WO2013096915A1 - Stannyl derivatives of naphthalene diimides and related compositions and methods - Google Patents

Abstract

Naphthalene diimide (NDI) compounds comprising core substituent X groups, wherein X is an electron poor, optionally substituted, aryl or heteroaryl group. Compounds can be prepared with use of NDI-tin precursor compounds. Compounds are used in organic electronic devices including organic field effect transistors.

Description

Stannyl Derivatives Of Naphthalene Diimides And Related

Compositions And Methods

RELATED APPLICATIONS

This application claims priority to US provisional application serial no. 61/579,608 tiled December 22, 201 1 and European application serial no.

12189295.4 tiled October 19, 2012, the complete disclosures of which are hereby incorporated by reference in their entirety.

BACKGROUND

Organic electronics is an important area for commercial development including, for example, advanced transistors, displays, lighting, photovoltaic, and sensing devices. The broad diversity of organic compounds and materials provides advantages for organic electronics.

In but one example of the versatile chemistry and material science available for organic electronics, tetracarboxylic diimide derivatives of rylenes, particularly of napthalene and perylene (NDIs amd PDIs, respectively), represent one of the most extensively studied classes of functional materials in the field of organic electronics. The thermal, chemical, and photochemical stability as well as their high electron affinities and charge-carrier mobilities render these materials attractive for applications in organic field-effect transistors (OFETs) and organic photovoltaic cells (OPVs). They have also been widely used as acceptors in transient absorption studies of photoinduced electron-transfer, again due to their redox potentials, and to the stability and distinctive absorption spectra of the corresponding radical anions.

The N,N -substituents of PDIs and NDIs generally only have minimal influence on the optical and electronic properties of isolated molecules, although they can be used to control solubility, aggregation, and intermolecular packing in the solid-state. In contrast, core substitution of these species typically has a much more significant effect on the redox potentials (enabling, in some cases, the electron affinities to be brought within a range in which air-stable OFET operation can be achieved) and optical spectra of these species. Moreover, core substitution can be used as a means of constructing more elaborate architectures such as conjugated polymers and donor or acceptor functionalized products.

Both mono- and di-metallated NDI species are valuable building blocks for new types of conjugated NDI derivatives in which acceptor groups are directly conjugated to the NDI core. Air-stable device operation in NDIs is generally achieved through two methods: 1) incorporation of kinetic barriers and/or 2) increasing the magnitude of the electron affinity (EA). In NDI chemistry, kinetic barriers have been achieved using fluoroalkyl substitution, which, through dense packing of the chains in the thin film, is believed to act as a barrier against ambient species penetration. However, performance in devices fabricated with materials of this type has been shown to degrade over time.. On the other hand, an increase in the electron affinity, which is generally achieved through functionalization with electron-withdrawing substituents, can lead to materials with a thermodynamic stability towards oxidation in air that does not rely on the packing of the material in the film. Materials exhibiting intrinsically air-stable electron transport, i.e.; in which electron transport is not affected by environmental conditions and / or molecular arrangement in the film, are desirable.

SUMMARY

Embodiments described herein include compositions and compounds, as well as methods of making, methods of using, and inks, and devices comprising these compositions and compounds.

For example, one embodiment provides a compound represented by:

or

or

wherein each R independently is a C 1-C30 normal, branched, or cyclic alkyl, aryl, heteroaryl, alkyl-aryl, or alkyl-heteroaryl group optionally substituted with one or more halide, cyano, alkyl, or alkoxy groups; and Rj , R₂, and R₃ are independently hydrogen or an organic radical; and n is 2 to 100, and X is an electron poor aryl or heteroaryl group. In one embodiment, the compound is a polymer having a number average molecular weight of at least 5,000 Da, or at least 10,000 Da, or at least 20,000 Da, or at least 25,000 Da,

In another embodiment, the compound is represented by:

In another embodiment, the compound is represented by:

In another embodiment, the compound is represented by:

In other embodiments, the electron poor aryl or heteroaryl group, X, is

wherein R and R independently are any halogen, pseudohalogen, or optionally substituted C₁ -C30 organic radical.

In other embodiments, the electron poor aryl or heteroaryl roup, X, is

In other embodiments, the group X is

In other embodiments, the group X is

wherein R is nitrile.

In other embodiments, each R independently is a C₁-C30 normal, branched or cyclic alkyl group, and R_{l s} R₂, and R₃ are hydrogen.

In other embodiments, the compound is represented by:

Other embodiments including a method comprising: reacting at least one first naphthalene diimide (NDI) compound comprising at least one stannyl substituent bonded to the naphthalene moiety of the NDI compound in a coupling reaction to form at least one bond between the NDI compound and an electron poor aryl or heteroaryl compound that is not an NDI compound. Other embodiments include wherein the reaction produces a compound as described hereinabove.

Other embodiments provide for a composition comprising at least one compound as described herein or a compound prepared by the methods described herein.

Other embodiments provide for an ink composition comprising at least one solvent and at least one compound as described herein or a compound made by a method described herein.

Other embodiments include a device comprising or uses of at least one compound as described herein or a compound prepared by a method as described herein, or a composition as described herein or with use of an ink composition as described herein, wherein the device is, for example, an organic light emitting dioded (OLED), an organic photovoltaic device (OPV), an organic field effect transistor (OFET), or sensing device.

In one embodiment, the NDI, which is itself electron deficient, and a second electron deficient monomer are copolymerized. Other embodiments include copolymers comprising a first electron deficient subunit comprising NDI and a second electron deficient subunit comprising an aromatic heterocycle. In one embodiment, the heteroaromatic heterocycle comprises a tetrazine. In another embodiment, the aromatic heterocycle comprises a thiazolothiazole. The aromatic heterocycle may be further substituted with solublizing groups, compatiblizing groups, electron withdrawing groups, or electron donor groups. The copolymers are very electron deficient by virtue of having two electron deficient subunits.

At least one advantage for at least one embodiment is that the important

Stille coupling reaction can be used more expansively for the NDI system to expand the variety of organic compounds and materials that can be made. This allows one to "tune" properties such as the ionization potential, oxidation potential, electron affinity, reduction potential, optical absorption, and fluorescence of the compound or material for a particular application so it can function well with other components.

At least one additional advantage for at least one embodiment is that compounds and materials can be made having useful or improved properties. For example, in one embodiment, good electron mobility values can be achieved. Also, LUMO levels of the compounds can be achieved at lower than the LUMO level of pure NDI. In another embodiment, useful field-effect transistors can be prepared. In one embodiment, air, water, and thermally stable compounds can be made. Compounds with good solubility can be made.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1 a discloses normalized absorption of QS-1 -17c in a film and in solution; Figure l b shows a cyclic voltammogram o QS-1 -17c; Figure l c shows thermal properties of QS-1 -17c by thermogravimetric analysis (TGA) under nitrogen; Figures Id and l e show the transfer and output characteristics of a particular top- gate bottom-contact OFET of QS-I- 1 7c (Device SS- 1 -81 ) respectively, with Au source/drain electrodes W/L= 2550 μηι/ 180 μηι ).

Figure 2a discloses normalized absorption of QS-l-55a in a film and in solution; Figure 2b shows a cyclic voltammogram of QS-1 -55a; Figure 2c shows thermal properties of QS-1 -55a by thermogravimetric analysis (TGA) under nitrogen; Figures 2d and 2e show the transfer and output characteristics of a particular top- gate bottom-contact OFET of QS- 1 -55a (Device SS- 1 -80) respectively, with Au source/drain electrodes ( W/L= 2550 μιη/180 μηι).

Figure 3a discloses normalized absorption of QS-2-5a-C in a film and in solution; Figure 3b shows a cyclic voltammogram of QS-2-5a-C; Figure 3c discloses normalized absorption of QS-2-5a-DCBin a film and in solution;

Figure 3d shows a cyclic voltammogram of QS-2-5a-DCB.

Figure 4a discloses normalized absorption of QS-2-5d in a film and in solution; Figure 4b shows a cyclic voltammogram of QS-2-5d.

