CN104744676B - Conjugated polymer containing 7H-pyrrolo- [3,4-g]-6,8-diketone of quinoxaline and application - Google Patents

Abstract

The invention discloses a conjugated polymer containing 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione and its application. Its structural formula is as follows; the copolymer prepared by the invention has fluorescence It has a wide absorption of sunlight, so it can be applied to the production of polymer light-emitting diode devices, as well as the active layer of polymer field effect transistors and polymer solar cells.

Description

Conjugated polymers containing 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione and their application

technical field

The invention relates to a new polymer used in the field of optoelectronic materials and devices, in particular to a novel conjugated polymer containing 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione and its Preparation and application.

Background technique

In the past ten years, organic solar thin-film batteries have been very popular, and the efficiency of organic thin-film batteries has also hit new highs frequently. At present, the highest efficiency of single-layer devices has exceeded 10%, and the market prospect is very bright. In order to obtain high-efficiency polymer solar cell devices, materials are one of the most important factors. Generally speaking, an ideal material should have broad absorption, high carrier mobility, and suitable energy level. So this requires us to innovate materials and develop more new conjugated polymer materials. Among many photoelectric materials, photoelectric materials containing quinoxaline groups or imide groups (such as benzimide) are widely used in organic electroluminescence, organic solar cells, chemical and biological sensors, and organic field effect transistors. has been widely applied. Due to the modifiability of the N atom of the benzimide group, alkyl chains of different shapes and lengths can be attached to the N atom to solubilize it, thereby improving the solubility and processability of the corresponding optoelectronic material. However, the chemical functional group of benzimide also has its limitations, mainly because its electron-withdrawing ability is not very strong, and it is difficult to form a wide-absorbing polymer after copolymerization with other aromatic groups.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the prior art. In order to further improve the optoelectronic performance of materials containing benzimide units, this patent combines benzimide and quinoxaline to provide a new type of fused ring photoelectric Material: 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione. The conjugated polymer is fluorescent and has broad absorption of sunlight.

Another object of the present invention is to provide a method for preparing the conjugated polymer containing 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione.

Another object of the present invention is to provide the conjugated polymer containing 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione in polymer light-emitting diodes, polymer field effect transistors and Applications in polymer solar cells.

The object of the present invention is achieved through the following technical solutions:

Conjugated polymers containing 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione with the formula:

Wherein, R ₁ , R ₂ and R ₃ are hydrogen atoms or alkyl chains; the alkyl chains are linear, branched or cyclic alkyl chains with 1 to 24 carbon atoms, or one or more of them Carbon atoms are replaced by oxygen atoms, alkenyl groups, alkynyl groups, aryl groups, hydroxyl groups, amino groups, carbonyl groups, carboxyl groups, ester groups, cyano groups or nitro groups, and hydrogen atoms are replaced by halogen atoms or the above functional groups; Ar is an aromatic group; Said n is a natural number from 1 to 10000, 0<x<1, 0<y<1, x+y=1. x and y are the relative content of 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione unit and aromatic group Ar in the conjugated polymer respectively; aromatic group Ar and 7H -pyrrolo[3,4-g]quinoxaline-6,8-dione is connected in a conjugated manner, and n is the degree of polymerization of the conjugated polymer.

The aromatic group Ar is one or more of the following structures:

Wherein, R, R _a to R _d are hydrogen atoms or alkyl chains. The R, R _a to R _d are linear, branched or cyclic alkyl chains with 1 to 24 carbon atoms, or wherein one or more carbon atoms are replaced by oxygen atoms, alkenyl, alkynyl, aryl , hydroxy, amino, carbonyl, carboxyl, ester, cyano or nitro, and hydrogen atoms are replaced by halogen atoms or the above functional groups.

The application of the conjugated polymer in the preparation of the light-emitting layer of the polymer light-emitting diode device, the preparation of the semiconductor active layer in the polymer field effect transistor or the preparation of the active layer of the polymer solar photovoltaic cell.

In the present invention, a variety of conjugated aromatic monomers are selected to perform Still coupling copolymerization with monomers containing 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione to obtain 7H-pyrrolo Conjugated polymers of [3,4–g]quinoxaline–6,8–dione.

The conjugated polymer containing 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione of the present invention can be prepared by the following method:

(1) With 4,7-bis(thiophene-2-yl)-1,2,5-benzothiadiazole-N-R _1-5,6 -dibasic carboxylic acid imide as the parent, by Iron powder reduction reaction to obtain 4,7-bis(thiophene-2-yl)-5,6-diamino-N-R ₁ base-isoindole-1,3-diketone, and then this monomer and even Acyl compounds undergo dehydration condensation reaction to synthesize 5,9-bis(thiophene-2-yl)-7-R _1-2 -R _2-3 -R _3-7H -pyrrolo[3,4-g ]quinoxaline–6,8–dione, and finally brominated by NBS to obtain the final monomer 5,9–bis(5–bromo–thiophene–2–yl)–7–R ₁ group–2–R ₂ group– 3-R ₃ -yl-7H-pyrrolo[3,4-g]quinoxaline-6,8-dione.

(2) Metal-catalyzed coupling reaction: the monomer containing Ar structure with metal-catalyzed coupling reaction active functional group reacts with the brominated product in step (1) under a metal catalyst to obtain a preliminary functionalized Ar structure and 7H-conjugated polymer of pyrrolo[3,4-g]quinoxaline-6,8-dione.

