CN117715916A

CN117715916A - Light-responsive non-fullerene receptor of a-D-a' -D-a type for use in optoelectronic devices

Info

Publication number: CN117715916A
Application number: CN202280051033.1A
Authority: CN
Inventors: M·马赛杰克兹克; N·雅可比-格罗斯
Original assignee: Sumitomo Chemical Co Ltd
Current assignee: Sumitomo Chemical Co Ltd
Priority date: 2021-08-06
Filing date: 2022-08-05
Publication date: 2024-03-15
Also published as: CN117693510A; CN117813310A; CN117715917A

Abstract

The present disclosure provides a compound of formula (I), A1 is a divalent heteroaromatic electron accepting group; a is that ² And A ³ Each independently is a monovalent electron accepting group; d (D) ¹ And D ² Independently at each occurrence an electron donating group; b (B) ¹ And B ² Independently at each occurrence a bridging group; x is x ¹ And x ² Each independently 0, 1, 2 or 3; y is ¹ And y ² Each independently is at least 1; and z ¹ And z ² Each independently 0, 1, 2 or 3, provided that z ¹ And z ² At least one of which is at least 1. The compounds of formula (I) may be used as electron accepting materials in organic photodetectors.

Description

Light-responsive non-fullerene receptor of a-D-a' -D-a type for use in optoelectronic devices

Background

Embodiments of the present disclosure relate to electron-accepting compounds, and more particularly, but not by way of limitation, to compounds containing electron-accepting and electron-donating units that are suitable for use as electron-accepting materials in light-responsive devices.

Electron accepting non-fullerene compounds are known.

Yoon et al, "Effects of Electron Donating and Electron-Accepting Substitution on Photovoltaic Performance in Benzothiadiazole-Based A-D-A '-D-A-Type Small-Molecule Acceptor Solar Cells" ACS appl.energy Mater.2020,3,12,12327-12337 discloses A-D-A' -D-A Type receptors for use in solar cells.

Gao et al, "Non-fullerene acceptors with nitrogen-containing six-membered heterocycle cores for the applications in organic solar cells" Solar Energy Materials and Solar Cells 225,2021,111046 disclose Non-fullerene receptors having pyrazine or pyridazine as a core.

Wang et al, "Near-infrared absorbing non-fullerene acceptors with unfused D-A-Dcore for efficient organic solar cells" Organic Electronics 92,2021,106131 discloses the use of 3-bis (4- (2-ethylhexyl) -thiophen-2-yl) -5, 7-bis (2-ethylhexyl) benzo- [1,2:4,5-c '] -dithiophene-4, 8-dione (BDD) units as part A and 4, 4-dialkyl-4H-cyclopenta [2,1-b:3,4-b' ] dithiophene (CPDT) units as part D-A-D cores.

CN110379926 discloses an organic solar cell based on a near infrared receptor of benzodithiazole.

CN112608333 discloses a small molecule based on a dithiadiazole carbazole derivative.

CN112259687 discloses a ternary fullerene organic solar cell.

Disclosure of Invention

In some embodiments, the present disclosure provides a compound of formula (I):

wherein:

A ¹ is a divalent heteroaromatic electron accepting group;

A ² And A ³ Each independently is a monovalent electron accepting group;

D ¹ and D ² Independently at each occurrence an electron donating group;

B ¹ and B ² Independently at each occurrence a bridging group;

x ¹ and x ² Each independently 0, 1, 2 or 3;

y ¹ and y ² Each independently is at least 1; and is also provided with

z ¹ And z ² Each independently 0, 1, 2 or 3,

provided that z is ¹ And z ² At least one of which is at least 1.

In some embodiments, the present disclosure provides a compound of formula (I):

wherein:

A ¹ a divalent heteroaromatic electron accepting group comprising at least 3 fused rings;

A ² and A ³ Each independently is a monovalent electron accepting group;

D ¹ and D ² Independently at each occurrence an electron donating group;

B ¹ and B ² Independently at each occurrence a bridging group;

x ¹ and x ² Each independently 0, 1, 2 or 3;

y ¹ and y ² Each independently is at least 1; and is also provided with

z ¹ And z ² Each independently 0, 1, 2 or 3,

provided that x is ¹ 、x ² 、z ¹ And z ² At least one of which is at least 1.

Drawings

The disclosed technology and the figures describe some implementations of the disclosed technology.

FIG. 1 depicts an organic light responsive device according to some embodiments;

FIG. 2 shows absorption spectra of compounds and unbridged comparative compounds according to an embodiment of the disclosure;

FIG. 3 illustrates external quantum efficiency versus wavelength for an organic photodetector containing a compound according to an embodiment of the present disclosure and an organic photodetector containing an unbridged comparative compound; and is also provided with

Fig. 4 shows dark current density and voltage for the device of fig. 3.

The figures are not drawn to scale and have different viewpoints and angles of view. The drawings are some implementations and examples. Additionally, for the purposes of discussing some embodiments of the disclosed technology, some components and/or operations may be divided into different blocks or combined into a single block. Further, while the technology is susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and are described in detail below. However, the intent is not to limit the technique to the particular implementation described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the technical scope defined by the appended claims.

Detailed Description

Throughout the specification and claims, the words "comprise", "comprising", and the like are to be interpreted in an inclusive rather than an exclusive or exhaustive sense unless the context clearly requires otherwise; that is, in the sense of "including but not limited to". In addition, as used in this application, the words "herein," "above," "below," and words of similar import refer to this application as a whole and not to any particular portions of this application. Words in the detailed description using the singular or plural number may also include the plural or singular number, respectively, where the context allows. The word "or" in relation to a list of two or more items encompasses all of the following interpretations of the word: any item in the list, all items in the list, and any combination of items in the list. As used in this application, reference to a layer "on top of another layer" means that the layers may be in direct contact or that one or more intervening layers may be present. As used in this application, reference to a layer "on another layer" means that the layers are in direct contact. Unless explicitly stated otherwise, reference to a particular atom includes any isotope of that atom.

The teachings of the technology provided herein may be applied to other systems and not necessarily to the systems described below. The elements and acts of the various examples described below may be combined to provide further implementations of the technology. Some alternative implementations of the technology may include not only additional elements to those implementations mentioned below, but may include fewer elements.

These and other changes can be made to the technology in light of the detailed description below. While this specification describes certain examples of the technology, and describes the best mode contemplated, no matter how detailed this specification appears, the technology can be practiced in many ways. As noted above, particular terminology used in describing certain features or aspects of the present technology should not be taken to imply that the terminology is being redefined herein to be restricted to any specific characteristics, features, or aspects of the technology with which that terminology is associated. In general, the terms used in the following claims should not be construed to limit the technology to the specific examples disclosed in the specification unless the detailed description section explicitly defines such terms. Therefore, the actual scope of the technology encompasses not only the disclosed examples, but also all equivalent ways of practicing or implementing the technology under the claims.

In order to reduce the number of claims, certain aspects of the technology are presented below in certain claim forms, but applicant envisions various aspects of the technology in any number of claim forms.