DETAILED DESCRIPTION

Introduction

All references cited herein are incorporated by reference in their entirety. U.S. provisional applications 61/475,888 filed April 15, 201 1 to Polander et al.; 61/579,608 filed December 22, 201 1 to Polander et al.; 61/591 ,767 filed January 27, 2012 to Polander et al. are hereby incorporated by reference in their entirety including NDI-Sn compounds and methods of making NDI-Sn compounds. Also incorporated are the aryl and heteroaryl structures and working examples, including Figures.

The PhD thesis by Lauren Polander, 201 1, "Organic Charge-Transport Materials Based on Oligothiophene and Napthalene Diimide: Towards Ambipolar and n-Channel Organic Field-Effect Transistors," provides additional information about the presently claimed inventions.

Important synthetic methods which can be used as appropriate herein to prepare compounds are generally described in March 's Advanced Organic Chemistry, 6^th Ed., 2007.

As used herein, "halo" or "halogen" or even "halide" can refer to fluoro, chloro, bromo, and iodo.

As used herein, "alkyl" can refer to a straight-chain, branched, or cyclic saturated hydrocarbon group. Examples of alkyl groups include methyl (Me), ethyl (Et), propyl (e.g., n- propyl and iso-propyl), butyl (e.g., n-butyl, iso-butyl, sec-butyl, tert-butyl), pentyl groups (e.g., n-pentyl, iso- pentyl, neopentyl), and the like. In various embodiments, an alkyl group can have 1 to 30 carbon atoms, for example, 1-20 carbon atoms (i.e., C|-C₂o alkyl group). In some embodiments, an alkyl group can have 1 to 6 carbon atoms, and can be referred to as a "lower alkyl group." Examples of lower alkyl groups include methyl, ethyl, propyl (e.g., n-propyl and iso-propyl), and butyl groups (e.g., n-butyl, iso-butyl, sec-butyl, tert-butyl).

As used herein, "haloalkyl" can refer to an alkyl group having one or more halogen substituents. At various embodiments, a haloalkyl group can have 1 to 20 carbon atoms, for example, 1 to 10 carbon atoms (i.e., Q-Cio haloalkyl group). Examples of haloalkyl groups include CF₃, C2F5, CHF₂, CH₂F, CC1₃, CHCb, CH₂C1, C2CI5, and the like. Perhaloalkyl groups, i.e., alkyl groups where all of the hydrogen atoms are replaced with halogen atoms (e.g., perfluoroalkyl groups such as CF₃ and C2F₅), are included within the definition of "haloalkyl." As used herein, "alkoxy" can refer to -O-alkyl group. Examples of alkoxy groups include, but are not limited to, methoxy, ethoxy, propoxy (e.g., n-propoxy and isopropoxy), t- butoxy groups, and the like. The alkyl group in the -O-alkyl group can be substituted with 1 -5 R¹ groups and R¹ is as defined herein.

As used herein, "heteroatom" can refer to an atom of any element other than carbon or hydrogen and includes, for example, nitrogen, oxygen, silicon, sulfur, phosphorus, and selenium.

As used herein, "heteroaryl" can refer to an aromatic monocyclic ring system containing at least one ring heteroatom selected from oxygen (O), nitrogen (N), sulfur (S), silicon (Si), and selenium (Se), or a polycyclic ring system wherein at least one of the rings present in the ring system is aromatic and contains at least one ring heteroatom. A heteroaryl group, as a whole, can have, for example, from 5 to 16 ring atoms and contain 1 -5 ring heteroatoms (i.e., 5-16 membered heteroaryl group). In some embodiments, heteroaryl groups can be substituted with one or more terminal R¹ groups, where R¹ is as defined herein. Both substituted and unsubstituted heteroaryl groups described herein can comprise between 1-30, or 1-20 carbon atoms, including the R¹ substituents.

As used herein, "aryl" can refer to a broad variety of unsaturated cyclic groups which can provide conjugation and delocali/ation and can be fused and can be optionally substituted, as known in the art. Aryl groups with C₆ to C₄0 or C(, to C₃0 in carbon number can be used, for example.

As described more herein, substituents can be, for example, halo, alkyl, haloalkyl, alkoxy, heteroaryl, and aryl.

Preparation Of Ndi-Sn Precursor Compounds

NDI oligomers and polymers useful in the presently embodied methods can be prepared from the NDI-tin compounds. These methods can be used to access a wide range of NDI compounds along with higher rylene compounds such as PDI and related perylene compounds. However, NDI compounds are the preferred moiety of the most embodiments.

One embodiment provides, for example, a composition comprising at least one naphthalene diimide (NDI) compound comprising at least one stannyl substituent bonded to the naphthalene moiety of the NDI compound.

"Naphthalene diimide" or "naphthalene tetracarboxylic diimide" (NDI) compounds, derivatives, and materials are known in the art. See, for example, US Patent Publications 201 1/0269967; 201 1/0269966; 2011/0269265;

201 1/0266529; 201 1/0266523; 2011/0183462; 2011/0180784; 2011/0120558; 201 1/0079773; 2010/0326527; and 2008/0021220. Other examples can be found in, for example, Hu et al., Chem. Mater., 201 1, 23, 1204-1215 ("core-expanded naphthalene diimides"); Wei et. al, Macromol. Chem. Phys., 2009, 210, 769-775 ("naphthalene bisimides" or NBI); Jones et al., Chem. Mater., 2007, 19, 1 1, 2703-2705; and Durban et al, Macromolecules, 2010, 43, 6348-6352; Guo et al., Organic Letters, 2008, 10, 23, 5333-5336 ("naphthalene bisimides"); Roger et al., J. Org. Chem., 2007, 72, 8070-8075; Thalaker et al., J. Org. Chem., 2006, 71, 8098-8105; Oh et al., Adv. Fund. Mater., 2010, 20, 2148-2156; Suraru et al., Synthesis, 2009, 1 1 , 1841-1845; Polander et al., Chem. Mater., 201 1 , 23, 3408- 3410; Yan et al, Nature, February 5, 2009, 457, 679-686; Chopin et al., J.

Mater. Chem., 2007, 4139-4146; Bhosale et al., New J. Chem., 2009, 33, 2409- 2413; and Chen et al., J. Am. Chem. Soc, 2009, 131, 8-9. In the present application, "NDI" and "NBI" are deemed equivalent. The core NDI structure can be called l ,4:5,8-napthalenetetracarboxylic acid diimide.

One representation of an NDI structure is as follows, showing the core naphthalene group and the two imide groups:

(NDI)

Herein, at least one of the substituents Ri, R₂, R₃, and/or R₄ can be functionalized to be a tin (or stannyl) group wherein the tin atom is directly covalently bonded to the naphthalene core. The identity of the two groups, R₅ and R₆ bonded to the imide, independently of each other are not particularly limited to the extent that the compounds can be synthesized. In one

embodiment, the R₅ and R₆ groups are the same groups. The R₅ and R₆ bonded to the imide can be a broad range of organic groups. One example of the R₅ and R group alkyl, including n-alkyl or branched alkyl, including for example, hexyl. Cyclic alkyl structures can be also used. The R₅ and R₆ groups can be optionally subsituted with groups such as, for example, halide, cyano, alkyl, and/or alkoxy.

NDI compounds can be prepared from precursor compounds including, for example, naphthalene anhydride (NDA).

The naphthalene moiety in the NDI can be substituted on one or both of the carbocyclic aromatic rings comprising the naphthalene moiety. Four substitution sites are possible at the 2, 3, 6, and 7 positions of the NDI so there can be one, two, three, or four substituents. In addition, the one or both nitrogens of the imide groups in NDI can be also substituted. Substitution can promote solubility.

The naphthalene moiety in the NDI can be substituted on one or both of the carbocyclic aromatic rings comprising the naphthalene moiety with at least one stannyl substituent. The stannyl substituent can be represented by -SnR'₃. For example, the compound can have one stannyl substituent, or it can have two stannyl substituents. In many of the embodiments herein, the NDI is substituted on one or both of the earbocyelie aromatic rings comprising the naphthalene moiety with at least two stannyl substituents.

The stannylated NDI compounds useful for synthesis of the embodiments herein include, but are not limited to the following embodiments:

One embodiment provides a composition comprising at least one naphthalene diimide (NDI) compound comprising at least one stannyl substitucnt bonded to the naphthalene moiety of the NDI compound.

In one embodiment, the compound has one stannyl substitucnt. In another embodiment, the compound has two stannyl substituents.