In step (2), 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione derivatives can be made to have good solution processability and photoelectric properties through the adjustment and transformation of Ar structure. 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione structure was introduced into the polymer to prepare a series containing 7H-pyrrolo[3,4-g]quinoxaline-6,8- Conjugated polymers of diketones.

The structures of small molecules and polymer materials were characterized by nuclear magnetic resonance (NMR) and gel chromatography (GPC), the spectral properties of polymer materials were tested by UV-vis spectrometer, and the prepared polymers were prepared into photoelectric devices to characterize them photoelectric performance.

Compared with traditional benzoimides, the electron-withdrawing ability of 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione of the present invention has been significantly improved, and it is expected to develop better performance Narrow Bandgap Solar Cell Materials. It can be predicted that the conjugated polymer materials containing 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione have good photoelectric properties and are a class of materials with commercial application prospects.

The structural formulas of benzoimide and 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione are as follows:

Conjugated polymer materials based on 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione as a class of promising optoelectronic materials have not been reported in this field so far. The present invention first synthesizes the conjugated polymer containing 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione and successfully applies it in the field of optoelectronics.

Compared with the prior art, the present invention has the following advantages:

The conjugated polymer containing 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione has a novel structure and originality. Conjugated polymers containing 7H-pyrrolo[3,4-g]quinoxaline-6,8-dione have multiple functions, are fluorescent, and can be used to make light-emitting layers of polymer light-emitting diodes; It has high mobility and can be applied to polymer field effect transistors; it can absorb sunlight and can be applied to the active layer of polymer solar cells, and the related solar cells have high energy conversion efficiency.

Description of drawings

Fig. 1 is the absorption spectrogram of polymer prepared in embodiment 4～7 in tetrahydrofuran solution;

Fig. 2 is the thin film absorption spectrum of polymer prepared by embodiment 4～7;

Fig. 3 is a J-V curve diagram of devices prepared from polymers obtained in Examples 4-7.

detailed description

In order to better understand the content of the present invention, the technical solutions of the present invention will be further described below through specific examples, including synthesis, characterization and device preparation, but not limited thereto.

Example 1

The preparation of 4,7-bis(thiophene-2-yl)-5,6-diamino-N-R ₁ -isoindole-1,3-dione, the reaction formula is as shown in formula I:

Synthesis of 4,7-di(thiophen-2-yl)-1,2,5-benzothiadiazole-N-R _1-5,6 -dibasic carboxylic acid imide (a) in formula I Refer to literature [Wang LX, Cai DD, Zheng QD, et al. ACS Macro Lett. 2013, 2, 605-608].

The preparation of 4,7-bis(thiophen-2-yl)-5,6-diamino-N-octyl-isoindole-1,3-dione is illustrated as an example. Add 4,7-bis(thiophen-2-yl)-1,2,5-benzothiadiazole-N-octyl-5,6-dibasic carboxylic acid imide (0.87g, 1.82mmol) and iron powder (1.22g, 21.8mmol), then add 30ml of glacial acetic acid, stir and reflux under nitrogen for 5h, then pour the reaction solution into water, a yellow-green solid precipitates, filter, take the filter residue, and use silica gel chromatography Column separation and purification gave yellow solid 4,7-bis(thiophen-2-yl)-5,6-diamino-N-octyl-isoindole-1,3-dione (0.6g, yield 73%) .

¹ H NMR (300MHz, CDCl ₃ ): δ=7.54(d,2H), δ=7.20(t,2H), δ=7.13(d,2H), δ=3.99(s,4H), δ=3.41( t,2H),δ=1.53(m,2H),δ=1.12-1.25(m,10H),δ=0.84(t,3H).

¹³ C NMR (151MHz, CDCl ₃ ) δ167.71, 138.53, 133.19, 128.57, 127.60, 127.54, 122.36, 117.76, 37.79, 31.75, 29.15, 29.12, 28.57, 26.95, 22.61, 14.08.

Then take the preparation of 4,7-di(thiophen-2-yl)-5,6-diamino-N-(2-ethylhexyl)-isoindole-1,3-dione as an example to illustrate. Add 4,7-di(thiophen-2-yl)-1,2,5-benzothiadiazole-N-(2-ethylhexyl)-5,6-imide (0.6g , 1.25mmol) and iron powder (0.83g, 14.97mmol), then add 30ml of glacial acetic acid, stir and reflux under nitrogen for 5h, pour the reaction solution into water, precipitate a yellow-green solid, filter, take the filter residue, and use silica gel chromatography Chromatography column separation and purification to obtain yellow solid 4,7-di(thiophen-2-yl)-5,6-diamino-N-(2-ethylhexyl)-isoindole-1,3-dione (0.42g , yield 75%).

¹ H NMR (300MHz, CDCl ₃ ): δ=7.54(d,2H), δ=7.20(t,2H), δ=7.13(d,2H), δ=3.99(s,4H), δ=3.34( d,2H),δ=1.70(m,1H),δ=1.20-1.22(m,8H),δ=0.81(m,6H).

¹³ C NMR (151MHz, CDCl ₃ ) δ167.98, 138.56, 133.26, 128.55, 127.63, 127.56, 122.29, 117.70, 41.82, 38.08, 30.57, 28.51, 23.93, 23.06, 14.06, 10.49.