In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the implementations of the disclosed technology. It will be apparent, however, to one skilled in the art that embodiments of the disclosed technology may be practiced without some of these specific details.

The compounds of formula (I) as described herein may be provided in a bulk heterojunction layer of a light responsive device, preferably a photodetector, wherein the bulk heterojunction layer is disposed between an anode and a cathode.

The bulk heterojunction layer comprises or consists of an electron donating material as described herein and an electron accepting compound of formula (I).

In some embodiments, the bulk heterojunction layer contains two or more acceptor materials and/or two or more electron acceptor materials.

In some embodiments, the weight ratio of electron donating material to electron accepting material is about 1:0.5 to about 1:2, preferably about 1:1.1 to about 1:2.

Preferably, the electron donating material has a type II interface with the electron accepting material, i.e., the HOMO and LUMO energy levels of the electron donating material are shallower than the corresponding HOMO and LUMO energy levels of the electron accepting material. Preferably, the HOMO level of the compound of formula (I) is at least 0.05eV deeper than the HOMO of the electron donating material, optionally at least 0.10eV deeper.

Optionally, the energy gap between the HOMO level of the electron donating material and the LUMO level of the electron accepting compound of formula (I) is less than 1.4eV.

The HOMO and LUMO energy levels of the materials described herein are measured by Square Wave Voltammetry (SWV), unless otherwise indicated.

In SWV, the current at the working electrode is measured while the potential between the working electrode and the reference electrode is scanned linearly in time. The current difference between the forward and reverse pulses is plotted as a function of the potential to produce a voltammogram. The measurement may be performed with a CHI 660D potentiostat.

The apparatus for measuring HOMO or LUMO energy levels by SWV may comprise a cell containing 0.1M t-butylammonium hexafluorophosphate in acetonitrile; a glassy carbon working electrode having a diameter of 3 mm; a platinum counter electrode and a leak-free Ag/AgCl reference electrode.

Ferrocene was added directly to an existing cell at the end of the experiment for calculation purposes, where the potential of ferrocene for oxidation and reduction relative to Ag/AgCl was measured using Cyclic Voltammetry (CV).

The sample was dissolved in toluene (3 mg/ml) and spun directly onto the glassy carbon working electrode at 3000 rpm.

lumo=4.8-E ferrocene (peak-to-peak average) -E reduction of sample (peak maximum).

homo=4.8-E ferrocene (peak-to-peak average) +e oxidation of sample (peak maximum).

Typical SWV experiments were performed at a frequency of 15 Hz; 25mV amplitude and 0.004V increment step size. Results were calculated from 3 new spin film samples for HOMO and LUMO data.

Preferably, the compounds of formula (I) have an absorption peak of more than 1000nm, more preferably more than 1100nm or 1200 nm.

The absorbance spectra of the materials described herein were measured using a Cary 5000UV-VIS-NIR spectrometer, unless otherwise indicated. Measurements were made in the 300nm to 2500nm range using a PbSmart NIR detector with variable slit width (as low as 0.01 nm) extended photometric range for optimal control of data resolution.

Absorption data is obtained by measuring the intensity of transmitted radiation transmitted through a sample of the solution. The absorption intensity is plotted against the incident wavelength to generate an absorption spectrum. Solution absorption can be measured from a 0.015mg/ml solution in a quartz cuvette and compared to a cuvette containing only solvent.

In some embodiments, the electron accepting compound has formula (I):

D ¹ and D ² Independently at each occurrence an electron donating group.

A ¹ 、A ² And A ³ Each independently is an electron accepting group.

B ¹ And B ² Independently at each occurrence a bridging group.

x ¹ And x ² Each independently is 0, 1, 2 or 3, preferably 0 or 1.

y ¹ And y ² Each independently is at least 1, preferably 1, 2 or 3, more preferably 1.

z ¹ And z ² Each independently is 0, 1, 2 or 3, preferably 1.

Electron accepting group A ¹ 、A ² And A ³ The Lowest Unoccupied Molecular Orbital (LUMO) energy level of each of (a) is higher than that of electron donating group D ¹ Or D ² Either of which is deep (i.e., farther from the vacuum level), preferably at least 1eV deep. The LUMO energy levels of the electron accepting and donating groups can be determined by modeling the LUMO energy levels of these groups, with each bond to an adjacent group being replaced by a bond to a hydrogen atom. Gaussian09 software available from Gaussian (Gaussian) can be used to model using Gaussian09 with B3LYP (functional) and LACVP (basis set).

Preferably, A ¹ Comprising at least 3 fused rings.

¹ Acceptor unit A

A ¹ May be a polycyclic heteroaromatic group which is unsubstituted or substituted with one or more substituents.

Formula (I)) Is a preferred group A of (2) ¹ Is a group of formula (II):

wherein:

Ar ¹ is a monocyclic or polycyclic aromatic or heteroaromatic group; and is also provided with

Y is O, S, NR ⁴ Or R is ¹ -C＝C-R ¹ Wherein R is ¹ Independently at each occurrence H or a substituent, wherein two substituents R ¹ May be linked to form a single ring or multiple rings; and R is ⁴ Is H or a substituent.

R ² A group, wherein R is ² Independently at each occurrence a substituent.

Preferred R ² The radicals being selected from

F；

CN；

NO ₂ ；

C _1-20 Alkyl groups in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ Replacement, wherein R ⁷ Is C _1-12 A hydrocarbyl group, COO, or CO, and one or more H atoms of the alkyl group may be replaced with F;

an aromatic or heteroaromatic group, preferably phenyl, which is unsubstituted or substituted with one or more substituents; a group selected from:

wherein Z is ⁴⁰ 、Z ⁴¹ 、Z ⁴² And Z ⁴³ Each independently is CR ¹³ Or N, wherein R ¹³ At each occurrence is H or a substituent, preferably C _1-20 A hydrocarbyl group; y is Y ⁴⁰ And Y ⁴¹ Each independently O, S, NX ⁷¹ Wherein X is ⁷¹ Is CN or COOR ⁴⁰ The method comprises the steps of carrying out a first treatment on the surface of the Or CX (CX) ⁶⁰ X ⁶¹ Wherein X is ⁶⁰ And X ⁶¹ Independently and separatelyIs CN, CF ₃ Or COOR ⁴⁰ ；W ⁴⁰ And W is ⁴¹ Each independently O, S, NX ⁷¹ Or CX (CX) ⁶⁰ X ⁶¹ Wherein X is ⁶⁰ And X ⁶¹ Independently CN, CF ₃ Or COOR ⁴⁰ The method comprises the steps of carrying out a first treatment on the surface of the And R is ⁴⁰ At each occurrence is H or a substituent, preferably H or C _1-20 A hydrocarbyl group. Exemplary substituents R for aromatic or heteroaromatic groups ² Is F, CN, NO ₂ And C _1-12 Alkyl groups in which one or more non-adjacent C atoms may be replaced by O, S, NR ⁷ COO or CO, and one or more H atoms of the alkyl group may be replaced by F.