In one embodiment, the stannyl substitucnt is -SnR'3 wherein the IV groups, independently, are alkyl or aryl.

In one embodiment, the NDI compound comprises at least one NDI moiety. In another embodiment, the NDI compound comprises at least two NDI moieties.

In one embodiment, the molecular weight of the compound is about 2,000 g mol or less. In another embodiment, the molecular weight of the compound is about 1 ,000 g/mol or less. In another embodiment, the molecular weight of the compound is about 750 g/mol or less.

In one embodiment, the compound is, or the compounds are, represented by:

wherein X is H or a stannyl substituent; wherein each R is independently a C1-C30 normal, branched, or cyclic alkyl, aryl, heteroaryl, alkyl-aryl, or alkyl- heteroaryl group optionally substituted with one or more halide, cyano, alkyl, or alkoxy groups; and wherein each of the R' moieties is independently an alkyl or aryl moiety. In one embodiment, each R is independently an optionally substituted C1 -C30 alkyl moiety and each of the R' moieties is independently a C1 -C20 alkyl moiety. embodiment, the compound is represented

wherein each R is independently a C1-C30 normal, branched, or cyclic alkyl, aryl, heteroaryl, alkyl-aryl, or alkyl-heteroaryl group optionally substituted with one or more halide, cyano, alkyl, or alkoxy groups; and wherein each of the R' moieties is independently an alkyl or aryl moiety. In one embodiment, each R is independently an optionally substituted C1-C30 alkyl moiety and each of the R' moieties is independently a C1 -C20 alkyl moiety.

In one embodiment, the compound is represented by:

wherein each R is independently a C1 -C30 normal, branched, or cyclic alkyl, aryl, heteroaryl, alkyl-aryl, or alkyl-heteroaryl group optionally substituted with one or more halide, cyano, alkyl, or alkoxy groups; and wherein each of the R' moieties is independently an alkyl or aryl moiety. In one embodiment, each R is independently an optionally substituted C1-C30 alkyl moiety and each of the R' moieties is independently a C1-C20 alkyl moiety.

Another embodiment provides for naphthalene diimide organotin compounds having the structure (IV);

wherein: R ¹ and R¹ are independently selected from a C₁-C30 normal, branched, or cyclic alkyl, aryl, heteroaryl, alkyl-aryl, or alkyl-heteroaryl group optionally substituted with one or more halide, cyano, alkyl, or alkoxy groups; R\ R \ and R⁴ are independently selected from hydrogen, halide, or a C1-C30 organic group independently selected from cyano, normal, branched, or cyclic alkyl, perlluoroalkyl, aryl, heteroaryl, alkyl-aryl, and alkyl-heteroaryl groups, optionally substituted with one or more fluoro, cyano, alkyl, alkoxy groups; and R⁹ is an alkyl or aryl group.

In one embodiment, R¹ is a C₁ -C30 normal or branched alkyl or fluoroalkyl group. In another embodiment, R , R , and R are independently selected from hydrogen, fluoro and cyano. In another embodiment, R⁹ is a CYC₁₂ alkyl group. NDI Compounds Comprising Electron Poor Aryl/Heteroaryl Moieties

The tin-NDI compounds can be reacted with electrophilic compounds such as arylhalides or heteroarylhalides to form aryl or heteroaryl derivatives of the

NDI. The following are some representations of compounds and materials including compounds which can be represented as (Ar)_n- DI-(Ar')_n:

The X groups can be electron deficient or electron-poor aryl or heteroaryl moieties. Electron-rich versus electron-deficient heteroaryl moieties are known in the art. See, for example, PCT publication WO 2011/098495 (Georgia Tech). The electron-poor substituents can be bonded to the NDI moiety via reaction of the tin substituent(s).

In other embodiments, a relatively electron poor heteroaryl radical can be used, such as for example one of the formulas shown below:

In connection with substituents for the aryl or heteroaryl groups described above, R¹³ and R¹⁴ can be any C 1-C30 organic radical. Examples include but are not limited to a Ci-C_l8 alkyl, perfluoroalkyl, or alkoxy group, and R¹³ can be hydrogen, halide, any C1-C30 organic radical, such as but not limited to a CpCis alkyl, perfluoroalkyl, or alkoxy group , including Si(R²)₃, Si(OR²)₃, -B(-OR²¹)₂, or Sn(R²)₃.

In many embodiments, the radicals are "terminal" aryl or heteroaryl radicals, such as the electron poor radicals shown below:

In another embodiment, oligomers and polymers are prepared wherein electron deficient aryl compounds are used as comonomers.

In addition, U.S. Provisional Application 61/475,888 filed April 15, 2011 described compounds which can be represented by:

wherein R₂, R₃, and R4 independently can be, and X can be, for example, as described in U.S. Provisional Application 61/475,888 filed April 15, 201 1, including fused ring and heteroaryl groups. Electron poor or electron deficient bivalent X groups can be used herein as well.

Additional embodiments of aryl and heteroaryl (hAr) compounds represented by "X" in the embodiments herein include those in in U.S.

Provisional Application 61/475,888 filed April 15, 201 1 , as follows:

or

wherein "a" is an integer 1, 2, 3, or 4; each X and X' is independently

6 * 6

selected from O, S, Se, or NR , wherein R is a C1-C30 organic group, such as for example an independently selected normal, branched, or cyclic alkyl, fluoroalkyl, aryl, heteroaryl, alkyl-aryl, and alkyl-heteroaryl groups, which can be optionally substituted with one or more fluoro, cyano, alkyl, alkoxy groups; each Y, Y', Y" and Y'" is independently selected from N, and CR⁷, where R⁷ is hydrogen, fluoro, or a C1 -C30 organic group, such as for example an

independently selected cyano, normal, branched, or cyclic alkyl, perfluoroalkyl, alkoxy, perfluoro alkoxy, aryl, heteroaryl, alkyl-aryl, and alkyl-heteroaryl groups, which can be optionally substituted with one or more fluoride, cyano, alkyl, alkoxy groups; each Z and Z' is independently selected from O, S, Se, C(R )₂, Si(R⁸)₂, NR⁸, (CO), (CO)₂ or C=C(CN)₂, wherein R⁸ is a C1-C30 organic group, for example independently selected from normal, branched, or cyclic alkyl, perfluoroalkyl, aryl, heteroaryl, alkyl-aryl, and alkyl-heteroaryl groups, optionally substituted with one or more fluoro, cyano, alkyl, alkoxy groups.

In many related embodiments of the generic bivalent hAr heteroaryls shown above, X and X' can be S, and/or Y, Y', Y" and Y' ' ' can be N or CH, and/or Y' ' and Y" ', can be CR⁷, and/or Z and Z' can be S or NR⁸, and/or Z and Z' can be (CO), i.e. a carbonyl group, and/or Z and Z' can be (CO)₂., i.e. an a- biscarbonyl group, and/or Z and Z' can be C=C(CN)₂, ie. a substituted malanonitrile group, and/or Z and Z' can be C(R )₂ or Si(R )₂.

In many embodiments, it is preferred that X and X' can be S, and Y, Y', can be N or CH so that no large substituents for the five membered rings of the hAr groups significantly interact sterically with the NDI groups so, as to prevent co-planar conformations of the NDI and hAr groups.

In some embodiments, hAr is a bivalent heteroaryl formed by linking five membered bivalent heteroaryls having the structure shown below, wherein a is an integer 1, 2, 3, or 4; such as for example a single thiophene group, as also shown below. In some embodiments, a is 1. In some embodiments, a is not 2.

In many embodiments of the hAr is a bivalent fused heteroaryl having any one of the structures shown below;

wherein X, X', Y, Y', Y", Y"', Z and Z' can be defined in any of the ways described above.

In some embodiments, the hAr divalent fused heterocycles are selected from the structures shown below:

wherein X, X\ Y, Y', Y", Y'", Z and Z' can be defined in any of the ways described above.