4,7-bis(thiophen-2-yl)-5,6-diamino-N-alkyl-isoindole-1,3-dione is not limited thereto.

Example 2

5,9-di(thiophene-2-yl)-7-R ₁ base-2-R ₂ base-3-R ₃ base-7H-pyrrolo[3,4-g]quinoxaline-6,8- The preparation of diketone, reaction formula is shown in formula II:

To prepare 5,9-bis(thiophen-2-yl)-7-octyl-2,3-bis(4-octyloxyphenyl)-7H-pyrrolo[3,4-g]quinoxaline- 6,8-diketone is used as an example to illustrate. Add 4,7-bis(thiophene-2-yl)-5,6-diamino-N-octyl-isoindole-1,3-dione (0.38g, 0.83mmol) and 1 ,2-bis(4-octyloxyphenyl)ethane-1,2-diketone (0.42g, 0.87mmol), then add 45ml glacial acetic acid, stir and reflux under nitrogen overnight, then pour the reaction solution into water , extracted with dichloromethane. Dry the organic phase with anhydrous magnesium sulfate, filter, spin dry the organic phase, and then separate and purify with silica gel chromatography to obtain an orange solid 5,9-di(thiophene-2-yl)-7-octyl-2,3-di (4-octyloxyphenyl)-7H-pyrrolo[3,4-g]quinoxaline-6,8-dione (0.63 g, 86% yield).

¹ H NMR (300MHz, CDCl ₃ ): δ=7.68-7.74(m,4H), δ=7.60(d,4H), δ=7.25(t,2H), δ=6.83(d,4H), δ= 3.95(t,4H),δ=3.67(t,2H),δ=1.74(m,4H),δ=1.63(m,2H),δ=1.09-1.25(m,30H),δ=0.83(m ,9H).

¹³ C NMR(151MHz,CDCl ₃ )δ166.33,160.62,152.38,140.78,132.63,132.33,131.85,131.17,130.08,130.00,126.74,126.03,114.32,68.10,38.68,31.81,31.77,29.35,29.24,29.20,29.17 ,29.15,28.38,27.04,26.03,22.66,22.62,14.11,14.09.

Then to prepare 5,9-bis(thiophen-2-yl)-7-octyl-2,3-bis(3-octyloxyphenyl)-7H-pyrrolo[3,4-g]quinoxaline -6,8-dione as an example. Add 4,7-bis(thiophene-2-yl)-5,6-diamino-N-octyl-isoindole-1,3-dione (0.38g, 0.83mmol) and 1 ,2-bis(3-octyloxyphenyl)ethane-1,2-dione (0.42g, 0.87mmol), then add 45ml of glacial acetic acid, stir and reflux under nitrogen overnight, then pour the reaction solution into water , extracted with dichloromethane. Dry the organic phase with anhydrous magnesium sulfate, filter, spin dry the organic phase, and then separate and purify with silica gel chromatography to obtain an orange solid 5,9-di(thiophene-2-yl)-7-octyl-2,3-di (3-octyloxyphenyl)-7H-pyrrolo[3,4-g]quinoxaline-6,8-dione (0.66 g, 90% yield).

¹ H NMR (300MHz, CDCl ₃ ): δ=7.75(d,2H), δ=7.69(d,2H), δ=7.36(s,2H), δ=7.28(t,2H), δ=7.17( m,4H),δ=6.91(d,2H),δ=3.84(t,4H),δ=3.68(t,2H),δ=1.71(m,6H),δ=1.25-1.41(m,30H ),δ＝0.84(m,9H).

¹³ C NMR(151MHz,CDCl ₃ )δ166.18,159.09,152.76,140.99,138.84,132.79,132.55,130.99,130.02,129.21,127.19,126.14,122.67,117.32,115.32,68.10,38.76,31.85,31.77,29.34,29.30 ,29.16,29.15,29.13,28.36,27.04,26.05,22.70,22.62,14.13,14.09.

Then to prepare 5,9-bis(thiophen-2-yl)-7-(2-ethylhexyl)-2,3-bis(4-octyloxyphenyl)-7H-pyrrolo[3,4- g] quinoxaline-6,8-dione as an example. Add 4,7-bis(thiophene-2-yl)-5,6-diamino-N-(2-ethylhexyl)-isoindole-1,3-diketone (0.26g, 0.57mmol) and 1,2-bis(4-octyloxyphenyl)ethane-1,2-diketone (0.25g, 0.54mmol), then add 30ml of glacial acetic acid, stir and reflux under nitrogen overnight, and then The reaction solution was poured into water and extracted with dichloromethane. Anhydrous magnesium sulfate dried the organic phase, filtered, spin-dried the organic phase, and then separated and purified by silica gel chromatography to obtain an orange solid 5,9-bis(thiophene-2-yl)-7-(2-ethylhexyl)- 2,3-bis(4-octyloxyphenyl)-7H-pyrrolo[3,4-g]quinoxaline-6,8-dione (0.43 g, 86% yield).

¹ H NMR (300MHz, CDCl ₃ ): δ=7.71-7.73(m,4H), δ=7.65(d,4H), δ=7.28(t,2H), δ=6.83(d,4H), δ= 3.95(t,4H),δ=3.60(d,2H),δ=1.87(m,1H),δ=1.74(m,4H),δ=1.29-1.45(m,28H),δ=0.87(m ,12H).