R as described anywhere herein ⁷ May be, for example, C _1-12 Alkyl, unsubstituted phenyl, or substituted with one or more C _1-6 Phenyl substituted with an alkyl group.

If the C atom of an alkyl group as described anywhere herein is replaced with another atom or group, the C atom that is replaced may be a terminal C atom or a non-terminal C atom of the alkyl group.

As used anywhere herein, "non-terminal C atom" of an alkyl group means a C atom other than the C atom of a methyl group at the end of an n-alkyl chain or the C atom of a methyl group at the end of a branched alkyl chain.

If the terminal C atom of a group as described anywhere herein is replaced, the resulting group may be an anionic group comprising a counter cation (e.g., an ammonium or metal counter cation, preferably an ammonium or alkali metal cation).

The C atom of an alkyl substituent substituted with another atom or group as described anywhere herein is preferably a non-terminal C atom, and the resulting substituent group is preferably nonionic.

Exemplary monocyclic heteroaromatic group Ar ¹ Is oxadiazole, thiadiazole, triazole and 1, 4-diazine, which is unsubstituted or substituted with one or more substituents. Thiadiazoles are particularly preferred.

Exemplary polycyclic heteroaromatic groups Ar ¹ Is a group of formula (V):

X ¹ and X ² Each independently selected from N and CR ³ Wherein R is ³ Is H or a substituent, optionally H or a substituent R as described above ² 。

X ³ 、X ⁴ 、X ⁵ And X ⁶ Each independently selected from N and CR ³ Provided that X ³ 、X ⁴ 、X ⁵ And X ⁶ At least one of them is CR ³ 。

Z is selected from O, S, SO ₂ 、NR ⁴ 、PR ⁴ 、C(R ³ ) ₂ 、Si(R ³ ) ₂ C= O, C =s and c=c (R ⁵ ) ₂ Wherein R is ³ As described above; r is R ⁴ Is H or a substituent; and R is ⁵ At each occurrence is an electron withdrawing group.

Optionally, any NR described anywhere herein ⁴ Or PR (PR) ⁴ Each R of (2) ⁴ Independently selected from H; c (C) _1-20 Alkyl groups, one or more non-adjacent C atoms other than the C atom bonded to N or P may be O, S, NR ⁷ COO or CO, and one or more H atoms of the alkyl group may be replaced by F; and phenyl, which is unsubstituted or substituted with one or more substituents, optionally one or more C _1-12 Alkyl substituted wherein one or more non-adjacent C atoms of the alkyl group may be substituted with O, S, NR ⁷ COO or CO, and one or more H atoms of the alkyl group may be replaced by F.

Preferably, each R ⁵ Is CN, COOR ⁴⁰ The method comprises the steps of carrying out a first treatment on the surface of the Or CX (CX) ⁶⁰ X ⁶¹ Wherein X is ⁶⁰ And X ⁶¹ Independently CN, CF ₃ Or COOR ⁴⁰ And R is ⁴⁰ At each occurrence is H or a substituent, preferably H or C _1-20 A hydrocarbyl group.

A of the formula (II) ¹ The group is preferably selected from the group of formulae (IIa) and (IIb):

for the compound of formula (IIb), two R ¹ The groups may or may not be attached.

Preferably, when two R' s ¹ When the radicals are not attached, each R ¹ Independently selected from H; f, performing the process; a CN; NO (NO) ₂ ；C _1-20 Alkyl groups in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ 、CO、COO、NR ⁴ 、PR ⁴ Or Si (R) ³ ) ₂ Replacement, wherein R ³ And R is ⁴ As described above, and one or more H atoms may be replaced by F; and aryl or heteroaryl, preferably phenyl, which may be unsubstituted or substituted with one or more substituents. Substituents for aryl or heteroaryl groups may be selected from F; a CN; NO (NO) ₂ The method comprises the steps of carrying out a first treatment on the surface of the C _1-20 Alkyl groups in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ CO, COO, and one or more H atoms may be replaced with F.

Preferably, when two R' s ¹ When the groups are linked, the group of formula (IIb) has the formula (IIb-1) or (IIb-2):

Ar ² is an aromatic or heteroaromatic group, preferably benzene, which is unsubstituted or substituted with one or more substituents. Ar (Ar) ² May be unsubstituted or substituted by one or more substituents R as described above ² And (3) substitution.

X is selected from O, S, SO ₂ 、NR ⁴ 、PR ⁴ 、C(R ³ ) ₂ 、Si(R ³ ) ₂ C= O, C =s and c=c (R ⁵ ) ₂ Wherein R is ³ 、R ⁴ And R is ⁵ As described above.

Exemplary electron accepting groups of formula (II) include, but are not limited to:

Wherein Ak is ¹ Is C _1-20 Alkyl group

The divalent electron accepting groups other than formula (II) are optionally selected from formulas (IVa) to (IVj):

R ²³ at each occurrence is a substituent, optionally C _1-12 Alkyl, wherein is not attached to Z ¹ One or more non-adjacent C atoms other than C atoms of (C) may be O, S, NR ⁷ COO or CO, and one or more H atoms of the alkyl group may be replaced by F.

R ²⁵ Independently at each occurrence H; f, performing the process; a CN; NO (NO) ₂ ；C _1-12 Alkyl groups in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ COO or CO, and one or more H atoms of the alkyl group may be replaced by F; or an aromatic group, optionally phenyl, which is unsubstituted or selected from F and C _1-12 One or more substituents of the alkyl group, wherein one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ Replacement of COO or CO; or (b)

Wherein Z is ⁴⁰ 、Z ⁴¹ 、Z ⁴² And Z ⁴³ Each independently is CR ¹³ Or N, wherein R ¹³ At each occurrence is H or a substituent, preferably C _1-20 A hydrocarbyl group;

Y ⁴⁰ and Y ⁴¹ Each independently O, S, NX ⁷¹ Wherein X is ⁷¹ Is CN or COOR ⁴⁰ The method comprises the steps of carrying out a first treatment on the surface of the Or CX (CX) ⁶⁰ X ⁶¹ Wherein X is ⁶⁰ And X ⁶¹ Independently CN, CF ₃ Or COOR ⁴⁰ ；

W ⁴⁰ And W is ⁴¹ Each independently O, S, NX ⁷¹ Wherein X is ⁷¹ Is CN or COOR ⁴⁰ The method comprises the steps of carrying out a first treatment on the surface of the Or CX (CX) ⁶⁰ X ⁶¹ Wherein X is ⁶⁰ And X ⁶¹ Independently CN, CF ₃ Or COOR ⁴⁰ The method comprises the steps of carrying out a first treatment on the surface of the And is also provided with

R ⁴⁰ At each occurrence is H or a substituent, preferably H or C _1-20 A hydrocarbyl group.

Z ¹ Is N or P.

T ¹ 、T ² And T ³ Each independently represents an aryl or heteroaryl ring which may be fused with one or more additional rings, optionally benzene. In the presence of T ¹ 、T ² And T ³ Optionally selected from R ²⁵ Is a non-H group.

R ¹² At each occurrence is a substituent, preferably C _1-20 A hydrocarbon group.