Specific examples of such divalent fused hAr groups include those shown below:

In related embodiments, the hAr heteroaryls is:

Carbonyl bridged fused bivalent heteroaryls such as

2,6-divatent-4H<yciopenta[1 ,2- 2 , e-dtvaten H-cyctopenta

d:5,4-toldlftiophef>4-one [2,1-t>;3,4Jdithiazol& -one

Bis-a-dicarbonyl bridged fused heteroaryls such as

2.7-divelent- benzo(2.i-b:3_r4- 2J-dival©nt-benzo[2. l -b.

b ditNopherte-4 _»5-dione 3_t *b>tJithsazQle-4,5-diorie

2,6-dlvalent benzo 2M R imt-bBmo

11,2-6:5,4-61 {1,2-d;4,5-cfl djthiophene-4,3-dfone d¾ iopheris-4,8-d (one bis.(t lazole)-4,Mione or

Divalent bisheteroaryl substituted malononitriles such as

2-{2,6-divaient- H-cyc⁽openta 2-(2,5-<Jlva!#nt.7H-C clop©nta

[1 ,2-6:5,4^»ft']«itilophe«-4-ylW«e} {1 ,2-d:4.3-tf 1bis(thkaE0le)-7-ytlden«}

matononitriie malonortitrita

Divalent trisheteroaryl bridged dimalononitriles such as

2,Z-{2,6-dlvaIent benzo

P .2-d;4,S-<ilbss(thia2ole)- ,8^Wl ton«Wimaior»oitftie 4,8 Hy«dene}dim8tonon{trile 4,8- Jiyiidene) iimalGn«i^;Hri«

Oligomeric divalent thienopyrrolediones such as

Tl

5-substituted-1 divaleot-

4«*ieno(3,4-c]p rrol»- ,6(5H>-d«one

wherein R is a Q-C₂₀ normal or branched, alkyl, perfluoroalkyl, aryl, heteroaryl, alkyl-aryl, and alkyl-heteroaryl group, optionally substituted with one or more fluoro, cyano, alkyl, alkoxy groups. In many embodiments, R⁸ is a Cj- C₂o normal or branched alkyl or perfluoroalkyl group.

or heteroaryl derivatives such as

wherein Y, Y', Y" and Y'" are N or CR⁷, and R⁷ is hydrogen or a Ci-C₂₀ normal or branched, alkyl or perfluoroalkyl group, wherein the alkyl group is optionally substituted with one or more fluoro, cyano, alkyl, alkoxy groups. In one embodiment, the thiophene moieties are further substituted with one or more fluoro, cyano, alkyl, alkoxy groups, such as for example, a C|-C₂o normal or branched, alkyl or perfluoroalkyl group.

Bicyclic derivatives such as

wherein Y and Y' are N or CR , and R is hydrogen or a C1-C20 normal or branched, alkyl or perfluoroalkyl group, wherein the alkyl group is optionally substituted with one or more fluoro. cyano, alkyl, alkoxy groups and X and X' is independently selected from O, S, Se, or NR⁶, wherein R⁶ is a C1-C30 organic group, such as for example an independently selected normal, branched, or cyclic alkyl, fluoroalkyl, aryl. heteroaryl, alkyl-aryl. and alkyl-heteroaryl groups, which can be optionally substituted with one or more fluoro, cyano, alkyl, alkoxy groups. In one embodiment, Y and Y' are N and X and X' are O, S, Se, or NR⁶, in another embodiment, X and X' are S.

For example, X can comprise a fused ring moiety. A "fused ring" or a "fused ring moiety" can refer to a polycyclic or polyaryl or polyheteroaryl ring group having at least two rings where at least one of the rings is aromatic and such aryl or heteroaryl ring has a bond in common with at least one other ring that can be aromatic or non-aromatic, and carbocyclic or heterocyclic. These polycyclic ring systems are often planar and π-conjugated, and include optionally substituted bicyclic and tricyclic fused heteroaryl compounds. In many embodiments of the various inventions disclosed herein, the oligomers and/or compounds described comprise within their structure fused heteroaryl groups that can include the π-conjugated bicyclic and tricyclic heteroaryl groups shown below, wherein a dashed line represents a bond to another grou .

or

wherein; each X and X' is independently selected from O, S, Se, or NR⁶, wherein R⁶ is a terminal organic group; each Y, Y', Y" and Y"' is

7 7

independently selected from N, and CR , where R is hydrogen, halide, or a terminal organic group; each Z and Z' is independently selected from O, S, Se, C(R⁸)₂, Si(R⁸)₂, NR⁸, (CO), (CO)₂ or C=C(CN)₂, wherein R⁸ is a terminal organic group.

It is understood that the dashed lines (— ) represent a covalent bond. In one embodiment, the covalent bond is a between the aryl or heteroaryl moiety and the NDI moiety. Some aryl or heteroaryl moieties comprise more than one dashed line covalent bond; these embodiments can comprise one covalent bond to a NDI moiety and optionally another covalent bond to a moiety other than an NDI moiety, such as, for example, H, CN, or acyl. The acyl moiety may be

wherein Z can be, for example, optionally substituted C1 -C30 alkyl, aryl, heteroaryl, acyl, alkoxy, vinyl, and alkynyl, and the R groups, independently, are each a C1-C30 normal, branched, or cyclic alkyl, aryl, heteroaryl, alkyl-aryl, or alkyl-heteroaryl group optionally substituted with one or more halide, cyano, alkyl, or alkoxy groups. In another embodiment, Z may be independently an aryl group, wherein the aryl group comprises at least one fluoro or fluorinated substituent. In one embodiment, the two Z groups are each independently an aryl group, wherein the aryl group comprises at least one trifluoromethyl substituent. In one embodiment, the Z group is an optionally substituted alky or aryl group. In one embodiment, the Z group is an aryl group, and the aryl group comprises a fluoro or fluorinated substituent.

Again, while NDI compounds are a preferred embodiment herein, higher rylene compounds such as PDI and related perylene compounds can be also funetionalized with tin substituents and reacted to form additional compounds, such as oligomers and compounds as described herein in Part V, for use in, for example, organic electronic devices. Rylene compounds and moieties are known in the art. See, for example, Zhan et al., Adv. Mater., 201 1 , 23, 268-284.

Besides NDl and PDI, other known rylene compounds include TDI, QDI, 5DI, and HD1, for example.

Methods of making DI-Ar Compounds

NDI oligomers and polymers of the present embodiments can be prepared via homo- or cross-coupling of the NDI-tin compounds described herein. Cross coupling with stannyl substituents via Stille coupling is well known in the art. One embodiment provides for a method comprising: reacting at least one first naphthalene diimide (NDI) compound comprising at least one stannyl substituent bonded to the naphthalene moiety of the NDI compound in a coupling reaction with to form at least one bond between the NDI compound and an electron poor aryl or heteroaryl compound that is not an NDI compound. In one embodiment, the at least one first naphthalene diimide (NDI) compound comprises at least two stannyl substituents bonded to the naphthalene moiety of the NDI compound. In another embodiment, the electron poor aryl or heteroaryl compound is a heteroaryl compound. In another embodiment, the resulting oligomer or polymer is represented by a compound or composition the embodiments herein. Other embodiments are contained herein, such as those found in the Working

Examples.

Applications

References cited herein relate to applications of the compounds and materials. For example, the compositions, compounds, and materials described herein can be used in a variety of organic electronic applications including, for examples, field-effect transistors, OLEDs, displays, lighting, photovoltaic cells, sensors, light emitting transistors, and the like. Vacuum deposition and solution processing can be carried out. Inks can be formulated with use of solvents and additives. The working examples below provide further embodiments for applications and performance parameters.

OFETs are an important application including use of flexible and/or polymeric substrates. For example, N-channel organic transistors can be made. The electron mobility value can be, for example, at least 0.1, or at least 0.2, or at least 0.3 cmV'S^"1. Additional embodiments are provided in the following non-limiting working examples.

Working Examples

Materials and General Methods

Materials. Starting materials were reagent grade and were used without further purification unless otherwise indicated. Solvents were dried by passing through columns of activated alumina (toluene, CH₂C1₂), by distillation from Na/benzophenone (THF), or were obtained as anhydrous grade from Acros Organics. .V_l.V'-Di(«-hexyl)naphthalene- l ,4,5,8-bis(dicarboximide), 9, was synthesized according to the literature: (1) Rademaeher. A.; Markle, S.;

Langhals, H. Chem. Ber. 1982, 115, 2927. (2) G. Hamilton, D.; Prodi, L.; Feeder, N.; K. M. Sanders, J. J. Chem. Sac., Perkin Trans. 1 1999, 1057. (3) Reczek, J. J.; Villazor, K. R.; Lynch, V.; Swager, T. M.; Iverson. B. L. J. Am. Chem. Soc. 2006, 128, 7995.

