening, which results in the formation of the triene backbone. This triene is the isolable DASA product in its open form. Upon photoisomerization, the thermally stable, open isomer 1 transforms into a cyclopentenone moiety 1’ (FIG. 1A) through a conrotatory 4π-electrocyclization, likening the aza-Pancatelli process. Hence, open- form DASA synthesis relies on an interrupted aza-Piancatelli rearrangement, and the backbone hydroxy group is introduced from the use of a furan starting material. Attorney Docket No.11760-002WO1 There is a clear need for additional photoresponsive compounds with features that allow greater tuning of their photoswitching properties. This disclosure addresses this as well as other needs. SUMMARY The present disclosure provides photoresponsive compounds, processes for synthesizing said compounds, and methods of using said compounds. More particularly, the present disclosure provides donor-acceptor Stenhouse adducts (DASAs) with heteroatom substitutions that allow for further tunability of their photoswitching properties. In particular aspects, the photoresponsive compounds described herein successfully replace the hydroxyl group found on the triene moiety of previously described DASAs with other heteroatom-containing moieties, such as nitrogen- and sulfur-containing groups, allowing further tuning of the associated properties. In one aspect, a photoresponsive compound is provided of Formula I (I) wherein all variables are as Processes for synthesizing the photoresponsive compounds described herein are also provided. For example, in another aspect, a process is provided for preparing a photoresponsive compound of Formula I, . In some aspects, the reacting a compound of Formula II Attorney Docket No.11760-002WO1 R1 with a donor D-H to form the I; wherein all variables are as further defined herein. Methods of using the photoresponsive compounds described herein are further provided. For example, in a further aspect, a method is provided for changing the color and other physical properties of a material, wherein the material comprises a photoresponsive compound described herein. In some aspects, the method comprises irradiating the material with light of a first wavelength. In some aspects, upon irradiation with the light, the photoresponsive compound converts into a compound of Formula III: . The details of one or more in the accompanying drawings and the description below. Other features, objects, and advantages of the disclosure will be apparent from the description, the drawings, and the claims. DESCRIPTION OF DRAWINGS FIGs.1A-1E provide a comparative overview of donor-acceptor Stenhouse adducts generally and those particularly described in the examples herein. FIG.1A: Isomerization of the donor- acceptor Stenhouse adduct 1 to 1′ upon the absorbance of visible light and its thermal reversion. FIG. 1B: Knoevenagel condensation of 2-furaldehyde with a carbon acid acceptor, followed by furan ring opening with an amine donor to form DASA compounds. FIG. 1C: Synthetic advances of DASA structure per compartment. FIG. 1D: Vital backbone hydroxy group for Attorney Docket No.11760-002WO1 DASA composition highlighted by failure to undergo 4π-electrocyclization with non-hydroxy triene equivalent. FIG.1E: Development of amino DASAs by leveraging nitrogen’s additional bonding orbital to promote a pyrrole-opening rearrangement. FIGs. 2A-2B depict amino DASA synthesis and a ¹³C predictive tool as described in the examples. FIG. 2A: Amino DASA synthetic route, pyrrole-based aza-Piancatelli rearrangement optimization by inductive activation, and characterization of 6e by single crystal X-ray diffraction. Yields shown are representative of the aza-Piancatelli rearrangement. FIG. 2B: A synthetic predictive tool for rearrangement viability based on ¹³C NMR shifts of activated heterocycles. FIGs. 3A-3D depict the photophysical characterization of 1^st, 2^nd, and 3^rd generation DASAs as described in the examples. FIG. 3A: 1^st generation amino DASA 7 and hydroxy DASA 9, FIG.3B: 2^nd generation amino DASA 6e and hydroxy DASA 10, and FIG.3C: 3^rd generation amino DASA 8 and hydroxy DASA 11. Yields are isolated yields. ε = molar absorption coefficient in CH₂Cl₂. FIG.3D: UV-visible absorbance spectra are at 10 µM in CH₂Cl₂. FIGs. 4A-4F depict amino DASA photoisomerization and thermal reversion as described in the examples. Photoswitching comparison of 1st, 2nd, and 3rd generation amino DASAs in (FIG. 4A) CH₂Cl₂ and (FIG. 4B) PhMe measured at their corresponding λ_max. (FIG. 4C) Absorbance decrease of amino DASA 6e and absorbance increase at 381 nm in PhMe upon irradiation. (FIG. 4D) Photoisomerization and thermal reversion of amino DASA 6e and hydroxy DASA 10 in PhMe. (FIG.4E) Evaluation of amino DASA 6e thermal stability. (FIG. 4F) Evaluation of hydroxy DASA 10 thermal stability. FIG. 5 depicts a mechanistic comparison of DASA synthesis and photoisomerization to the aza-Piancatelli rearrangement. FIGs. 6A-6B provide amino DASA 6e photophysical characterization as described in the examples. (FIG.6A) UV-visible absorption measurements of 6e were taken at 10, 5, 1, and 0.5 μM in CH2Cl2. Absorbance measurements were normalized and the λmax was plotted against concentration (M). The slope of linear extrapolation, 54572 is the molar absorption coefficient for 6e (ε = 5.5x104 M^-1cm^-1). (FIG.6B) Solvatochromic analysis was performed by obtaining the UV-visible absorption measurements of 6e in PhMe, Et₂O, THF, EtOAc, CHCl₃, CH₂Cl₂, acetone, DMSO, MeCN, and MeOH. The λ_max of absorbance in each solvent was plotted against the respective polarity value (ETN) using the Dimroth-Reichardt parameters. Attorney Docket No.11760-002WO1 FIGs. 7A-7B provide amino DASA 7 photophysical characterization as described in the examples. (FIG.7A) UV-visible absorption measurements of 7 were taken at 10, 5, 1, and 0.5 μM in CH2Cl2. The λmax was plotted against concentration (M). The slope of linear extrapolation, 104649 is the molar absorption coefficient for 7 (ε = 1.0x105 M^-1cm^-1). (FIG. 7B) Solvatochromic analysis was performed by obtaining the UV-visible absorption measurements of 7 in PhMe, Et₂O, THF, EtOAc, CHCl₃, CH₂Cl₂, acetone, DMSO, MeCN, and MeOH. The λmax of absorbance in each solvent was plotted against the respective polarity value (ETN) using the Dimroth-Reichardt parameters. FIGs. 8A-8B provide amino DASA 8 photophysical characterization as described in the examples. (FIG.8A) UV-visible absorption measurements of 8 were taken at 10, 5, 1, and 0.5 μM in CH₂Cl₂. The λ_max was plotted against concentration (M). The slope of linear extrapolation, 105379 is the molar absorption coefficient for 8 (ε = 1.1x105 M^-1cm^-1). (FIG. 8B) Solvatochromic analysis was performed by obtaining the UV-visible absorption measurements of 8 in PhMe, Et2O, THF, EtOAc, CHCl3, CH2Cl2, acetone, DMSO, MeCN, and MeOH. The λ_max of absorbance in each solvent was plotted against the respective polarity value (ETN) using the Dimroth-Reichardt parameters. FIGs. 9A-9B provide hydroxy DASA 9 photophysical characterization as described in the examples. (FIG.9A) UV-visible absorption measurements of 9 were taken at 10, 5, 1, and 0.5 μM in CH2Cl2. The λmax was plotted against concentration (M). The slope of linear extrapolation, 120534 is the molar absorption coefficient for 9 (ε = 1.2x105 M^-1cm^-1). (FIG. 9B) Solvatochromic analysis was performed by obtaining the UV-visible absorption measurements of 9 in PhMe, Et2O, THF, EtOAc, CHCl3, CH2Cl2, acetone, DMSO, MeCN, and MeOH. The λ_max of absorbance in each solvent was plotted against the respective polarity value (ETN) using the Dimroth-Reichardt parameters. FIGs.10A-10B provide hydroxy DASA 10 photophysical characterization as described in the examples. (FIG. 10A) UV-visible absorption measurements of 10 were taken at 10, 5, 1, and 0.5 μM in CH2Cl2. The λmax was plotted against concentration (M). The slope of linear extrapolation, 122396 is the molar absorption coefficient for 10 (ε = 1.2x105 M^-1cm^-1). (FIG. 10B) Solvatochromic analysis was performed by obtaining the UV-visible absorption measurements of 10 in PhMe, Et₂O, THF, EtOAc, CHCl₃, CH₂Cl₂, acetone, DMSO, MeCN, and MeOH. The λmax of absorbance in each solvent was plotted against the respective polarity value (ETN) using the Dimroth-Reichardt parameters. Attorney Docket No.11760-002WO1 FIGs.11A-11B provide hydroxy DASA 11 photophysical characterization as described in the examples. (FIG. 11A) UV-visible absorption measurements of 11 were taken at 10, 5, 1, and 0.5 μM in CH2Cl2. The λmax was plotted against concentration (M). The slope of linear extrapolation, 233836 is the molar absorption coefficient for 11 (ε = 2.3x105 M^-1cm^-1). (FIG. 11B) Solvatochromic analysis was performed by obtaining the UV-visible absorption measurements of 11 in PhMe, Et2O, THF, EtOAc, CHCl₃, CH₂Cl₂, acetone, DMSO, MeCN, and MeOH. The λmax of absorbance in each solvent was plotted against the respective polarity value (ETN) using the Dimroth-Reichardt parameters. FIGs. 12A-12D depict the solvatochromic slope comparison as described in the examples. (FIG.12A) Charge distribution visual of linear DASA molecule. Greater zwitterionic character is correlated to absorbance sensitivity of solvent polarity. Using the Dimroth-Reichardt solvent polarity parameters, absorbance values were plotted to provide a slope value indicative of charge distribution. Heteroatom comparison across the 1^st (FIG.12B), 2^nd (FIG.12C), and 3^rd (FIG.12D) generation DASA molecules were made. FIGs. 13A-13F provide absorbance measurements of 6e during and after irradiation as described in the examples. Irradiation absorbance measurements in (FIG.13A) CH₂Cl₂, (FIG. 13B) PhMe, and (FIG. 13C) MeOH. Following consumption of 6e λmax in the respective solvents, thermal recovery of open DASA was measured in (FIG. 13D) CH₂Cl₂, (FIG. 13E) PhMe, and (FIG.13F) MeOH. FIGs.14A-14F depict irradiation of 6e with various light sources in methanol as described in the examples. Absorbance decreases measurements using (FIG.14A) 490 nm, (FIG.14B) 590 nm, and (FIG. 14C) no light. Absorbance comparison plots of (FIG. 14D) 6e λmax = 567 nm, (FIG. 14E) 6e λshoulder = 539 nm, and (FIG. 14F) 4e λmax = 381 nm upon irradiation with various light sources. All values are normalized to their respective 6e λ_max = 567 nm. FIG. 15 depicts NMR in situ irradiation of 6e with narrow band 590 nm LED in CDCl3. No closed isomer was observed upon 72 hours of irradiation. No C3–C4 cis→trans isomerization was observed at –15 °C. FIGs. 16A-16E provide absorbance measurements of 7 during and after irradiation as described in the examples. Irradiation absorbance measurements in (FIG.16A) CH₂Cl₂, (FIG. 16B) PhMe, and (FIG. 16C) MeOH. Following consumption of 7 λ_max in the respective solvents, thermal recovery of open DASA was measured in (FIG. 16D) CH2Cl2 and (FIG. 16E) MeOH. Attorney Docket No.11760-002WO1 FIGs. 17A-17D provide absorbance measurements of 8 during and after irradiation as described in the examples. Irradiation absorbance measurements in (FIG.17A) CH₂Cl₂, (FIG. 17B) PhMe, and (FIG. 17C) MeOH. Following consumption of 8 λmax in the respective solvents, thermal recovery of open DASA was measured in (FIG.17D) MeOH. FIGs. 18A-18F provide absorbance measurements of 9 during and after irradiation as described in the examples. Irradiation absorbance measurements in (FIG.18A) CH2Cl2, (FIG. 18B) PhMe, and (FIG. 18C) MeOH. Following consumption of 9 λ_max in the respective solvents, thermal recovery of open DASA was measured in (FIG. 18D) CH2Cl2, (FIG. 18E) PhMe, and (FIG.18F) MeOH. FIGs. 19A-19F provide absorbance measurements of 10 during and after irradiation as described in the examples. Irradiation absorbance measurements in (FIG.19A) CH2Cl2, (FIG. 19B) PhMe, and (FIG. 19C) MeOH. Following consumption of 10 λ_max in the respective solvents, thermal recovery of open DASA was measured in (FIG. 19D) CH2Cl2, (FIG. 19E) PhMe, and (FIG.19F) MeOH. FIGs.20A-20B provide absorbance measurements of 11 during irradiation as described in the examples. Irradiation absorbance measurements in (FIG.20A) CH2Cl2 and (FIG.20B) PhMe. Due to rapid photoswitching, accurate thermal reversion measurements could not be performed. FIGs. 21A-21C depict in situ absorbance measurements in PhMe across a 10 min irradiation period. Switching comparison of 1^st (FIG. 21A), 2^nd (FIG. 21B), and 3rd generation (FIG. 21C) DASAs in PhMe. FIGs.22A-22C depict in situ absorbance measurements in CH2Cl2 across a 10 min irradiation period. Switching comparison of 1^st (FIG. 22A), 2^nd (FIG. 22B), and 3rd generation (FIG. 22C) DASAs in CH2Cl2. FIGs.23A-23C depict in situ absorbance measurements in MeOH across a 10 min irradiation period as described in the examples. Switching comparison of 1^st (FIG.23A), 2^nd (FIG.23B), and 3^rd (FIG.23C) generation DASAs in MeOH. FIGs.24A-24F depict the thermal stability evaluation of DASAs as described in the examples. At 10 μM concentration in PhMe, the stability of DASAs 7 (FIG.24A), 6e (FIG.24B), 8 (FIG. 24C), 9 (FIG.24D), 10 (FIG.24E), and 11 (FIG.24F) were evaluated by absorbance decrease during 40 °C incubation periods in the absence of light. Measurements were taken at time points up until complete consumption of respective λmax. Absorbance measurement of 10 μM Attorney Docket No.11760-002WO1 of activated pyrrole 4e (FIG.24B) and activated furan 4fur (FIG.24F) in PhMe were plotted for comparison. FIG.25 provides the ¹H NMR stack of in situ irradiation of amino DASA 6e. Over the period of 3 days, a 1.0 mg/mL solution of 6e in CDCl3 was irradiated as described in the examples. During that period, 1H NMR (600 MHz) spectra were obtained at 25 °C. After irradiating for 72 hrs, the sample was cooled to –15 °C in the NMR and the spectra was obtained at –15 °C. Notably, no significant spectroscopic changes were observed throughout the experiment or after cooling. FIG.26 provides the ¹H NMR stack of in situ irradiation of hydroxy DASA 10. Over the period of 15 min, a 1.0 mg/mL solution of 10 in CDCl₃ was irradiated as described in the examples. During that period, ¹H NMR (600 MHz) spectra were obtained at 25 °C. Notably, complete conversion of 10 to 10’ was observed within 15 min. FIG. 27 provides a Hammett value analysis of 10 and 6e as described in the examples. pKa values for 4-hydroxybenzoic acid, 3-hydroxybenzoic acid, 4-((4- bromophenyl)sulfonamido)benzoic acid, and 3-((4-bromophenyl)sulfonamido)benzoic acid were calculated using Advanced Chemistry Development(ACD/Labs) Software V11.02. Hammett values were derived by applying calculated pKa values to the Hammett equation. DETAILED DESCRIPTION The following description of the disclosure is provided as an enabling teaching of the disclosure in its best, currently known aspects. Many modifications and other aspects disclosed herein will come to mind to one skilled in the art to which the disclosed compositions and methods pertain, benefiting from the teachings presented in the descriptions herein and the associated drawings. Therefore, it is understood that the disclosures are not limited to the specific aspects disclosed and that modifications and other aspects are intended to be included within the scope of the appended claims. The skilled artisan will recognize many variants and adaptations of the aspects described herein. These variants and adaptations are intended to be included in the teachings of this disclosure and to be encompassed by the claims herein. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. As apparent to those of skill in the art upon reading this disclosure, each of the individual aspects described and illustrated herein has discrete components and features that may be Attorney Docket No.11760-002WO1 readily separated from or combined with the features of any of the other several aspects without departing from the scope or spirit of the present disclosure. Any recited method can be carried out in the order of events recited or any other order that is logically possible. Unless otherwise expressly stated, it is in no way intended that any method or aspect set forth herein be construed as requiring that its steps be performed in a specific order. Accordingly, where a method claim does not explicitly state in the claims or descriptions that the steps are to be limited to a particular order, it is in no way intended that an order be inferred in any respect. This holds for any possible non-express basis for interpretation, including logic concerning arrangement of steps or operational flow, meaning derived from grammatical organization or punctuation, or the number or type of aspects described in the specification. All publications mentioned herein are incorporated by reference to disclose and describe the methods or materials in connection with which the publications are cited. The publications discussed herein are provided solely for their disclosure before the filing date of the present application. The dates of publication provided herein can be different from the actual publication dates, which can require independent confirmation. It is also to be understood that the terminology herein describes particular aspects only and is not intended to be limiting. Unless defined otherwise, all technical and scientific terms herein have the same meaning as commonly understood by one of ordinary skill in the art to which the disclosed compositions and methods belong. It can be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the specification and relevant art and should not be interpreted in an idealized or overly formal sense unless expressly defined herein. Before describing the various aspects of the present disclosure, the following definitions are provided and should be used unless otherwise indicated. Additional terms may be defined elsewhere in the present disclosure. Definitions As used herein, “comprising” is interpreted as specifying the presence of the stated features, integers, steps, or components but does not preclude the presence or addition of one or more features, integers, steps, components, or groups thereof. Moreover, each of the terms “by,” “comprising,” “comprises,” “comprised of,” “including,” “includes,” “included,” “involving,” Attorney Docket No.11760-002WO1 “involves,” “involved,” and “such as” are used in their open, non-limiting sense and may be used interchangeably. Further, the term “comprising” is intended to include examples and aspects encompassed by the terms “consisting essentially of” and “consisting of.” Similarly, “consisting essentially of” is intended to include examples encompassed by the term “consisting of.” As used in the specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context dictates otherwise. Ratios, concentrations, amounts, and other numerical data can be expressed herein in a range format. Further, the endpoints of each of the ranges are significant both in relation to the other endpoint and independently of the other endpoint. There are many values disclosed herein, and each value is also disclosed as “about” that particular value in addition to the value itself. For example, if the value “10” is disclosed, then “about 10” is also disclosed. Ranges can be expressed herein as from “about” one particular value and to “about” another particular value. Similarly, when values are expressed as approximations, using the antecedent “about,” the particular value forms a further aspect. For example, if the value “about 10” is disclosed, then “10” is also disclosed. When a range is expressed, a further aspect includes from the one particular value and to the other particular value. For example, where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the disclosure, e.g., the phrase “x to y” includes the range from ‘x’ to ‘y’ as well as the range greater than ‘x’ and less than ‘y’. The range can also be expressed as an upper limit, e.g., ‘about x, y, z, or less’ and should be interpreted to include the specific ranges of ‘about x,’ ‘about y,’ and ‘about z’ as well as the ranges of ‘less than x,’ ‘less than y.’ and ‘less than z.’ Likewise, the phrase ‘about x, y, z, or greater’ should be interpreted to include the specific ranges of ‘about x,’ ‘about y,’ and ‘about z’ as well as the ranges of ‘greater than x,’ greater than y,’ and ‘greater than z.’ In addition, the phrase “about ‘x’ to ‘y’,” where ‘x’ and ‘y’ are numerical values, includes “about ‘x’ to about ‘y’.” Such a range format is used for convenience and brevity and thus should be interpreted flexibly to include not only the numerical values explicitly recited as the limits of the range but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. To illustrate, a numerical range of “about 0.1% to 5%” should be interpreted to include not only the explicitly recited values of Attorney Docket No.11760-002WO1 about 0.1% to about 5% but also include individual values (e.g., about 1%, about 2%, about 3%, and about 4%) and the sub-ranges (e.g., about 0.5% to about 1.1%; about 5% to about 2.4%; about 0.5% to about 3.2%, and about 0.5% to about 4.4%, and other possible sub-ranges) within the indicated range. As used herein, the terms “about,” “approximate,” “at or about,” and “substantially” mean that the amount or value in question can be the exact value or a value that provides equivalent results or effects as recited in the claims or taught herein. That is, amounts, sizes, formulations, parameters, and other quantities and characteristics are not and need not be exact but may be approximate, larger or smaller, as desired, reflecting tolerances, conversion factors, rounding, measurement error, and the like, and other factors known to those of skill in the art such that equivalent results or effects are obtained. In some circumstances, the value that provides equivalent results or effects cannot be reasonably determined. In such cases, as used herein, “about” and “at or about” mean the nominal value indicated ±10% variation unless otherwise indicated or inferred. In general, an amount, size, formulation, parameter, or other quantity or characteristic is “about,” “approximate,” or “at or about,” whether or not expressly stated to be such. Where “about,” “approximate,” or “at or about” is used before a quantitative value, the parameter also includes the specific quantitative value itself unless expressly stated otherwise. As used herein, “optional” or “optionally” means that the subsequently described event or circumstance can or cannot occur. The description includes instances where said event or circumstance occurs and those where it does not. Compounds are described using standard nomenclature. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as is commonly understood by one of skill in the art to which this disclosure belongs. The compounds described herein include enantiomers, mixtures of enantiomers, diastereomers, tautomers, racemates, and other isomers, such as rotamers, as if each is specifically described unless otherwise indicated or otherwise excluded by context. It is to be understood that the compounds provided herein may contain chiral centers. Such chiral centers may be of either the (R) or (S) configuration. The compounds provided herein may either be enantiomerically pure or be diastereomeric or enantiomeric mixtures. Unless stated to the contrary, a formula with chemical bonds shown only as solid lines and not as wedges or dashed lines contemplates each possible isomer, e.g., each enantiomer, diastereomer, and meso compound, and a mixture of isomers, such as a racemic or scalemic mixture. Attorney Docket No.11760-002WO1 Compounds described herein may contain one or more double bonds and, thus, potentially give rise to cis/trans (E/Z) isomers, as well as other conformational isomers. Unless stated to the contrary, all such possible isomers are contemplated, as well as mixtures of such isomers. Compounds described herein may also present as an equilibrium of tautomers. For example, ketones with an α-hydrogen can exist in an equilibrium of the keto form and the enol form. Likewise, amides with an N-hydrogen can exist in an equilibrium of the amide form and the imidic acid form. Unless stated to the contrary, all possible tautomers of the compounds described herein are contemplated. A dash (“-”) that is not between two letters or symbols is used to indicate a point of attachment for a For example, -(C=O)NH₂ is attached through the carbon of the keto (C=O) group. The term “substituted,” as used herein, means that any one or more hydrogens on the designated atom or group are replaced with a moiety selected from the indicated group, provided that the designated atom’s normal valence is not exceeded and the resulting compound is stable. For example, when the substituent is oxo (i.e., =O), two hydrogens on the atom are replaced. For example, a pyridyl group substituted by oxo is a pyridine. Combinations of substituents and/or variables are permissible only if such combinations result in stable compounds or useful synthetic intermediates. A stable active compound refers to a compound that can be isolated and/or can be formulated into a form with a shelf life of at least one month. A stable manufacturing intermediate or precursor to an active compound is stable if it does not degrade within the period needed for reaction or other use. A stable moiety or substituent group is one that does not degrade, react, or fall apart within the period necessary for use. Non-limiting examples of unstable moieties are those that combine heteroatoms in an unstable arrangement, as typically known and identifiable to those of skill in the art. Any suitable group may be present on a “substituted” or “optionally substituted” position that forms a stable molecule and meets the desired purpose of the disclosure and includes, but is not limited to: halo, nitro, cyano, azido, oxo, C1-C6 alkyl, C1-C6 haloalkyl, C2-C6 alkenyl, C2- C6 alkynyl, (C3-C6 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C6 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C6 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C6 alkyl)-, A^xO-(C0-C6 alkyl)-, A^xS-(C₀-C₆ alkyl)-, (A^xA^yN)-(C₀-C₆ alkyl)-, A^zC(O)-(C₀-C₆ alkyl)-, A^zC(N)-(C₀-C₆ alkyl)-, and A^zS(O)-(C0-C6 alkyl)-, and A^zS(O)2-(C0-C6 alkyl)-, wherein A^x and A^y are independently Attorney Docket No.11760-002WO1 selected at each occurrence from A^a, A^zC(O)-, A^zC(N)-, A^zS(O)-, and A^zS(O)₂-, each of which may be optionally substituted with one or more B groups as allowed by valency; wherein A^z is independently selected at each occurrence from hydrogen, halo, C1-C6alkyl, C1-C6haloalkyl, C₂-C₆alkenyl, C₂-C₆alkynyl, (C₃-C₇cycloalkyl)-(C₀-C₃ alkyl)-, (4- to 6-membered heterocycle)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, -OA^a, -SA^a, and -NA^aA^b, each of which may be optionally substituted with one or more B groups as allowed by valency; wherein A^a and A^b are independently selected at each occurrence from hydrogen, C1-C6alkyl, C1-C6haloalkyl, C2-C6alkenyl, C2-C6alkynyl, (C3-C7cycloalkyl)-(C0-C3 alkyl)-, (4- to 6-membered heterocycle)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, each of which may be optionally substituted by one or more B groups as allowed by valency; and wherein B is independently selected at each occurrence from hydrogen, halo, nitro, cyano, azido, oxo, C1-C6 alkyl, C1-C6 haloalkyl, C2-C6 alkenyl, C2-C6 alkynyl, (C3-C6 cycloalkyl)(C0- C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C6 alkyl)-, (6- to 10- membered monocyclic or bicyclic aryl)-(C0-C6 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₆ alkyl)-, A^pO-, A^pS-, A^pA^qN-, A^oC(O)-, A^oC(O)-O-, A^oC(O)-NA^q-, A^oS(O)2-, A^oS(O)2-O-, and A^oS(O)2-NA^q-, wherein A^o is independently selected at each occurrence from A^p, halo, A^pO-, and A^pA^qN-, and wherein A^p and A^q are independently selected at each occurrence from hydrogen, C1-C6 alkyl, C1-C6 haloalkyl, C2-C6 alkenyl, C2-C6 alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C₀- C6 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C6 alkyl)-, and (5- to 10- membered monocyclic or bicyclic heteroaryl)-(C₀-C₆ alkyl)-. The terms for various functional groups as used herein are not intended to be limited to monovalent radicals and may include polyvalent radical groups as appropriate, such as divalent, trivalent, tetravalent, pentavalent, and hexavalent groups, and the like, based on the position and location of such groups in the compounds described herein as would be readily understood by the skilled person in the context in which said functional groups are recited. _{As used herein, the symbol “ ” (which hereinafter can be referred to as “a point of} attachment bond”) denotes a bond that is a point of attachment between two chemical entities, one of which is depicted as being attached to the point of attachment bond and the other of which is not depicted as being attached to the point of attachment bond. For example, Attorney Docket No.11760-002WO1 “_{” indicates that the chemical entity “XY” is bonded to another chemical entity via} attachment bond. Furthermore, the specific point of attachment to the non-depicted entity can be specified by inference. For example, the compound CH₃-R³, wherein R³ i_{s H or “ ,” infers that when R3 is “XY”, the point of attachment bond is the same bond} as the bond by which R³ is depicted as being bonded to CH3. “Halo” or “halogen” independently indicates any fluoro, chloro, bromo or iodo. The term “nitro,” as used herein, is represented by the formula —NO2. The term “cyano,” as used herein, is represented by the formula —CN The term “azido,” as used herein, is represented by the formula –N3. The term “oxo,” as used herein, is represented by the formula =O. “Alkyl” is a straight chain or branched saturated aliphatic hydrocarbon group. In certain aspects, the alkyl is C1-C2, C1-C3, or C1-C6 (i.e., the alkyl chain can be 1, 2, 3, 4, 5, or 6 carbons in length). The specified ranges, as used herein, indicate an alkyl group with a length of each member of the range described as an independent species. For example, C1-C6alkyl, as used herein, indicates an alkyl group having from 1, 2, 3, 4, 5, or 6 carbon atoms and is intended to mean that each of these is described as an independent species, and C₁-C₄alkyl, as used herein, indicates an alkyl group having from 1, 2, 3, or 4 carbon atoms and is intended to mean that each of these is described as an independent species. When C₀-C_nalkyl is used herein in conjunction with another group, for example (C3-C7cycloalkyl)C0-C4alkyl, or -C0-C4(C3- C₇cycloalkyl), the indicated group, in this case cycloalkyl, is either directly bound by a single covalent bond (C0alkyl), or attached by an alkyl chain, in this case 1, 2, 3, or 4 carbon atoms. Alkyls can also be attached via other groups, such as heteroatoms, such as -O-C₀-C₄alkyl(C₃- C7cycloalkyl). Examples of alkyl include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, n-hexyl, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane. In some aspects, the alkyl group is optionally substituted as described herein. “Cycloalkyl” is a saturated or partially unsaturated mono- or multi-cyclic hydrocarbon ring system. When composed of two or more rings, the rings may be joined together in a fused or bridged fashion. Non-limiting examples of typical cycloalkyl groups include cyclopropyl, Attorney Docket No.11760-002WO1 cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl. In some aspects, the cycloalkyl group is optionally substituted as described herein. “Alkenyl” is a straight or branched chain aliphatic hydrocarbon group having one or more carbon-carbon double bonds, each of which is independently either cis or trans, that may occur at a stable point along the chain. Non-limiting examples include C2-C4alkenyl and C2-C6alkenyl (i.e., having 2, 3, 4, 5, or 6 carbons). The specified ranges as used herein indicate an alkenyl group, with each member of the range described as an independent species, as described above for the alkyl moiety. Examples of alkenyl include but are not limited to, ethenyl and propenyl. In one aspect, the alkenyl group is optionally substituted as described herein. “Alkynyl” is a straight or branched chain aliphatic hydrocarbon group having one or more carbon-carbon triple bonds that may occur at any stable point along the chain, for example, C2- C₄alkynyl or C₂-C₆alkynyl (i.e., having 2, 3, 4, 5, or 6 carbons). The specified ranges as used herein indicate an alkynyl group, with each member of the range described as an independent species, as described above for the alkyl moiety. Examples of alkynyl include, but are not limited to, ethynyl, propynyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-pentynyl, 2-pentynyl, 3-pentynyl, 4-pentynyl, 1-hexynyl, 2-hexynyl, 3-hexynyl, 4-hexynyl, and 5-hexynyl. In one aspect, the alkynyl group is optionally substituted as described herein. “Alkoxy” is an alkyl group, as defined above, covalently bound through an oxygen bridge (-O-). Examples of alkoxy include but are not limited to, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, 2-butoxy, tert-butoxy, n-pentoxy, 2-pentoxy, 3-pentoxy, isopentoxy, neopentoxy, n-hexoxy, 2-hexoxy, 3-hexoxy, and 3-methylpentoxy. Similarly, an “alkylthio” or “thioalkyl” group is an alkyl group as defined above, with the indicated number of carbon atoms covalently bound through a sulfur bridge (-S-). “Alkanoyl” is an alkyl group, as defined above, covalently bound through a carbonyl (C=O) bridge. The carbonyl carbon is included in the number of carbons. For example, C2alkanoyl is a CH3(C=O)- group. In one aspect, the alkanoyl group is optionally substituted as described herein. “Aryl” indicates an aromatic group containing only carbon in the aromatic ring or rings. In one aspect, the aryl group contains 1 to 3 separate or fused rings and is 6 to 14 or 18 ring atoms, without heteroatoms as ring members. When indicated, such aryl groups may be further substituted with carbon or non-carbon atoms or groups. Such substitution may include fusion to a 4- to 7- or 5- to 7-membered saturated or partially unsaturated cyclic group that optionally Attorney Docket No.11760-002WO1 contains 1, 2, or 3 heteroatoms independently selected from N, O, B, P, Si and S, to form, for example, a 3,4-methylenedioxyphenyl group. Aryl groups include, for example, phenyl and naphthyl, including 1-naphthyl and 2-naphthyl. In one aspect, aryl groups are pendant. An example of a pendant ring is a phenyl group substituted with a phenyl group. In one aspect, the aryl group is optionally substituted as described herein. The term “heterocycle” refers to saturated and partially saturated heteroatom-containing ring radicals, where the heteroatoms may be selected from N, O, and S. The term heterocycle includes monocyclic 3-12 members rings, as well as bicyclic 5-16 membered ring systems (which can include fused, bridged, or spiro bicyclic ring systems). It does not include rings containing -O-O-, -O-S-, and -S-S- portions. Examples of saturated heterocycle groups, including saturated 4- to 7-membered monocyclic groups containing 1 to 4 nitrogen atoms [e.g., pyrrolidinyl, imidazolidinyl, piperidinyl, pyrrolinyl, azetidinyl, piperazinyl, and pyrazolidinyl]; saturated 4- to 6-membered monocyclic groups containing 1 to 2 oxygen atoms and 1 to 3 nitrogen atoms [e.g., morpholinyl]; and saturated 3- to 6-membered heteromonocyclic groups containing 1 to 2 sulfur atoms and 1 to 3 nitrogen atoms [e.g., thiazolidinyl]. Examples of partially saturated heterocycle radicals include, but are not limited to, dihydrothienyl, dihydropyranyl, dihydrofuryl, and dihydrothiazolyl. Examples of partially saturated and saturated heterocycle groups include, but are not limited to, pyrrolidinyl, imidazolidinyl, piperidinyl, pyrrolinyl, pyrazolidinyl, piperazinyl, morpholinyl, tetrahydropyranyl, thiazolidinyl, dihydrothienyl, 2,3-dihydro-benzo[1,4]dioxanyl, indolinyl, isoindolinyl, dihydrobenzothienyl, dihydrobenzofuryl, isochromanyl, chromanyl, 1,2-dihydroquinolyl, 1,2,3,4-tetrahydro-isoquinolyl, 1,2,3,4-tetrahydro-quinolyl, 2,3,4,4a,9,9a-hexahydro-1H-3-aza-fluorenyl, 5,6,7-trihydro-1,2,4-triazolo[3,4-a]isoquinolyl, 3,4-dihydro-2H-benzo[1,4]oxazinyl, benzo[1,4]dioxanyl, 2,3,-dihydro-1H-benzo[d]isothazol- 6-yl, dihydropyranyl, dihydrofuryl, and dihydrothiazolyl. Bicyclic heterocycle includes groups wherein the heterocyclic radical is fused with an aryl radical, and the point of attachment is the heterocycle ring. Bicyclic heterocycle also includes heterocyclic radicals that are fused with a carbocyclic radical. Representative examples include, but are not limited to, partially unsaturated condensed heterocyclic groups containing 1 to 5 nitrogen atoms, for example, indoline and isoindoline, partially unsaturated condensed heterocyclic groups containing 1 to 2 oxygen atoms and 1 to 3 nitrogen atoms, partially unsaturated condensed heterocyclic groups containing 1 to 2 sulfur atoms and 1 to 3 nitrogen atoms, and saturated condensed heterocyclic groups containing 1 to 2 oxygen or sulfur atoms. Attorney Docket No.11760-002WO1 “Heteroaryl” refers to a stable monocyclic, bicyclic, or multicyclic aromatic ring that contains from 1 to 4, or in some aspects 1, 2, or 3 heteroatoms selected from N, O, S, B, and P (and typically selected from N, O, and S) with remaining ring atoms being carbon, or a stable bicyclic or tricyclic system containing at least one 5, 6, or 7 membered aromatic ring which contains from 1 to 4, or in some aspects from 1 to 3 or from 1 to 2, heteroatoms selected from N, O, S, B, or P, with remaining ring atoms being carbon. In one aspect, the only heteroatom is nitrogen. In one aspect, the only heteroatom is oxygen. In one aspect, the only heteroatom is sulfur. Monocyclic heteroaryl groups typically have from 5 to 6 ring atoms. In some aspects, bicyclic heteroaryl groups are 8- to 10-membered heteroaryl groups, that is groups containing 8 or 10 ring atoms in which one 5-, 6-, or 7-membered aromatic ring which contains from 1 to 4 heteroatoms selected from N, O, S, B, or P is fused to a second aromatic or non-aromatic ring, wherein the point of attachment is an aromatic ring. When the total number of S and O atoms in the heteroaryl ring exceeds 1, these heteroatoms are not adjacent to one another within the ring. In one aspect, the total number of S and O atoms in the heteroaryl ring is not more than 2. In another aspect, the total number of S and O atoms in the heteroaryl ring is not more than 1. Examples of heteroaryl groups include, but are not limited to, pyridinyl, imidazolyl, imidazopyridinyl, pyrimidinyl, pyrazolyl, triazolyl, pyrazinyl, furyl, thienyl, isoxazolyl, thiazolyl, oxadiazolyl, oxazolyl, isothiazolyl, pyrrolyl, quinolinyl, isoquinolinyl, tetrahydroisoquinolinyl, indolyl, benzimidazolyl, benzofuranyl, cinnolinyl, indazolyl, indolizinyl, phthalazinyl, pyridazinyl, triazinyl, isoindolyl, pteridinyl, purinyl, triazolyl, thiadiazolyl, furazanyl, benzofurazanyl, benzothiophenyl, benzothiazolyl, benzoxazolyl, quinazolinyl, quinoxalinyl, naphthyridinyl, and furopyridinyl. As used herein, the term “derivative” refers to a compound having a structure derived from the structure of a parent compound (e.g., a compound disclosed herein) and whose structure is sufficiently similar to those disclosed herein and based upon that similarity would be expected by one skilled in the art to exhibit the same or similar activities and utilities as the claimed compounds, or to induce, as a precursor, the same or similar activities and utilities as the claimed compound. Exemplary derivatives include but are not limited to, salts, esters, amides, salts of esters or amides, and N-oxides of a parent compound. In one aspect, a derivative is provided of a compound recited herein. In particular aspects, salts of the compounds described herein are also provided. As used herein, substantially pure means sufficiently homogeneous to appear free of readily detectable impurities as determined by standard methods of analysis, such as thin layer Attorney Docket No.11760-002WO1 chromatography (TLC), nuclear magnetic resonance (NMR), gel electrophoresis, high- performance liquid chromatography (HPLC) and mass spectrometry (MS), gas- chromatography mass spectrometry (GC-MS), and similar, used by those of skill in the art to assess such purity, or sufficiently pure such that further purification would not detectably alter the physical and chemical properties, such as enzymatic and biological activities, of the substance. Both traditional and modern methods for purification of the compounds to produce substantially chemically pure compounds are known to those of skill in the art. A substantially chemically pure compound may, however, be a mixture of stereoisomers. Certain materials, compounds, compositions, and components disclosed herein can be obtained commercially or readily synthesized using techniques generally known to those of skill in the art. For example, the starting materials and reagents used in preparing the disclosed compounds and compositions are either available from commercial suppliers such as Sigma-Aldrich, (formerly MilliporeSigma, Burlington, MA) or Thermo Fisher Scientific Inc. (Waltham, MA), or are prepared by methods known to those skilled in the art following procedures set forth in references such as Fieser and Fieser's Reagents for Organic Synthesis (John Wiley and Sons, 2007); Organic Reactions (John Wiley and Sons, 2004); March's Advanced Organic Chemistry, (John Wiley and Sons, 8^th Edition); and Larock's Comprehensive Organic Transformations (John Wiley and Sons, 3^rd edition, 2017). Photoresponsive Compounds The present disclosure provides photoresponsive compounds, more particularly donor-acceptor Stenhouse adducts (DASAs), which have heteroatom substitutions that allow for further tunability of their photoswitching properties. In particular aspects, the photoresponsive compounds described herein successfully replace the hydroxyl group found on the triene moiety of previously described DASAs with other heteroatom-containing moieties, such as nitrogen- and sulfur-containing groups. For example, the presence of a nitrogen-containing group on the triene moiety of a DASA allows for the inclusion of further substituents that can be varied, allowing for greater tuning of the associated physical and optical properties. In one aspect, a photoresponsive compound of Formula I Attorney Docket No.11760-002WO1 (I) wherein: D is a donor group; X¹ is -X²-H, wherein X² is selected from: ; R¹, R², and R³ are each independently selected from hydrogen, azido, halo, C1-C12 alkyl, C1-C12 haloalkyl, 6- to 10-membered monocyclic or bicyclic aryl, -OR⁵, and -SR⁵; X^2a is independently selected at each occurrence from O, NR⁴, and S; R^4a is independently selected at each occurrence from R⁴, -OR⁴, -SR⁴, and -N(R⁴)(R⁴); R⁴ and R⁵ are independently selected at each occurrence from hydrogen, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C6 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C₀-C₃ alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency; Y is independently selected at each occurrence from hydrogen, halo, nitro, cyano, azido, oxo, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C12 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10- membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^xO-(C0-C3 alkyl)-, R^xS-(C0-C3 alkyl)-, (R^xR^yN)-(C0-C3 alkyl)-, R^xO-C(O)-(C0-C3 alkyl)-, R^xS-C(O)-(C0-C3 alkyl)-, (R^xR^yN)C(O)-(C0-C3 alkyl)-, R^xO-S(O)₂-(C₀-C₃ alkyl)-, (R^xR^yN)S(O)₂-(C₀-C₃ alkyl)-, R^zC(O)-O-(C₀-C₃ alkyl)-, Attorney Docket No.11760-002WO1 R^zC(O)-(R^xN)-(C₀-C₃ alkyl)-, R^zS(O)₂-O-(C₀-C₃ alkyl)-, R^zS(O)₂-(R^xN)-(C₀-C₃ alkyl)-, R^zC(O)-(C₀-C₃ alkyl)-, R^zS(O)-(C₀-C₃ alkyl)-, and R^zS(O)₂-(C₀-C₃ alkyl)-; R^x and R^y are independently selected at each occurrence from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C7cycloalkyl)-(C0-C3 alkyl)-, (4- to 6-membered heterocycle)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-; and R^z is independently selected at each occurrence from hydrogen, halo, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C7cycloalkyl)-(C0-C3 alkyl)-, (4- to 6-membered heterocycle)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, -OR^x, -SR^x, and -NR^xR^y. In some aspects, the compound is formed from a compound of Formula II: , wherein all variables are as In some aspects, the carbon-13 nuclear magnetic resonance shift in deuterated chloroform of the carbon labeled * in Formula II is greater than about 111 ppm wherein * corresponds to a of attachment to the remainder of the compound of Formula II. Attorney Docket No.11760-002WO1 In some aspects of Formula I or . In some aspects of Formula I or . In some aspects of Formula I or . In some aspects of Formula I or . In some independent occurrences, X^2a In some independent occurrences, X^2a is independently S. In some independent occurrences, X^2a is independently NR⁴. In some independent occurrences, R^4a is independently R⁴. In some independent occurrences, R^4a is independently -OR⁴. In some independent occurrences, R^4a