Ar ⁵ Is arylene or heteroarylene, optionally thiophene, fluorene or phenylene, which may be unsubstituted or substituted with one or more substituents, optionally one or more substituents selected from R ²⁵ Is substituted with a non-H group.

² ³ Electron accepting groups A and A

Monovalent acceptor group A ² And A ³ Each independently selected from any such unit known to those skilled in the art. A is that ² And A ³ May be the same or different, preferably the same.

Exemplary monovalent acceptor units include, but are not limited to, units of formulas (IIIa) to (IIIq)

/>

U is a 5-or 6-membered ring, which is unsubstituted or substituted with one or more substituents and which may be fused to one or more additional rings.

The N atom of formula (IIIe) may be unsubstituted or substituted.

R ¹⁰ Is H or a substituent, preferably a substituent selected from the group consisting of: c (C) _1-12 Alkyl groups in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ COO or CO, and one or more H atoms of the alkyl group may be replaced by F; and an aromatic group, optionally phenyl, which is unsubstituted or selected from F and C _1-12 One or more substituents of the alkyl group, wherein one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ COO or CO substitution.

Preferably, R ¹⁰ H.

J is O or S, preferably O.

R ¹³ At each occurrence is a substituent, optionally C _1-12 Alkyl groups in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ COO or CO, and one or more H atoms of the alkyl group may be replaced by F.

R ¹⁵ Independently at each occurrence H; f, performing the process; c (C) _1-12 Alkyl groups in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ COO or CO, and one or more H atoms of the alkyl group may be replaced by F; aromatic group Ar ² Optionally phenyl, which is unsubstituted or selected from F and C _1-12 One or more substituents of the alkyl groupSubstituted, wherein one or more non-adjacent C atoms may be replaced by O, S, NR ⁷ Replacement of COO or CO; or a group selected from:

R ¹⁶ is H or a substituent, preferably selected from the following:

–(Ar ³ ) _w wherein Ar is ³ Independently at each occurrence is an unsubstituted or substituted aryl or heteroaryl group, preferably thiophene, and w is 1, 2 or 3;

and

C _1-12 Alkyl groups in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ COO or CO, and one or more H atoms of the alkyl group may be replaced by F.

Ar ⁶ Is a 5 membered heteroaromatic group, preferably thiophene or furan, which is unsubstituted or substituted with one or more substituents.

Ar ³ And Ar is a group ⁶ Optionally selected from C _1-12 Alkyl groups in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ COO or CO, and one or more H atoms may be replaced by F.

T ¹ 、T ² And T ³ Each independently as described above.

Ar ⁸ Is a fused heteroaromatic group which is unsubstituted or substituted with one or more substituents, optionally one or more non-H substituents R ¹⁰ Substituted, and it is bonded to B ² And is bonded to B ² Boron substituents of (a).

Preferred groups A ² And A ³ Is a group having a non-aromatic carbon-carbon bond directly bonded to D ¹ Or D ² Or if present, to B ² 。

Preferably, A ² And A ³ At least one of, preferably A ² And A ³ Both are groups of formula (IIIa-1):

wherein:

R ¹⁰ As described above;

each X is ⁷ To X ¹⁰ Independently CR ¹² Or N, wherein R ¹² At each occurrence H or selected from C _1-20 Substituents for hydrocarbyl and electron withdrawing groups. Preferably, the electron withdrawing group is F, cl, br or CN, more preferably F, cl or CN; and is also provided with

X ⁶⁰ And X ⁶¹ Independently CN, CF ₃ Or COOR ⁴⁰ Wherein R is ⁴⁰ At each occurrence is H or a substituent, preferably H or C _1-20 A hydrocarbyl group. Preferably X ⁶⁰ And X ⁶¹ Each is CN.

C _1-20 Hydrocarbyl group R ¹² Can be selected from C _1-20 An alkyl group; unsubstituted phenyl; and via one or more C _1-12 Phenyl substituted with an alkyl group.

Exemplary groups of formula (IIId) include:

exemplary groups of formula (IIIe) include:

exemplary groups of formula (IIIq) are:

exemplary groups of formula (IIIg) are:

exemplary groups of formula (IIIj) are:

wherein Ak is C _1-12 Alkylene chains in which one or more C atoms may be replaced by O, S, NR ⁷ Substitution of CO or COO; an is An anion, optionally-SO ₃ ^- The method comprises the steps of carrying out a first treatment on the surface of the And each benzene ring is independently unsubstituted or selected from reference R ¹⁰ One or more substituents of the described substituents are substituted.

Exemplary groups of formula (IIIm) are:

exemplary groups of formula (IIIn) are:

the radical of formula (IIIo) being directly bonded to the radical of formula (B) (R ¹⁴ ) ₂ Substituted bridging group B ² Wherein R is ¹⁴ At each occurrence is a substituent, optionally C _1-20 A hydrocarbon group; and R is ³ Or R is ⁶ B (R) ¹⁴ ) ₂ Is a bond to (a); and- -is with B ² Is a key of (c).

Optionally R ¹⁴ Selected from C _1-12 An alkyl group; unsubstituted phenyl; and via one or more C _1-12 Phenyl substituted with an alkyl group.

A group of formula (IIIo), B ² Radicals and B ² B (R) ¹⁴ ) ₂ Substituents may be linked together to form a 5-membered ring or a 6-membered ring.

Optionally, the group of formula (IIIo) is selected from:

bridging unit

Bridging unit B ¹ And B ² Preferably each is selected from the group consisting of vinylidene, arylene, heteroarylene, arylene vinylene, and heteroarylene vinylene, wherein arylene and heteroarylene are monocyclic or bicyclic groups, each of which may be unsubstituted or substituted with one or more substituents.

Bridging unit B ¹ And B ² Preferably a monocyclic or fused bicyclic arylene or heteroarylene group, more preferably a monocyclic or fused bicyclic heteroarylene group.

If x ¹ And x ² Each is at least 1, then each B ¹ Preferably identical.

If z ¹ And z ² Each is at least 1, then each B ² Preferably identical.

Optionally, B ¹ And B ² Units independently selected from formulas (VIa) to (VIn):

wherein R is ⁵⁵ Is H or a substituent; r is R ⁸ Each occurrence is independently H or a substituent, preferably H or a substituent selected from the group consisting of: f, performing the process; a CN; NO (NO) ₂ ；C _1-20 Alkyl groups in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ COO or CO, and one or more H atoms of the alkyl group may be replaced by F; phenyl, which is unsubstituted or substituted with one or more substituents; -B (R) ¹⁴ ) ₂ Wherein R is ¹⁴ At each timeIndependently at the occurrence is a substituent, optionally C _1-20 A hydrocarbyl group. R of formulae (VIa), (VIb) and (VIc) ⁸ The groups may be linked to form a bicyclic ring, such as thienopyrazine.

R ⁸ Preferably H, C _1-20 Alkyl, -COO-C _1-19 Alkyl, C _1-19 Alkoxy or C _1-19 Thioalkyl groups.