Hexabutyltin was obtained from Sigma- Aldrich.

Characterization. Chromatographic separations were performed using standard flash column chromatography methods using silica gel purchased from Sorbent Technologies (60 A, 32-63 μκι). Ή and ^l3C{'H} NMR spectra were obtained on a Broker AMX 400 MHz Spectrometer with chemical shifts referenced using the Ή resonance of residual CHC1₃ or the C resonance of CDCI3 unless otherwise indicated. Electrochemical measurements were carried out under nitrogen in dry deoxygenated 0.1 M tetra-n-butylammonium

hexafluorophosphate in dichloromethane using a conventional three-electrode cell with a glassy carbon working electrode, platinum wire counter electrode, and a Ag wire coated with AgCl as pseudo-reference electrode. Potentials were referenced to ferrocenium/ferrocene by using decamethylferrocene (-0.55 V vs. ferrocenium / ferrocene) as an internal reference. Cyclic voltammograms were recorded at a scan rate of 50 mVs^"1. UV-vis-NIR spectra were recorded in 1 cm cells using a Varian Cary 5E spectrometer. Mass spectra were recorded on an Applied Biosystems 4700 Proteomics Analyzer by the Georgia Tech Mass Spectrometry Facility. Elemental analyses were performed by Atlantic

Microlabs.

Fabrication of Thin-Film Transistors. OFETs with bottom contact and top gate structure were fabricated on glass substrates (Eagle 2000 Corning). Au (50 nm) bottom contact source / drain electrodes were deposited by thermal evaporation through a shadow mask. The organic semiconductor layer was formed on the substrates by spin coating a solution prepared from 1 ,1 ',2,2'- tetrachloroethane (15 mg / raL) at 500 rpm for 10 sec and at 2000 rpm for 20 sec. A CYTOP (45 nm) / AI O3 (50 nm) bi-layer was used as top gate dielectric. The CYTOP solution (CTL-809M) was purchased from Asahi Glass with a concentration of 9 wt.%. To deposit the 45-nm-thick fluoropolymer layer, the original solution was diluted with solvent (CT-solv.180) to have solution:solvent ratios of 1 :3.5. The CYTOP layers were then deposited by spin coating at 3000 rpm for 60 sec. AI2O3 (50 nm) films were deposited on CYTOP layers by atomic layer deposition (ALD) at 1 10 °C using alternating exposures of trime hyl aluminum and ¾0 vapor at a deposition rate of approximately 0.1 nm per cycle. All spin coating and annealing processes were carried out in a N₂-filled dry box. Finally, Al (150 nm) gate electrodes were deposited by thermal evaporation through a shadow mask. All current- voltage (I-V) characteristics were measured with an Agilent E5272A source/monitor unit in a Na-filled glove box (0₂, H₂0 < 0.1 ppm).

EXAMPLE 1: PREPARATION OF COMPOUNDS 3, 4

Scheme 1.

1 : X = H 3: X = H (Yield 90 %)

2: X = Br 4: X = SnBu₃ (Yield 48%)

N, N '-di(«-hexyl)-2-tri-(n-butyl)stannylnaphthalene- 1,4,5,8- bis(dicarboximide), 3, and N,iV'-di(n-hexyl)-2,6-bis(tri(n- butyl)stannyl)naphthalene-l,4,5,8-bis(dicarboximide), 4, were obtained in good to moderate yields, respectively, according to Scheme 1. A mixture of the appropriate mono- or dibromo derivative, 1 or 2, and hexabutylditin (1 eq per bromo substituent) was heated in toluene in the presence of Pd₂dba₃ (0.05 eq per bromo) and P(o-tol)₃ (0.2 eq per bromo). Purification of the reaction products by silica gel chromatography and recrystallization from methanol afforded the mono- and distannyl derivatives as long yellow needles; these compounds were characterized by NMR spectroscopy, mass spectrometry, elemental analysis, and, in the case of 4, X-ray crystal structure. In comparison, under identical conditions, the monobrominated perylene diimide (PDI) derivative undergoes homocoupling to yield the bi-PDI product and the stannyl PDI intermediate could not be isolated.

The ability to isolate and thoroughly purify the distannyl derivative is important for applications in conjugated-polymer syntheses, where the ability to obtain high-molecular-weight material is critically dependent on precise control of monomer stoichiometry.

EXAMPLE 2: ALTERNATIVE PREPARATION METHOD; SYNTHESIS

OF 5 AND 6

Scheme 2.

The different chromatographic behavior of 3 and 4 (3: Rf = 0.3 on silica, eluting with 1 : 1 dichloromethane / hexanes; 4: Rf - 0.3 on silica, eluting with 1 : 10 dichloromethane / hexanes) suggested the possibility of carrying out this reaction using a mixture of mono- and dibromo species obtained from

bromination and imidization of NDA, only purifying at the final stage. This transformation can indeed be carried out without separation of the mono- and difunctionalized intermediates to give isolated yields of mono- and distannyl derivatives of ca. 20% and 5%, respectively (when using 1 eq. DBI as the brominating agent). The relative yields can be somewhat tuned with respect to the brominating agent and yields of ca. 10% were obtained for both mono- and distannyl derivatives using 2.1 eq. of DBI.

As shown in Scheme 2, in addition to 3 and 4, their NN'-bis(n-dodecyl) analogues 5 and 6 have also been obtained in similar isolated yield. The dodecyl group can improve solubility compared to, for example, a hexyl group.

The facile separation of the highly soluble mono- and distannyl NDI products via column chromatography is an attractive alternative to the more difficult purification of that of the mono- and dibromo-NDI intermediates, such as 1 and 2, which are both less soluble in common organic solvents and less well-differentiated in Rf (0.4 and 0.3 for 1 and 2 on silica, eluting with dichloromethane). As such, a two-step isolation and purification of the brominated species followed by stannylation results in overall yields of ca. 9% and 2% for the mono- and distannyl NDI, respectively.

EXAMPLE 3 :

2-Bromo-7-pentatluorobenzoyl-benzo[2, 1 -b: ,4-b ^']dithiophene-4,5-bis- ethyleneoxolane (-80% purity, -0.42 mmol, 0.244 g), ;V,.Y-bis(2-oetyklodeeyl)- 2,7-bis(tributylstannyl)-naphthalene 1 ,4-5,8-tetracarboxylic diimide (0.2 mmol, 0.281 g) were mixed with Pd(PPh₃)₄ (17 mol%, 0.034 mmol, 0.040 g) and Cul (10 mol%, 0.02 mmol, 0.004 g) under nitrogen atmosphere in an oven-dried flask equipped with magnetic stirbar. Anhydrous DMF (20 mL) was added and the resulting mixture was heated to reflux for a few minutes. The yellow-orange mixture became dark red. The reaction mixture was allowed to cool to room temperature, treated with water, and the organic matter was extracted with chloroform. Combined organic phases were dried over MgS0₄ and organic solvents were removed by rotary evaporation to give crude product (some residual DMF was still present). This crude material was purified by column chromatography (-200 mL of silica gel, CH2CI2 as eluant), and fractions with the desired product (still contaminated) were combined, the solvent was removed and dark red solid (0.227 g) was further purified by column chromatography (150 mL of silica gel, CI^CkEtOAe (200:1). Combined fractions with pure product were combined (red wine color), the solvents were removed by rotary evaporation and purple film was obtained (0.136 mg, 41.2% yield). Ή NMR (CDCI₃, 400 MHz): £8.82 (s, 2H), 7.57 (s, 2H), 7.48 (s, 2H), 4.22 (m, 8H), 4.09 (d, J= 7.3 Hz, 4H), 3.87-3.73 (two overlapping m, 8H), 1.94 (poorly resolved m, 2H), 1.45-1.15 (m, 64H), 0.85 (m, 12H); ^I3C { 'H} NMR (CDC1₃, 100 MHz): δ 175.7, 162.2, 143.9, 142.8, 140.6, 139.8, 138.6, 137.6, 136.3 (CH), 134.2, 134.0 (CH), 128.0 (CH), 127.8, 125.8, 123.4, 92.9, 92.7, 61.8 (CH₂), 61.5 (CH₂), 45.2 (CH₂), 36.7 (CH), 31.9 (C¾), 31.7(1) (CH₂), 31.68 (C¾), 30.1, 29.6(4), 29.5(8), 29.3(2) (CH₂), 29.2(9) (CH₂), 26.5 (CH₂), 22.7 (CH₂), 14.1 (CH₃) (carbon signals of the pentafluorophenyl group were not observed due to C-F coupling; several aliphatic carbon signals are missing due to overlap). F NMR (CDCI₃, 376.3 MHz): S -139.3 (poorly resolved m, 4F), -147.9 (poorly resolved tt, J= 20.7 Hz, 2F), -158.4 (m, 2F) ( 1 .1 ,2-trichlorotrifluoroethane was used as a reference with S at -71.75 ppm (t)). MS (MALDI) calculated for (C₉6H₁o4F,oN₂0₁₄S4+H) 1827.6289; found 1827.6139. Anal. Calcd. For C96H104F10N2O14S4: C, 63.07, H, 5.73, N, 1.53. Found; C, 63.05; H, 5.75, N, 1.53.