¹³ C NMR(151MHz,CDCl ₃ )δ166.61,160.61,152.36,140.79,132.61,132.28,131.84,131.22,130.09,129.97,126.68,126.07,114.32,68.10,42.67,38.03,31.81,30.65,29.35,29.24,29.20 ,28.56,26.03,24.00,23.06,22.66,14.11,14.07,10.49.

Then to prepare 5,9-bis(thiophen-2-yl)-7-(2-ethylhexyl)-2,3-bis(3-octyloxyphenyl)-7H-pyrrolo[3,4- g] quinoxaline-6,8-dione as an example. Add 4,7-bis(thiophene-2-yl)-5,6-diamino-N-(2-ethylhexyl)-isoindole-1,3-diketone (0.43g, 0.95mmol) and 1,2-bis(3-octyloxyphenyl)ethane-1,2-diketone (0.42g, 0.9mmol), then add 50ml glacial acetic acid, stir and reflux under nitrogen overnight, and then The reaction solution was poured into water and extracted with dichloromethane. Anhydrous magnesium sulfate dried the organic phase, filtered, spin-dried the organic phase, and then separated and purified by silica gel chromatography to obtain an orange solid 5,9-bis(thiophene-2-yl)-7-(2-ethylhexyl)- 2,3-bis(3-octyloxyphenyl)-7H-pyrrolo[3,4-g]quinoxaline-6,8-dione (0.74 g, 88% yield).

¹ H NMR (300MHz, CDCl ₃ ): δ=7.75(d,2H), δ=7.69(d,2H), δ=7.36(s,2H), δ=7.28(t,2H), δ=7.15( m,4H),δ=6.91(d,2H),δ=3.85(t,4H),δ=3.62(d,2H),δ=1.88(m,1H),δ=1.71(m,4H), δ＝1.30-1.42(m,28H), δ＝0.88(m,12H).

¹³ C NMR(151MHz,CDCl ₃ )δ166.46,159.09,152.74,141.01,138.86,132.78,132.51,131.05,129.99,129.20,127.13,126.17,122.68,117.31,115.33,68.11,42.74,38.05,31.85,30.66,29.71 ,29.34,29.30,29.13,28.55,26.05,24.01,23.06,22.70,14.13,14.07,10.49.

5,9-di(thiophene-2-yl)-7-R ₁ base-2-R ₂ base-3-R ₃ base-7H-pyrrolo[3,4-g]quinoxaline-6,8- Diketones are not limited to this.

Example 3

5,9-bis(5-bromo-thiophen-2-yl)-7-R ₁ base-2-R ₂ base-3-R ₃ base-7H-pyrrolo[3,4-g]quinoxaline- The preparation of 6,8-diketone, the reaction formula is as shown in formula III:

To prepare 5,9-bis(5-bromo-thiophen-2-yl)-7-octyl-2,3-bis(4-octyloxyphenyl)-7H-pyrrolo[3,4-g] Quinoxaline-6,8-dione is used as an example to illustrate. Add 5,9-bis(thiophene-2-yl)-7-octyl-2,3-bis(4-octyloxyphenyl)-7H-pyrrolo[3,4-g]quinone into 100ml two-neck bottle Oxaline-6,8-diketone (0.63g, 0.71mmol), and then add 30ml of chloroform and 10ml of glacial acetic acid and stir well. NBS (N-bromosuccinimide, N-bromosuccinimide) (0.31 g, 1.71 mmol) was added under ice-bath conditions, and the reaction was carried out at room temperature for 24 h. The reaction solution was poured into water and extracted with dichloromethane. Dry the organic phase with anhydrous magnesium sulfate, filter, spin dry the organic phase, and then separate and purify with silica gel chromatography to obtain orange-red solid 5,9-di(5-bromo-thiophene-2-yl)-7-octyl- 2,3-bis(4-octyloxyphenyl)-7H-pyrrolo[3,4-g]quinoxaline-6,8-dione (0.57 g, 77% yield).

¹ H NMR (300MHz, CDCl ₃ ): δ=7.76(d,4H), δ=7.66(d,2H), δ=7.19(d,2H), δ=6.87(d,4H), δ=4.00( t,4H),δ=3.68(t,2H),δ=1.80(m,4H),δ=1.76(m,2H),δ=1.25-1.32(m,30H),δ=0.84(m,9H ).

¹³ C NMR(151MHz,CDCl ₃ )δ166.16,160.83,152.84,140.23,133.36,132.43,131.91,131.39,129.72,128.98,126.56,118.16,114.45,68.16,38.80,31.82,31.77,29.36,29.24,29.21,29.16 ,29.14,28.35,27.02,26.04,22.67,22.62,14.11,14.08.