¹ ² Electron donating groups D and D

The electron donating group is preferably a fused aromatic or heteroaromatic group, more preferably a fused heteroaromatic group containing 3 or more rings. Particularly preferred electron donating groups include fused thiophene or furan rings, optionally containing thiophene or furan rings and one or more rings selected from benzene, cyclopentadiene, tetrahydropyran, tetrahydrothiopyran, and piperidine rings, each of which is unsubstituted or substituted with one or more substituents.

D ¹ And D ² May be the same or different. Preferably, they are identical.

Exemplary electron donating groups D ¹ And D ² Comprising groups of formulae (VIIa) to (VIIP):

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wherein Y is ^A At each occurrence independently O, S or NR ⁵⁵ ，Z ^A O, CO, S, NR at each occurrence ⁵⁵ Or C (R) ⁵⁴ ) ₂ ；R ⁵¹ 、R ⁵² 、R ⁵⁴ And R is ⁵⁵ Independently at each occurrence, H or a substituent; and R is ⁵³ Independently at each occurrence a substituent.

Optionally R ⁵¹ And R is ⁵² Independently at each occurrence selected from H; f, performing the process; c (C) _1-20 Alkyl groups in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ COO or CO, and one or more H atoms of the alkyl group may be replaced by F; an aromatic or heteroaromatic group Ar ³ Which is unsubstituted or substituted with one or more substituents.

In some embodiments, ar ³ May be an aromatic group such as phenyl.

Ar ³ One or more substituents, if present, may be selected from C _1-12 Alkyl groups in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ COO or CO, and one or more H atoms of the alkyl group may be replaced by F.

Preferably, each R ⁵⁴ Selected from the group consisting of:

H；

F；

straight, branched or cyclic C _1-20 Alkyl groups in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ Substitution of CO or COO, wherein R ⁷ Is C _1-12 Hydrocarbon group and the C _1-20 One or more H atoms of the alkyl group may be replaced by F; u- (Ar) of formula (Ak) ⁷ ) v, wherein Ak is C _1-20 Alkylene chains in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ Substitution of CO or COO; u is 0 or 1; ar (Ar) ⁷ An aromatic or heteroaromatic group independently at each occurrence that is unsubstituted or substituted with one or more substituents; and v is at least 1, optionally 1, 2 or 3.

Ar ⁷ Preferably selected from F, if present; cl; NO (NO) ₂ The method comprises the steps of carrying out a first treatment on the surface of the A CN; c _1-20 Alkyl groups in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ CO or COO, and one or more H atoms may be replaced by F. Preferably Ar ⁷ Is phenyl.

Preferably, each R ⁵¹ H.

Optionally R ⁵³ Independently at each occurrence selected from C _1-20 Alkyl groups in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ COO or CO, and one or more H atoms of the alkyl group may be replaced by F; and phenyl, which is unsubstituted or substituted with one or more substituents, optionally one or more C _1-12 Alkyl groups substituted in which one or more non-adjacent C atoms may be replaced by O, S, NR ⁷ COO or CO, and one or more H atoms of the alkyl group may be replaced by F.

Preferably, R as described anywhere herein ⁵⁵ Is H or C _1-30 A hydrocarbyl group.

Preferably D ¹ And D ² Each independently is a group of formula (VIIa). Exemplary groups of formula (VIIa) include, but are not limited to:

wherein Hc is independently at each occurrence C _1-20 Hydrocarbyl groups, e.g. C _1-20 Alkyl, unsubstituted aryl, or substituted by one or more C _1-12 An alkyl substituted aryl group. The aryl group is preferably phenyl.

In some embodiments, y ¹ And y ² Each 1.

In some embodiments, y ¹ And y ² At least one of which is greater than 1. In these embodiments, D ¹ And/or D ² The chains of the groups may each be linked in any direction. For example, at D ¹ Is a group of the formula (VIIa) and y ¹ In the case of 2, - [ D ¹ ]y ¹ -may be selected from any one of the following:

electron donor material

The bulk heterojunction layers described herein comprise an electron donating material and a compound of formula (I) or (X) as described herein.

Exemplary donor materials are disclosed, for example, in WO2013051676, the contents of which are incorporated herein by reference.

The electron donor material may be a non-polymeric material or a polymeric material.

In a preferred embodiment, the electron donating material is an organic conjugated polymer, which may be a homopolymer or copolymer, including alternating, random or block copolymers. The conjugated polymer is preferably a donor-acceptor polymer comprising alternating electron donating and electron accepting repeating units.

Conjugated organic polymers that are amorphous or semi-crystalline are preferred.

Further preferably, the electron donating polymer is a conjugated organic polymer having a low band gap typically between 2.5eV and 1.5eV, preferably between 2.3eV and 1.8 eV. Optionally, the electron donating polymer has a HOMO energy level no more than 5.5eV from the vacuum level. Optionally, the electron donating polymer has a HOMO energy level at least 4.1eV from the vacuum level. As exemplary electron donating polymers, polymers selected from conjugated hydrocarbon or heterocyclic polymers may be mentioned, including polyacenes, polyanilines, polyazules, polybenzofurans, polyfluorenes, polyfurans, polyindenofluorenes, polybenzdoles, polyphenylenes, polypyrazolines, polypyrenes, polypyridines, polytriarylamines, poly (phenylenevinylenes), poly (3-substituted thiophenes), poly (3, 4-disubstituted thiophenes), polyseleophenes, poly (3-substituted selenophenes), poly (3, 4-disubstituted selenophenes), poly (bithiophenes), poly (trithiophenes), poly (diselenophenes), poly (triseleophenes), polythiopheneo [2,3-b ] thiophene, polythiophene [3,2-b ] thiophene, polybenzothienes, polybenzo [1,2-b:4,5-b' j dithiophene, polyisothianthrene, poly (monosubstituted pyrrole), poly (3, 4-disubstituted pyrrole), poly-1, 3, 4-oxadiazole, polyisothiaindene, derivatives thereof and copolymers thereof.

Preferred examples of the donor polymer are copolymers of polyfluorene and polythiophene (each of which may be substituted), and polymers comprising benzothiadiazolyl and thienyl repeating units (each of which may be substituted).

Particularly preferred donor polymers comprise donor units (VIIa) provided as repeat units of the polymer, most preferably having electron-accepting repeat units, e.g. divalent electron-accepting units as described herein provided as polymeric repeat units.

Additional electron accepting material

In some embodiments, the compound of formula (I) or (X) as described herein is the only electron accepting material of the bulk heterojunction layer.

In some embodiments, the bulk heterojunction layer comprises a compound of formula (I) or (X) and one or more additional electron accepting materials. The one or more other electron accepting materials may be selected from non-fullerene acceptors and fullerenes.

Non-fullerene receptors are described, for example, in Cheng et al, "Next-generation organic photovoltaics based on non-fullerene acceptors", nature Photonics, vol.12, pages 131-142 (2018), the contents of which are incorporated herein by reference, and include, but are not limited to PDI, ITIC, ITIC, IEICO and derivatives thereof, for example fluorinated derivatives thereof, such as ITIC-4F and IEICO-4F.