is independently -N(R⁴)(R⁴). In some aspects of Formula I or . In some aspects of Formula I or . Attorney Docket No.11760-002WO1 In some aspects of Formula I or . In some aspects of Formula I or . In some aspects of Formula I or . R⁴ and R⁵ are independently selected at C1-C12 alkyl, C1-C12 haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency; In some independent occurrences, R⁴ is hydrogen. In some independent occurrences, R⁴ is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, n-hexyl, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane optionally substituted with one or more groups (for example, 1, 2, 3, or 4 groups) selected from Y as allowed by valency. In some independent occurrences, R⁴ is selected from trifluoromethyl, trifluoroethyl, and hexafluoroisopropyl. In some independent occurrences, R⁴ is selected from ethenyl and propenyl optionally substituted with one or more groups (for example, 1, 2, 3, or 4 groups) selected from Y as allowed by valency. Attorney Docket No.11760-002WO1 In some independent occurrences, R⁴ is selected from ethynyl, propynyl, and propargyl optionally substituted with one or more groups (for example, 1, 2, 3, or 4 groups) selected from Y as allowed by valency. In some independent occurrences, R⁴ is selected from cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl optionally substituted with one or more groups (for example, 1, 2, 3, of 4 groups) selected from Y as allowed by valency. In some independent occurrences, R⁴ is selected from pyrrolidinyl, imidazolidinyl, piperidinyl, pyrrolinyl, azetidinyl, piperazinyl, pyrazolidinyl, morpholinyl, tetrahydrofuranyl, tetrahydropyranyl, thiazolidinyl, indolinyl, and isoindolinyl optionally substituted with one or more groups (for example, 1, 2, 3, or 4 groups) selected from Y as allowed by valency. In some independent occurrences, R⁴ is selected from phenyl, 1-naphthyl, and 2-naphthyl optionally substituted with one or more groups (for example, 1, 2, 3, or 4 groups) selected from Y as allowed by valency. In some independent occurrences, R⁴ is selected from pyridinyl, imidazolyl, imidazopyridinyl, pyrimidinyl, pyrazolyl, triazolyl, pyrazinyl, furyl, thienyl, isoxazolyl, thiazolyl, oxadiazolyl, oxazolyl, pyrrolyl, quinolinyl, isoquinolinyl, indolyl, benzimidazolyl, benzofuranyl, indazolyl, indolizinyl, phthalazinyl, pyridazinyl, triazinyl, isoindolyl, pteridinyl, purinyl, thiadiazolyl, furazanyl, benzofurazanyl, benzothiophenyl, benzothiazolyl, benzoxazolyl, quinazolinyl, quinoxalinyl, naphthyridinyl, and furopyridinyl optionally substituted with one or more groups (for example, 1, 2, 3, or 4 groups) selected from Y as allowed by valency. In some aspects of Formula I or Formula II, R⁴ is independently selected at each occurrence from C1-C12 alkyl and 6- to 10-membered monocyclic or bicyclic aryl optionally substituted with one or more groups (for example, 1, 2, 3, or 4 groups) selected from Y as allowed by valency. In some aspects of Formula I, the compound is of Formula I-a: R2 X1 a), wherein all variables are Attorney Docket No.11760-002WO1 In some aspects of Formula I or Formula II, R¹ is hydrogen. In some aspects of Formula I or Formula II, R¹ is azido. In some aspects of Formula I or Formula II, R¹ is halo. In some aspects of Formula I or Formula II, R¹ is selected from fluoro, chloro, bromo, and iodo. In some aspects of Formula I or Formula II, R¹ is C₁-C₁₂ alkyl. In some aspects of Formula I or Formula II, R¹ is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, n-hexyl, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane. In some aspects of Formula I or Formula II, R¹ is C₁-C₁₂ haloalkyl. In some aspects of Formula I or Formula II, R¹ is selected from trifluoromethyl, trifluoroethyl, and hexafluoroisopropyl. In some aspects of Formula I or Formula II, R¹ is 6- to 10-membered monocyclic or bicyclic aryl. In some aspects of Formula I or Formula II, R¹ is selected from phenyl, 1-naphthyl, and 2-naphthyl. In some aspects of Formula I or Formula II, R¹ is -OR⁵. In some aspects of Formula I or Formula II, R¹ is -OR⁵, wherein R⁵ is selected from hydrogen, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some aspects of Formula I or Formula II, R¹ is -SR⁵. In some aspects of Formula I or Formula II, R¹ is -SR⁵, wherein R⁵ is selected from hydrogen, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some aspects of Formula I or Formula II, R² is hydrogen. In some aspects of Formula I or Formula II, R² is azido. In some aspects of Formula I or Formula II, R² is halo. In some aspects of Formula I or Formula II, R² is selected from fluoro, chloro, bromo, and iodo. In some aspects of Formula I or Formula II, R² is C1-C12 alkyl. In some aspects of Formula I or Formula II, R² is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, n-hexyl, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane. In some aspects of Formula I or Formula II, R² is C1-C12 haloalkyl. In some aspects of Formula I or Formula II, R² is selected from trifluoromethyl, trifluoroethyl, and hexafluoroisopropyl. In some aspects of Formula I or Formula II, R² is 6- to 10-membered monocyclic or bicyclic aryl. In some aspects of Formula I or Formula II, R² is selected from phenyl, 1-naphthyl, and 2-naphthyl. In some aspects of Formula I or Formula II, R² is -OR⁵. In some aspects of Formula I or Formula II, R² is -OR⁵, wherein R⁵ is selected from hydrogen, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some aspects of Formula I or Formula II, R² is -SR⁵. In some aspects of Formula I or Formula II, R² is -SR⁵, wherein R⁵ is selected from Attorney Docket No.11760-002WO1 hydrogen, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some aspects of Formula I or Formula II, R³ is hydrogen. In some aspects of Formula I or Formula II, R³ is azido. In some aspects of Formula I or Formula II, R³ is halo. In some aspects of Formula I or Formula II, R³ is selected from fluoro, chloro, bromo, and iodo. In some aspects of Formula I or Formula II, R³ is C1-C12 alkyl. In some aspects of Formula I or Formula II, R³ is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, n-hexyl, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane. In some aspects of Formula I or Formula II, R³ is C1-C12 haloalkyl. In some aspects of Formula I or Formula II, R³ is selected from trifluoromethyl, trifluoroethyl, and hexafluoroisopropyl. In some aspects of Formula I or Formula II, R³ is 6- to 10-membered monocyclic or bicyclic aryl. In some aspects of Formula I or Formula II, R³ is selected from phenyl, 1-naphthyl, and 2-naphthyl. In some aspects of Formula I or Formula II, R³ is -OR⁵. In some aspects of Formula I or Formula II, R³ is -OR⁵, wherein R⁵ is selected from hydrogen, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some aspects of Formula I or Formula II, R³ is -SR⁵. In some aspects of Formula I or Formula II, R³ is -SR⁵, wherein R⁵ is selected from hydrogen, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some aspects of Formula I or Formula II, R¹, R², and R³ are each hydrogen. In some aspects of Formula I, D may comprise any suitable donor group as known in the art to be used in the synthesis of donor-acceptor Stenhouse adducts or other photoresponsive compounds. Representative examples of such donor groups are described in, for example: US2019/0127345A1; Chem. Soc. Rev., 2018, 47, 1910-1937; and Chem. Soc. Rev., 2023, 52, 8245-8294. In some aspects of Formula I, D is selected from: ; wherein: Attorney Docket No.11760-002WO1 R⁶ and R⁷ are independently selected from hydrogen, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)2-, and (R^xR^yN)S(O)2-, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency; or R⁶ and R⁷ are brought together with the carbon to which they are attached to form a 3- to 8- membered monocyclic or bicyclic heterocycle ring or a 5- to 10-membered monocyclic or bicyclic heteroaryl ring, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency; and R⁸ is selected from hydrogen, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C3-C6 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0- C₃ alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)₂-, and (R^xR^yN)S(O)₂-, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency. In some aspects of . In some aspects of Formula I, D is . In some aspects of . In some aspects of , Attorney Docket No.11760-002WO1 ; R⁹ and R¹⁰ are independently hydrogen, C1-C12 alkyl, and 6- to 10-membered monocyclic or bicyclic aryl, each of which may be optionally substituted with one or more Y groups as allowed by valency; R¹¹ and R¹² are independently selected at each occurrence from hydrogen, halo, nitro, cyano, azido, oxo, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₁₂ cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^xO-(C0-C3 alkyl)-, R^xS-(C0-C3 alkyl)-, (R^xR^yN)-(C0-C3 alkyl)-, R^xO-C(O)-(C0-C3 alkyl)-, R^xS-C(O)-(C0-C3 alkyl)-, (R^xR^yN)C(O)- (C₀-C₃ alkyl)-, R^xO-S(O)₂-(C₀-C₃ alkyl)-, (R^xR^yN)S(O)₂-(C₀-C₃ alkyl)-, R^zC(O)-O-(C₀-C₃ alkyl)-, R^zC(O)-(R^xN)-(C0-C3 alkyl)-, R^zS(O)2-O-(C0-C3 alkyl)-, R^zS(O)₂-(R^xN)-(C₀-C₃ alkyl)-, R^zC(O)-(C₀-C₃ alkyl)-, R^zS(O)-(C₀-C₃ alkyl)-, and R^zS(O)₂- (C0-C3 alkyl)-; m is an integer selected from 0 to 4; and X³ and X⁴ are independently selected from a bond, -CH2-, -O-, and -NR¹³-, wherein R¹³ is selected from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C6 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)₂-, and (R^xR^yN)S(O)₂-. In some of the above aspects of D, R⁹ is hydrogen. In some of the above aspects of D, R⁹ is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, n-hexyl, 2-methylpentane, 3-methylpentane, Attorney Docket No.11760-002WO1 2,2-dimethylbutane, and 2,3-dimethylbutane optionally substituted with one or more groups selected from Y as allowed by valency. In some of the above aspects of D, R⁹ is phenyl, 1-naphthyl, and 2-naphthyl optionally substituted with one or more groups selected from Y as allowed by valency. In some of the above aspects of D, R¹⁰ is hydrogen. In some of the above aspects of D, R¹⁰ is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, n-hexyl, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane optionally substituted with one or more groups selected from Y as allowed by valency. In some of the above aspects of D, R¹⁰ is phenyl, 1-naphthyl, and 2-naphthyl optionally substituted with one or more groups selected from Y as allowed by valency. In some of the above aspects of D, X³ is a bond. In some of the above aspects of D, X³ is -CH2-. In some of the above aspects of D, X³ is -O-. In some of the above aspects of D, X³ is -NH- or -N(alkyl or aryl)-. In some of the above aspects of D, X⁴ is a bond. In some of the above aspects of D, X⁴ is -CH2-. In some of the above aspects of D, X⁴ is -O-. In some of the above aspects of D, X⁴ is -NH- or -N(alkyl or aryl)-. Representative examples of D as may be found in Formula I include, but are not limited to: ,

Attorney Docket No.11760-002WO1 . any suitable acceptor group as known in the art to be used in the synthesis of donor-acceptor Stenhouse adducts or other photoresponsive compounds. Representative examples of such acceptor groups are described in, for example: US2019/0127345A1; Chem. Soc. Rev., 2018, 47, 1910-1937; and Chem. Soc. Rev., 2023, 52, 8245-8294. In some aspects of Formula I or Formula II, A is selected from: ; Z¹ and Z³ are independently selected from NR¹⁴ and O; Z² is a Z² is a to form an arylene ring optionally substituted with one or more groups selected from Y; Z⁴ is selected from CR¹⁷ and N; X⁵, X⁶, and X⁷ are independently selected from O, S, or NR¹⁸; R¹³ is C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, or 6- to 10-membered monocyclic or bicyclic aryl optionally substituted with one or more groups selected from Y; R¹⁴ is independently selected at each occurrence from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic Attorney Docket No.11760-002WO1 aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^zC(O)-, R^zS(O)₂-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)₂-, and (R^xR^yN)S(O)₂-; R¹⁵, R¹⁶, and R¹⁷ are independently selected from hydrogen, halo, nitro, cyano, azido, oxo, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C12 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10- membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^xO-(C₀-C₃ alkyl)-, R^xS-(C₀-C₃ alkyl)-, (R^xR^yN)-(C₀-C₃ alkyl)-, R^xO-C(O)-(C0-C3 alkyl)-, R^xS-C(O)-(C0-C3 alkyl)-, (R^xR^yN)C(O)-(C0-C3 alkyl)-, R^xO- S(O)₂-(C₀-C₃ alkyl)-, (R^xR^yN)S(O)₂-(C₀-C₃ alkyl)-, R^zC(O)-O-(C₀-C₃ alkyl)-, R^zC(O)-(R^xN)- (C0-C3 alkyl)-, R^zS(O)2-O-(C0-C3 alkyl)-, R^zS(O)2-(R^xN)-(C0-C3 alkyl)-, R^zC(O)-(C0-C3 alkyl)-, R^zS(O)-(C₀-C₃ alkyl)-, and R^zS(O)₂-(C₀-C₃ alkyl)-; or R¹⁵ and R¹⁶ are brought together with the carbon to which they are attached to form a C₃-C₆ cycloalkyl ring or a 3- to 8-membered monocyclic or bicyclic heterocycle ring; R¹⁸ is independently selected at each occurrence from C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C₂-C₁₂ alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)2-, and (R^xR^yN)S(O)2-. In some aspects of Formula I or Formula II, A is selected from: , Attorney Docket No.11760-002WO1 . C12 alkyl, or 6- to 10-membered monocyclic or bicyclic aryl. In some of the above aspects of A, Z¹ is NR¹⁴, wherein R¹⁴ is hydrogen. In some of the above aspects of A, Z¹ is NR¹⁴, wherein R¹⁴ is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, n-hexyl, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane. In some of the above aspects of A, Z¹ is NR¹⁴, wherein R¹⁴ is selected from phenyl, 1-naphthyl, and 2-naphthyl. In some of the above aspects of A, Z¹ is O. In some of the above aspects of A, Z³ is NR¹⁴, wherein R¹⁴ is selected from hydrogen, C1-C12 alkyl, or 6- to 10-membered monocyclic or bicyclic aryl. In some of the above aspects of A, Z³ is NR¹⁴, wherein R¹⁴ is hydrogen. In some of the above aspects of A, Z³ is NR¹⁴, wherein R¹⁴ is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, n-hexyl, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane. In some of the above aspects of A, Z³ is NR¹⁴, wherein R¹⁴ is selected from phenyl, 1-naphthyl, and 2-naphthyl. In some of the above aspects of A, Z³ is O. In some of the above aspects of A, Z² is a bond. In some of the above aspects of A, Z² is CR¹⁵R¹⁶, wherein R¹⁵ and R¹⁶ are independently selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, Attorney Docket No.11760-002WO1 n-hexyl, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane. In some of the above . In some of the above Z¹ and Z² are brought together to form a phenylene ring optionally substituted with one or more groups (for example, 1, 2, 3, or 4 groups) selected from Y. In some of the above aspects of A, Z⁴ is CR¹⁷, wherein R¹⁷ is cyano. In some of the above aspects of A, Z⁴ is CR¹⁷, wherein R¹⁷ is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, n-hexyl, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane. In some of the above aspects of A, Z⁴ is CR¹⁷, wherein R¹⁷ is selected from trifluoromethyl, trifluoroethyl, and hexafluoroisopropyl. In some of the above aspects of A, Z⁴ is CR¹⁷, wherein R¹⁷ is selected from phenyl, 1-naphthyl, and 2-naphthyl. In some of the above aspects of A, Z⁴ is N. In some of the above aspects of A, X⁵ is O. In some of the above aspects of A, X⁵ is S. In some of the above aspects of A, X⁵ is NR¹⁸, wherein R¹⁸ is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, n-hexyl, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane. In some of the above aspects of A, X⁵ is NR¹⁸, wherein R¹⁸ is selected from phenyl, 1-naphthyl, and 2-naphthyl. In some of the above aspects of A, X⁶ is O. In some of the above aspects of A, X⁶ is S. In some of the above aspects of A, X⁶ is NR¹⁸, wherein R¹⁸ is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, n-hexyl, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane. In some of the above aspects of A, X⁶ is NR¹⁸, wherein R¹⁸ is selected from phenyl, 1-naphthyl, and 2-naphthyl. In some of the above aspects of A, X⁷ is O. In some of the above aspects of A, X⁷ is S. In some of the above aspects of A, X⁷ is NR¹⁸, wherein R¹⁸ is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, n-hexyl, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane. In some of the above aspects of A, X⁷ is NR¹⁸, wherein R¹⁸ is selected from phenyl, 1-naphthyl, and 2-naphthyl. Attorney Docket No.11760-002WO1 In some of the above aspects of A, R¹³ is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, n-hexyl, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane. In some of the above aspects of A, R¹³ is selected from trifluoromethyl, trifluoroethyl, and hexafluoroisopropyl. In some of the above aspects of A, R¹³ is selected from phenyl, 1-naphthyl, and 2-naphthyl. Representative examples of A as may be found in Formula I or Formula II include, but are not limited to: , and iodo. In some independent occurrences of Y, Y is cyano. In some independent occurrences of Y, Y is azido. In some independent occurrences of Y, Y is oxo. In some independent occurrences of Y, Y is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, n-hexyl, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane. In some independent occurrences of Y, Y is selected from trifluoromethyl, trifluoroethyl, and hexafluoroisopropyl. In some independent occurrences of Y, Y is selected from ethenyl and propenyl. In some independent occurrences of Y, Y is selected from ethynyl, propynyl, and propargyl. In some independent occurrences of Y, Y is selected from cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl. In some independent occurrences of Y, Y is selected from pyrrolidinyl, imidazolidinyl, piperidinyl, pyrrolinyl, azetidinyl, piperazinyl, pyrazolidinyl, morpholinyl, tetrahydrofuranyl, tetrahydropyranyl, thiazolidinyl, indolinyl, and isoindolinyl. In some independent occurrences Attorney Docket No.11760-002WO1 of Y, Y is selected from phenyl, 1-naphthyl, and 2-naphthyl. In some independent occurrences of Y, Y is selected from pyridinyl, imidazolyl, imidazopyridinyl, pyrimidinyl, pyrazolyl, triazolyl, pyrazinyl, furyl, thienyl, isoxazolyl, thiazolyl, oxadiazolyl, oxazolyl, pyrrolyl, quinolinyl, isoquinolinyl, indolyl, benzimidazolyl, benzofuranyl, indazolyl, indolizinyl, phthalazinyl, pyridazinyl, triazinyl, isoindolyl, pteridinyl, purinyl, thiadiazolyl, furazanyl, benzofurazanyl, benzothiophenyl, benzothiazolyl, benzoxazolyl, quinazolinyl, quinoxalinyl, naphthyridinyl, and furopyridinyl. In some independent occurrences of Y, Y is R^xO-, wherein R^x is selected from hydrogen, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some independent occurrences of Y, Y is R^xS-, wherein R^x is selected from hydrogen, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some independent occurrences of Y, Y is (R^xR^yN)-, wherein R^x and R^y are independently selected from hydrogen, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some independent occurrences of Y, Y is R^xO-C(O)-, wherein R^x is selected from hydrogen, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some independent occurrences of Y, Y is R^xS-C(O)-, wherein R^x is selected from hydrogen, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some independent occurrences of Y, Y is (R^xR^yN)-C(O)-, wherein R^x and R^y are independently selected from hydrogen, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some independent occurrences of Y, Y is R^xO-S(O)₂-, wherein R^x is selected from hydrogen, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some independent occurrences of Y, Y is (R^xR^yN)-S(O)₂-, wherein R^x and R^y are independently selected from hydrogen, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some independent occurrences of Y, Y is R^zC(O)-O-, wherein R^z is selected from hydrogen, chloro, bromo, -OH, -NH2, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some independent occurrences of Y, Y is R^zC(O)-(R^xN)-, wherein R^x is selected from hydrogen, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl, and wherein R^z is selected from hydrogen, chloro, bromo, -OH, -NH2, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some independent occurrences of Y, Y is R^zS(O)₂-O-, wherein R^z is selected from hydrogen, chloro, bromo, -OH, -NH2, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some Attorney Docket No.11760-002WO1 independent occurrences of Y, Y is R^zS(O)₂-(R^xN)-, wherein R^x is selected from hydrogen, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl, and wherein R^z is selected from hydrogen, chloro, bromo, -OH, -NH2, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some independent occurrences of Y, Y is R^zC(O)-, wherein R^z is selected from hydrogen, chloro, bromo, -OH, -NH₂, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some independent occurrences of Y, Y is R^zS(O)-, wherein R^z is selected from hydrogen, chloro, bromo, -OH, -NH₂, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some independent occurrences of Y, Y is R^zS(O)₂-, wherein R^z is selected from hydrogen, chloro, bromo, -OH, -NH2, methyl, ethyl, isopropyl, trifluoromethyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl. In some aspects, a compound is provided selected from:

Attorney Docket No.11760-002WO1 . described herein are also provided. Processes for Synthesis In another aspect, processes for the synthesis of the photoresponsive compounds described herein are also provided. In some particular aspects, a process is provided for preparing a photoresponsive compound of Formula I, . In some aspects, the II compound of Formula I; wherein all variables are as defined herein. In some aspects, the processes described herein are performed in a polar solvent. In some aspects, the polar solvent is a polar protic solvent. In some aspects, the polar solvent is a fluoroalcohol, such as trifluoroethanol or hexafluoroisopropanol. In some aspects, the polar solvent comprises hexafluoroisopropanol. In some aspects, the process is performed in a mixture of a polar solvent and one or more additional solvents, such as dichloromethane. In Attorney Docket No.11760-002WO1 some aspects, the process may be perfomed in a mixture of hexafluoroisopropanol and dichloromethane. In some aspects, the carbon-13 nuclear magnetic resonance shift in deuterated chloroform of the carbon labeled * in Formula II is greater than about 111 ppm wherein * corresponds to a of attachment to the remainder of the compound of Formula II. In some aspects of the disclosed processes, D-H may comprise any suitable donor as known in the art to be used in the synthesis of donor-acceptor Stenhouse adducts or other photoresponsive compounds. Representative examples of such donors are described in, for example: US2019/0127345A1; Chem. Soc. Rev., 2018, 47, 1910-1937; and Chem. Soc. Rev., 2023, 52, 8245-8294. In some aspects, D-H is selected from: ; In some aspects, D-H is selected from: H , Attorney Docket No.11760-002WO1 ; as applied to the D group in compounds of Formula I are similarly implicitly recited for the particular aspects of the donor D-H as used in the processes described herein. Representative examples of D-H as may be used in the disclosed processes include, but are not limited to: , Formula II by a process comprising: Attorney Docket No.11760-002WO1 Reacting a compound of Formula III the compound of Formula II, wherein all variables are as defined herein. In some aspects of the disclosed processes, H-A-H may comprise any suitable acceptor as known in the art to be used in the synthesis of donor-acceptor Stenhouse adducts or other photoresponsive compounds. Representative examples of such acceptors are described in, for example: US2019/0127345A1; Chem. Soc. Rev., 2018, 47, 1910-1937; and Chem. Soc. Rev., 2023, 52, 8245-8294. In some aspects, H-A-H is selected from: as defined herein. In some aspects, H-A-H is selected from: Attorney Docket No.11760-002WO1 . group in compounds of Formula I and Formula II are similarly implicitly recited for the particular aspects of the donor H-A-H as used in the processes described herein. Representative examples of H-A-H as used in the disclosed processes include, but are not limited to: , Attorney Docket No.11760-002WO1 , the addition, subtraction, or movement of various constituents as described for each compound. Similarly, when one or more chiral centers are present in a molecule, the chirality of the molecule can be changed. Additionally, the synthesis of the compounds used in these processes can involve the protection of various chemical groups, and further, the compounds prepared by the disclosed processes may be subsequently deprotected as appropriate. The use of protection and deprotection and the selection of appropriate protecting groups would be readily known to one skilled in the art. “Protecting group”, as used herein, refers to any conventional functional group that allows one to obtain chemoselectivity in a subsequent chemical reaction. Protecting groups are described, for example, in Peter G. M. Wuts, Greene’s Protective Groups in Organic Synthesis, 5^th Ed., Wiley & Sons, 2014. For a particular compound and/or a particular chemical reaction, a person skilled in the art knows how to select and implement appropriate protecting groups and their associated synthetic methods. Examples of amine protecting groups include acyl and alkoxy carbonyl groups, such as t-butoxycarbonyl (BOC) and [2-(trimethylsilyl)ethoxy]methoxy (SEM). Examples of carboxyl protecting groups include C1-C6 alkoxy groups, such as methyl, ethyl, and t-butyl. Examples of alcohol protecting groups include benzyl, trityl, silyl ethers, and the like. The described processes, or reactions to produce the compounds used in the described processes, can be carried out in solvents indicated herein or in solvents which can be selected by one of skill in the art of organic synthesis. Solvents can be substantially nonreactive with the starting materials (reactants), intermediates, or products under the conditions at which the reaction is carried out, i.e., temperature and pressure. Reactions can be carried out in one solvent or a mixture of more than one solvent. Product or intermediate formation can be monitored according to any suitable method known in the art. For example, product formation can be monitored by spectroscopic means, such as nuclear magnetic resonance spectroscopy Attorney Docket No.11760-002WO1 (e.g., ¹H and ¹³C), infrared spectroscopy, spectrophotometry (e.g., UV-visible), or mass spectrometry, or by chromatography such as high-performance liquid chromatography (HPLC) or thin layer chromatography (TLC). In another aspect, a photoresponsive compound is provided prepared by any of the processes described herein. Methods of Use The photoresponsive compounds described herein may find use as photoswitches. Photoswitches are molecules that undergo a molecular change upon light irradiation. Upon excitation, the molecule transforms from its thermodynamically stable state to a photostationary state. The molecular change may include an isomerization that modifies the photoresponsive compound's absorption spectrum, polarity, molecular volume, or geometric configuration. These modifications to the photoresponsive compound, among others, may be used to control a range of properties, including, but not limited to, surface polarity, membrane permeability, surface patterning, and nanoparticle clustering. For example, these photoresponsive compounds may be formed with highly tunable absorption wavelengths, as well as tunability with respect to media and switchability in both solution and polymeric systems. The photoresponsive compounds of the present disclosure may be tuned and/or modified to operate in a range of media according to any of the processes described herein. In some aspects, the photoresponsive compounds may operate (e.g., complete or nearly complete photoswitching) in one or more of a polar medium, a non-polar medium, a solution phase medium, and a solid phase medium. The photoresponsive compounds may operate in a range of solutions (e.g., solvents) and/or in a solid phase. For example, the photoresponsive compounds may operate in one or more of toluene, 1,4-dioxane, xylenes, anisole, dimethyl sulfoxide (DMSO), tetrahydrofuran (THF), water, methanol, ethanol, acetonitrile, chlorobenzene, N-methylpyrrolidone, dichlorobezene, trichlorobenzene, methylene chloride, acetone, benzene, cyclohexane, hexanes, ethyl acetate, diethyl ether, 1,2-dichloroethane, and chloroform. In addition, the photoresponsive compounds may operate in a polymer matrix. The photoresponsive compounds can be absorbed into the polymer matrix, incorporated through post-functionalization, or polymerized into the backbone of the polymer. Polymer compositions may include one or more (methy)acrylate, (meth)acrylamide, (meth)acrylonitrile, styrene, acrylonitrile, vinyl acetate, vinylcarbazole, vinylpyridine, vinyl ether, vinyl chloride, Attorney Docket No.11760-002WO1 and siloxane monomers. Other solid phase mediums which may be used may include but are not limited to, paper, nylon, and/or fibers. In this aspect, the photoresponsive compounds can be absorbed into the medium and/or covalently attached through post-functionalization. The photoresponsive compounds may also be tuned and/or modified according to any of the processes described herein to absorb wavelengths between about 400 nm and about 800 nm (e.g., about 530 nm to about 700 nm). Upon contacting the photoresponsive compounds with electromagnetic radiation, the photoresponsive compounds may convert from a thermodynamically stable state to a photostationary state. For example, the electromagnetic rotation can mediate an E to Z alkene isomerization that is followed by a thermally driven ring- closure to afford the colorless photostationary state. The conversion of the photoresponsive compounds may induce a color change from a colored state to a completely colorless or nearly colorless state. The conversion of the photoresponsive compounds may also induce a polarity change from hydrophobic to hydrophilic upon contacting electromagnetic radiation. The conversion of the photoresponsive compounds may also, or in the alternative, induce a molecular change (e.g., isomerization) that can be used to convert light into mechanical work. Combined or independently, these property changes can be used to tune the photoresponsive compound's absorption spectrum, polarity, molecular volume, geometric configuration, and/or control various properties, including, but not limited to, surface polarity, surface patterning, membrane permeability, and nanoparticle clustering. A temperature dependence of the thermal reversion of the photoresponsive compounds may be tuned and/or modified according to any of the processes described herein. Temperature dependence can be tuned by modifying either the donor or acceptor group of the photoresponsive compounds that affects the switching kinetics of the system. In this case, the substituents can be used to modify either the sterics or electronics of the system to control the switching kinetics. Alternatively, the temperature dependence can be tuned by modifying the polymer glass transition (Tg). For example, going from a glassy to a rubbery matrix can be used to tune the kinetics of the thermal reversion, with faster reversion being observed in a rubbery matrix. The photoresponsive compounds and their tunable properties provide a material particularly suited for use in applications that include, among other things, photo-responsive drug delivery, photo-responsive phase-tag system, pigment, tattoo pigment, cosmetic pigment, data storage, re-writable systems, and sensors. This shall not be construed as limiting, as the photoresponsive compounds may be used in a number of applications, either known or unknown in the art. Attorney Docket No.11760-002WO1 In some aspects, a photo-responsive drug delivery system, a photo-responsive phase-tag system, pigment, a tattoo pigment, a cosmetic pigment, a data storage system, a re-writable system, a sensor, an electronic system, an energy storage system, a gas uptake and release system, a nanoreactor, a cell mimic, a liquid crystal display, an optical storage system, a photo- pharmacology system, a self-healing material, a polymer phase chemistry system, a wave- selective photo-sensing system, or a photochromic lens comprising a photoresponsive compound described herein. In other aspects, the photoresponsive compounds described herein are for use in a photo- responsive drug delivery system, a photo-responsive phase-tag system, pigment, a tattoo pigment, a cosmetic pigment, a data storage system, a re-writable system, a sensor, an electronic system, an energy storage system, a gas uptake and release system, a nanoreactor, a cell mimic, a liquid crystal display, an optical storage system, a photo-pharmacology system, a self-healing material, a polymer phase chemistry system, a wave-selective photo-sensing system, or a photochromic lens. In another aspect, a method is provided for changing the color of a material, wherein the material comprises a photoresponsive compound described herein. In some aspects, the method comprises: irradiating the material with light of a first wavelength, whereupon irradiation with the light, the photoresponsive compound converts into a compound of Formula III: wherein all variables are as Additional Particular Aspects In view of the described compounds, compositions, and methods, hereinbelow are described certain more particular aspects of the disclosure. These particularly recited aspects should not, however, be interpreted to have any limiting effect on any different claims containing different or more general teachings described herein or that the “particular” aspects are somehow limited Attorney Docket No.11760-002WO1 in some way other than the inherent meanings of the language and formulae literally used therein. Aspect 1. A photoresponsive compound of Formula I R2 X1 (I) wherein: D is a donor group; X¹ is -X²-H, wherein X² is selected from: ; R¹, R², and R³ are each independently selected from hydrogen, azido, halo, C1-C12 alkyl, C1-C12 haloalkyl, 6- to 10-membered monocyclic or bicyclic aryl, -OR⁵, and -SR⁵; X^2a is independently selected at each occurrence from O, NR⁴, and S; R^4a is independently selected at each occurrence from R⁴, -OR⁴, -SR⁴, and -N(R⁴)(R⁴); R⁴ and R⁵ are independently selected at each occurrence from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency; Y is independently selected at each occurrence from hydrogen, halo, nitro, cyano, azido, oxo, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C12 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C₀-C₃ alkyl)-, (6- to 10- membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or Attorney Docket No.11760-002WO1 bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^xO-(C₀-C₃ alkyl)-, R^xS-(C₀-C₃ alkyl)-, (R^xR^yN)-(C₀-C₃ alkyl)-, R^xO-C(O)-(C₀-C₃ alkyl)-, R^xS-C(O)-(C₀-C₃ alkyl)-, (R^xR^yN)C(O)-(C₀-C₃ alkyl)-, R^xO-S(O)2-(C0-C3 alkyl)-, (R^xR^yN)S(O)2-(C0-C3 alkyl)-, R^zC(O)-O-(C0-C3 alkyl)-, R^zC(O)- (R^xN)-(C₀-C₃ alkyl)-, R^zS(O)₂-O-(C₀-C₃ alkyl)-, R^zS(O)₂-(R^xN)-(C₀-C₃ alkyl)-, R^zC(O)-(C₀-C₃ alkyl)-, R^zS(O)-(C0-C3 alkyl)-, and R^zS(O)2-(C0-C3 alkyl)-; R^x and R^y are independently selected at each occurrence from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₇cycloalkyl)-(C₀-C₃ alkyl)-, (4- to 6-membered heterocycle)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-; and R^z is independently selected at each occurrence from hydrogen, halo, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C7cycloalkyl)-(C0-C3 alkyl)-, (4- to 6-membered heterocycle)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, -OR^x, -SR^x, and -NR^xR^y. Aspect 2. The photoresponsive compound of aspect 1, wherein the compound is formed from a compound of Formula II: , wherein all variables are as Aspect 3. The photoresponsive compound of aspect 2, wherein the carbon-13 nuclear magnetic resonance shift in deuterated chloroform of the carbon labeled * in Formula II is greater than about 111 ppm Attorney Docket No.11760-002WO1 wherein * corresponds to a of attachment to the remainder of the compound of Formula II. Aspect 4. The photoresponsive compound of any one of aspects 1-3, wherein X² is . Aspect 5. The one of aspects 1-4, wherein R⁴ is independently selected at each occurrence from C1-C12 alkyl and 6- to 10-membered monocyclic or bicyclic aryl optionally substituted with one or more groups selected from Y as allowed by valency. Aspect 6. The photoresponsive compound of any one of aspects 1-5, wherein the compound is of Formula I-a: . Aspect 7. The photoresponsive compound of any one of aspects 1-6, wherein D is selected from: ; Attorney Docket No.11760-002WO1 wherein: R⁶ and R⁷ are independently selected from hydrogen, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ alkenyl, C2-C12 alkynyl, (C3-C6 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)2-, and (R^xR^yN)S(O)2-, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency; or R⁶ and R⁷ are brought together with the carbon to which they are attached to form a 3- to 8- membered monocyclic or bicyclic heterocycle ring or a 5- to 10-membered monocyclic or bicyclic heteroaryl ring, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency; and R⁸ is selected from hydrogen, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C3-C6 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0- C₃ alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)₂-, and (R^xR^yN)S(O)₂-, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency. Aspect 8. The photoresponsive compound of aspect 7, wherein D is . Aspect 9. The photoresponsive one of aspects 1-6, wherein D is selected from: , Attorney Docket No.11760-002WO1 ; R⁹ and R¹⁰ are independently hydrogen, C1-C12 alkyl, and 6- to 10-membered monocyclic or bicyclic aryl, each of which may be optionally substituted with one or more Y groups as allowed by valency; R¹¹ and R¹² are independently selected at each occurrence from hydrogen, halo, nitro, cyano, azido, oxo, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₁₂ cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^xO-(C0-C3 alkyl)-, R^xS-(C0-C3 alkyl)-, (R^xR^yN)-(C0-C3 alkyl)-, R^xO-C(O)-(C0-C3 alkyl)-, R^xS-C(O)-(C0-C3 alkyl)-, (R^xR^yN)C(O)- (C₀-C₃ alkyl)-, R^xO-S(O)₂-(C₀-C₃ alkyl)-, (R^xR^yN)S(O)₂-(C₀-C₃ alkyl)-, R^zC(O)-O-(C₀-C₃ alkyl)-, R^zC(O)-(R^xN)-(C0-C3 alkyl)-, R^zS(O)2-O-(C0-C3 alkyl)-, R^zS(O)₂-(R^xN)-(C₀-C₃ alkyl)-, R^zC(O)-(C₀-C₃ alkyl)-, R^zS(O)-(C₀-C₃ alkyl)-, and R^zS(O)₂- (C0-C3 alkyl)-; m is an integer selected from 0 to 4; and X³ and X⁴ are independently selected from a bond, -CH2-, -O-, and -NR¹³-, wherein R¹³ is selected from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C6 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)₂-, and (R^xR^yN)S(O)₂-. Aspect 10. The photoresponsive compound of any one of aspects 1-9, wherein A is selected from: Attorney Docket No.11760-002WO1 X5 X5 ; wherein: Z¹ and Z³ are independently selected from NR¹⁴ and O; Z² is a Z² is a bond to form arylene ring optionally substituted with one or more groups selected from Y; Z⁴ is selected from CR¹⁷ and N; X⁵, X⁶, and X⁷ are independently selected from O, S, or NR¹⁸; R¹³ is C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, or 6- to 10-membered monocyclic or bicyclic aryl optionally substituted with one or more groups selected from Y; R¹⁴ is independently selected at each occurrence from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)2-, and (R^xR^yN)S(O)2-; R¹⁵, R¹⁶, and R¹⁷ are independently selected from hydrogen, halo, nitro, cyano, azido, oxo, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₁₂ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10- membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^xO-(C0-C3 alkyl)-, R^xS-(C0-C3 alkyl)-, (R^xR^yN)-(C0-C3 alkyl)-, R^xO-C(O)-(C0-C3 alkyl)-, R^xS-C(O)-(C0-C3 alkyl)-, (R^xR^yN)C(O)-(C0-C3 alkyl)-, R^xO- S(O)₂-(C₀-C₃ alkyl)-, (R^xR^yN)S(O)₂-(C₀-C₃ alkyl)-, R^zC(O)-O-(C₀-C₃ alkyl)-, R^zC(O)-(R^xN)- (C0-C3 alkyl)-, R^zS(O)2-O-(C0-C3 alkyl)-, R^zS(O)2-(R^xN)-(C0-C3 alkyl)-, R^zC(O)-(C0-C3 alkyl)-, R^zS(O)-(C₀-C₃ alkyl)-, and R^zS(O)₂-(C₀-C₃ alkyl)-; or Attorney Docket No.11760-002WO1 R¹⁵ and R¹⁶ are brought together with the carbon to which they are attached to form a C₃-C₆ cycloalkyl ring or a 3- to 8-membered monocyclic or bicyclic heterocycle ring; R¹⁸ is independently selected at each occurrence from C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C6 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^zC(O)-, R^zS(O)₂-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)₂-, and (R^xR^yN)S(O)₂-. Aspect 11. The photoresponsive compound of aspect 10, wherein A is selected from: . from: Attorney Docket No.11760-002WO1 compound of Formula I, R2 X1 (I) the process comprising: reacting a compound of Formula II Attorney Docket No.11760-002WO1 with a donor D-H to form the I; wherein: D is a donor group; X¹ is -X²-H, wherein X² is selected from: ; R¹, R², and R³ are each independently selected from hydrogen, azido, halo, C1-C12 alkyl, C₁-C₁₂ haloalkyl, 6- to 10-membered monocyclic or bicyclic aryl, -OR⁵, and -SR⁵; X^2a is independently selected at each occurrence from O, NR⁴, and S; R^4a is independently selected at each occurrence from R⁴, -OR⁴, -SR⁴, and -N(R⁴)(R⁴); R⁴ and R⁵ are independently selected at each occurrence from hydrogen, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C6 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C₀-C₃ alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency; Y is independently selected at each occurrence from hydrogen, halo, nitro, cyano, azido, oxo, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₁₂ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10- membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or Attorney Docket No.11760-002WO1 bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^xO-(C₀-C₃ alkyl)-, R^xS-(C₀-C₃ alkyl)-, (R^xR^yN)-(C₀-C₃ alkyl)-, R^xO-C(O)-(C₀-C₃ alkyl)-, R^xS-C(O)-(C₀-C₃ alkyl)-, (R^xR^yN)C(O)-(C₀-C₃ alkyl)-, R^xO- S(O)2-(C0-C3 alkyl)-, (R^xR^yN)S(O)2-(C0-C3 alkyl)-, R^zC(O)-O-(C0-C3 alkyl)-, R^zC(O)-(R^xN)- (C₀-C₃ alkyl)-, R^zS(O)₂-O-(C₀-C₃ alkyl)-, R^zS(O)₂-(R^xN)-(C₀-C₃ alkyl)-, R^zC(O)-(C₀-C₃ alkyl)-, R^zS(O)-(C0-C3 alkyl)-, and R^zS(O)2-(C0-C3 alkyl)-; R^x and R^y are independently selected at each occurrence from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₇cycloalkyl)-(C₀-C₃ alkyl)-, (4- to 6-membered heterocycle)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-; and R^z is independently selected at each occurrence from hydrogen, halo, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C7cycloalkyl)-(C0-C3 alkyl)-, (4- to 6-membered heterocycle)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, -OR^x, -SR^x, and -NR^xR^y. Aspect 14. The process of aspect 13, further comprising preparing the compound of Formula II by a process comprising: reacting a compound of Formula III with an acceptor H-A-H to Aspect 15. The process of aspect 13 or aspect 14, wherein the carbon-13 nuclear magnetic resonance shift in deuterated chloroform of the carbon labeled * in Formula II is greater than about 111 ppm Attorney Docket No.11760-002WO1 wherein * corresponds to a of attachment to the remainder of the compound of Formula II. Aspect 16. The process of any one of aspects 13-15, wherein X² is . Aspect 17. The process of any wherein R⁴ is independently selected at each occurrence from C1-C12 alkyl and 6- to 10-membered monocyclic or bicyclic aryl optionally substituted with one or more groups selected from Y as allowed by valency. Aspect 18. The process of any one of aspects 13-17, wherein the compound is of Formula I-a: a). Aspect 19. The D-H is selected from: ; wherein: R⁶ and R⁷ are independently selected from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C6 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or Attorney Docket No.11760-002WO1 bicyclic heterocycle)-(C₀-C₃ alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)2-, and (R^xR^yN)S(O)2-, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency; or R⁶ and R⁷ are brought together with the carbon to which they are attached to form a 3- to 8- membered monocyclic or bicyclic heterocycle ring or a 5- to 10-membered monocyclic or bicyclic heteroaryl ring, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency; and R⁸ is selected from hydrogen, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C3-C6 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0- C₃ alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)₂-, and (R^xR^yN)S(O)₂-, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency. Aspect 20. The process of aspect 19, wherein D-H is . Aspect 21. The process of any one 18, wherein D-H is selected from: ,