Additional characterization for this compound can be found in US

Provisional Application 61/579,608 filed December 22, 2011.

EXAMPLE 4:

N,N-Bis(2-octyldodecyl)-2,7-bis-(7-pentafluorobenzoyl-benzo[2, 1-^:3,4- b ']dithiophene-4,5-ethyleneoxolane-2-yl -naphthalene 1 ,4-5,8-tetracarboxylic diimide (0.104 mmol, 0.190 g) was mixed with 50 mL of acetic acid, heated to reflux and HCI (2~5 mL) was added to the dark red reaction mixture. The reaction mixture became lighter in color and then after a few minutes precipitate formed. The reaction mixture was refluxed for 1 h, cooled to room temperature and treated with water. Pink-red precipitate was separated by vacuum filtration, washed with water and dried. This crude product was purified by column chromatography (100 mL of silica gel, dichloromethane:ethyl acetate (100: 1) as eluant). First three fractions with diluted slightly contaminated product were kept separately, and the rest of the fractions were combined separately, the solvent was removed and the residue was further purified by two successive column chromatography purifications (150 mL of silica gel,

dichloromethane:ethyl acetate (100:1) as eluant). First fractions (after the second column) were kept separately, and the fractions with majority of the product were combined and subjected to rotary evaporation (70.3 mg).

Ή NMR (CDCI₃, 400 MHz): 8.80 (s, 2H), 7.87 (s, 2H), 7.73 (s, 2H), 4.09 (d, J = 7.2 Hz, 4H), 8H), 1.94 (poorly resolved m, 2H), 1.45-1.20 (m, 64H), 0.85 (m, 12H); ¹³C{'H} NMR (CDCI₃, 100 MHz): δ 176.5, 173.8, 173.2, 162.0, 161.7, 1 50.7, 145.1 (m), 144.4, 143.0, 142.6 (m), 142.3, 137.3, 137.2, 136.6 (m), 136.0 (CH), 134.7 (CH). 128.6 (CH), 128.0, 126.2, 124.2, 1 12.3 (m), 45.3 (CH₂), 36.6 (CH), 31.9 (CH₂), 31.54 (CH₂), 31.52 (CH₂), 30.1 (CH₂), 29.6 (CH₂), 29.3 (CH₂), 29.2(9) (CH₂), 26.3 (CH₂), 22.7 (CH₂), 14.1 (CH₃). ¹⁹F NMR (CDC1₃, 376.3 MHz): δ -139.3 (poorly resolved m, 4F), -147.9 (poorly resolved tt, J = 20.8 Hz, 2F), - 1 8.4 (m, 4F) ( 1 , 1 ,2-trichlorotrilluoroethane was used as a reference with S at -71.75 ppm (t)). HRMS (MALDI) calculated for

(C8₈HgsFioN₂OioS4+H) 1651.5240, found 1651.5071 (analyses were acquired for the previously obtained batch). Anal. Calcd. For Cg₈H₈₈FioN₂OioS4: C, 63.98; H, 5.37; N, 1.70. Found: C, 64.09; H, 5.25, N, 1.65.

Additional characterization for this compound can be found in US

Provisional Application 61/579,608 filed December 22, 201 1.

EXAMPLE 5:

19

A solution of 2-bromo-5-cyanothiazole (0.39 g, 2.07 mmol), 2,7-dihexyl-

4,9-bis(tributylstannyl)benzo[lmn][3,8]phenanthroline-l,3,6,8(2H,7H)-tetraone (1.00 g, 0.98 mmol), and copper(I) iodide (0.038 g, 0.197 mmol) in DMF (12 mL) was degassed with nitrogen for 5 minutes.

Tetrakis(triphenylphosphine)palladium (0.1 14 g, 0.098 mmol) was added and the reaction mixture was heated to 120 °C under nitrogen for 60 minutes. After cooling, the reaction mixture was dropped into methanol (100 mL), and precipitate was collected by filtration. The crude product was purified by column chromatography (silica gel, 5% ethyl acetate in dichloromethane). The product was recrystallized multiple times from ethylacetate and collected as a yellow solid. Yield: 0.37 g (65%). Ή NMR (300 MHz, CDC1₃): δ 9.03 (s, 2H), 8.48 (s, 2H), 4.10 (t, J= 7.5 Hz, 4H), 1.75-1.61 (m, 4H), 1.42-1.24 (m, 12H), 0.87 (t, J = 7.2 Hz, 6H). ¹³C{'H} NMR (75 MHz, l,l,2,2-tetrachloroethane-d₂, 60 °C): δ 168.40, 161.56, 160.95, 151.40, 136.87, 134.99, 127.65, 126.20, 124.39, 11 1.28, 109.40, 41.34, 31.17, 27.67, 26.44, 22.30, 13.80. LRMS (MALDI) m z [M]⁺ calc for 651; found, 653 [M+2H]⁺. Anal. Calcd. For C₃₄H₃oN₆0₄S₂: C, 62.75; H, 4.65; N, 12.91. Found: C, 62.75; H, 4.56; N, 12.92. OFET testing: Compound 19 showed n-channel field-effect transistor behavior. Saturation electron mobility as high as 0.012 cnT/Vs was observed for the best device. Average electron mobility value of 5.3(±4.3)x l0^"3 em²/Vs (over 8 devices of same dimensions and substrate), average threshold voltage of -0.9±- .0.9 V. and current on/off ratio of 10³ was observed.

EXAMPLE 6: poly{ | N , N '- di(n-dodecy l)-naphthalene- 1 ,4,5,8- bis(dicarboximide)-2,6-diyl|-alt-5,5 '-3,6-bis(4-dec lthiophen-2-yl)- 1,2,4,5- -l-17c)

In a microwave vial, equimolar amounts of N,N'-di(n-dodecyl)-2,6- bis(tri(n-butyl)stannyl)naphthalene-l,4,5,8-bis(dicarboximide) (0.19 mmol, 235 mg) and 5,5'-dibromo-3,6-bis(4-decylthiophen-2-yl)-l,2,4,5-tetrazine (0.19 mmol, 129 mg) were added and followed by addition of

tetrakis(triphenylphosphine)palladium(0) (0.01 mmol, 12 mg) and Cul (0.0025 mmol, 0.5 mg). The vial was then transferred to the glove-box, added anhydrous o-xylene (1 mL) and securely sealed. The glass vial was placed into a microwave reactor and heated at 170 °C for 2 h. After being cooled to room temperature, the vial was transferred to the glove-box, added 0.25 ml of bromobenzene and sealed securely again. The glass vial was placed into a microwave reactor and heated at 170 °C for 15 min. Then the reaction mixture was precipitated into a mixture of methanol and stirred for 1 hour at RT. The precipitate was filtered and was under extraction (Soxhlet) with methanol, acetone, chloroform and toluene. Finally, the polymer dissolved in chloroform was purified by size exclusion column chromatography over Bio-Rad Bio-Beads S-Xl eluting with chloroform. The polymer Qs-l-17c was recovered as a purple solid from the chloroform fraction by rotary evaporation (79 mg, 37%). The polymers dissolved in toluene will be precipitated in methanol, got a purple solid (19 mg, 9%) without HNMR, GPC and CHN analysis characterization. 1H NMR (300 MHz, CDC1₃) δ 8.80 (br, 2H), 8.31 (br, 2H), 4.12 (br, 4H), 2.48 (br, 4H), 1.66 (br, 8H), 1.24 (br, 64H), 0.86 (br, 12H). GPC: Mn 11.9 kDa; Mw 33.9 kDa; Mw/Mn 2.9. Anal. Calcd. for (C₆xH_%N₆0₄S₂) _n: C, 72.56; H, 8.60; N, 7.47. Found: C, 72.33; H, 8.67; N, 6.95%