Then to prepare 5,9-bis(5-bromo-thiophen-2-yl)-7-octyl-2,3-bis(3-octyloxyphenyl)-7H-pyrrolo[3,4-g ]Quinoxaline-6,8-dione as an example. Add 5,9-bis(thiophene-2-yl)-7-octyl-2,3-bis(3-octyloxyphenyl)-7H-pyrrolo[3,4-g]quinone into 100ml two-necked bottle Oxaline-6,8-diketone (0.66g, 0.75mmol), and then add 30ml of chloroform and 10ml of glacial acetic acid and stir well. NBS (N-bromosuccinimide, N-bromosuccinimide) (0.32 g, 1.8 mmol) was added under ice-bath conditions, and the reaction was carried out at room temperature for 24 h. The reaction solution was poured into water and extracted with dichloromethane. Dry the organic phase with anhydrous magnesium sulfate, filter, spin dry the organic phase, and then separate and purify with silica gel chromatography to obtain orange-red solid 5,9-di(5-bromo-thiophene-2-yl)-7-octyl- 2,3-bis(3-octyloxyphenyl)-7H-pyrrolo[3,4-g]quinoxaline-6,8-dione (0.57 g, 73% yield).

¹ H NMR (300MHz, CDCl ₃ ): δ=7.65(d,2H), δ=7.53(s,2H), δ=7.16-7.22(m,4H), δ=7.06(d,2H), δ= 6.98(d,2H),δ=3.98(t,4H),δ=3.70(t,2H),δ=1.70(m,6H),δ=1.25-1.33(m,30H),δ=0.84(m ,9H).

¹³ C NMR(151MHz,CDCl ₃ )δ166.03,159.45,153.07,140.21,138.47,133.68,132.17,131.49,129.17,129.02,126.94,122.80,118.49,117.96,114.83,68.24,38.88,31.86,31.77,29.41,29.30 ,29.14,28.35,27.02,26.17,22.70,22.62,14.14,14.09.

Then to prepare 5,9-bis(5-bromo-thiophen-2-yl)-7-(2-ethylhexyl)-2,3-bis(4-octyloxyphenyl)-7H-pyrrolo[ 3,4–g]quinoxaline–6,8–dione as an example. Add 5,9-bis(thiophene-2-yl)-7-(2-ethylhexyl)-2,3-bis(4-octyloxyphenyl)-7H-pyrrolo[3, 4-g] quinoxaline-6,8-dione (0.5g, 0.59mmol), then add 30ml chloroform and 10ml glacial acetic acid and stir well. NBS (N-bromosuccinimide, N-bromosuccinimide) (0.25 g, 1.41 mmol) was added under ice-bath conditions, and the reaction was carried out at room temperature for 24 h. The reaction solution was poured into water and extracted with dichloromethane. Dry the organic phase with anhydrous magnesium sulfate, filter, spin dry the organic phase, and then separate and purify with silica gel chromatography to obtain an orange-red solid 5,9-bis(5-bromo-thiophene-2-yl)-7-(2- Ethylhexyl)-2,3-di(4-octyloxyphenyl)-7H-pyrrolo[3,4-g]quinoxaline-6,8-dione (0.51g, yield 83%) .

¹ H NMR (300MHz, CDCl ₃ ): δ=7.66(d,4H), δ=7.57(d,2H), δ=7.20(d,2H), δ=6.88(d,4H), δ=3.99( t,4H),δ=3.61(d,2H),δ=1.87(m,1H),δ=1.75(m,4H),δ=1.25-1.31(m,28H),δ=0.86(m,12H ).

¹³ C NMR(151MHz,CDCl ₃ )δ166.44,160.82,152.82,140.24,133.36,132.45,131.90,131.36,129.73,129.02,126.48,118.16,114.45,68.16,42.77,38.08,31.82,30.65,29.36,29.24,29.21 ,28.55,26.04,24.00,23.05,22.67,14.12,14.07,10.49.

Then to prepare 5,9-bis(5-bromo-thiophen-2-yl)-7-(2-ethylhexyl)-2,3-bis(3-octyloxyphenyl)-7H-pyrrolo[ 3,4–g]quinoxaline–6,8–dione as an example. Add 5,9-bis(thiophene-2-yl)-7-(2-ethylhexyl)-2,3-bis(3-octyloxyphenyl)-7H-pyrrolo[3, 4-g] quinoxaline-6,8-dione (0.73g, 0.83mmol), then add 40ml chloroform and 10ml glacial acetic acid and stir well. NBS (N-bromosuccinimide, N-bromosuccinimide) (0.36 g, 2 mmol) was added under ice-bath conditions, and the reaction was carried out at room temperature for 24 h. The reaction solution was poured into water and extracted with dichloromethane. Dry the organic phase with anhydrous magnesium sulfate, filter, spin dry the organic phase, and then separate and purify with silica gel chromatography to obtain an orange-red solid 5,9-bis(5-bromo-thiophene-2-yl)-7-(2- Ethylhexyl)-2,3-bis(3-octyloxyphenyl)-7H-pyrrolo[3,4-g]quinoxaline-6,8-dione (0.7g, yield 81%) .

¹ H NMR (300MHz, CDCl ₃ ): δ=7.63(d,2H), δ=7.54(s,2H), δ=7.18(m,4H), δ=7.08(d,2H), δ=6.91( d,2H),δ=3.98(t,4H),δ=3.63(d,2H),δ=1.77(m,5H),δ=1.20-1.30(m,28H),δ=0.88(m,12H ).

¹³ C NMR(151MHz,CDCl ₃ )δ166.31,159.45,153.06,140.23,138.48,133.66,132.21,131.47,129.17,129.06,126.87,122.79,118.48,117.95,114.84,68.24,42.84,38.11,31.86,30.67,29.41 ,29.36,29.30,28.56,26.17,26.06,24.02,23.04,22.70,14.13,14.07,10.49.