Attorney Docket No.11760-002WO1 ; R⁹ and R¹⁰ are independently hydrogen, C1-C12 alkyl, and 6- to 10-membered monocyclic or bicyclic aryl, each of which may be optionally substituted with one or more Y groups as allowed by valency; R¹¹ and R¹² are independently selected at each occurrence from hydrogen, halo, nitro, cyano, azido, oxo, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₁₂ cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^xO-(C0-C3 alkyl)-, R^xS-(C0-C3 alkyl)-, (R^xR^yN)-(C0-C3 alkyl)-, R^xO-C(O)-(C0-C3 alkyl)-, R^xS-C(O)-(C0-C3 alkyl)-, (R^xR^yN)C(O)- (C₀-C₃ alkyl)-, R^xO-S(O)₂-(C₀-C₃ alkyl)-, (R^xR^yN)S(O)₂-(C₀-C₃ alkyl)-, R^zC(O)-O-(C₀-C₃ alkyl)-, R^zC(O)-(R^xN)-(C0-C3 alkyl)-, R^zS(O)2-O-(C0-C3 alkyl)-, R^zS(O)₂-(R^xN)-(C₀-C₃ alkyl)-, R^zC(O)-(C₀-C₃ alkyl)-, R^zS(O)-(C₀-C₃ alkyl)-, and R^zS(O)₂- (C0-C3 alkyl)-; m is an integer selected from 0 to 4; and X³ and X⁴ are independently selected from a bond, -CH2-, -O-, and -NR¹³-, wherein R¹³ is selected from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C6 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)₂-, and (R^xR^yN)S(O)₂-. Aspect 22. The process of any one of aspects 13-21, wherein A is selected from: Attorney Docket No.11760-002WO1 X5 X5 ; wherein: Z¹ and Z³ are independently selected from NR¹⁴ and O; Z² is a Z² is a bond to form arylene ring optionally substituted with one or more groups selected from Y; Z⁴ is selected from CR¹⁷ and N; X⁵, X⁶, and X⁷ are independently selected from O, S, or NR¹⁸; R¹³ is C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, or 6- to 10-membered monocyclic or bicyclic aryl optionally substituted with one or more groups selected from Y; R¹⁴ is independently selected at each occurrence from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)2-, and (R^xR^yN)S(O)2-; R¹⁵, R¹⁶, and R¹⁷ are independently selected from hydrogen, halo, nitro, cyano, azido, oxo, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₁₂ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10- membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^xO-(C0-C3 alkyl)-, R^xS-(C0-C3 alkyl)-, (R^xR^yN)-(C0-C3 alkyl)-, R^xO-C(O)-(C0-C3 alkyl)-, R^xS-C(O)-(C0-C3 alkyl)-, (R^xR^yN)C(O)-(C0-C3 alkyl)-, R^xO- S(O)₂-(C₀-C₃ alkyl)-, (R^xR^yN)S(O)₂-(C₀-C₃ alkyl)-, R^zC(O)-O-(C₀-C₃ alkyl)-, R^zC(O)-(R^xN)- (C0-C3 alkyl)-, R^zS(O)2-O-(C0-C3 alkyl)-, R^zS(O)2-(R^xN)-(C0-C3 alkyl)-, R^zC(O)-(C0-C3 alkyl)-, R^zS(O)-(C₀-C₃ alkyl)-, and R^zS(O)₂-(C₀-C₃ alkyl)-; or Attorney Docket No.11760-002WO1 R¹⁵ and R¹⁶ are brought together with the carbon to which they are attached to form a C₃-C₆ cycloalkyl ring or a 3- to 8-membered monocyclic or bicyclic heterocycle ring; R¹⁸ is independently selected at each occurrence from C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C6 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^zC(O)-, R^zS(O)₂-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)₂-, and (R^xR^yN)S(O)₂-. Aspect 23. The process of aspect 22, wherein A is selected from: . Attorney Docket No.11760-002WO1 ; wherein: Z¹ and Z³ are independently selected from NR¹⁴ and O; Z² is a Z² is a bond to form arylene ring optionally substituted with one or more groups selected from Y; Z⁴ is selected from CR¹⁷ and N; X⁵, X⁶, and X⁷ are independently selected from O, S, or NR¹⁸; R¹³ is C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, or 6- to 10-membered monocyclic or bicyclic aryl optionally substituted with one or more groups selected from Y; R¹⁴ is independently selected at each occurrence from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)2-, and (R^xR^yN)S(O)2-; R¹⁵, R¹⁶, and R¹⁷ are independently selected from hydrogen, halo, nitro, cyano, azido, oxo, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₁₂ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10- membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^xO-(C0-C3 alkyl)-, R^xS-(C0-C3 alkyl)-, (R^xR^yN)-(C0-C3 alkyl)-, R^xO-C(O)-(C0-C3 alkyl)-, R^xS-C(O)-(C0-C3 alkyl)-, (R^xR^yN)C(O)-(C0-C3 alkyl)-, R^xO- S(O)₂-(C₀-C₃ alkyl)-, (R^xR^yN)S(O)₂-(C₀-C₃ alkyl)-, R^zC(O)-O-(C₀-C₃ alkyl)-, R^zC(O)-(R^xN)- (C0-C3 alkyl)-, R^zS(O)2-O-(C0-C3 alkyl)-, R^zS(O)2-(R^xN)-(C0-C3 alkyl)-, R^zC(O)-(C0-C3 alkyl)-, R^zS(O)-(C₀-C₃ alkyl)-, and R^zS(O)₂-(C₀-C₃ alkyl)-; or Attorney Docket No.11760-002WO1 R¹⁵ and R¹⁶ are brought together with the carbon to which they are attached to form a C₃-C₆ cycloalkyl ring or a 3- to 8-membered monocyclic or bicyclic heterocycle ring; R¹⁸ is independently selected at each occurrence from C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C6 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^zC(O)-, R^zS(O)₂-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)₂-, and (R^xR^yN)S(O)₂-. Aspect 25. The process of aspect 24, wherein H-A-H is selected from: . 13- 25. Attorney Docket No.11760-002WO1 Aspect 27. A method for changing the color of a material, wherein the material comprises a photoresponsive compound of any one of aspects 1-12, the method comprising: irradiating the material with light of a first wavelength, whereupon irradiation with the light, the photoresponsive compound converts into a compound of Formula III: wherein all variables are as 1-12. Aspect 28. A photo-responsive drug delivery system, a photo-responsive phase-tag system, pigment, a tattoo pigment, a cosmetic pigment, a data storage system, a re-writable system, a sensor, an electronic system, an energy storage system, a gas uptake and release system, a nanoreactor, a cell mimic, a liquid crystal display, an optical storage system, a photo- pharmacology system, a self-healing material, a polymer phase chemistry system, a wave- selective photo-sensing system, or a photochromic lens comprising a photoresponsive compound of any one of aspects 1-12 and 26. Aspect 29. The photoresponsive compound of any one of aspects 1-12 and 26, wherein the photoresponsive compound is for use in a photo-responsive drug delivery system, a photo- responsive phase-tag system, pigment, a tattoo pigment, a cosmetic pigment, a data storage system, a re-writable system, a sensor, an electronic system, an energy storage system, a gas uptake and release system, a nanoreactor, a cell mimic, a liquid crystal display, an optical storage system, a photo-pharmacology system, a self-healing material, a polymer phase chemistry system, a wave-selective photo-sensing system, or a photochromic lens. A number of aspects of the disclosure have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure. Accordingly, other aspects are within the scope of the following claims. By way of non-limiting illustration, examples of certain aspects of the present disclosure are given below. Attorney Docket No.11760-002WO1 EXAMPLES The following examples are set forth below to illustrate the compounds, compositions, and methods claimed herein, along with associated methods and results according to the disclosed subject matter. These examples are not intended to include all aspects of the subject matter disclosed herein but rather to illustrate representative methods and results. These examples are not intended to exclude equivalents and variations of the present disclosure, which are apparent to one skilled in the art. Efforts have been made to ensure accuracy with respect to numbers (e.g., amounts, temperature, etc.), but some errors and deviations should be accounted for. Unless indicated otherwise, parts are parts by weight, temperature is in °C or is at ambient temperature, and pressure is at or near atmospheric. There are numerous variations and combinations of reaction conditions, e.g., component concentrations, temperatures, pressures, and other reaction ranges and conditions, that can be used to optimize the product purity and yield obtained from the described process. Only reasonable and routine experimentation will be required to optimize such process conditions. Development and Characterization of Amino Donor-Acceptor Stenhouse Adducts Donor-acceptor Stenhouse adducts (DASAs) are molecular photoswitches that have spurred a decade of interest because of their dynamic photophysical properties, complex photoswitching mechanism, and diverse applications. Despite breakthroughs in modularity for the donor, acceptor, and triene compartments, the backbone heteroatom has remained static due to synthetic challenges. We provide in this example a predictive tool and sought-after strategy to vary the heteroatom, introduce amino DASA photoswitches, and analyze backbone heteroatom effects on photophysical properties. Amino DASA synthesis is enabled by the first aza- Piancatelli rearrangements on pyrrole substrates, imparting an aromaticity-breaking rearrangement that capitalizes on nitrogen’s additional bonding orbital and the inductive properties of sulfonyl groups. Amino DASA structure was confirmed by single crystal X-ray diffraction, the photochromic properties were characterized, and the photoswitch isomerization was investigated. Overall, the discovered pyrrole rearrangement enables the study of the DASA backbone heteroatom compartment and furthers our insight into the structure-activity relationship of this complex photoswitch. Attorney Docket No.11760-002WO1 We identified amino DASAs as leading candidates for their ability to enable backbone heteroatom studies. We hypothesized that nitrogen’s additional bonding orbital could be used to inductively activate the heterocycle and develop an unprecedented pyrrole-based rearrangement. Herein, we describe the strategy and realization of such a rearrangement and its application for the synthesis of amino DASA photoswitches that enable backbone heteroatom compartment studies (FIG.1E). Development of Amino DASAs Polarization of the carbon-oxygen bond that is to be cleaved following nucleophile addition is pivotal to furan ring-opening rearrangements. As such, Lewis acids are commonly employed as catalysts to facilitate Piancatelli rearrangements. Despite the extensive use of lanthanide (III) catalysts for various Piancatelli rearrangements, it was discovered that Dy(OTf)₃ only increases DASA production by 10% yield. This observation, along with dysprosium’s high degree of oxaphilicity, led us to consider the alternative approach of using highly polar protic solvents. Polar protic solvents capable of forming H-bonding networks have been used to promote Piancatelli rearrangements, and importantly, hexafluoroisopropanol (HFIP) has been shown to provide a remarkable yield increase in DASA synthesis. The application of HFIP as a cosolvent expanded the library of donor amines capable of forming DASA molecules. Unfortunately, much like the (aza)-Piancatelli rearrangement, furan has been the only heterocycle reported to undergo such reactivity. We initiated our efforts to develop a pyrrole-based rearrangement with the goal to access photoswitches by synthesizing a range of pyrrole-2-carboxaldehyde substrates 2x (FIG. 2A). We leveraged nitrogen’s additional bonding orbital to tune the degree of electron deficiency and pyrrole’s susceptibility to aromaticity-breaking rearrangements. These substrates were then condensed with carbon acid acceptor 1,3-dimethylbarbituric acid (3) to afford activated pyrroles 4x. Lastly, the activated pyrroles were treated with indoline (5) donor in a 4:1 mixture of CH2Cl2:HFIP. (see Table 1 below). As observed by Lalevee and Dumur, pyrrole 4a failed to yield amino DASA product 6a. Methyl pyrrole 4b also failed to yield amino DASA product 6b, ruling out a problematic unprotected pyrrole and supporting our electronic hypothesis. Boc pyrrole 4c and benzoyl pyrrole 4d were reactive but unstable, yielding < 1% desired amino DASAs 6c and 6d, respectively. Excitingly, we discovered that sulfonyl pyrrole 4e was reactive and stable under reaction conditions, yielding the desired photochromic molecule in 74% yield. Attorney Docket No.11760-002WO1 Amino DASA 6e was recrystallized and the structure of the open, linear form was confirmed by single crystal X-ray diffraction. Given interest in modulating the final static component on DASAs and efforts to open thiophene and pyrrole heterocycles for this purpose, we devised a synthetic predictive tool based on ¹³C NMR (FIG. 2B). When characterizing the series of activated heterocycles 4x in CDCl3, we discerned that the ¹³C NMR shift of C7, which is in conjugation with the pyrrole nitrogen, is representative of the heterocycles’s electronic profile. Specifically, unreactive pyrroles 4a and 4b have C7¹³C NMR shifts of 105.8 and 107.0 ppm, respectively, while 4c and 4d, which afforded trace levels of desired DASA product 6x, have C7¹³C NMR shifts of 111.7 and 112.1 ppm, respectively. For reference, thiophene and furan equivalents, 4thio and 4fur, of pyrrole 4x have C7¹³C NMR shifts of 110.7 and 111.6 ppm, respectively. Notably, 4fur successfully undergoes the ring-opening rearrangement while 4thio fails. Given these data, we postulate that a stable activated heterocycle with a C7¹³C NMR shift of 111.0 ppm or greater is positioned to undergo ring opening. Boc and benzoyl pyrroles 4c and 4d do not reliably produce amino DASAs because they are unstable under the reaction conditions. Specifically, reaction of 4c yields a complex mixture of products, while reaction of 4d produces 4a via debenzoylation in 99% yield. Consistent with these postulations, sulfonyl pyrrole 4e, which undergoes ring opening to yield desired amino DASA in 74% yield, has a C7¹³C NMR shift of 112.4 ppm. Hence, sulfonyl groups are ideal for the synthesis of amino DASA photoswitches because they offer sufficient electron withdrawing aptitude and remain intact under the reaction conditions. Characterization of Amino DASAs The developed pyrrole rearrangement granted access to amino DASAs which were then used to understand DASA backbone heteroatom effects. To this end, we synthesized an amino DASA of each generation along with their hydroxy DASA equivalents (FIGs. 3A-3C). First generation amino DASA 7 containing dialkyl amine donor isoindoline was synthesized in 43% yield and hydroxy DASA 9 was prepared in 46% yield. It should be noted that other dialkyl amines were explored but found to be incompatible with HFIP cosolvent, consistent with previous hydroxy DASA reports. No desired reactivity was observed in the absence of HFIP, pointing towards a strong dependence on the H-bond network to sufficiently polarize the C–N bond. Second generation amino DASA 6e and hydroxy counterpart 10, which contain aromatic amine donor indoline, were produced in 74% and 70% yield, respectively. Lastly, third Attorney Docket No.11760-002WO1 generation DASAs that contain the more strongly withdrawing trifluoromethyl pyrazolone acceptor group were synthesized in 87% and 68% yield for amino DASA 8 and hydroxy DASA 11, respectively. Thus, our strategy provides comparable yields of the respective rearranged products and a facile means to vary the final compartment on DASA photoswitches. With representative amino and hydroxy DASAs from each synthetic generation in hand, we set out to characterize their respective physical properties. Initially, we observed that amino DASAs display the same general photoabsorbance trends as parent hydroxy DASAs (FIG. 3D). Specifically, when comparing 7 to 6e, a λmax shift from 531 nm to 578 nm is observed. The bathochromic shift resulting from an aryl amine donor is similarly observed for hydroxy DASAs 9 and 10, with λmax = 573 nm and 615 nm, respectively. Exchanging the acceptor from 1,3-dimethylbarbituric acid to trifluoromethyl pyrazolone results in a bathochromic shift from λmax = 578 nm to 608 nm for amino DASAs 6e and 8 and λmax = 615 nm to 646 nm for hydroxy DASAs 10 and 11, respectively. The bathochromic shifts from aromatic amine donors and strong carbon acid acceptors are due to more diffuse electron delocalization that decreases molecular HOMO-LUMO energetic gaps. Despite similar absorbance shifts of sulfonamide and hydroxy substituted DASAs with varying donors and acceptors, it was noted that 7→6e resulted in a 12% greater λmax shift than 9→10 and a 3% lesser λmax shift when comparing 6e→8 to 10→11. The significant absorbance shift between 7 and 6e signals that the sulfonamide group may be partaking in non-covalent interactions with the donor or imparting electronic effects that amplify changes in the HOMO-LUMO energetic gap. When comparing amino DASAs to their hydroxy counterparts, it was observed that sulfonamide containing DASAs express an average hypsochromic absorbance shift of 39 nm. Specifically, 9 to 7 has a hypsochromic shift of 42 nm, while both 10 to 6e and 11 to 8 have a shift of 37 nm. We suspect that the hypsochromic shift and the larger HOMO-LUMO energy gap is a direct result of stronger electron induction from the sulfonamide. The withdrawing effects of para-bromo sulfonamide can be directly contrasted to that of a hydroxyl group through Hammett value analyses. Using 4-substituted benzoic acid derivatives, we calculated substituent constants of σ = 0.13 for 4-bromo sulfonamide and σ = –0.37 for hydroxyl. Similarly, 3-substituted benzoic acid derivatives, which remove resonance contributions from the analysis, yielded σ = 0.26 and 0.12 for 4-bromo sulfonamide and hydroxyl, respectively. These results are in contrast with electronic contributions from other DASA compartments. Weak donors and strong acceptors both lower the HOMO-LUMO energy gap (vide supra), and electron withdrawing triene substituents also result in a bathochromic shift. It can be postulated Attorney Docket No.11760-002WO1 that steric interactions of the large sulfonamide may perturb orbital overlap but the x-ray crystal structure of 6e shows no evidence of steric induced conformational perturbation. Therefore, it seems the backbone heteroatom electronically affects HOMO and LUMO energies distinctly from the other DASA compartments. In addition to a hypsochromic shift, we found that amino DASAs consistently have a lower molar absorption coefficient than hydroxy DASAs. While 9 only has a slightly higher coefficient than 7 with ɛ = 1.2x10⁵ M^–1cm^–1 compared to 1.0x10⁵ M^–1cm^–1, a stronger effect was observed with DASAs containing an aromatic amine donor. Specifically, 6e has a molar absorption coefficient of 5.5x10⁴ M^–1cm^–1 while 10 has one of 1.2x10⁵ M^–1cm^–1. A similar two- fold increase was observed for 8 and 11 with ɛ = 1.1x10⁵ M^–1cm^–1 and 2.3x10⁵ M^–1cm^–1, respectively. The general decrease in photoabsorbance for DASAs containing a sulfonamide substituent highlights the essential role of the backbone heteroatom group in a DASA’s photoabsorbent character. Recent studies shed light on the importance of charge separation in the open DASA isomer and its effect on kinetics and thermal stability. The zwitterionic character of amino DASAs and their hydroxy counterparts was measured by solvatochromic analysis using the normalized Dimroth–Reichardt ETN parameters. First generation DASAs show that the backbone heteroatom is seemingly innocent in charge separation, providing solvatochromic slopes of – 28 nm/ETN for 7 and –29 nm/ETN for 9. However, such is not the case for second and third generation DASA photoswitches. Analysis of second generation DASAs illustrates that amino DASA 6e has a greater degree of zwitterionic character, yielding a solvatochromic slope of – 11 nm/ETN, while hydroxy counterpart 10 is more neutral with a solvatochromic slope of –3 nm/ETN. Contrary, third generation hydroxy DASA 11 exhibits a higher degree of zwitterionic character, providing a solvatochromic slope of –54 nm/ETN compared to –45 nm/ETN for 8. Although no clear trend is established, it is apparent that the sulfonamide moiety may amplify or attenuate charge separation. This also hints at potential non-covalent interactions between the heteroatom substituent and the donor or acceptor. After characterizing the photochromic properties of amino DASAs, we investigated the switching capabilities as measured by relative UV-vis absorbance (FIGs.4A-4F). Absorbance measurements show that amino DASAs 6e and 7 respond to irradiation with broadband visible light in dichloromethane while only 6e shows absorbance decrease in toluene (FIGs.4A-4B). Interestingly, all three generations of amino DASAs have significantly slower conversion rates than their hydroxy counterparts. In methanol, amino DASAs undergo absorbance decrease but Attorney Docket No.11760-002WO1 do not recover absorbance upon ceasing irradiation; this is consistent with hydroxy DASA switching behaviors, with notable exceptions. Furthermore, neither 6e nor 7 display absorbance recovery in any solvent when taken to complete absorbance depletion. When irradiating amino DASAs an absorbance increase in the 300–400 nm range is observed, which correlates with the production of activated pyrrole 4e (λmax = 381 nm); this effect is shown in FIG. 4C for DASA 6e in toluene. To avoid prolonged irradiation, UV-vis absorbance with in situ broadband irradiation across a ten minute interval was measured (FIG. 4D). Though hydroxy DASAs project switching characteristics respective to their donor and acceptor compositions, most studied amino DASAs fail to switch under these conditions. Only amino DASA 6e displays productive reversible photoswitching with a 14% forward photoisomerization upon ten minutes of irradiation in toluene and full recovery after discontinuing irradiation (FIG.4D). These results are consistent with faster and reversible photoswitching occurring when the backbone heteroatom is more electron donating, further underscoring the importance of the backbone heteroatom in DASA photoswitching behavior. In contrast to Feringa’s non-hydroxy triene, amino DASAs displayed complete absorbance decay after extended periods of irradiation. However, given the lack of reversion coupled with an absorbance increase in the 300–400 nm range, the thermal stability of amino DASAs was in question. Upon incubating 2nd generation DASAs in toluene at 40 °C with no irradiation, a significant absorbance decrease is observed. This is not the case for 1st and 3rd generation DASAs. Upon complete loss of absorbance at λ_max = 578 nm for second generation amino DASA 6e, absorbance at 381 nm corresponding to activated pyrrole 4e increased to 49% conversion (FIG. 4E). In direct contrast, second generation hydroxy DASA 10 displayed absorbance decrease without observed activated furan 4fur formation (FIG.4F). In an effort to observe triene isomerization and cyclization intermediates, we performed a variable temperature NMR in situ irradiation experiment utilizing a narrow band 590 nm LED in chloroform. Narrow light near λmax absorbance excludes potential detrimental effects from broadband exposure. Additionally, amino DASA 6e displays full absorbance decrease upon irradiation in chlorinated solvents as observed in our UV-vis studies using broadband light. However, insignificant changes are observed after 72 hours of irradiation with amino DASA 6e remaining intact, and no isomers are observed when cooling to –15 °C. Therefore, DASAs bearing a more withdrawing sulfonamide group encounter an unproductive C3–C4 cis→trans isomerization in chlorinated solvents at concentrations suitable for NMR acquisition, and Attorney Docket No.11760-002WO1 prolonged irradiation with broadband light leads to eventual decomposition (FIG.4A). Amino DASA 6e is insufficiently soluble for variable temperature NMR in situ irradiation experiments in toluene or methanol. In conclusion, we describe a pyrrole-based aza-Piancatelli rearrangement, a ¹³C NMR predictive tool for rearrangement viability, and their application to develop amino donor- acceptor Stenhouse adducts. Confirmed by single crystal X-ray diffraction, amino DASAs enable tunability of the backbone heteroatom, allowing a direct comparison of sulfonamide- and hydroxy-substituted DASAs from each synthetic generation. In comparison to their hydroxy counterpart, amino DASAs produce potential noncovalent interactions in addition to varying electronic contributions that result in a hypsochromic absorbance shift and inefficient photoswitching. It was discovered that substituting the hydroxy group for a sulfonamide moiety results in a decreased molar absorption coefficient and thermal stability, emphasizing the heteroatom’s role in efficiently stabilizing the photoswitch. Materials and Methods Unless stated otherwise, reactions were conducted in flame-dried glassware using anhydrous solvents (freshly distilled or passed through activated alumina columns). All commercially obtained reagents were used as received unless otherwise specified. Furfural (98%), indoline (98%), and phenylhydrazine (97%) were obtained from Acros Organics B.V.B.A. Pyrrole-2- carboxaldehyde (99%) and N,N-dimethylbarbituric acid (99%) were obtained from Beantown Chemical Corporation. Thiophene-2-carboxaldehyde (>98%) and sodium hydride (60% dispersion in oil) were obtained from Tokyo Chemical Industry. Triethylamine (99%) and 4- dimethylaminopyridine (99%) were obtained from Thermo Fisher Scientific. Di-tert-butyl decarbonate (9%), pyridine (9%), and ethyl 4,4,4-trifluoroacetoacetate (99%) were obtained from Sigma-Aldrich. Acetic acid (glacial) and acetic anhydride (99%) were obtained from Ward’s Science.4-bromobenzenesulfonyl chloride (98%) was obtained from Apollo Scientific. 