EXAMPLE 7: poly{[ N , N '-bis(2-octyldodecyl)-naphthalene-l,4,5,8- bis(dicarboximide)-2,6-diyl]-alt^^

(QS-l-55a)

In a microwave vial, equimolar amounts of Ν,Ν'- bis(2-octyldodecyl)- 2.6-bis(tri(n-butyl)stannyl)naphthalene- 1 ,4,5,8-bis(dicarboximide) (0.6 mmol, 843 mg) and 5,5'-dibromo-3,6-bis(thiophen-2-yl)- l ,2,4,5-tetrazine (0.6 mmol, 242 mg) were added and followed by addition of

tetrakis(triphenylphosphine)palladium(0) (0.03 mmol, 34.7 mg) and Cul (0.008 mmol, 1.5 mg). The vial was then transferred to the glove-box, added anhydrous o-xylene (3 mL) and securely sealed. The glass vial was placed into a microwave reactor and heated at 170 °C for 2 h. After being cooled to room temperature, the vial was transferred to the glove-box, added 0.75 ml of bromobenzene and sealed securely again. The glass vial was placed into a microwave reactor and heated at 170 °C for 15 min. Then the reaction mixture was precipitated into a mixture of methanol and stirred for 1 hour at RT. The precipitate was filtered and was under extraction (Soxhlet) with methanol, acetone and chloroform. Finally, the polymer was purified by size exclusion column chromatography over Bio-Rad Bio-Beads S-Xl eluting with chloroform. The polymer was recovered as a purple solid from the chloroform fraction by rotary evaporation (420mg, 69%). Ή NMR (300 MHz, CDC1₃) δ 8.87 (br, 2H), 8.41 (br, 2H), 7.44 (br, 2H), 4.12 (br, 4H), 1.99 (br, 2H), 1.24 (br, 64H), 0.85 (br, 12H). GPC; Mn 9.5 kDa; Mw 16.2 kDa;

Mw/Mn 1.7. Anal. Calcd. for

C, 71.87; H, 8.29; N, 7.86.

Found: C, 71.85; H, 8.24; N, 7.1 1%. EXAMPLE 8: poly{[ N , N '-bisdodec l-naphthalene- 1,4,5,8- bis(dicarboximide)-2,6-diyl|-alt-2,5-thiazolo[5,4-d]thiazole}. (QS-2-5a-C and

-2-5a-DCB)

In a microwave vial equimolar amounts of N,N'-di(n-dodecyl)-2,6- bis(tri(n-butyl)stannyl)naphthalene-l,4,5,8-bis(dicarboximide) (0.1 mmol, 1 18.2 nig) and 2,5-Dibromothiazolo[5,4-d]thiazole (0.1 mmol, 29.8 mg) were added and followed by addition of tctrakis(triphenylphosphine)palladium(0) (0.005 mmol, 5.8 mg) and Cul (0.01 mmol, 1.9 mg). Then the vial was transferred to the glove-box, added anhydrous o-xylene (1 mL) and securely sealed. The glass vial was placed into a microwave reactor and heated at 170 °C for 2 h. After being cooled to room temperature, the vial was transferred to the glove-box, added 0.25 ml of bromobenzene and sealed securely again. The glass vial was placed into a microwave reactor and heated at 170 °C for 15 min. Then the reaction mixture was precipitated into a mixture of methanol and stirred for 1 hour at RT. The precipitate was filtered and was under extraction (Soxhlet) with methanol, acetone, hexane, chloroform and dichlorobenzene. The polymer QS-2-5a-C (34 mg, 45%) distilled by CHC1₃ was recovered as a purple solid from the chloroform fraction by rotary evaporation. The polymer QS-2-5a-DCB (25 mg, 25%) distilled by dichlorobenzene was recovered as a purple solid from the dichlorobenzene fraction by rotary evaporation. QS-2-5a-C: ^lH NMR (CDCI3, 300 MHz): δ 9.10 (b, 1 H), 8.62 (b, 1H), 4.17 (b, 4H), 1.70-1.25 (b, 40H), 0.86 (b, 6H). GPC: Mn 10.6 kDa; Mw 55.8 kDa; Mw/Mn 5.3. Anal. Calcd. for (C₄₂H₅2N4O4S2)„: C, 68.08; H, 7.07; N, 7.56. Found: C, 67.86; H, 6.91 ; N, 7.30%. QS-2-5a-DCB: ^lH NMR (CDCI3, 300 MHz): δ 9.01 (b, 1H), 8.79 (b, 1H), 4.03 (b, 4H), 1.67-1.09 (b, 40H), 0.74 (b, 6H). Anal. Calcd. for

(C₄₂H5₂N₄0₄S2)„: C, 68.08; H, 7.07; N, 7.56. Found: C, 63.62; H, 6.58; N, 7.64%. EXAMPLE 9: poly{[ N , N '-bis(2-octvldodccyl)-naphthalene- 1,4,5,8- bis(dicarboximide)-2,6-diyl]-aIt-2,5-thiazolo[5,4-d]thiazole}. (QS-2-5d)

In a microwave vial equimolar amounts of Ν,Ν'- bis(2-octyldodecyl)- 2.6-bis(tri(n-butyl)stannyl)naphthalene- 1 ,4,5,8-bis(dicarboximide) (0.1 mmol, 140.5 mg) and 2,5-Dibromothiazolo[5,4-d]thiazole (0.1 mmol, 29.8 mg) were added and followed by addition of tetrakis(triphenylphosphine)palladium(0) (0.005 mmol, 5.8 mg) and Cul (0.01 mmol, 1.9 mg). Then the vial was transferred to the glove-box, added anhydrous o-xylene (1 mL) and securely sealed. The glass vial was placed into a microwave reactor and heated at 170 °C for 2 h. After being cooled to room temperature, the vial was transferred to the glove-box, added 0.25 ml of bromobenzene and sealed securely again. The glass vial was placed into a microwave reactor and heated at 170 °C for 15 min. Then the reaction mixture was precipitated into a mixture of methanol and stirred for 1 hour at RT. The precipitate was filtered and was under extraction (Soxhlet) with methanol, acetone, hexane, chloroform and dichlorobenzene. The polymer QS-2- 5d (90 mg, 90%) distilled by CHC1₃ was recovered as a purple solid from the chloroform fraction by rotary evaporation. QS-2-5d: Ή NMR (CDCI₃, 300

MHz): δ 9.19 (b, 1 H), 8.59 (b, 1H), 4.10 (b, 4H), 1.60-1.24 (b, 66H), 0.85 (b, 12H). GPC: Mn 26.3 kDa; Mw 111.9 kDa; Mw/Mn 4.3. Anal. Calcd. for

(C58H84N4O4S2)„: C, 72.16; H, 8.77; N, 5.80. Found: C, 70.63,; H, 8.47; N,

EXAMPLE 10 THE CHARACTERIZATION OF COPOLYMERS

Molecular weights of the polymers were determined by gel permeation chromatography (GPC) using polystyrene standards as calibrants (Table 1. The number-average molecular weights (Mn) of these polymers are between 9,500 and 26,300, with a large polydispersity index PDI (Mw/Mn). The thermal properties of the polymers were determined by thermogravimetric analysis (TGA) under nitrogen (Figure lc and 2c). The copolymers based on NDI and tetrazine showed a good thermal stability with decomposition temperature ca. 290 °C (Table 1. Table ί The GPC data of NDI-based Copolymers

compound Mn / kDa Mw / kDa PDI DP T / °C

QS-l -17c 1 1.9 33.9 2.9 1 1 287

QS-l -55a 9.5 16.2 1.7 9 291

QS-2-5ci-C 10.6 55.8 5.3 14 -

QS-2-5a-DCB - - - - -

QS-2-5d 26.3 1 1 1.9 4.3 27 -

The spectra of optical absorption of copolymers (QS-l - 17c, QS-l -55a, QS-2-5a-C, and QS-2-5d) were measured in chloroform solutions (10 ⁶ M) and thin solid films (dropping from chloroform solutions), and the spectra of optical absorption of copolymer QS-2-5a-DCB was measured in dichlorobenzene solution (10 ⁶ M) and thin solid films (dropping from dichlorobenzene solutions). Table 2 summarizes the optical properties. The absorption spectra of copolymers exhibit two absorption bands corresponding to π-π* transition and intramolecular charge transfer. In the solution and film, the absorption corresponding to π-π* transition exhibit almost the same maximal absorption wavelengths which is ca. 390 nm. In the film, the maximal absorption wavelength of polymers (QS-l -55a, QS-2-5a-C, QS-2-5a-DCB and QS-2-5d) corresponding to intramolecular charge transfer exhibit 50 to 60 nm redshifts relative to the solution, and only polymer QS- 1 - 17c didn't exhibit too much redshift.