5,9-bis(5-bromo-thiophen-2-yl)-7-R ₁ base-2-R ₂ base-3-R ₃ base-7H-pyrrolo[3,4-g]quinoxaline- 6,8-Diketones are not limited to this.

Example 4

Poly{4,8-bis(2-ethylhexyloxy)-benzo[1,2-b:3,4-b']dithiophene-alternate-5,9-bis(thiophene-2-yl) Synthesis of –7-octyl-2,3-bis(4-octyloxyphenyl)-7H-pyrrolo[3,4-g]quinoxaline-6,8-dione} (abbreviated as P1) .

The synthetic route is as follows:

The monomer 5,9-bis(5-bromo-thiophen-2-yl)-7-octyl-2,3-bis(4-octyloxyphenyl)-7H-pyrrolo[3,4-g ]quinoxaline–6,8–dione (0.104g, 0.1mmol) and 4,8–bis(2–ethylhexyloxy)–2,6-bistrimethyltinbenzo[1,2- b: 3,4-b']dithiophene (0.077g, 0.1mmol) and palladium tetraphenylphosphine (7mg) were added to a 25ml two-necked flask, and then 5ml of toluene and 0.5ml of dimethylformamide (DMF ) to fully dissolve it, and after 20 minutes of debubbling with nitrogen, the temperature was raised to 110° C., and the reaction was carried out for 48 hours. After cooling to room temperature, the reaction solution was dropped into 200 ml of methanol to precipitate a polymer. Put the polymer into a Soxhlet extractor and extract it with methanol, acetone, and n-hexane for 24 hours successively to wash off small molecules and catalysts. Then dissolve the remaining polymer with chloroform, drop it into methanol and re-precipitate. Finally, the polymer was collected with a Buchner funnel to obtain 104 mg of purple-red polymer with a yield of about 79%. The polymer had a number average molecular weight of 27,500 and a weight average molecular weight of 48,400.

Example 5

Poly{4,8-bis(2-ethylhexyloxy)-benzo[1,2-b:3,4-b']dithiophene-alternate-5,9-bis(thiophene-2-yl) Synthesis of –7-octyl-2,3-di(3-octyloxyphenyl)-7H-pyrrolo[3,4-g]quinoxaline-6,8-dione} (abbreviated as P2) .

The synthetic route is as follows:

The monomer 5,9-bis(5-bromo-thiophen-2-yl)-7-octyl-2,3-bis(3-octyloxyphenyl)-7H-pyrrolo[3,4-g ]quinoxaline–6,8–dione (0.104g, 0.1mmol) and 4,8–bis(2–ethylhexyloxy)–2,6-bistrimethyltinbenzo[1,2- b: 3,4-b']dithiophene (0.077g, 0.1mmol) and palladium tetraphenylphosphine (7mg) were added to a 25ml two-necked flask, and then 5ml of toluene and 0.5ml of dimethylformamide (DMF ) to fully dissolve it, and after 20 minutes of debubbling with nitrogen, the temperature was raised to 110° C., and the reaction was carried out for 48 hours. After cooling to room temperature, the reaction solution was dropped into 200 ml of methanol to precipitate a polymer. Put the polymer into a Soxhlet extractor and extract it with methanol, acetone, and n-hexane for 24 hours successively to wash off small molecules and catalysts. Then dissolve the remaining polymer with chloroform, drop it into methanol and re-precipitate it. Finally, use a cloth The polymer was collected by a funnel to obtain 106 mg of a purple polymer, and the yield was about 80%. The polymer had a number average molecular weight of 16,000 and a weight average molecular weight of 30,080.

Example 6

Poly{4,8-bis(2-ethylhexyloxy)-benzo[1,2-b:3,4-b']dithiophene-alternate-5,9-bis(thiophene-2-yl) –7–(2–ethylhexyl)–2,3–bis(4–octyloxyphenyl)–7H–pyrrolo[3,4–g]quinoxaline–6,8–dione} (abbreviated For the synthesis of P3).

The synthetic route is as follows:

The monomer 5,9-bis(5-bromo-thiophen-2-yl)-7-(2-ethylhexyl)-2,3-bis(4-octyloxyphenyl)-7H-pyrrolo[ 3,4–g]quinoxaline–6,8–dione (0.104 g, 0.1 mmol) and 4,8–bis(2–ethylhexyloxy)–2,6-dimethyltinbenzo [1,2-b:3,4-b']dithiophene (0.077g, 0.1mmol) and palladium tetraphenylphosphine (7mg) were added to a 25ml two-necked flask, then 5ml of toluene and 0.5ml of dimethyl Dimethyl formamide (DMF) was used to fully dissolve it, and after 20 minutes of nitrogen degassing, the temperature was raised to 110° C., and the reaction was carried out for 48 hours. After cooling to room temperature, the reaction solution was dropped into 200 ml of methanol to precipitate a polymer. Put the polymer into a Soxhlet extractor and extract it with methanol, acetone, and n-hexane for 24 hours successively to wash off small molecules and catalysts. Then dissolve the remaining polymer with chloroform, drop it into methanol and re-precipitate it. Finally, use a cloth The polymer was collected by a funnel to obtain 108 mg of a purple polymer, and the yield was about 82%. The polymer had a number average molecular weight of 12400 and a weight average molecular weight of 24800.