Exemplary fullerene electron accepting compounds are C ₆₀ 、C ₇₀ 、C ₇₆ 、C ₇₈ And C ₈₄ Fullerenes or derivatives thereof, including but not limited to PCBM-type fullerene derivatives (including phenyl-C ₆₁ Methyl butyrate (C) ₆₀ PCBM)), TCBM-type fullerene derivatives (e.g., tolyl-C ₆₁ Methyl butyrate (C) ₆₀ TCBM)) and ThCBM type fullerene derivatives (e.g., thienyl-C ₆₁ Methyl butyrate (C) ₆₀ ThCBM))。

The fullerene derivative may have the formula (V):

wherein a forms, together with the C-C group of the fullerene, a monocyclic or fused ring group, which may be unsubstituted or substituted with one or more substituents.

Exemplary fullerene derivatives include formulas (Va), (Vb) and (Vc):

wherein R is ²⁰ To R ³² Each independently is H or a substituent.

Substituent R ²⁰ To R ³² Optionally and independently at each occurrence selected from the group consisting of: aryl or heteroaryl, optionally phenyl, which may be unsubstituted or substituted with one or more substituents; c _1-20 Alkyl groups in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ CO or COO, and one or more H atoms may be replaced by F.

The substituents of the aryl or heteroaryl groups, if present, are optionally selected from C _1-12 Alkyl groups in which one or more non-adjacent C atoms may be substituted by O, S, NR ⁷ CO or COO, and one or more H atoms may be replaced by F.

Formulations

The bulk heterojunction layer may be formed by any process including, but not limited to, thermal evaporation and solution deposition methods.

Preferably, the bulk heterojunction layer is formed by depositing a formulation comprising an electron donating material, an electron accepting material, and any other components of the bulk heterojunction layer dissolved or dispersed in a solvent or a mixture of two or more solvents. The formulation may be deposited by any coating or printing method including, but not limited to, spin coating, dip coating, roll coating, spray coating, doctor blade coating, wire bar coating, slot coating, ink jet printing, screen printing, gravure printing, and flexographic printing.

The one or more solvents of the formulation may optionally include a solvent selected from chlorine, C _1-10 Alkyl and C _1-10 Benzene substituted by one or more substituents of an alkoxy group or consisting thereof, wherein two or more substituents may be linked to form a ring, which may be unsubstituted or substituted by one or more C _1-6 Alkyl substituted, optionally toluene, xylene, trimethylbenzene, tetramethylbenzene, anisole, indane and alkyl substituted derivatives thereof, and tetrahydronaphthalene and alkyl substituted derivatives thereof.

The formulation may comprise a mixture of two or more solvents, preferably a mixture of at least one benzene substituted with one or more substituents as described above and one or more additional solvents. The one or more additional solvents may be selected from esters, optionally alkyl or aryl esters of alkyl or aryl carboxylic acids, optionally benzoic acid C _1-10 Alkyl esters, benzyl benzoate or dimethoxybenzene. In a preferred embodiment, a mixture of trimethylbenzene and benzyl benzoate is used as the solvent. In other preferred embodiments, a mixture of trimethylbenzene and dimethoxybenzene is used as the solvent.

The formulation may contain other components in addition to the electron accepting material, the electron donating material, and the one or more solvents. As examples of these components, binders, defoamers, deaerators, tackifiers, diluents, adjuvants, flow improvers, colorants, dyes or pigments, sensitizers, stabilizers, nanoparticles, surface-active compounds, lubricants, wetting agents, dispersants and inhibitors may be mentioned.

Organic electronic device

The polymers or compositions described herein may be provided as active layers of an organic electronic device. In a preferred embodiment, the bulk heterojunction layer of the organic light-responsive device, more preferably an organic photodetector, comprises a composition as described herein.

Fig. 1 illustrates an organic light responsive device according to some embodiments of the present disclosure. The organic light responsive device comprises a cathode 103, an anode 107 and a bulk heterojunction layer 105 disposed between the anode and the cathode. The organic light responsive device may be supported on a substrate 101, optionally a glass or plastic substrate.

Each of the anode and cathode may independently be a single conductive layer or may comprise multiple layers.

At least one of the anode and the cathode is transparent so that light incident on the device can reach the bulk heterojunction layer. In some embodiments, both the anode and the cathode are transparent. The transmittance of the transparent electrode may be selected according to the emission wavelength of a light source used with the organic photodetector.

Fig. 1 shows an arrangement in which a cathode is disposed between a substrate and an anode. In other embodiments, the anode may be disposed between the cathode and the substrate.

The organic light-responsive device may comprise layers other than the anode, cathode and bulk heterojunction layers shown in fig. 1. In some embodiments, a hole transport layer is disposed between the anode and the bulk heterojunction layer. In some embodiments, an electron transport layer is disposed between the cathode and the bulk heterojunction layer. In some embodiments, the work function modifying layer is disposed between the bulk heterojunction layer and the anode, and/or between the bulk heterojunction layer and the cathode.

The OPD area can be less than about 3cm ² Less than about 2cm ² Less than about 1cm ² Less than about 0.75cm ² Less than about 0.5cm ² Or less than about 0.25cm ² . Optionally, each OPD may be part of an array of OPDs, wherein each OPD is a single-phase optical fiber having an area as described herein, optionally less than 1mm ² Optionally at 0.5 microns ² To 900 micrometers ² Pixels of the array within the range of (a).

The substrate may be, but is not limited to, a glass or plastic substrate. The substrate may be an inorganic semiconductor. In some embodiments, the substrate may be silicon. For example, the substrate may be a silicon wafer. The substrate is transparent if in use incident light is to be transmitted through the substrate and the electrode supported by the substrate.

The bulk heterojunction layer comprises a polymer and an electron accepting compound as described herein. The bulk heterojunction layer may be comprised of these materials or may comprise one or more other materials, such as one or more other electron donating materials and/or one or more other electron accepting compounds.

Application of

The circuit may include an OPD connected to a voltage source for applying a reverse bias to the device and/or the device configured to measure photocurrent. The voltage applied to the photodetector may be variable. In some embodiments, the photodetectors may be continuously biased in use.

In some embodiments, the photodetector system comprises a plurality of photodetectors as described herein, such as image sensors of a camera.

In some embodiments, the sensor may comprise an OPD and a light source as described herein, wherein the OPD is configured to receive light emitted from the light source. In some embodiments, the light source has a peak wavelength of at least 900nm or at least 1000nm, optionally in the range of 1000 to 1500 nm.

The inventors have found that materials comprising an electron-accepting unit of formula (I) can be used to detect light of longer wavelengths, in particular 1300-1400 nm.

In some embodiments, the light from the light source may or may not change before reaching the OPD. For example, the light may be reflected, filtered, down-converted, or up-converted before it reaches the OPD.