Cyclic voltammogram curves of the polymers are using polymer film in dichloromethane at a potential scan rate of 50 mV s^"1 and illustrated in the Figures. The two or three reversible reduced peaks are observed in the CV curves which can represent the reductions of NDI and tetrazine or thiazolothiazole. The first reduction potentials of QS-l -17c, QS-l -55a, QS-2-5a-C, QS-2-5a-DCB and QS-2-5d versus FeCp₂ " are -1.00, -1.01 , -1.01 , -0.81 and -0.96 V,

respectively. The corresponding calculated LUMO levels of those polymers are lower than the LUMO level of pure NDI, especially the one with larger molecular weights. This phenomenon indicates that the LUMO levels of semiconductors can be lowered by the introduction of electron withdrawing group and the linear extension of π electron system. Table 2 The Optical and Electrochemistry Properties of NDI-based

Copolymers

E_1/2 ^0/~ vs Ε,/ί¹- ² and Et/2^1" cnipd x_ma!£ V nm Amax / nm Cp₂Fe^{0 +} (V, ^a- vs Cp₂Fe^0/+ (V,

DCM) DCM)

QS-l-17c 387, 498 391 , 499 -1.00 -1.31

QS-l-55a 367, 385, 392, 531

-1.01 -1.30, -1.51

478

QS-2-5a-c 386, 488 389, 546 -1.01 -1.33, -1.49

QS-2-5a- 390, 574 -0.81 - 1.19

390, 514

DCB

QS-2-5d 387, 504 388, 559 -0.96 -1.24

EXAMPLE 11: Organic field effect transistor (OFET) characterization

Two of these copolymers (QS-l-17c and OS- 1 -55a) were tested for top-gate bottom-contact OFET device structure. These devices were fabricated on glass substrates (Eagle 2000 Coming). Au (50 nm) bottom contact source/drain electrodes were deposited by thermal evaporation through a shadow mask.

Organic semiconductor layers were formed on the substrates by spin coating with a solution (15 mg/mL of QS-I-55a and QS-I-17c in dicholorobenzene) at 500 rpm for 10 sec and at 2,000 rpm for 20 sec. These organic layers were annealed at 100 °C for 15 minutes on the hot plate inside nitrogen glove box. A CYTOP (45 nm)/Al₂O₃(50 nm) bi-layers was used as top gate dielectrics.

CYTOP solution (CTL-809M) was purchased from Asahi Glass with a concentration of 9 wt. %. To deposit the 45-nm-thick fluoropolymer layers, the original solution was diluted with their solvents (CT-solv.180) to have solution: solvent ratios of 1 :3.5. CYTOP layers were deposited by spin coating at 3000 rpm for 60 sec. A1₂0₃ (50 nm) films were deposited on fluoropolymer layers by atomic layer deposition (ALD) at 110 °C using alternating exposures of trimethyl aluminum [A1(CH₃)₃] and H₂0 vapor at a deposition rate of

approximately 0.1 nm per cycle. All spin coating and annealing processes were carried out in a N₂-filled dry box. Finally, Al (150 nm) gate electrodes were deposited by thermal evaporation through a shadow mask. All current-voltage (l- V) characteristics of OFETs were measured with an Agilent E5272A

source/monitor unit in a N₂-filled glove box (0₂, H₂0 < 0.1 ppm). Field-effect mobility values, μ, and threshold voltages, V_T, were measured in the saturation regime from the highest slopes of plots of |IDS|' ² vs. VGS according to the saturation-region current equation for a standard MOSFET: 1 W where Ci is the capacitance per unit area of the gate dielectric, and W and L are respectively the width and length of the semiconductor channel defined by the source and drain electrodes.

5 Figure I d and Figure le show the transfer and output characteristics of a

particular top-gate bottom-contact OFET of QS-I-17c respectively, with Au

source/drain electrodes { W/L^~ 2550 μηι/1 80 μιη). The operating voltage for these devices was 15 V. These devices show average electron mobility value of 7.7 X 10^"4 enr/Vs (averaged over 8 devices of same dimensions), average threshold voltage of 3. 1 V, and current on/off ratio of lxlO³.

Figure 2d and Figure 2e show the transfer and output characteristics of a particular top-gate bottom-contact OFET of QS-I-55a respectively, with Au

source/drain electrodes { W/L- 2550 μπι/180 μηι). The operating voltage for these devices was 15 V. These devices show average electron mobility value of 2.8 X 5 10^~4cm²/ s (averaged over 6 devices of same dimensions), average threshold

voltage of 2.7 V, and current on/off ratio of lxl 0³

Table 3 Summary of electrical parameters of top-gate bottom-contact OFET

Characteristics of NDI-based Copolymers

C S/D

cmpd W/L Solvent

(nF/cm²) electrode μ (cm fW s) V (V)

QS-i- 2550μητ/180 μηι 35.2 dichlorobenzene Au 7,7(±0.3) x lO 3.1 (±0.2) 1x10

17c (Device: SS-I- 81)

QS-1- 2550μηι/180 μηι 35.2 dichlorobenzene Au 2.8(±0.2) x lO^"4 2.7(±0.3) lxlO³

55a (Device: SS-I- 80)

0

Claims

C L A I M S

1. A compound represented by:

wherein each R independently is a Ci-C₃₀ normal, branched, or cyclic alkyl, aryl, heteroaryl, alkyl-aryl, or alkyl-heteroaryl group optionally substituted with one or more halide, cyano, alkyl, or alkoxy groups; and Ri, R₂, and R₃ are independently hydrogen or an organic radical; and n is 2 to 100, and X is an electron poor aryl or heteroaryl group.

2. The compound of claim 1, wherein the compound is represented by:

3. The compound of claim 1 , wherein the compound is represented by:

4. The compound of claim 1, wherein the compound is represented by:

5. The compound of claim 1, wherein the compound is represented by:

or

6. The compound of claims 1-5, wherein X is an electron poor aryl group.

7. The compound of claims 1-5, wherein X is an electron poor heteroaryl group.

8. The compound of claims 1-5, wherein the electron poor aryl or heteroaryl group, X, is one of:

wherein R¹⁴ is a C₁-C30 organic radical and R¹³ is hydrogen, halogen, or a C₁-C30 organic radical.

9. The compound of claim 8, wherein R¹⁴ is a Ci-Qs alkyl, perfluoroalkyl, or alkoxy group; and R ^~ is hydrogen, halogen, or a Q-Cis alkyl, perfluoroalkyl, or alkoxy group.

10. The compound of claims 1-9, wherein Ri, R₂, and R₃ are hydrogen.

1 1. The compound of claims 1-10, wherein the electron poor aryl or heteroaryl group, X, is one of:

R14

12. An ink composition comprising at least one solvent and at least one compound according to claims 1-11.

13. A device comprising at least one compound according to claims :

1-1 1.

14. The device of claim 13, wherein the device is an OLED, OPV,

OFET, or sensing device.

15. The device of claim 13, wherein the device is an OFET device.

16. The compound of claim 4, wherein the compound is a polymer having a number average molecular weight of at least 5,000 Da.