Example 7

Poly{4,8-bis(2-ethylhexyloxy)-benzo[1,2-b:3,4-b']dithiophene-alternate-5,9-bis(thiophene-2-yl) –7–(2–ethylhexyl)–2,3–bis(3–octyloxyphenyl)–7H–pyrrolo[3,4–g]quinoxaline–6,8–dione} (abbreviated For the synthesis of P4).

The synthetic route is as follows:

The monomer 5,9-bis(5-bromo-thiophen-2-yl)-7-(2-ethylhexyl)-2,3-bis(3-octyloxyphenyl)-7H-pyrrolo[ 3,4–g]quinoxaline–6,8–dione (0.104 g, 0.1 mmol) and 4,8–bis(2–ethylhexyloxy)–2,6-dimethyltinbenzo [1,2-b:3,4-b']dithiophene (0.077g, 0.1mmol) and palladium tetraphenylphosphine (7mg) were added to a 25ml two-necked flask, then 5ml of toluene and 0.5ml of dimethyl Dimethyl formamide (DMF) was used to fully dissolve it, and after 20 minutes of nitrogen degassing, the temperature was raised to 110° C., and the reaction was carried out for 48 hours. After cooling to room temperature, the reaction solution was dropped into 200 ml of methanol to precipitate a polymer. Put the polymer into a Soxhlet extractor and extract it with methanol, acetone, and n-hexane for 24 hours successively to wash off small molecules and catalysts. Then dissolve the remaining polymer with chloroform, drop it into methanol and re-precipitate it. Finally, use a cloth The polymer was collected by a funnel to obtain 107 mg of a purple-red polymer, and the yield was about 81%. The polymer had a number average molecular weight of 15300 and a weight average molecular weight of 34272.

Example 8

Poly{4,8-bis(4,5-didecylthiophen-2-yl)-benzo[1,2-b:3,4-b']dithiophene-alternating-5,9-bis(thiophene –2-yl)-7-octyl-2,3-bis(4-octyloxyphenyl)-7H-pyrrolo[3,4-g]quinoxaline-6,8-dione} (abbreviated for the synthesis of P5).

The synthetic route is as follows:

The monomer 5,9-bis(5-bromo-thiophen-2-yl)-7-octyl-2,3-bis(4-octyloxyphenyl)-7H-pyrrolo[3,4-g ]quinoxaline-6,8-dione (0.208g, 0.2mmol) and 4,8-di(4,5-didecylthiophen-2-yl)-2,6-ditrimethyltinbenzo [1,2-b:3,4-b']dithiophene (0.248g, 0.2mmol) and palladium tetraphenylphosphine (8mg) were added to a 25ml two-necked flask, and then 5ml of toluene and 0.5ml of dimethyl Dimethyl formamide (DMF) was used to fully dissolve it, and after 20 minutes of nitrogen degassing, the temperature was raised to 110° C., and the reaction was carried out for 48 hours. After cooling to room temperature, the reaction solution was dropped into 200 ml of methanol to precipitate a polymer. Put the polymer into a Soxhlet extractor and extract it with methanol, acetone, and n-hexane for 24 hours successively to wash off small molecules and catalysts. Then dissolve the remaining polymer with chloroform, drop it into methanol and re-precipitate it. Finally, use a cloth The polymer was collected by a funnel to obtain 303 mg of a purple polymer, and the yield was about 84%. The polymer had a number average molecular weight of 45320 and a weight average molecular weight of 71714.

Example 9

Poly{4,8-bis(4,5-didecylthiophen-2-yl)-benzo[1,2-b:3,4-b']dithiophene-alternating-5,9-bis(thiophene –2-yl)-7-(2-ethylhexyl)-2,3-di(4-octyloxyphenyl)-7H-pyrrolo[3,4-g]quinoxaline-6,8- Diketone} (abbreviated as P6) synthesis.

The synthetic route is as follows:

The monomer 5,9-bis(5-bromo-thiophen-2-yl)-7-(2-ethylhexyl)-2,3-bis(4-octyloxyphenyl)-7H-pyrrolo[ 3,4–g]quinoxaline–6,8–dione (0.208g, 0.2mmol) and 4,8–bis(4,5-didecylthiophen-2-yl)–2,6-bistris Methyltinbenzo[1,2-b:3,4-b']dithiophene (0.248g, 0.2mmol) and palladium tetraphenylphosphine (8mg) were added to a 25ml two-necked bottle, and then 5ml of toluene was added and 0.5ml of dimethylformamide (DMF) to fully dissolve it, and after 20 minutes of nitrogen evacuation, the temperature was raised to 110° C., and the reaction was carried out for 48 hours. After cooling to room temperature, the reaction solution was dropped into 200 ml of methanol to precipitate a polymer. Put the polymer into a Soxhlet extractor and extract it with methanol, acetone, and n-hexane for 24 hours successively to wash off small molecules and catalysts. Then dissolve the remaining polymer with chloroform, drop it into methanol and re-precipitate it. Finally, use a cloth The polymer was collected by a funnel to obtain 320 mg of a purple polymer, and the yield was about 89%. The polymer had a number average molecular weight of 62,026 and a weight average molecular weight of 89,517.