1-methyl-2-pyrrolecarboxaldehyde (98%) was obtained from Lancaster Synthesis Inc. Isoindoline hydrochloride (97%) was obtained from Ambeed. Hexafluoro-2-propanol (99%) was obtained from Chem-Impex International. Indium (III) bromide (99%) was obtained from STREM Chemicals. Chloroform-d, methylene chloride-d₂ (99.8%), and dimethyl sulfoxide-d₆ (99.9%) were obtained from Cambridge Isotope Laboratories. Furfural, indoline, and hexafluoro-2-propanol were freshly distilled prior to use. Isoindoline was prepared from isoindoline hydrochloride by extracting isoindoline with an alkaline solution (sodium Attorney Docket No.11760-002WO1 hydroxide). Reaction temperatures were controlled using IKA Plates (RCT digital) and the built-in temperature modulators. Thin layer chromatography (TLC) was conducted with EMD gel 60 F254 pre-coated plates (0.25 mm) and visualized using a combination of UV light, potassium permanganate, phosphomolybdic acid, and p-anisaldehyde staining. Silicycle Silica flash P60 (particle size 0.040–0.063 mm) was used for flash column chromatography.¹H NMR spectra were recorded on a Mercury (400 MHz), or Varian spectrometers (500, 600 MHz) and are reported relative to deuterated solvent signals. Data for ¹H NMR spectra are reported as follows: chemical shift (δ ppm), multiplicity, coupling constant (Hz) and integration.¹³C NMR spectra were recorded on Mercury (100 MHz), or Varian spectrometers (125 MHz, 150 MHz) and are reported relative to deuterated solvent signals. IR data were collected on a Mettler Toledo ReactIR 702L equipped with a TE MCT detector, an AgX 6mm x 1.5m Fiber probe interface, and a DiComp diamond probe tip. All IR data are reported in terms of frequency absorption (cm^–1). Melting points were recorded on a VWR melting point apparatus, and high resolution mass (HRMS) spectra were obtained on an Agilent 6545Q-TOF LC/MS. Irradiations were performed with a Dolan-Jenner Fiber-Lite Model 190, using an EKZ halogen bulb (10.8V, 30 Watt, 3100K) via a Dolan-Jenner BGT1826 fiber optic gooseneck on high output. UV- visible spectral data was collected on an Agilent Cary 5000 UV-Vis-NIR Spectrophotometer with a UV quartz 10 mm pathlength cuvette (3.5 mL). Crystallographic data was collected on a Rigaku XtaLAB Synergy-S diffractometer. Irradiation experiments were performed with a Dolan-Jenner Fiber-Lite Model 190, using an EKZ halogen bulb (10.8V, 30 Watt, 3100K) via a Dolan-Jenner BGT1826 fiber optic gooseneck on high output for broad band visible light. The convection-cooled temperature control was confirmed with a control experiment replicating DASA irradiation. Over the course of 12 hours of irradiation of toluene solution, the temperature changed from 26.2 °C to 26.5 °C without fluctuation. NMR in situ irradiation experiment was set up following the protocol from Feldmeier et al. (J. Magn. Reson.232, 39–44 (2013)). The fiber-optic cable (M28L05; Ø400 μm, 0.39 NA, SMA- SMA Fiber Patch Cable, 5 meters), 590 nm Fiber-coupled LED (M590F3; 4.6 mW, FWHM = 18 nm), 490 nm Fiber-coupled LED (M490F4; 2.8 mW, FWHM = 22 nm), LED Driver (1200 mA), and power supply (KPS201) were purchased from Thor Labs. NMR tubes were purchased from Wilmad-LabGlass (SP Scienceware):WGS-5BL, Coaxial Insert for 5 mm NMR Sample Tube and 535-PP-7, 5 mm Thin Wall Precision NMR Sample Tube 7" L, 600MHz. Spectra were measured with a Varian spectrometer (600 MHz). Attorney Docket No.11760-002WO1 Experimental Procedures Amino DASA Synthesis Optimization to A; es n Attorney Docket No.11760-002WO1 Entry 5 6 7 8 Dnr ( iv) Indlin (20) Ind lin (20) I indlin I indlin 7 d es n in

Attorney Docket No.11760-002WO1 Entry 9 10 11 Dnr ( iv) I indlin (12) I indlin (105) I indlin (20) IP d to

Attorney Docket No.11760-002WO1 Purification Optimization Entry 12 13 14 15 D i I i li I i li I i li I i li A ce n

Attorney Docket No.11760-002WO1 Entry 16 D n r ( iv) I ind lin (105) P ion ^aAll experiments were performed at 15–30 mg scale; ^bPurifications were performed at room temperature unless stated otherwise; ^cActivated pyrrole S3 containing trifluoromethyl pyrazolone acceptor was used instead of activated pyrrole 4e; ^dCrude product turned brown before submitting to purification. ¹H NMR showed degradation with only trace levels of DASA; Entry 3 represents the optimal conditions for synthesis of amino DASA 6e; Entry 4 represents the optimal conditions for synthesis of amino DASA 8; Entry 16 represents the optimal conditions for synthesis of amino DASA 7. General Considerations and Notes The difference in nucleophilicity of amine donors required tailoring of reaction conditions. A less nucleophilic donor, such as indoline, requires a higher concentration of nucleophile for greater conversion and yield. In contrast, a more nucleophilic donor, such as isoindoline, requires a lower concentration of amine to preserve the desired DASA product. For example, higher concentrations of isoindoline (greater than 0.17 M) led to the formation of 7, which was then quickly decomposed nonspecifically to multiple byproducts, per TLC analysis. Achieving high conversion and low byproduct formation allowed for successful purification of amino DASA products. It should be noted that each DASA underwent solvent stability and solubility Attorney Docket No.11760-002WO1 studies. We learned that each compound requires individualized purification optimization. Both recrystallization and trituration were found to be more efficient than column chromatography. Synthesis of Substrates 2-phenyl-5-(trifluoromethyl)-2,4-dihydro-3H-pyrazol-3-one (S1). In a 20 mL scintillation vial charged with a magnetic stir bar, ethyl 4,4,4,-trifluoroacetoacetate (1.46 mL, 10 mmol) was added to acetic acid (6 mL) followed by the addition of phenylhydrazine (984 µL, 10 mmol). The mixture stirred at reflux (118 °C) for 18 hours. After 18 hours, the reaction mixture was allowed to slowly cool to room temperature. Upon cooling, the crystallized product was vacuum filtered, washed with water and hexanes, then dried under high-vacuum overnight to provide trifluoromethyl pyrazolone S1 (1.437 g, 63% yield) as a white solid. NMR characterization is of the enol form. ¹H NMR (500 MHz, DMSO-d₆): δ = 7.71 – 7.69 (d, J = 7.8 Hz, 2H), 7.53 – 7.49 (t, J = 7.8 Hz, 2H), 7.40 – 7.37 (t, J = 7.7 Hz, 1H), 5.93 (s, 1H). Spectral data matches previously reported values (see . Clerc, M., Stricker, F., Ulrich, S., Sroda, M., Bruns, N., Boesel, L. F. and Read de Alaniz, J. Promoting the Furan Ring-Opening Reaction to Access New Donor–Acceptor Stenhouse Adducts with Hexafluoroisopropanol. Angew. Chem. Int. Ed.60, 10219–10227 (2021)). tert-butyl 2-formyl-1H-pyrrole-1-carboxylate (2c). In a 20 mL scintillation vial charged with a magnetic stir bar, pyrrole-2-carboxaldehyde (238 mg, 2.5 mmol), di-tert-butyl dicarbonate (600 mg, 2.75 mmol), 4-dimethylaminopyridine (30.5 mg, 0.25 mmol), and triethylamine (1.05 mL, 7.5 mmol) were dissolved in CH₂Cl₂ (6 mL) and stirred until Attorney Docket No.11760-002WO1 consumption of pyrrole-2-carboxaldehyde as monitored by TLC (4:1 hexanes:EtOAc). After 15 hours, the reaction mixture was quenched with water (5 mL). Then saturated sodium bicarbonate (5 mL) was added and the aqueous phase was extracted with CH2Cl2 (3 x 5 mL). The combined organic phases were washed with brine (10 mL), dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude oil was purified by flash chromatography (9:1 hexanes:EtOAc) to provide pyrrole 2c (420 mg, 86% yield) as a yellow oil.¹H NMR (500 MHz, CDCl3): δ = 10.29 (s, 1H), 7.41 – 7.40 (t, J = 1.5 Hz, 1H), 7.14 (d, J = 1.8 Hz, 1H), 6.24 (t, J = 3.0 Hz, 1H), 1.61 (s, 9H). Spectral data matches previously reported values (see Reinus, B. J. and Kerwin, S. M. N-Alkynyl Pyrrole Based Total Synthesis of Shensongine A. Synthesis 51, 4085–4105 (2019)). 1-benzoyl-1H-pyrrole-2-carbaldehyde (2d). To a flame dried 100 mL round-bottom flask, a magnetic stir bar and NaH (300 mg, 7.50 mmol; 60% wt. in paraffin oil) were added. The flask was flushed with N₂, and after adding freshly distilled THF (50 mL, 0.1 M) and stirring, the mixture was cooled to 0 °C. Pyrrole-2-carboxaldehyde (476 mg, 5.0 mmol) was then dissolved in a minimal amount of THF (2 mL) and added dropwise. The mixture was then allowed to stir at 0 °C. After stirring for 1 hour, benzoyl chloride (1.05 g, 7.5 mmol) was added, and the mixture stirred at room temperature for 24 hours. Then saturated ammonium chloride (50 mL) was added and the aqueous phase was extracted with Et₂O (3 x 25 mL). The combined organic phase was washed with brine (50 mL), dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The crude oil was purified by flash chromatography (9:1 benzene:hexanes) to provide pyrrole 2d (492 mg, 49% yield) as a white solid. ¹H NMR (400 MHz, CDCl₃): δ = 9.94 (s, 1H), 7.71 – 7.69 (d, J = 7.7 Hz, 2H), 7.59 – 7.56 (t, J = 7.7 Hz, 1H), 7.46 – 7.42 (t, J = 7.1 Hz, 2H), 7.20 (t, J = 1.8 Hz, 1H), 7.13 (t, J = 1.4 Hz, 1H), 6.29 (s, 1H). Spectral data matches previously reported literature values (see Abell, A. D. and Litten, J. C. Synthesis and Amino Acid Chain Extension of 1-Acylated Hydroxymethylpyrroles. Aust. J. Chem.46, 1473–1483 (1993)). Attorney Docket No.11760-002WO1 1-((4-bromophenyl)sulfonyl)-1H-pyrrole-2-carbaldehyde (2e). To a flame dried 100 mL round-bottom flask, a magnetic stir bar and NaH (316 mg, 7.89 mmol; 60% wt. in paraffin oil) were added. The flask was flushed with N2, and after adding freshly distilled THF (50 mL 0.1M) and stirring, it was cooled to 0 °C. Pyrrole-2-carboxaldehyde (500 mg, 5.26 mmol) was then dissolved in a minimal amount of THF (3 mL) and added dropwise. The mixture was then allowed to stir at 0 °C. After stirring for 1 hour, 4-bromobenzenesulfonyl chloride (2.00 g, 7.89 mmol) was added, and the mixture stirred at room temperature for 1 hour. Then saturated ammonium chloride (50 mL) was added and the aqueous phase was extracted with Et₂O (3 x 25 mL). The combined organic phase was washed with brine (50 mL), dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The crude oil was purified by flash chromatography (9.6:0.3:0.1 → 9.4:0.5:0.1 → 8.9:1.0:0.1 hexanes:EtOAc:NEt3) to provide pyrrole 2e (1.51 g, 91% yield) as a white powder. Rf: 0.70 (59:40:1 hexanes:EtOAc:NEt3); mp: 101–103 ºC; ¹H NMR (500 MHz, CDCl3): δ = 9.84 (s, 1H), 7.82 – 7.80 (m, J = 8.8 Hz, 2H), 7.68 – 7.66 (m, J = 8.7 Hz, 2H), 7.65 – 7.64 (dd, J = 3.3, 1.8 Hz, 1H), 7.17 – 7.16 (dd, J = 3.8, 1.8 Hz, 1H), 6.44 – 6.43 (t, J = 3.4 Hz, 1H); ¹³C NMR (125 MHz, CDCl3): δ = 178.4, 137.1, 133.6, 132.9, 130.1, 129.9, 129.3, 126.3, 112.8; IR (acetone, cm^-1): 1684, 1572, 1388, 1184, 1156, 1088, 1060, 1008, 828, 760, 740; HRMS- QToF-ESI (m/z): [M + H]⁺ calcd. for C11H9BrNO3S⁺, 313.9481; found, 313.9492. 5-((1H-pyrrol-2-yl)methylene)-1,3-dimethylpyrimidine-2,4,6(1H,3H,5H)-trione (4a). In a 50 mL round-bottom flask charged with a magnetic stir bar, pyrrole-2-carboxaldehyde (238 mg, 2.5 mmol) and N,N-dimethylbarbituric acid (468 mg, 3.0 mmol) were dissolved in H₂O Attorney Docket No.11760-002WO1 (25 mL). The mixture stirred at 75 °C for 14 hours. After cooling to room temperature, the yellow precipitant was filtered under vacuum, washed with hexanes, and allowed to dry under high vacuum to provide activated pyrrole 4a (519 mg, 89% yield) as a yellow solid.¹H NMR (600 MHz, CDCl₃): δ = 13.28 (br, 1H), 8.34 (s, 1H), 7.41 (s, 1H), 7.14 (t, J = 1.8 Hz, 1H), 6.54 (m, 1H), 3.42 (s, 3H), 3.40 (s, 3H); ¹³C NMR (150 MHz, CDCl3): δ = 163.9, 163.5, 151.7, 143.2, 131.4, 130.2, 129.7, 114.7, 105.8, 29.0, 28.5. Spectral data matches previously reported values (see . Nemykin, V. N., Schrage, B. R. and Ziegler, C, J. Structure and Electronics in 1H- pyrrol-2-ylmethylene Compounds. Tetrahedron 76, 131149 (2020)). 1,3-dimethyl-5-((1-methyl-1H-pyrrol-2-yl)methylene)pyrimidine-2,4,6(1H,3H,5H)-trione (4b). In a 25 mL round-bottom flask charged with a magnetic stir bar, 1-methyl-2- pyrrolecarboxaldehyde (108 µL, 1.0 mmol) and N,N-dimethylbarbituric acid (187 mg, 1.2 mmol) were dissolved in H2O (10 mL). The mixture stirred at 75 °C for 14 hours. After cooling to room temperature, the yellow precipitant was filtered under vacuum, washed with hexanes, and allowed to dry under high vacuum to provide activated pyrrole 4b (226 mg, 91% yield) as a yellow solid. Rf: 0.16 (4:1 hexanes:EtOAc); mp: 205–209 °C; ¹H NMR (600 MHz, CDCl3): δ = 8.60 – 8.59 (d, J = 4.3 Hz, 1H), 8.44 (s, 1H), 7.20 (s, 1H), 6.43 – 6.42 (dd, J = 4.3, 2.2 Hz, 1H), 3.89 (s, 3H), 3.40 (s, 3H), 3.39 (s, 3H); ¹³C NMR (150 MHz, CDCl3): δ = 164.1, 161.3, 151.9, 139.9, 135.8, 130.0, 128.6, 112.6, 107.0, 35.1, 28.9, 28.2; IR (acetone, cm^-1): 1664, 1564, 1492, 1392, 1348, 1304, 1180, 1064, 788, 756, 704; HRMS-QToF-ESI (m/z): [M + H]⁺ calcd. for C₁₂H₁₄N₃O₃ ⁺, 248.1030; found, 248.1036.

Attorney Docket No.11760-002WO1 tert-butyl 2-((1,3-dimethyl-2,4,6-trioxotetrahydropyrimidin-5(2H)-ylidene)methyl)-1H- pyrrole-1-carboxylate (4c). In a 20 mL scintillation vial charged with a magnetic stir bar, pyrrole 2c (137 mg, 0.7 mmol) and N,N-dimethylbarbituric acid (131 mg, 0.84 mmol) were added to 1:1 EtOH:CH₂Cl₂ (7 mL) and stirred at 40 °C. After 22 hours, the reaction mixture was allowed to cool to room temperature and quenched with water (10 mL). The aqueous phase was extracted with CH₂Cl₂ (3 x 10 mL). The combined organic phases were washed with brine (10 mL), dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The crude solid was purified by flash chromatography (8:2 hexanes:EtOAc) to provide activated pyrrole 4c (216 mg, 93% yield) as a yellow solid. Rf: 0.41 (4:1 hexanes:EtOAc); mp: 141–143 °C; ¹H NMR (500 MHz, CDCl₃): δ = 9.28 (s, 1H), 8.39 – 8.38 (d, J = 2.5 Hz, 1H), 7.72 (m, 1H), 6.44 – 6.43 (t, J = 3.4 Hz, 1H), 3.40 (s, 3H), 3.38 (s, 3H), 1.64 (s, 9H); ¹³C NMR (125 MHz, CDCl3): δ = 163.3, 161.1, 151.7, 148.7, 144.9, 131.3, 130.3, 129.9, 113.0, 111.7, 86.4, 29.1, 28.4, 28.1; IR (acetone, cm^-1): 1748.1672, 1572, 1464, 1428, 1428, 1380, 1316, 1260, 1148, 1128, 1076, 844, 792, 760, 724, 700, 668, 660; HRMS-QToF- ESI (m/z): [M – C5H8O2 + H]⁺ calcd. for C11H12N3O3⁺, 234.0873; found, 234.0891. 5-((1-benzoyl-1H-pyrrol-2-yl)methylene)-1,3-dimethylpyrimidine-2,4,6(1H,3H,5H)- trione (4d). In a 25 mL round-bottom flask charged with a magnetic stir bar, pyrrole 2d (199 mg, 1.0 mmol) and N,N-dimethylbarbituric acid (187 mg, 1.2 mmol) were dissolved in H₂O (10 mL). The mixture stirred at 75 °C for 14 hours. After cooling to room temperature, the yellow precipitant was filtered under vacuum, washed with hexanes, and allowed to dry under high vacuum to provide activated pyrrole 4d (320 mg, 95% yield) as a yellow solid. Rf: 0.17 (4:1 hexanes:EtOAc); mp: 164–168 °C; ¹H NMR (500 MHz, CDCl₃): δ = 8.79 (s, 1H), 8.36 (d, J = 3.7 Hz, 1H), 7.83 – 7.81 (d, J = 7.9 Hz, 2H), 7.69 – 7.66 (t, J = 7.2 Hz, 1H), 7.56 – 7.52 (t, J = 7.8 Hz, 2H), 7.35 (m, 1H), 6.49 – 6.48 (t, J = 3.5 Hz, 1H), 3.38 (s, 3H), 3.36 (s, 3H); ¹³C NMR (125 MHz, CDCl3): δ = 168.4, 163.0, 161.1, 151.7, 144.2, 133.9, 132.9, 132.1, 130.7, 130.7, 130.5, 128.9, 113.3, 112.1, 29.1, 28.4; IR (acetone, cm^-1): 1672, 1572, 1464, 1424, 1376, Attorney Docket No.11760-002WO1 1344, 1312, 1280, 1252, 1164, 1136, 1092, 1032, 872, 792, 756, 724, 696, 676; HRMS-QToF- ESI (m/z): [M + Na]⁺ calcd. for C₁₈H₁₅N₃O₄Na⁺, 360.0955; found, 360.0976. 5-((1-((4-bromophenyl)sulfonyl)-1H-pyrrol-2-yl)methylene)-1,3-dimethylpyrimidine- 2,4,6(1H,3H,5H)-trione (4e). In a 10 mL round-bottom flask charged with a magnetic stir bar, pyrrole 2e (390 mg, 1.241 mmol) and N,N-dimethylbarbituric acid (213 mg, 1.365 mmol) were dissolved in 1:1 EtOH:CH2Cl2 (5 mL) and stirred at room temperature. After 16 hours, the yellow precipitant was filtered under vacuum, washed with hexanes, and allowed to dry under high vacuum to provide activated pyrrole 4e (560 mg, 99% yield) as a yellow solid. Rf: 0.60 (59:40:1 hexanes:EtOAc:NEt₃); mp: 221–223 °C; ¹H NMR (500 MHz, CDCl₃): δ = 9.07 (s, 1H), 8.61 –8.60 (dd, J = 4.1, 1.6 Hz, 1H), 7.88 – 7.88 (dd, J = 3.2, 1.6 Hz, 1H), 7.85 – 7.82 (d, J = 8.5 Hz, 2H), 7.69 – 7.66 (d, J = 8.5 Hz, 2H), 6.57 – 6.55 (t, J = 3.7 Hz, 1H) 3.42 (s, 3H), 3.34 (s, 3H); ¹³C NMR (125 MHz, CDCl3): δ = 162.9, 160.7, 151.4, 140.4, 137.2, 133.3, 132.3, 131.6, 130.5, 129.6, 129.1, 114.3, 112.4, 29.2, 28.4; IR (acetone, cm^-1): 1672, 1576, 1468, 1376, 1348, 1180, 1148, 1132, 1064 , 1012, 792, 748, 668; HRMS-QToF-ESI (m/z): [M + H]⁺ calcd. for C₁₇H₁₅BrN₃O₅S⁺, 451.9910; found, 451.9919. (E)-4-((1-((4- 5- (trifluoromethyl)-2,4-dihydro-3H-pyrazol-3-one (S2. Following a modified procedure from Ogiwara, Y., Takahashi, K., Kitazawa, T. and Sakai, N. Indium(III)-Catalyzed Knoevenagel Attorney Docket No.11760-002WO1 Condensation of Aldehydes and Activated Methylenes Using Acetic Anhydride as a Promoter. J. Org. Chem. 80, 3101–3110 (2015): In a 4 mL dram vial charged with a magnetic stir bar, pyrrole 2e (223 mg, 0.71 mmol), trifluoromethyl pyrazolone S1 (178 mg, 0.781 mmol), and InBr₃ (25 mg, 0.071 mmol) were dissolved in toluene (710 µL). Acetic anhydride (67 µL, 0.71 mmol) was subsequently added and the mixture was stirred at 60 °C for 16 hours. After cooling to room temperature, the mixture was diluted with EtOAc (5 mL), quenched with saturated sodium bicarbonate (5 mL), and the aqueous phase was extracted with EtOAc (3 x 5 mL). Then the combined organic phases were washed with brine (5 mL), dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude solid was purified by flash chromatography (79.5:20.0:0.5 hexanes:EtOAc:NEt₃) to provide activated pyrrole S2 (270 mg, 73%) as an orange solid. Rf: 0.50 (79.5:20.0:0.5 hexanes:acetone:NEt3); mp: 160–166 °C; ¹H NMR (600 MHz, CD2Cl2): δ = 8.99 – 8.98 (dd, J = 4.1, 1.6 Hz, 1H), 8.36 (s, 1H), 7.91 – (dd, J = 3.1, 1.5 Hz, 1H), 7.86 – 7.84 (d, J = 8.7 Hz, 2H), 7.69 (s, 4H), 7.41 – 7.44 (t, J = 8.6 Hz, 2H), 7.27 – 7.24 (t, J = 7.4 Hz, 1H), 6.66 – 6.65 (t, J = 4.0 Hz, 1H); ¹³C NMR (150 MHz, CD2Cl2): δ = 161.1, 137.8, 136.9, 133.4, 133.1, 131.8, 131.2, 130.6, 129.8, 128.9, 128.9, 128.5, 126.2, 121.1, 119.9, 119.4, 116.7, 115.2, 29.8; IR (acetone, cm^-1): 1704, 1644, 1596, 1576, 1508, 1476, 1384, 1264, 1184, 1144, 1068, 1008, 964, 876, 816, 748, 716, 696, 668; HRMS- QToF-ESI (m/z): [M + H]⁺ calcd. for C21H14BrF3N3O3S⁺, 523.9886; found, 523.9916. 1,3-dimethyl-5-(thiophen-2-ylmethylene)pyrimidine-2,4,6(1H,3H,5H)-trione (4thio). In a 20 mL scintillation vial charged with a magnetic sir bar, thiophene-2-carboxaldehyde (935 µL, 10.0 mmol), N,N-dimethylbarbituric acid (1.561 g, 10.0 mmol), and 1 drop of pyridine were added to EtOH (10 mL). The mixture stirred at 80 °C for 18 h. After cooling to room temperature, the precipitant was filtered under vacuum, washed with hexanes, and allowed to dry under high vacuum to provide activated thiophene 4thio (1.984 g, 79%) as a yellow solid. ¹H NMR (600 MHz, CDCl3): δ = 8.75 (s, 1H), 8.01 – 8.00 (d, J = 5.0 Hz, 1H), 7.90 (d, J = 3.8 Hz, 1H), 7.29 – 7.28 (t, J = 4.5 Hz, 1H), 3.42 (d, 6H); ¹³C NMR (150 MHz, CDCl₃): δ = 162.8, 161.9, 151.5, 149.2, 145.6, 142.0, 137.1, 128.4, 110.7, 29.1, 28.3. Spectral data matches Attorney Docket No.11760-002WO1 previously reported values (see Noirbent, G., Xu, Y., Bonardi, A.-H., Duval, S., Gigmes, D., Lalevée, J. and Dumur, F. New Donor-Acceptor Stenhouse Adducts as Visible and Near Infrared Light Polymerization Photoinitiators. Molecules 25, 2317 (2020)). 5-(furan-2-ylmethylene)-1,3-dimethylpyrimidine-2,4,6(1H,3H,5H)-trione (4fur). In a 100 mL round-bottom flask charged with a magnetic stir bar, furfural (828 µL, 10.0 mmol) and N,N-dimethylbarbituric acid (1.561 g, 10.0 mmol) were dissolved in H₂O (40 mL) and stirred at room temperature. After 22 hours, the yellow precipitant was filtered under vacuum, washed with hexanes, and allowed to dry under high vacuum to provide activated furan 4fur (2.243 g, 96%) as a yellow solid.¹H NMR (600 MHz, CDCl3): δ = 8.64 – 8.63 (d, J = 3.8 Hz, 1H), 8.43 (s, 1H), 7.85 (dd, J = 1.7, 0.7 Hz, 1H), 6.74 – 6.73 (ddd, J = 3.9, 1.7, 0.8 Hz, 1H), 3.41 (s, 3H), 3.40 (s, 3H); ¹³C NMR (150 MHz, CDCl3): δ = 162.6, 160.9, 151.5, 151.3, 150.5, 141.1, 128.2, 115.3, 111.6, 29.1, 28.4. Spectral data matches previously reported values (see Clerc, M., Stricker, F., Ulrich, S., Sroda, M., Bruns, N., Boesel, L. F. and Read de Alaniz, J. Promoting the Furan Ring-Opening Reaction to Access New Donor–Acceptor Stenhouse Adducts with Hexafluoroisopropanol. Angew. Chem. Int. Ed.60, 10219–10227 (2021)). (E)-4-(furan-2-ylmethylene)-2-phenyl-5-(trifluoromethyl)-2,4-dihydro-3H-pyrazol-3-one (S3. Following a modified procedure from Ogiwara, Y., Takahashi, K., Kitazawa, T. and Sakai, N. Indium(III)-Catalyzed Knoevenagel Condensation of Aldehydes and Activated Methylenes Using Acetic Anhydride as a Promoter. J. Org. Chem.80, 3101–3110 (2015): In a 4 mL dram vial charged with a magnetic stir bar, furfural (83 µL, 1.0 mmol), trifluoromethyl pyrazolone S1 (228 mg, 1.0 mmol), acetic anhydride (95 µL, 1.0 mmol), and InBr₃ (36 mg 0.1 mmol) were dissolved in toluene (1 mL) and stirred at room temperature. After 24 hours, the mixture was Attorney Docket No.11760-002WO1 concentrated under reduced pressure. The crude solid was purified by flash chromatography (1:1 hexanes:CH₂Cl₂) to provide activated furan S3 (84 mg, 27%) as an orange solid.¹H NMR (600 MHz, CDCl3): δ = 8.92 (d, J = 3.8 Hz, 1H), 7.94 – 7.92 (dd, J = 8.7, 1.1 Hz, 2H), 7.87 (dd, J = 1.7 Hz, 0.6 Hz, 1H), 7.69 (s, 1H), 7.47 – 7.44 (t, J = 7.4 Hz, 2H), 7.29 – 7.26 (t, J = 7.6 Hz, 1H), 6.80 – 6.79 (ddd, J = 3.9, 1.7, 0.8 Hz, 1H). Spectral data matches previously reported values (see Clerc, M., Stricker, F., Ulrich, S., Sroda, M., Bruns, N., Boesel, L. F. and Read de Alaniz, J. Promoting the Furan Ring-Opening Reaction to Access New Donor– Acceptor Stenhouse Adducts with Hexafluoroisopropanol. Angew. Chem. Int. Ed.60, 10219– 10227 (2021)). 5-((1H-pyrrol-2-yl)methylene)-1,3-dimethylpyrimidine-2,4,6(1H,3H,5H)-trione (4a). In a 4 mL dram vial charged with a magnetic stir bar, activated pyrrole 4d (30 mg, 0.089 mmol) was dissolved in 4:1 CH2Cl2:HFIP (0.22 mL). Indoline (20 µL, 0.178 mmol) was subsequently added and the mixture was stirred at room temperature. After 1 hour the mixture was concentrated under reduced pressure to obtain the crude residue.99% yield of 4a was observed in ¹H NMR of the crude residue using 1,3,5-trimethoxybenzene as the internal standard. Synthesis of DASAs