The organic light responsive device described herein may be an organic photovoltaic device or an organic photodetector. The organic photodetectors described herein may be used in a wide variety of applications, including but not limited to detecting the presence and/or brightness of ambient light, as well as in sensors that include an organic photodetector and a light source. The photodetector may be configured such that light emitted from the light source is incident on the photodetector and changes in wavelength and/or brightness of the light may be detected, such as absorption, reflection, and/or emission of light due to an object (e.g., a target material in a sample disposed in an optical path between the light source and the organic photodetector). The sample may be a non-biological sample, such as a water sample, or a biological sample taken from a human or animal subject. The sensor may be, but is not limited to, a gas sensor, a biosensor, an X-ray imaging device, an image sensor such as a camera image sensor, a motion sensor (e.g., for security applications), a proximity sensor, or a fingerprint sensor. The 1D or 2D photosensor array may comprise a plurality of photodetectors as described in the image sensor. The photodetector may be configured to detect light emitted from a target analyte that emits light when illuminated by the light source, or the target analyte is bound to a luminescent tag that emits light when illuminated by the light source. The photodetector may be configured to detect the wavelength of light emitted by the target analyte or luminescent tag bound thereto.

Examples

Example 1 of Compounds

Compound example 1 was prepared according to the following reaction scheme:

synthesis of Compound 1

Toluene (60 ml) was added to CPDT-SnBu under nitrogen ₃ (4.84 g,7.00 mmol) and BisBT-diBr (1.15 g,3.26 mmol). The mixture was degassed for 15 min and tris (2-methylphenyl) phosphine (0.30 g,0.98 mmol) and tris (dibenzylideneacetone) dipalladium (0.24 g,0.26 mmol) were added, and the mixture was degassed for an additional 5 min. The mixture was heated at 70 ℃ for 30 minutes and then at 100 ℃ overnight. After completion, the solvent was removed on a rotary evaporator and purified by column chromatography (silica gel; heptane/toluene) to give compound 1 (2.37 g) as a dark brown oil.

Synthesis of Compound 2

A solution of Compound 1 (0.5 g,0.50 mmol) in THF (5 ml) was cooled to-40℃and N-bromosuccinimide (0.18 g,1 mmol) was added in portions. The mixture was stirred at this temperature for 4.5 hours and quenched with 10% sodium thiosulfate solution, extracted with heptane, dried over magnesium sulfate and evaporated to give compound 2 as a black oil.

Synthesis of Compound 3

Compound 2 (0.53 g,0.46 mmol) and thiophene-SnBu ₃ (1.03 g,1.67 mmol) in toluene (9 ml) was degassed for 15 minutes. Tris (2-methylphenyl) phosphine (0.04 g,0.14 mmol) and tris (dibenzylideneacetone) dipalladium (0.03 g,0.04 mmol) were added and the mixture was degassed for an additional 5 minutes. The mixture was heated at 70 ℃ for 30 minutes and then at 100 ℃ overnight. After completion, it was diluted with toluene and extracted with water. The organic phase was placed in a flask, trifluoroacetic acid (4 ml) was added and stirred at room temperature for 30 minutes, then at 40 ℃ for an additional 30 minutes. The reaction mixture was cooled to room temperature, water (10 ml) was added, then saturated sodium bicarbonate solution was added, transferred to a separatory funnel and further extracted with this solution. The organic phase was dried over magnesium sulfate, filtered and concentrated in vacuo to give a violet oil. Purification by column chromatography (silica; heptane/toluene) afforded compound 3 (0.25 g) as a violet solid.

Synthesis of Compound 4

Compound 3 (0.25 g,0.17 mmol), IC2CN (0.21 g,0.83 mmol) and p-toluene sulfonic acid (0.24 g,1.24 mmol) were placed in a flask, toluene (6 ml) and ethanol (8 ml) were added, and the mixture was degassed with nitrogen for 15 min and heated overnight at 70 ℃. Thereafter, the mixture was filtered and the resulting solid was washed with hot ethanol, methanol and pentane. Purification by column chromatography (silica; toluene DCM and THF) gave compound example 1 (0.07 g).

¹ H NMR(300MHz,THF-d ₈ )：δ9.28(s,2H),8.98(s,2H),8.79(s,2H),8.35(s,2H),7.97(t,2H),7.83(s,2H),4.35(d,4.7Hz,4H),2.22(m,8H),1.96(m,2H),1.49-1.44(m,9H),1.12-0.93(m,54H),0.75-0.60(m,27H)。

LCMS(APCI+ve)：1924.91([M+H]+)。

Band gap and absorption spectrum

Fig. 2 shows the absorption spectra of the unbridged comparative compounds shown in compound example 1 and table 1 in o-dichlorobenzene solution.

Referring to table 1, compound example 2 has a smaller HOMO-LUMO bandgap as measured by square wave voltammetry as compared to the comparative compound.

TABLE 1

Device example 1

A device having the following structure was prepared:

cathode/donor: acceptor layer/anode

Glass substrates coated with an Indium Tin Oxide (ITO) layer were treated with Polyethylenimine (PEIE) to alter the work function of the ITO.

The donor was applied by bar coating from a 15mg/ml solution in o-dichlorobenzene: a mixture of donor polymer and compound example 1 (acceptor) in a mass ratio of acceptor of 1:0.8 was deposited on the modified ITO layer. The thin film was dried at 80 ℃ to form a bulk heterojunction layer about 500nm thick.

By thermal evaporation (MoO) ₃ ) And sputtering (ITO) to form MoO on the bulk heterojunction ₃ (10 nm) and ITO (50 nm).

The donor polymer shown below has donor repeating units and acceptor repeating units of formula (VIIa). The donor polymer may be prepared as described in WO2013/051676, the contents of which are incorporated herein by reference.

Comparison device 1

For comparison purposes, comparative device 1 was prepared as described for device example 1, except that comparative compound 1 was used instead of compound example 1, and the donor polymer/comparative compound 1 mixture was from 1,2, 4-trimethylbenzene: methyl benzoate 50:50v/v solvent mixture deposition:

comparative Compound 1

Referring to fig. 3, the external quantum efficiency of device example 1 was higher than that of the comparative device around 1400-1700 nm.

The dark current densities of device example 1 and comparative device 1 are shown in fig. 4.

Modeling instance

All modeling described in these examples was performed using Gaussian09 software, available from Gaussian (Gaussian), using Gaussian09 and B3LYP (functional).

The HOMO and LUMO energy levels are modeled for each donor and acceptor unit. The results are shown in tables 2 to 4

TABLE 2

TABLE 3 Table 3

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TABLE 4 Table 4

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Acceptor unit A ¹ Preferably has a modeled LUMO at least 2.9eV or at least 3.0eV from the vacuum level.

For the point of A ² And D ¹ (z ¹ Between =0) or at a ³ And D ² (z ² =0) without a bridge between them, the HOMO and LUMO energy levels were modeled.

The results are shown in Table 5. S1f corresponds to the oscillator intensity (predicted absorption intensity) that transitions from S1, epopt being the modeled optical energy gap.

As shown above, compound example 1 has a smaller band gap as measured by square wave voltammetry than comparative compound 1. As shown in the first two entries of table 5, this smaller band gap was also observed in the modeling energy levels for the corresponding model compounds, which differed from compound example 1 and comparative compound 1 only in that for computational simplicity, the alkyl group was methyl. This indicates the accuracy of the model.