Example 10

Poly{4,8-bis(4,5-didecylthiophen-2-yl)-benzo[1,2-b:3,4-b']dithiophene-alternating-5,9-bis(thiophene –2-yl)-7-(2-ethylhexyl)-2,3-di(3-octyloxyphenyl)-7H-pyrrolo[3,4-g]quinoxaline-6,8- Synthesis of diketone} (abbreviated as P7).

The synthetic route is as follows:

The monomer 5,9-bis(5-bromo-thiophen-2-yl)-7-(2-ethylhexyl)-2,3-bis(3-octyloxyphenyl)-7H-pyrrolo[ 3,4–g]quinoxaline–6,8–dione (0.208g, 0.2mmol) and 4,8–bis(4,5-didecylthiophen-2-yl)–2,6-bistris Methyltinbenzo[1,2-b:3,4-b']dithiophene (0.248g, 0.2mmol) and palladium tetraphenylphosphine (8mg) were added to a 25ml two-necked bottle, and then 5ml of toluene was added and 0.5ml of dimethylformamide (DMF) to fully dissolve it, and after 20 minutes of nitrogen evacuation, the temperature was raised to 110° C., and the reaction was carried out for 48 hours. After cooling to room temperature, the reaction solution was dropped into 200 ml of methanol to precipitate a polymer. Put the polymer into a Soxhlet extractor and extract it with methanol, acetone, and n-hexane for 24 hours successively to wash off small molecules and catalysts. Then dissolve the remaining polymer with chloroform, drop it into methanol and re-precipitate it. Finally, use a cloth The polymer was collected by a funnel to obtain 290 mg of a purple polymer, and the yield was about 81%. The polymer had a number average molecular weight of 24,071 and a weight average molecular weight of 44,994.

Example 11

Preparation and performance of polymer solar cell devices

The polymer solar cell device adopts a flip-chip structure, and the ITO glass substrate is used as the electron collection electrode. The ITO glass is washed with acetone, detergent, deionized water and isopropanol in sequence, and then placed in an oven at 80°C for overnight drying. Then, 0.5mg/ml cross-linkable PF ₃ N-OX solution dissolved in methanol and acetic acid mixed solvent (100:1v:v) was spin-coated at 2000rpm in a nitrogen-protected glove box before drying. On the cooled ITO substrate, heat at 140° C. for 25 minutes to carry out cross-linking reaction, and finally obtain a 5 nm-thick cross-linked PF ₃ N-OX film. Then, a solution of one of the polymers synthesized in the above examples and PCBM in different ratios (the solvent is o-dichlorobenzene) was spin-coated on the PF ₃ N-OX film to obtain an active layer of about 80-90 nm. Then 10nm MoO ₃ is thermally deposited on the active layer at a rate of 0.01nm/s in a plating chamber with a vacuum degree of 3×10 ^-4 Pa, and then the above-mentioned device is placed on a custom-made mask plate, and then thermally deposited to obtain The effective area is 0.16cm ² and the thickness is 80nm. Metal Al serves as a hole-collecting electrode. Finally, the device is covered with epoxy resin to cover the effective device area, and cured in a UV curing oven for 5 minutes to encapsulate the device to isolate the influence of water and oxygen on the device.

Power conversion efficiency (PCE) is measured under AM 1.5G XES-40S1150W AAA Class Solar Simulator (sun simulation lamp model). The light intensity of the solar simulation lamp is calibrated to 100mWcm ^-2 by a standard silicon solar cell. The current density-voltage (JV) curve of the battery device is recorded and measured by Keithley2400 Source Measure Unit. Among them, the cell efficiencies of devices based on P1, P2, P3, and P4 are shown in Table 1, and the corresponding JV curves are shown in Figure 3.

The above-mentioned embodiment is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited by the above-mentioned embodiment, and any other changes, modifications, substitutions, combinations, Simplifications should be equivalent replacement methods, and all are included in the protection scope of the present invention.

Table 1

Claims (4)

1. 7H-pyrrolo- [3,4-g] quinoxaline-6, the conjugated polymer of 8-diketone are contained, it is characterised in that structural formula is：

Wherein, R₁、R₂And R₃For hydrogen atom or alkyl chain；The alkyl chain be the straight chain with 1～24 carbon atom, side chain or Person's cyclic alkyl chain, or wherein one or more carbon atoms, by oxygen atom replacement, hydrogen atom is by halogen atom, thiazolinyl, alkynyl, virtue Base, hydroxyl, amino, carbonyl, carboxyl, ester group, cyano group or nitro replace；Ar is aromatic group；The n is 1～10000 nature Number, 0 ＜ x ＜, 1,0 ＜ y ＜ 1, x+y=1.

2. conjugated polymer according to claim 1, it is characterised in that the aromatic group Ar is as follows structure One or more：

Wherein, R, R_a～R_dReplaced by oxygen atom for hydrogen atom or alkyl chain, or wherein one or more carbon atoms, hydrogen atom Replaced by halogen atom, thiazolinyl, alkynyl, aryl, hydroxyl, amino, carbonyl, carboxyl, ester group, cyano group or nitro.

3. conjugated polymer according to claim 1 and 2, it is characterised in that described R, R_a～R_dIt is with 1～24 carbon The straight chain of atom, side chain or cyclic alkyl chain.

4. the conjugated polymer described in claim 1 or 2 or 3 is preparing the luminescent layer of polymer LED device, is preparing Semiconductor active layer in polymer field effect transistor or the application in preparing the active layer of polymer solar photovoltaic cell.