Attorney Docket No.11760-002WO1 4-bromo-N-((2Z,4E)-1-(1,3-dimethyl-2,4,6-trioxotetrahydropyrimidin-5(2H)-ylidene)-5- (indolin-1-yl)penta-2,4-dien-2-yl)benzenesulfonamide (6e). In a 4 mL dram vial charged with a magnetic stir bar, activated pyrrole 4e (300 mg, 0.663 mmol) was dissolved in 4:1 CH₂Cl₂:HFIP (1.1 mL). Indoline (150 µL, 1.326 mmol) was subsequently added and the mixture was stirred at room temperature. An immediate color change to purple was observed. After 1 hour the mixture was concentrated under reduced pressure, and the crude residue was recrystallized using CH2Cl2 as solvent and hexanes as antisolvent to provide amino DASA 6e (280 mg, 74% yield) as a purple solid. Crystals of 6e suitable for X-ray diffraction analysis were obtained by recrystallization via vapor diffusion of Et2O into a solution of 6e in CHCl3. R_f: 0.40 (97:2:1 CH₂Cl₂:MeOH:NEt₃); ¹H NMR (600 MHz, CDCl₃): δ = 10.06 (s, 1H), 7.89 – 7.87 (d, J = 12.3 Hz, 1H), 7.65 (s, 1H), 7.51 – 7.50 (d, J = 8.4 Hz, 2H), 7.44 – 7.41 (m, 3H), 7.33 – 7.32 (t, J = 8.4 Hz, 2H), 7.20 – 7.15 (m, 2H), 6.65 – 6.61 (t, J = 12.4 Hz, 1H), 4.27 – 4.24 (t, J = 8.0 Hz, 2H), 3.38 – 3.35 (t, J = 8.0 Hz, 2H), 3.29 (s, 3H), 3.29 (s, 3H); ¹³C NMR (150 MHz, CDCl3): δ = 162.9, 160.4, 152.5, 151.4, 146.2, 141.7, 138.1, 133.2, 131.6, 129.1, 128.7, 127.8, 126.6, 126.5, 124.8, 110.4, 107.5, 101.9, 49.8, 29.9, 28.7, 28.4, 27.6; IR (HFIP, cm^-1): 1684, 1600, 1580, 1528, 1444, 1392, 1288, 1240, 1224, 1188, 1176, 1128, 1008, 980, 864, 780, 760, 704, 684, 672, 664; UV-Vis (CH₂Cl₂): λ_max = 578 nm; HRMS-QToF-ESI (m/z): [M + Na]⁺ calcd. for C25H23BrN4O5SNa⁺, 593.0465; found, 593.0483. Crystal structure analysis Diffraction intensities were collected at 100 K on a Rigaku XtaLAB Synergy-S diffractometer equipped with an HyPix-600HE detector and an Oxford Cryostream 800 low temperature unit, using Cu K_α PhotonJet-S X-ray source, 1.54164 Å. The frames were integrated using the SAINT algorithm to give the hkl files. Data were corrected for absorption effects using the multi-scan method (SADABS) with Rigaku CrysalisPro. The structures were solved by intrinsic phasing and refined with the SHELXTL Software Package. Deposition Number 2312996 contains the supplementary crystallographic data provided by the joint Cambridge Crystallographic Data Centre and Fachinformationszentrum Karlsruhe Access Structures service www.ccdc.cam.ac.uk/structures. Attorney Docket No.11760-002WO1 4-bromo-N-((2Z,4E)-1-(1,3-dimethyl-2,4,6-trioxotetrahydropyrimidin-5(2H)-ylidene)-5- (isoindolin-2-yl)penta-2,4-dien-2-yl)benzenesulfonamide (7). In a 4 mL dram vial charged with a magnetic stir bar, activated pyrrole 4e (100 mg, 0.221 mmol) was dissolved in 4:1 CH₂Cl₂:HFIP (1.3 mL). Isoindoline (26 µL, 0.232 mmol) was subsequently added and the mixture was stirred at room temperature. An immediate color change to orange was observed and the solution then turned dark red over time. After 2 hours the mixture was concentrated under reduced pressure, and the crude residue was recrystallized using CHCl3 as solvent and Et2O as antisolvent to provide amino DASA 7 (55 mg, 43% yield) as a red solid. Rf : 0.40 (97:2:1 CH2Cl2:MeOH:NEt3); ¹H NMR (400 MHz, CDCl3): δ = 10.09 (s, 1H), 7.70 – 7.67 (d, J = 12.2 Hz, 1H), 7.59 (s, 1H), 7.51 – 7.48 (d, J = 8.6 Hz, 2H), 7.43 – 7.30 (m, 7H), 6.56 – 6.50 (t, J = 12.4 Hz, 1H), 5.11 (s, 2H), 4.99 (s, 2H), 3.29 (s, 3H), 3.28 (s, 3H); ¹³C NMR (125 MHz, CDCl3): δ = 163.1, 162.9, 161.8, 156.6, 152.1, 151.6, 138.1, 134.4, 133.9, 131.5, 129.0, 128.8, 127.8, 123.5, 123.2, 122.9, 122.7, 106.9, 100.3, 58.8, 55.3, 28.7, 28.3; IR (CH₂Cl₂, cm^-1): 1788, 1644, 1620, 1608, 1476, 1448, 1368, 1308, 1276, 1240, 1200, 1148, 1084, 1012, 976, 940, 904, 856, 780, 748, 684, 672; UV-Vis (CH₂Cl₂): λ_max = 531 nm; HRMS-QToF-ESI (m/z): [M + H]⁺ calcd. for C25H24BrN4O5S⁺, 571.0645; found, 571.0674. 4-bromo-N-((1Z,2Z,4E)-5-(indolin-1-yl)-1-(5-oxo-1-phenyl-3-(trifluoromethyl)-1,5- dihydro-4H-pyrazol-4-ylidene)penta-2,4-dien-2-yl)benzenesulfonamide (8). In a 4 mL Attorney Docket No.11760-002WO1 dram vial charged with a magnetic stir bar, activated pyrrole S2 (100 mg, 0.191 mmol) was dissolved in 4:1 CH₂Cl₂:HFIP (320 mL). Indoline (43 µL, 0.382 mmol) was subsequently added and the mixture was stirred at room temperature. An immediate color change to purple was observed. After 1 hour the mixture was concentrated under reduced pressure, and the crude residue was recrystallized using CH2Cl2 as solvent and hexanes as antisolvent to provide amino DASA 8 (107 mg, 87% yield) as a blue solid. R_f: 0.60 (97:2:1 CH₂Cl₂:MeOH:NEt₃); ¹¹H NMR (500 MHz, CDCl3): δ = 11.00 (br, 1H), 7.97 – 7.95 (d, J = 12.1 Hz, 1H), 7.92 – 7.90 (d, J = 7.4 Hz, 2H), 7.53 – 7.52 (d, J = 8.6 Hz, 2H), 7.44 – 7.41 (t, J = 7.7, 2H), 7.38 – 7.19 (m, 7H), 7.15 – 7.14 (d, J = 8.0 Hz, 1H), 6.86 (s, 1H), 6.74 – 6.69 (t, J = 12.4 Hz, 1H), 4.30 – 4.27 (t, J = 7.8 Hz, 2H), 3.38 – 3.35 (t, J = 7.8 Hz, 2H); ¹³C NMR (125 MHz, CDCl₃): δ = 162.7, 159.1, 147.7, 142.7, 141.1, 138.5, 137.6, 133.8, 132.5, 131.5, 128.9, 128.7, 128.2, 128.1, 127.5, 126.7, 126.5, 125.7, 121.7, 120.0, 119.5, 111.0, 109.5, 50.2, 47.4, 29.9, 27.6; IR (HFIP, cm^-1): 1600, 1572, 1488, 1376, 1284, 1220, 1176, 1168, 1148, 1072, 996, 884, 808, 760, 724, 688; UV-Vis (CH2Cl2): λmax = 608 nm; HRMS-QToF-ESI (m/z): [M + H]⁺ calcd. for C29H23BrF3N4O3S⁺, 643.0621; found, 643.0655. 5-((2Z,4E)-2-hydroxy-5-(isoindolin-2-yl)penta-2,4-dien-1-ylidene)-1,3- dimethylpyrimidine-2,4,6(1H,3H,5H)-trione (9). In a 4 mL dram vial charged with a magnetic stir bar, isoindoline (59 µL, 0.525 mmol) was added to 4:1 CH₂Cl₂:HFIP (1 mL). Activated furan 4fur (117 mg, 0.5 mmol) was subsequently added and the mixture was stirred at room temperature. An immediate color change to purple was observed. After 20 minutes, the mixture was allowed to sit at 0 ºC for 15 minutes. The solid precipitant was vacuum filtered and washed with hexanes. The crude solid was purified by flash chromatography (99.5:0.5 → 98:2 CH₂Cl₂:MeOH) to provide DASA 9 (81 mg, 46% yield) as a purple solid. R_f: 0.28 (95:5 CH2Cl2:MeOH); ¹H NMR (600 MHz, 3:2 CDCl3:HFIP): δ = 12.92 (s, 1H), 7.92 – 7.90 (d, J = 11.5 Hz, 1H), 7.45 – 7.41 (m, 2H), 7.38 – 7.33 (m, 2H), 7.14 – 7.12 (d, J = 13.4 Hz, 1H), 6.74 (s, 1H), 6.38 – 6.34 (t, J = 12.4 Hz, 1H), 5.21 (s, 2H), 5.04 (s, 2H), 3.30 (s, 6H); ¹³C NMR (150 MHz, 3:2 CDCl₃:HFIP): δ = 206.2, 165.3, 160.8, 156.5, 153.5, 152.9, 149.9, 145.8, 140.5, 133.4, 132.9, 130.8, 129.6, 129.4, 123.1, 60.0, 55.9, 28.5, 28.0; IR (HFIP, cm^-1): 2960, 2928, Attorney Docket No.11760-002WO1 2876, 2796, 2368, 2332, 2284, 2264, 2184, 2156, 1972, 1848, 1828, 1792, 1772, 1736, 1708, 1684, 1648, 1540, 1520, 1492, 1476, 1456, 1396, 1376, 1204, 1144, 1076, 760, 696; UV-Vis (CH2Cl2): λmax 573 nm; HRMS-QToF-ESI (m/z): [M + Na]⁺ calcd. for C19H19N3O4Na⁺, 376.1268; found, 376.1293. 5-((2Z,4E)-2-hydroxy-5-(indolin-1-yl)penta-2,4-dien-1-ylidene)-1,3-dimethylpyrimidine- 2,4,6(1H,3H,5H)-trione (10). ). In a 4 mL dram vial charged with a magnetic stir bar, indoline (59 µL, 0.525 mmol) was added to 4:1 CH2Cl2:HFIP (1 mL). Activated furan 4fur (117 mg, 0.5 mmol) was subsequently added and the mixture was stirred at room temperature. An immediate color change to blue was observed. After 15 minutes, the mixture was concentrated under reduced pressure, redissolved in a minimal amount of THF, and added dropwise to vigorously stirring cold Et2O (50 mL). The solid precipitant was vacuum filtered to provide a 1:2 open(10):closed(10′) isomeric mixture of DASA 10 (125 mg, 70% yield) as a blue solid. ¹H NMR (500 MHz, CDCl3): Select shifts of closed isomer 10′, δ = 7.69 – 7.67 (d, J = 6.1 Hz, 1H), 7.39 (s, 1H), 7.11 – 7.07 (m, 2H), 7.01 –6.44 – 6.42 (d, J = 7.0 Hz, 1H), 5.37 (b, 1H), 5.30 (d, J = 1.6 Hz, 2H), 4.13 – 4.09 (t, J = 7.9 Hz, 1H), 3.36 – 3.30 (m, 9H), 3.06 – 3.00 (m, 1H). Spectral data matches previously reported values (see Hemmer, J. R., Poelma, S. O., Treat, N., Page, Z. A., Dolinski, N. D., Diaz, Y. J., Tomlinson, W., Clark, K. D., Hooper, J. P., Hawker, C. and Read de Alaniz, J. Tunable Visible and Near Infrared Photoswitches. J. Am. Chem. Soc. 138, 13960–13966 (2016)). (Z)-4-((2Z,4E)-2-hydroxy-5-(indolin-1-yl)penta-2,4-dien-1-ylidene)-2-phenyl-5- (trifluoromethyl)-2,4-dihydro-3H-pyrazol-3-one (11). In a 4 mL dram vial charged with a Attorney Docket No.11760-002WO1 magnetic stir bar, indoline (24 µL, 0.21 mmol) was added to 4:1 CH₂Cl₂:HFIP (0.5 mL). Activated furan S3 (60 mg, 0.2 mmol) was subsequently added and the mixture was stirred at room temperature. An immediate color change to blue was observed. After 20 minutes, the mixture was concentrated under reduced pressure, redissolved in a minimal amount of THF, and added dropwise to vigorously stirring cold Et2O (50 mL). The solid precipitant was vacuum filtered and purified by flash chromatography (99.5:0.5 → 98:2 CH₂Cl₂:MeOH) to provide DASA 11 (58 mg, 68% yield) as a green solid.¹H NMR (500 MHz, CDCl3): δ = 13.02 (s, 1H), 7.93 – 7.91 (d, J = 8.0 Hz, 2H), 7.74 – 7.72 (d, J = 12.6 Hz, 1H), 7.42 – 7.40 (t, J = 7.8 Hz, 2H), 7.30 – 7.21 (m, 3H), 7.07 – 7.04 (m, 2H), 6.72 – 6.70 (d, J = 12.3 Hz, 1H), 6.63 (s, 1H), 6.33 – 6.28 (t, J = 12.4 Hz, 1H), 4.18 – 4.16 (t, J = 7.8 Hz, 2H), 3.35 – 3.33 (t, J = 7.0 Hz, 2H). Spectral data matches previously reported values (see Sroda, M. M. Stricker, F., Peterson, J. A., Bernal, A. and Read de Alaniz, J. Donor–Acceptor Stenhouse Adducts: Exploring the Effects of Ionic Character. Chem. Eur. J.27, 4183–4190 (2021)). Absorbance Irradiation Experiments Attorney Docket No.11760-002WO1 UV-visible absorption of 10 μM under irradiation using a broadband visible light source were measured at time points across extended periods. All absorbance values were normalized using λmax of time = 0 min as 1. Following complete consumption of λmax, thermal reversion of closed isomer back to open DASA was measured by respective λ_max measurements at 5 second intervals in the absence of irradiation for a period of 1 hour. If λmax consumption was not observed, thermal reversion measurements were not performed. Due to hydroxy DASA 11’s rapid switching rates, accurate measurements could not be obtained. Photoswitching Studies Photoswitching studies with in situ absorbance measurements obtained at 5 sec intervals over 40 min unless otherwise noted.^* Measurements were taken throughout a 2 min dark period, a 10 min irradiation period with a broadband visible light source, and a subsequent 28 min dark period. All measurements were taken at the DASA’s respective λmax in the given solvent. All concentrations were 10 μM.^† Notes *Measurement intervals at 0.1 sec were taken for 10 in PhMe, CH₂Cl₂, and MeOH, and for 6e in MeOH †During irradiation a large amount of absorbance measurement noise appeared. Change of irradiation set-up and measurement parameters did not fix noise issue, but only dampened intensity. However, general absorbance changes and thermal reversion observations are consistent with other experiments. Calculation notes The λ_max of 6e (578 nm) and 4e (381 nm) were plotted across the 96-hour time period. Normalization of the absorbance values were obtained by dividing by absorbance measurements by the t = 0 (initial measurement) of 6e λ_max for 6e plot and by dividing by absorbance measurements by the 4e λmax at 10 μM for 4e plot. References The references below cited are hereby incorporated by reference to disclose and describe the methods or materials in connection with which the publications are cited. Attorney Docket No.11760-002WO1 1. Helmy, S., Leibfarth, F. A., Oh, S., Poelma, J. E., Hawker, C. J. & Read de Alaniz, J. Photoswitching Using Visible Light: A New Class of Organic Photochromic Molecules. J. Am. Chem. Soc.136, 8169–8172 (2014). 2. Lerch, M. M., Szymanski, W. & Feringa, B. L. The (Photo)chemistry of Stenhouse Photoswitches: Guiding Principles and System Design. Chem. Soc. Rev.47, 1910–1937 (2018). 3. Clerc, M., Sandlass, S., Rifaie-Graham, O., Peterson, J. A., Bruns, N., Read de Alaniz, J. & Boesel, L. F. Visible Light-Responsive Materials: The (Photo)chemistry and Applications of Donor-Acceptor Stenhouse Adducts in Polymer Science. Chem Soc. Rev. 52, 8245–8294 (2023). 4. Seshardi, S., Gockowski, L. F., Lee, J., Sroda, M., Helgeson, M. E., Read de Alaniz, J. & Valentine, M. T. Self-Regulating Photochemical Rayleigh-Benard Convection using a Highly-Absorbing Organic Photoswitch. Nat. Commun.11, 2599 (2020). 5. Rifaie-Graham, O., Yeow, J., Najer, A., Wang, R., Sun, R., Zhou, K., Dell, T. N., Adrianus, C., Thanapongpibul, C., Chami, M., Mann, S., Read de Alaniz, J. & Stevens, M. M. Photoswitchable Gating of Non-Equilibrium Enzymatic Feedback in Chemically Communicating Polymersome Nanoreactors. Nat. Chem.15, 110–118 (2023). 6. Stricker, F., Seshadri, S. & Read de Alaniz, J. Donor-Acceptor Stenhouse adducts in Molecular Photoswitches: Chemistry, Properties, and Applications. Wiley-VCH GmbH 1, 303– 324 (2022). 7. Helmy, S., Oh, S., Leibfarth, F. A., Hawker, C. J. & Read de Alaniz, J. Design and Synthesis of Donor–Acceptor Stenhouse Adducts: A Visible Light Photoswitch Derived from Furfural. J. Org. Chem.79, 11316–11329 (2014). 8. Stricker, F., Peterson, J. & Read de Alaniz, J. Preparation of a Donor-Acceptor Stenhouse Adduct (DASA): 5-((2Z,4E)-5-(Diethylamino)-2-hydroxypenta-2,4-dien-1- ylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione. Org. Synth.99, 79–91 (2022). 9. Lerch, M. M., Hansen, M. J., Velema, W. A., Szymanski, W. & Feringa, B. L. Orthogonal Photoswitching in a Multifunctional Molecular System. Nat. Commun. 7, 12054 (2016). 10. Hemmer, J. R., Poelma, S. O., Treat, N., Page, Z. A., Dolinski, N. D., Diaz, Y. J., Tomlinson, W., Clark, K. D., Hooper, J. P., Hawker, C. & Read de Alaniz, J. Tunable Visible and Near Infrared Photoswitches. J. Am. Chem. Soc.138, 13960–13966 (2016). Attorney Docket No.11760-002WO1 11. Mallo, N., Brown, P. T., Iranmanesh, H., MacDonald, T. S. C., Teusner, M. J., Harper, J. B., Ball, G. E. & Beves, J. E. Photochromic Switching Behavior of Donor-Acceptor Stenhouse Adducts in Organic Solvents. Chem. Comm.52, 13576–13579 (2016). 12. Sroda, M. M., Stricker, F., Peterson, J. A., Bernal, A. & Read de Alaniz, J. Donor– Acceptor Stenhouse Adducts: Exploring the Effects of Ionic Character. Chem. Eur. J.27, 4183– 4190 (2021). 13. Stricker, F., Peterson, J., Sandlass, S. K., de Tagyos, A., Sroda, M., Seshadri, S., Gordon, M. J. & Read de Alaniz, J. Selective Control of Donor-Acceptor Stenhouse Adduct Populations with Non-Selective Stimuli. Chem 9, 1994–2005 (2023). 14. Hemmer, J. R., Page, Z. A., Clark, K. D., Stricker, F., Dolinski, N. D., Hawker, C. J. & Read de Alaniz, J. Controlling Dark Equilibria and Enhancing Donor–Acceptor Stenhouse Adduct Photoswitching Properties through Carbon Acid Design. J. Am. Chem. Soc. 140, 10425–10429 (2018). 15. Martinez-Lopez, D., Santamaria-Aranda, E., Marazzi, M., Garcia-Iriepa, C. & Sampedro, D. π-Bridge Substitution in DASAs: The Subtle Equilibrium between Photochemical Improvements and Thermal Control. Chem. Eur. J.27, 4420–4429 (2021). 16. Peterson, J. A., Stricker, F. & Read de Alaniz, J. Improving the Kinetics and Dark Equilibrium of Donor–Acceptor Stenhouse Adduct by Triene Backbone Design. Chem. Comm. 58, 2303–2306 (2022). 17. Lerch, M. M., Medved, M., Lapini, A., Laurent, A. D., Iagatti, A., Bussotti, L., Szymanski, W., Jan Buma, W., Foggi, P., Di Donato, M. & Feringa, B. L. Tailoring Photoisomerization Pathways in Donor–Acceptor Stenhouse Adducts: The Role of the Hydroxy Group. J. Phys. Chem. A 122, 955–964 (2018). 18. Gomes, R. F. A., Coelho, J. A. S. & Afonso, C. A. M. Synthesis and Applications of Stenhouse Salts and Derivatives. Chem. Eur. J.24, 9170–9186 (2018). 19. Honda, K., Komizu, H. & Kawasaki, M. Reverse Photocharomism of Stenhouse Salts. J. Chem. Soc., Chem. Commun.253–254 (1982). 20. Lewis, K. G. & Mulquiney, C. E. Aspects of the Formation and Use of Stenhouse Salts and Related Compounds. Tetrahedron 33, 463–475 (1977). Attorney Docket No.11760-002WO1 21. Piancatelli, G., Scettri, A. & Barbadoro, S. A Useful Preparation of 4-Substituted 5- Hydroxy-3-Oxocyclopentene. Tetrahedron Lett.17, 3555–3558 (1976). 22. Veits, G. K., Wenz, D. R. & Read de Alaniz, J. Versatile Method for the Synthesis of 4- Aminocyclopentenones: Dysprosium(III) Triflate Catalyzed Aza-Piancatelli Rearrangement. Angew. Chem. Int. Ed.49, 9484–9487 (2010). 23. Palmer, L. I. & Read de Alaniz, J. Direct and Highly Diastereoselective Synthesis of Azaspirocycles by a Dysprosium(III) Triflate Catalyzed Aza-Piancatelli Rearrangement. Angew. Chem. Int. Ed.50, 7167–7170 (2011). 24. Šafař, P., Považanec, F., Pronayova, N., Baran, P., Kickelbick,G., Kožišek, J. & Breza, M. Dichotomy in the Ring Opening Reaction of 5-[(2-Furyl)methylidene]-2,2-dimethyl-1,3- dioxane-4,6-dione with Cyclic Secondary Amines. Collect. Czech. Chem. Commun.65, 1911– 1938 (2000). 25. Verrier, C.; Moebs-Sanchez, S.; Queneau, Y.; Popowycz, F. The Piancatelli Reaction and its Variants: Recent Applications to High Added-Value Chemicals and Biomass Valorization. Org. Biomol. Chem.16, 676–687 (2018). 26. Noirbent, G., Xu, Y., Bonardi, A.-H., Duval, S., Gigmes, D., Lalevee, J. & Dumur, F. New Donor-Acceptor Stenhouse Adducts as Visible and Near Infrared Light Polymerization Photoinitiators. Molecules 25, 2317 (2020). 27. Horner, K. E. & Karadakov, P. B. Chemical Bonding and Aromaticity in Furan, Pyrrole, and Thiophene: A Magnetic Shielding Study. J. Org. Chem.78, 8037–8043 (2013). 28. Najmidin, K., Kerim, A., Abdirishit, P., Kalam, H. & Tawar, T. A Comparative Study of the Aromaticity of Pyrrole, Furan, Thiophene, and their Aza-Derivatives. J. Mol. Model. 19, 3529–3535 (2013). 29. Palmer, L. I. & Read de Alaniz, J. Lewis Acid Catalyzed Rearrangement of Furylcarbinols: The Aza-and Oxa-Piancatelli Cascade Reaction. Synlett 25, 08–11 (2014). 30. Tsuruta, H., Yamaguchi, K. & Imamoto, T. Tandem Mass Spectrometric Analysis of Rare Earth(III) Complexes: Evaluation of the Relative Strength of their Lewis Acidity. Tetrahedron 59, 10419–10437 (2003). 31. Leboeuf, D., Marin, L., Michelet, B., Perez-Luna, A., Guillot, R., Schulz, E. & Gandon, V. Harnessing the Lewis Acidity of HFIP through its cooperation with a Calcium(II) Salt: Application to the Aza-Piancatelli Reaction. Chem. Eur. J.22, 16165–16171 (2016). Attorney Docket No.11760-002WO1 32. Clerc, M., Stricker, F., Ulrich, S., Sroda, M., Bruns, N., Boesel, L. F. & Read de Alaniz, J. Promoting the Furan Ring-Opening Reaction to Access New Donor–Acceptor Stenhouse Adducts with Hexafluoroisopropanol. Angew. Chem. Int. Ed.60, 10219–10227 (2021). 33. PhysChem Suite, Software V11.02, Advanced Chemistry Development, Inc (ACD/Labs), Toronto, ON, Canada, www.acdlabs.com. 34. Sroda, M. M., Stricker, F., Peterson, J. A., Bernal, A. & Read de Alaniz, J. Donor– Acceptor Stenhouse Adducts: Exploring the Effects of Ionic Character. Chem. Eur. J.27, 4183– 4190 (2020). 35. Muller, P. Glossary of Terms Used in Physical Organic Chemistry (IUPAC Recommendations 1994). Pure & Appl. Chem.66, 1077–1184 (1994). 36. Castagna, R., Maleeva, G., Pirovano, D., Matera, C. & Gorostiza, P. Donor–Acceptor Stenhouse Adduct Displaying Reversible Photoswitching in Water and Neuronal Activity. J. Am. Chem. Soc.144, 15595–15602 (2022). 37. Peterson, J. A., Neris, N. M. & Read de Alaniz, J. Tethered Together: DASA Design Towards Aqueous Compatibility. Chem. Sci.14, 13025–13030 (2023). The compositions and methods of the appended claims are not limited in scope by the specific compositions and methods described herein, which are intended as illustrations of a few aspects of the claims and any compositions and methods that are functionally equivalent are intended to fall within the scope of the claims. Various modifications of the compositions and methods in addition to those shown and described herein are intended to fall within the scope of the appended claims. Further, while only certain representative compositions and method steps disclosed herein are specifically described, other combinations of the compositions and method steps also are intended to fall within the scope of the appended claims, even if not specifically recited. Thus, a combination of steps, elements, components, or constituents may be explicitly mentioned herein; however, other combinations of steps, elements, components, and constituents are included, even though not explicitly stated.

