Fluorene vinyl diketopyrrolopyrrole compound and preparation method thereof

Abstract

The invention relates to a fluorene vinyl diketopyrrolopyrrole compound which has a structure shown in a general formula (I), and in the general formula (I), R represents C1-C12 alkyl groups or C1-C6 alkoxy groups, C6-C12 aryl groups and C1-C6 alkyl groups which are optionally substituted by halogen. The invention also relates to a process for the preparation of compounds of general formula (I). The preparation method disclosed by the invention is simple, efficient and mild in condition; and the fluorene vinyl diketopyrrolopyrrole compound disclosed by the invention has a huge application prospect in the field of organic semiconductors. # imgabs0 #

Description

Technical Field

[0001] The invention belongs to the technical field of organic chemical synthesis, and specifically relates to a fluorene vinyl pyrrolopyrrole dione compound and a preparation method thereof. Background Art

[0002] Due to the low cost, light weight, and easily tunable optoelectronic properties of organic semiconductor materials, as well as their abundant material sources, solution processing, and good compatibility with plastic substrates, their research and development is of great strategic significance for promoting the development of information, energy, medical care, national defense and other fields.

[0003] Diketopyrrolopyrrole (DPP) materials are a type of organic semiconductor material that is currently widely used. This type of material has the characteristics of good photothermal stability, low band gap, wide absorption spectrum range and high fluorescence quantum yield, and can be widely used in organic field effect transistors, organic solar cells, organic light-emitting diodes and biological fluorescence probes.

[0004] Therefore, people have been looking forward to obtaining new pyrrolopyrrole diketo compounds through simple and efficient synthetic methods. Summary of the invention

[0005] In view of this, in a first aspect, the present invention provides a fluorene vinyl pyrrolopyrrole dione compound having a structure of general formula (I):

[0006]

[0007] wherein R represents optionally substituted alkyl, cycloalkyl, cycloalkylalkyl, aryl or alkoxyarylalkyl;

[0008] Preferably, R represents C1-C 12 Alkyl, C3-C 12 Cycloalkyl, C6-C 12 Aryl or C1-C6 alkoxy C6-C 12 Aryl C1-C6 alkyl; optionally, the above substituents may be further substituted by substituents selected from the group consisting of cyano, halogen, hydroxy, nitro, C1-C6 alkyl, C1-C6 alkoxy, C1-C6 alkylthio and C6-C 12 Aryl;

[0009] Further preferably, R represents a C1-C 12 Alkyl or C1-C6 alkoxy C6-C 12 Aryl C1-C6 alkyl;

[0010] More preferably, R represents C1-C 12 Alkyl or C1-C6 alkoxy C6-C 12Aryl C1-C6alkyl, such as C1-C6alkyl (eg n-butyl or 2-ethylhexyl), octyl or methoxyphenylmethyl.

[0011] In a second aspect, the present invention also provides a method for preparing a fluorene vinyl pyrrolopyrrole diketo compound of general formula (I), comprising the following steps:

[0012] (1) at a temperature of 30-80°C and in the presence of piperidine, a compound of formula (a)

[0013]

[0014] Where R is as defined above,

[0015] reacting with 2-biphenylcarboxaldehyde in a first solvent to obtain a compound of formula (b);

[0016]

[0017] wherein the first solvent is acetonitrile;

[0018] wherein Ar represents 2-biphenyl;

[0019] (2) reacting the compound of formula (b) with an oxidizing agent in a second solvent at a temperature of 5-80° C. to obtain a compound of general formula (I),

[0020] wherein the oxidizing agent is selected from at least one of ferric chloride, [bis(trifluoroacetoxy)iodo]benzene (PIFA) and 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ);

[0021] The second solvent is selected from the group consisting of dichloromethane, chloroform, carbon tetrachloride, tetrachloroethane, nitromethane, chlorobenzene, tetrahydrofuran, dioxane and mixtures thereof, preferably dichloromethane, nitromethane or mixtures thereof.

[0022] In a third aspect, the present invention relates to the use of the compound of general formula (I) as an organic semiconductor material.