TABLE 5

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The effect of the different bridging groups is shown in table 6.

TABLE 6

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Table 7 compares compounds having a bridge between acceptor groups and a donor group with compounds having two donor groups between acceptor groups. Although the band gaps are similar, the HOMO of the compound containing both donor groups is quite shallow, which is expected to result in lower compound stability.

TABLE 7

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Claims

1. A compound of formula (I):

wherein:

A ¹ is a divalent heteroaromatic electron accepting group;

A ² and A ³ Each independently is a monovalent electron accepting group;

D ¹ and D ² Independently at each occurrence an electron donating group;

B ¹ and B ² Independently at each occurrence a bridging group;

x ¹ and x ² Each independently 0, 1, 2 or 3;

y ¹ and y ² Each independently is at least 1; and is also provided with

z ¹ And z ² Each independently 0, 1, 2 or 3,

provided that z is ¹ And z ² At least one of which is at least 1.

2. A compound of formula (I):

wherein:

A ² and A ³ Each independently is a monovalent electron accepting group;

D ¹ and D ² Independently at each occurrence an electron donating group;

B ¹ and B ² Independently at each occurrence a bridging group;

x ¹ and x ² Each independently 0, 1, 2 or 3;

y ¹ and y ² Each independently is at least 1; and is also provided with

z ¹ And z ² Each independently 0, 1, 2 or 3,

3. The compound according to claim 1 or 2, wherein a ¹ Is a group of formula (II):

wherein:

4. A compound according to claim 3, wherein a ¹ Is a group of formula (IIa):

5. a compound according to claim 3, wherein the group of formula (II) has formula (IIb):

6. the compound of claim 5, wherein two R ¹ The groups are not linked.

7. The compound of claim 6, wherein each R ¹ Independently selected from H; f, performing the process; a CN; NO (NO) ₂ ；C _1-20 Alkyl groups in which one or more non-adjacent C atoms may be represented by O, S, CO, COO, NR ⁴ 、PR ⁴ Or Si (R) ³ ) ₂ Replacement, and one or more H atoms may be replaced by F; and aryl or heteroaryl, which may be unsubstituted or substituted with one or more substituents, wherein R ³ And R is ⁴ Each independently is H or a substituent.

8. The compound of claim 5, wherein two R ¹ The groups are linked.

9. The compound of claim 8, wherein the compound of formula (IIb) has formula (IIb-1) or (IIb-2):

wherein the method comprises the steps of

Ar ² An aromatic or heteroaromatic group that is unsubstituted or substituted with one or more substituents; and is also provided with

X is selected from O, S, SO ₂ 、NR ⁴ 、PR ⁴ 、C(R ³ ) ₂ 、Si(R ³ ) ₂ C= O, C =s and c=c (R ⁵ ) ₂ Wherein

R ³ And R is ⁴ Independently at each occurrence, is selected from H and substituents, and R ⁵ Independently at each occurrence an electron withdrawing group.

10. The compound according to claim 9, wherein Ar ² Is benzene unsubstituted or substituted with one or more substituents.

11. The compound of any one of the preceding claims, wherein x ¹ And x ² At least one of which is at least 1, and B ¹ Independently at each occurrence selected from the group consisting of vinylidene, arylene, heteroarylene, arylene vinylene, and heteroarylvinylene, each of which is unsubstituted or substituted with one or more substituents.

12. The compound of any one of the preceding claims, wherein z ¹ And z ² At least one of which is at least 1, and B ² Independently at each occurrence selected from the group consisting of vinylidene, arylene, heteroarylene, arylene vinylene, and heteroarylvinylene, each of which is unsubstituted or substituted with one or more substituents.

13. The compound of any one of the preceding claims, wherein D ¹ And D ² Each of which is a single pieceUnits independently selected from formulas (VIIa) through (VIIp):

wherein Y is ^A At each occurrence independently O, S or NR ⁵⁵ ，Z ^A O, S, NR at each occurrence ⁵⁵ Or C (R) ⁵⁴ ) ₂ ；R ⁵¹ 、R ⁵² 、R ⁵⁴ And R is ⁵⁵ Independently at each occurrence, H or a substituent; and R is ⁵³ Independently at each occurrence a substituent.

14. The compound of any one of the preceding claims, wherein a ² And A ³ Comprises a non-aromatic carbon-carbon double bond, and a carbon atom of the carbon-carbon double bond is directly bonded to D ¹ Or D ² Or if present, to B ² 。

15. The compound of any one of the preceding claims, wherein a ² And A ³ Each independently selected from the group of formulae (IIIa) to (IIIq)

Wherein:

u is a 5-or 6-membered ring, which is unsubstituted or substituted with one or more substituents and which may be fused to one or more additional rings;

R ¹⁰ is H or a substituent;

j is O or S;

R ¹³ each occurrence of which is a substituent;

R ¹⁵ independently at each occurrence H or a substituent

R ¹⁶ Is a substituent;

Ar ⁶ is a 5 membered heteroaromatic group which is unsubstituted or substituted with one or more substituents;

T ¹ 、T ² and T ³ Each independently represents an aryl or heteroaryl ring which may be fused to one or more additional rings, and T ¹ 、T ² And T ³ Independently unsubstituted or substituted with one or more substituents; and is also provided with

Ar ⁸ Is a fused heteroaromatic group which is unsubstituted or substituted with one or more substituents and which is bonded to B ² And is bonded to B ² Boron substituents of (a).

16. The compound of claim 15, wherein a ² And A ³ At least one of which is a group of formula (IIIa-1):

wherein:

each X is ¹ To X ⁴ Independently CR ¹² Or N, wherein R ¹² At each occurrence H or selected from C _1-20 Substituents for hydrocarbyl and electron withdrawing groups.

17. The compound of any one of the preceding claims, wherein the polymer has an absorbance peak greater than 900 nm.

18. A composition comprising an electron donating material and an electron accepting material, wherein the electron accepting material is a compound according to any of the preceding claims.

19. An organic electronic device comprising an active layer comprising a compound or composition according to any one of the preceding claims.

20. The organic electronic device of claim 19, wherein the organic electronic device is an organic light-responsive device comprising a bulk heterojunction layer disposed between an anode and a cathode, and wherein the bulk heterojunction layer comprises the composition of claim 18.

21. The organic electronic device of claim 20, wherein the organic light responsive device is an organic photodetector.

22. A photosensor comprising a light source and the organic photodetector of claim 21, wherein the photosensor is configured to detect light emitted from the light source.

23. The photosensor of claim 22, wherein the light source emits light having a peak wavelength greater than 900 nm.

24. A formulation comprising a compound or composition according to any one of claims 1 to 18 dissolved or dispersed in one or more solvents.

25. A method of forming an organic electronic device according to any one of claims 19 to 21, wherein the forming of the active layer comprises depositing the formulation of claim 24 onto a surface and evaporating the one or more solvents.