Claims

Attorney Docket No.11760-002WO1 WHAT IS CLAIMED IS: 1. A photoresponsive compound of Formula I R2 X1 (I) wherein: D is a donor group; X¹ is -X²-H, wherein X² is selected from: ; R¹, R², and R³ are each independently selected from hydrogen, azido, halo, C1-C12 alkyl, C₁-C₁₂ haloalkyl, 6- to 10-membered monocyclic or bicyclic aryl, -OR⁵, and -SR⁵; X^2a is independently selected at each occurrence from O, NR⁴, and S; R^4a is independently selected at each occurrence from R⁴, -OR⁴, -SR⁴, and -N(R⁴)(R⁴); R⁴ and R⁵ are independently selected at each occurrence from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8- membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency; Y is independently selected at each occurrence from hydrogen, halo, nitro, cyano, azido, oxo, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C12 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C₀-C₃ alkyl)-, (6- to 10- membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^xO-(C₀-C₃ alkyl)-, R^xS-(C₀-C₃ alkyl)-, (R^xR^yN)-(C₀-C₃ alkyl)-, R^xO-C(O)-(C0-C3 alkyl)-, R^xS-C(O)-(C0-C3 alkyl)-, (R^xR^yN)C(O)-(C0-C3 alkyl)-, R^xO-S(O)₂-(C₀-C₃ alkyl)-, (R^xR^yN)S(O)₂-(C₀-C₃ alkyl)-, R^zC(O)-O-(C₀-C₃ alkyl)-, R^zC(O)- Attorney Docket No.11760-002WO1 (R^xN)-(C₀-C₃ alkyl)-, R^zS(O)₂-O-(C₀-C₃ alkyl)-, R^zS(O)₂-(R^xN)-(C₀-C₃ alkyl)-, R^zC(O)-(C₀- C₃ alkyl)-, R^zS(O)-(C₀-C₃ alkyl)-, and R^zS(O)₂-(C₀-C₃ alkyl)-; R^x and R^y are independently selected at each occurrence from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₇cycloalkyl)-(C₀-C₃ alkyl)-, (4- to 6- membered heterocycle)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic aryl)-(C0- C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-; and R^z is independently selected at each occurrence from hydrogen, halo, C1-C12 alkyl, C1-C12 haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₇cycloalkyl)-(C₀-C₃ alkyl)-, (4- to 6- membered heterocycle)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic aryl)-(C0- C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, -OR^x, -SR^x, and -NR^xR^y. 2. The photoresponsive compound of claim 1, wherein the compound is formed from a compound of Formula II: , wherein all variables are as 3. The photoresponsive compound of claim 2, wherein the carbon-13 nuclear magnetic resonance shift in deuterated chloroform of the carbon labeled * in Formula II is greater than about 111 ppm wherein * corresponds to a of attachment to the remainder of the compound of Formula II. 4. The photoresponsive compound of any one of claims 1-3, wherein X² is Attorney Docket No.11760-002WO1 . 5. The photoresponsive 1-4, wherein R⁴ is independently selected at each occurrence from 10-membered monocyclic or bicyclic aryl optionally substituted with one or more groups selected from Y as allowed by valency. 6. The photoresponsive compound of any one of claims 1-5, wherein the compound is of Formula I-a: . 7. The wherein D is selected from: ; wherein: R⁶ and R⁷ are independently selected from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C₂-C₁₂ alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)2-, and (R^xR^yN)S(O)2-, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency; or R⁶ and R⁷ are brought together with the carbon to which they are attached to form a 3- to 8- membered monocyclic or bicyclic heterocycle ring or a 5- to 10-membered monocyclic or bicyclic heteroaryl ring, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency; and R⁸ is selected from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)- (C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10- Attorney Docket No.11760-002WO1 membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^zC(O)-, R^zS(O)₂-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)₂-, and (R^xR^yN)S(O)₂-, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency. 8. The photoresponsive compound of claim 7, wherein D is . 9. The photoresponsive of claims 1-6, wherein D is selected from: , or bicyclic aryl, each of which may be optionally substituted with one or more Y groups as allowed by valency; R¹¹ and R¹² are independently selected at each occurrence from hydrogen, halo, nitro, cyano, azido, oxo, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C12 cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C₀-C₃ alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^xO-(C₀-C₃ alkyl)-, R^xS-(C₀-C₃ alkyl)-, (R^xR^yN)-(C0-C3 alkyl)-, R^xO-C(O)-(C0-C3 alkyl)-, R^xS-C(O)-(C0-C3 alkyl)-, (R^xR^yN)C(O)- (C₀-C₃ alkyl)-, R^xO-S(O)₂-(C₀-C₃ alkyl)-, (R^xR^yN)S(O)₂-(C₀-C₃ alkyl)-, R^zC(O)-O-(C₀-C₃ Attorney Docket No.11760-002WO1 alkyl)-, R^zC(O)-(R^xN)-(C₀-C₃ alkyl)-, R^zS(O)₂-O-(C₀-C₃ alkyl)-, R^zS(O)₂-(R^xN)-(C₀-C₃ alkyl)-, R^zC(O)-(C₀-C₃ alkyl)-, R^zS(O)-(C₀-C₃ alkyl)-, and R^zS(O)₂-(C₀-C₃ alkyl)-; m is an integer selected from 0 to 4; and X³ and X⁴ are independently selected from a bond, -CH₂-, -O-, and -NR¹³-, wherein R¹³ is selected from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3- C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C₀-C₃ alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^zC(O)-, R^zS(O)₂-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)2-, and (R^xR^yN)S(O)2-. 10. The photoresponsive compound of any one of claims 1-9, wherein A is selected from: X5 wherein: Z¹ and Z³ are independently selected from NR¹⁴ and O; Z² is a Z² is a to form arylene ring optionally substituted with one or more groups selected from Y; Z⁴ is selected from CR¹⁷ and N; X⁵, X⁶, and X⁷ are independently selected from O, S, or NR¹⁸; R¹³ is C1-C12 alkyl, C1-C12 haloalkyl, or 6- to 10-membered monocyclic or bicyclic aryl optionally substituted with one or more groups selected from Y; Attorney Docket No.11760-002WO1 R¹⁴ is independently selected at each occurrence from hydrogen, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8- membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)₂-, and (R^xR^yN)S(O)₂-; R¹⁵, R¹⁶, and R¹⁷ are independently selected from hydrogen, halo, nitro, cyano, azido, oxo, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₁₂ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10- membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^xO-(C0-C3 alkyl)-, R^xS-(C0-C3 alkyl)-, (R^xR^yN)-(C0-C3 alkyl)-, R^xO-C(O)-(C0-C3 alkyl)-, R^xS-C(O)-(C0-C3 alkyl)-, (R^xR^yN)C(O)-(C0-C3 alkyl)-, R^xO-S(O)2-(C0-C3 alkyl)-, (R^xR^yN)S(O)2-(C0-C3 alkyl)-, R^zC(O)-O-(C0-C3 alkyl)-, R^zC(O)- (R^xN)-(C0-C3 alkyl)-, R^zS(O)2-O-(C0-C3 alkyl)-, R^zS(O)2-(R^xN)-(C0-C3 alkyl)-, R^zC(O)-(C0- C3 alkyl)-, R^zS(O)-(C0-C3 alkyl)-, and R^zS(O)2-(C0-C3 alkyl)-; or R¹⁵ and R¹⁶ are brought together with the carbon to which they are attached to form a C3-C6 cycloalkyl ring or a 3- to 8-membered monocyclic or bicyclic heterocycle ring; R¹⁸ is independently selected at each occurrence from C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C₂-C₁₂ alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)2-, and (R^xR^yN)S(O)2-. 11. The photoresponsive compound of claim 10, wherein A is selected from: , Attorney Docket No.11760-002WO1 .

Attorney Docket No.11760-002WO1 . compound of Formula I, R2 X1 (I) the process comprising: reacting a compound of with a donor D-H to form Formula I; wherein: D is a donor group; X¹ is -X²-H, wherein X² is selected from: ; R¹, R², and R³ are each independently selected from hydrogen, azido, halo, C₁-C₁₂ alkyl, C1-C12 haloalkyl, 6- to 10-membered monocyclic or bicyclic aryl, -OR⁵, and -SR⁵; Attorney Docket No.11760-002WO1 X^2a is independently selected at each occurrence from O, NR⁴, and S; R^4a is independently selected at each occurrence from R⁴, -OR⁴, -SR⁴, and -N(R⁴)(R⁴); R⁴ and R⁵ are independently selected at each occurrence from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C6 cycloalkyl)(C0-C3 alkyl)-, (3- to 8- membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency; Y is independently selected at each occurrence from hydrogen, halo, nitro, cyano, azido, oxo, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C12 cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C₀-C₃ alkyl)-, (6- to 10- membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^xO-(C₀-C₃ alkyl)-, R^xS-(C₀-C₃ alkyl)-, (R^xR^yN)-(C₀-C₃ alkyl)-, R^xO-C(O)-(C0-C3 alkyl)-, R^xS-C(O)-(C0-C3 alkyl)-, (R^xR^yN)C(O)-(C0-C3 alkyl)-, R^xO-S(O)₂-(C₀-C₃ alkyl)-, (R^xR^yN)S(O)₂-(C₀-C₃ alkyl)-, R^zC(O)-O-(C₀-C₃ alkyl)-, R^zC(O)- (R^xN)-(C0-C3 alkyl)-, R^zS(O)2-O-(C0-C3 alkyl)-, R^zS(O)2-(R^xN)-(C0-C3 alkyl)-, R^zC(O)-(C0- C3 alkyl)-, R^zS(O)-(C0-C3 alkyl)-, and R^zS(O)2-(C0-C3 alkyl)-; R^x and R^y are independently selected at each occurrence from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C7cycloalkyl)-(C0-C3 alkyl)-, (4- to 6- membered heterocycle)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic aryl)-(C₀- C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-; and R^z is independently selected at each occurrence from hydrogen, halo, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C7cycloalkyl)-(C0-C3 alkyl)-, (4- to 6- membered heterocycle)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic aryl)-(C₀- C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, -OR^x, -SR^x, and -NR^xR^y. 14. The process of claim 13, further comprising preparing the compound of Formula II by a process comprising: reacting a compound of Formula III Attorney Docket No.11760-002WO1 with an acceptor H-A-H to 15. The process of carbon-13 nuclear magnetic resonance shift in deuterated chloroform of the carbon labeled * in Formula II is greater than about 111 ppm wherein * corresponds to a of attachment to the remainder of the compound of Formula II. 16. The process of any one of claims 13-15, wherein X² is . 17. The process of any one of R⁴ is independently selected at each occurrence from C1-C12 alkyl and 6- to 10-membered monocyclic or bicyclic aryl optionally substituted with one or more groups selected from Y as allowed by valency. 18. The process of any one of claims 13-17, wherein the compound is of Formula I-a: . Attorney Docket No.11760-002WO1 19. The process of any one of claims 13-18, wherein D-H is selected from: ; wherein: R⁶ and R⁷ are C1-C12 haloalkyl, C2-C12 alkenyl, C₂-C₁₂ alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)2-, and (R^xR^yN)S(O)2-, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency; or R⁶ and R⁷ are brought together with the carbon to which they are attached to form a 3- to 8- membered monocyclic or bicyclic heterocycle ring or a 5- to 10-membered monocyclic or bicyclic heteroaryl ring, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency; and R⁸ is selected from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)- (C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10- membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^zC(O)-, R^zS(O)₂-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)2-, and (R^xR^yN)S(O)2-, each of which may be optionally substituted with one or more groups selected from Y as allowed by valency. 20. The process of claim 19, wherein D-H is . 21. The process of any one of D-H is selected from: , Attorney Docket No.11760-002WO1 ; are to 10-membered monocyclic or bicyclic aryl, each of which may be optionally substituted with one or more Y groups as allowed by valency; R¹¹ and R¹² are independently selected at each occurrence from hydrogen, halo, nitro, cyano, azido, oxo, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₁₂ cycloalkyl)(C0-C3 alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^xO-(C0-C3 alkyl)-, R^xS-(C0-C3 alkyl)-, (R^xR^yN)-(C0-C3 alkyl)-, R^xO-C(O)-(C0-C3 alkyl)-, R^xS-C(O)-(C0-C3 alkyl)-, (R^xR^yN)C(O)- (C0-C3 alkyl)-, R^xO-S(O)2-(C0-C3 alkyl)-, (R^xR^yN)S(O)2-(C0-C3 alkyl)-, R^zC(O)-O-(C0-C3 alkyl)-, R^zC(O)-(R^xN)-(C0-C3 alkyl)-, R^zS(O)2-O-(C0-C3 alkyl)-, R^zS(O)2-(R^xN)-(C0-C3 alkyl)-, R^zC(O)-(C0-C3 alkyl)-, R^zS(O)-(C0-C3 alkyl)-, and R^zS(O)2-(C0-C3 alkyl)-; m is an integer selected from 0 to 4; and X³ and X⁴ are independently selected from a bond, -CH₂-, -O-, and -NR¹³-, wherein R¹³ is selected from hydrogen, C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)- (C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10- membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^zC(O)-, R^zS(O)₂-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)2-, and (R^xR^yN)S(O)2-. 22. The process of any one of claims 13-21, wherein A is selected from: Attorney Docket No.11760-002WO1 X5 wherein: Z¹ and Z³ are independently Z² is a Z² is a to form arylene ring optionally substituted with one or more groups selected from Y; Z⁴ is selected from CR¹⁷ and N; X⁵, X⁶, and X⁷ are independently selected from O, S, or NR¹⁸; R¹³ is C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, or 6- to 10-membered monocyclic or bicyclic aryl optionally substituted with one or more groups selected from Y; R¹⁴ is independently selected at each occurrence from hydrogen, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C6 cycloalkyl)(C0-C3 alkyl)-, (3- to 8- membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO- S(O)2-, and (R^xR^yN)S(O)2-; R¹⁵, R¹⁶, and R¹⁷ are independently selected from hydrogen, halo, nitro, cyano, azido, oxo, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₁₂ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10- membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^xO-(C0-C3 alkyl)-, R^xS-(C0-C3 alkyl)-, (R^xR^yN)-(C0-C3 Attorney Docket No.11760-002WO1 alkyl)-, R^xO-C(O)-(C₀-C₃ alkyl)-, R^xS-C(O)-(C₀-C₃ alkyl)-, (R^xR^yN)C(O)-(C₀-C₃ alkyl)-, R^xO-S(O)₂-(C₀-C₃ alkyl)-, (R^xR^yN)S(O)₂-(C₀-C₃ alkyl)-, R^zC(O)-O-(C₀-C₃ alkyl)-, R^zC(O)- (R^xN)-(C0-C3 alkyl)-, R^zS(O)2-O-(C0-C3 alkyl)-, R^zS(O)2-(R^xN)-(C0-C3 alkyl)-, R^zC(O)-(C0- C₃ alkyl)-, R^zS(O)-(C₀-C₃ alkyl)-, and R^zS(O)₂-(C₀-C₃ alkyl)-; or R¹⁵ and R¹⁶ are brought together with the carbon to which they are attached to form a C3-C6 cycloalkyl ring or a 3- to 8-membered monocyclic or bicyclic heterocycle ring; R¹⁸ is independently selected at each occurrence from C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C₂-C₁₂ alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)2-, and (R^xR^yN)S(O)2-. 23. The process of claim 22, wherein A is selected from: . Attorney Docket No.11760-002WO1 wherein: Z¹ and Z³ are independently to form arylene ring optionally substituted with one or more groups selected from Y; Z⁴ is selected from CR¹⁷ and N; X⁵, X⁶, and X⁷ are independently selected from O, S, or NR¹⁸; R¹³ is C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, or 6- to 10-membered monocyclic or bicyclic aryl optionally substituted with one or more groups selected from Y; R¹⁴ is independently selected at each occurrence from hydrogen, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C2-C12 alkenyl, C2-C12 alkynyl, (C3-C6 cycloalkyl)(C0-C3 alkyl)-, (3- to 8- membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)2-, and (R^xR^yN)S(O)2-; R¹⁵, R¹⁶, and R¹⁷ are independently selected from hydrogen, halo, nitro, cyano, azido, oxo, C₁-C₁₂ alkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ alkenyl, C₂-C₁₂ alkynyl, (C₃-C₁₂ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10- membered monocyclic or bicyclic aryl)-(C₀-C₃ alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C0-C3 alkyl)-, R^xO-(C0-C3 alkyl)-, R^xS-(C0-C3 alkyl)-, (R^xR^yN)-(C0-C3 Attorney Docket No.11760-002WO1 alkyl)-, R^xO-C(O)-(C₀-C₃ alkyl)-, R^xS-C(O)-(C₀-C₃ alkyl)-, (R^xR^yN)C(O)-(C₀-C₃ alkyl)-, R^xO-S(O)₂-(C₀-C₃ alkyl)-, (R^xR^yN)S(O)₂-(C₀-C₃ alkyl)-, R^zC(O)-O-(C₀-C₃ alkyl)-, R^zC(O)- (R^xN)-(C0-C3 alkyl)-, R^zS(O)2-O-(C0-C3 alkyl)-, R^zS(O)2-(R^xN)-(C0-C3 alkyl)-, R^zC(O)-(C0- C₃ alkyl)-, R^zS(O)-(C₀-C₃ alkyl)-, and R^zS(O)₂-(C₀-C₃ alkyl)-; or R¹⁵ and R¹⁶ are brought together with the carbon to which they are attached to form a C3-C6 cycloalkyl ring or a 3- to 8-membered monocyclic or bicyclic heterocycle ring; R¹⁸ is independently selected at each occurrence from C1-C12 alkyl, C1-C12 haloalkyl, C2-C12 alkenyl, C₂-C₁₂ alkynyl, (C₃-C₆ cycloalkyl)(C₀-C₃ alkyl)-, (3- to 8-membered monocyclic or bicyclic heterocycle)-(C0-C3 alkyl)-, (6- to 10-membered monocyclic or bicyclic aryl)-(C0-C3 alkyl)-, (5- to 10-membered monocyclic or bicyclic heteroaryl)-(C₀-C₃ alkyl)-, R^zC(O)-, R^zS(O)2-, R^xO-C(O)-, R^xS-C(O)-, (R^xR^yN)C(O)-, R^xO-S(O)2-, and (R^xR^yN)S(O)2-. 25. The process of claim 24, wherein H-A-H is selected from: . 25. Attorney Docket No.11760-002WO1 27. A method for changing the color of a material, wherein the material comprises a photoresponsive compound of any one of claims 1-12, the method comprising: irradiating the material with light of a first wavelength, whereupon irradiation with the light, the photoresponsive compound converts into a compound of Formula III: wherein all variables are as 1-12. 28. A photo-responsive a responsive phase-tag system, pigment, a tattoo pigment, a cosmetic pigment, a data storage system, a re-writable system, a sensor, an electronic system, an energy storage system, a gas uptake and release system, a nanoreactor, a cell mimic, a liquid crystal display, an optical storage system, a photo- pharmacology system, a self-healing material, a polymer phase chemistry system, a wave- selective photo-sensing system, or a photochromic lens comprising a photoresponsive compound of any one of claims 1-12 and 26. 29. The photoresponsive compound of any one of claims 1-12 and 26, wherein the photoresponsive compound is for use in a photo-responsive drug delivery system, a photo- responsive phase-tag system, pigment, a tattoo pigment, a cosmetic pigment, a data storage system, a re-writable system, a sensor, an electronic system, an energy storage system, a gas uptake and release system, a nanoreactor, a cell mimic, a liquid crystal display, an optical storage system, a photo-pharmacology system, a self-healing material, a polymer phase chemistry system, a wave-selective photo-sensing system, or a photochromic lens.