[0023] The beneficial effect of the present invention is that the fluorene vinyl pyrrolopyrrole dione compound of the general formula (I) of the present invention can be used as an organic semiconductor material and can be synthesized in a simple, efficient and mild manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The hydrogen spectrum of the DPP compound C4-Flu of the present invention prepared in Example 1;

[0025] Figure 2 The hydrogen spectrum of the DPP compound C26-Flu of the present invention prepared in Example 2;

[0026] Figure 3 The mass spectrum of the DPP compound C4-Flu of the present invention prepared in Example 1;

[0027] Figure 4 This is the mass spectrum of the DPP compound C26-Flu of the present invention prepared in Example 2. DETAILED DESCRIPTION

[0028] In the present invention, unless otherwise stated, all operations are carried out at room temperature (25° C.) and normal pressure (101 KPa).

[0029] The inventors have found in their research that the fluorene vinyl pyrrolopyrrole diketo compound of the general formula (I) of the present invention can be obtained in a relatively high yield by using a specific oxidizing agent. The prepared fluorene vinyl pyrrolopyrrole diketo compound of the general formula (I) can be used as an organic semiconductor material.

[0030] Therefore, in a first aspect, the present invention provides a fluorene vinyl pyrrolopyrrole dione compound having a structure of general formula (I):

[0031]

[0032] wherein R represents optionally substituted alkyl, cycloalkyl, cycloalkylalkyl, aryl or alkoxyarylalkyl;

[0033] Preferably, R represents C1-C 12 Alkyl, C3-C 12 Cycloalkyl, C6-C 12 Aryl or C1-C6 alkoxy C6-C 12 Aryl C1-C6 alkyl; optionally, the above substituents may be further substituted by substituents selected from the group consisting of cyano, halogen, hydroxy, nitro, C1-C6 alkyl, C1-C6 alkoxy, C1-C6 alkylthio and C6-C 12 Aryl;

[0034] Further preferably, R represents a C1-C 12 Alkyl or C1-C6 alkoxy C6-C 12 Aryl C1-C6 alkyl;

[0035] More preferably, R represents C1-C 12 Alkyl or C1-C6 alkoxy C6-C 12 Aryl C1-C6alkyl, such as C1-C6alkyl (eg n-butyl or 2-ethylhexyl), octyl or methoxyphenylmethyl.

[0036] The various embodiments described herein can be combined with each other. Combinations that violate the laws of nature and combinations that are excluded by a person skilled in the art based on his / her expertise are not included.

[0037] In a second aspect, the present invention also provides a method for preparing a fluorene vinyl pyrrolopyrrole diketo compound of general formula (I), comprising the following steps:

[0038] (1) at a temperature of 30-80°C and in the presence of piperidine, a compound of formula (a)

[0039]

[0040] Where R is as defined above,

[0041] reacting with 2-biphenylcarboxaldehyde in a first solvent to obtain a compound of formula (b);

[0042]

[0043] wherein the first solvent is acetonitrile;

[0044] wherein Ar represents 2-biphenyl;

[0045] (2) reacting the compound of formula (b) with an oxidizing agent in a second solvent at a temperature of 5-80° C. to obtain a compound of general formula (I),

[0046] wherein the oxidizing agent is selected from at least one of ferric chloride, [bis(trifluoroacetoxy)iodo]benzene (PIFA) and 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ);

[0047] The second solvent is selected from the group consisting of dichloromethane, chloroform, carbon tetrachloride, tetrachloroethane, nitromethane, chlorobenzene, tetrahydrofuran, dioxane and mixtures thereof, preferably dichloromethane, nitromethane or mixtures thereof.

[0048] Preferably, in step (1), the amount of 2-biphenylcarboxaldehyde used in the present invention is 2-3 equivalents, preferably 2-2.5 equivalents, most preferably 2.2-2.5 equivalents, based on the amount of the compound of formula (a).

[0049] Preferably, in step (1), the amount of piperidine used is 2-3 equivalents, preferably 2-2.5 equivalents, most preferably 2.2-2.5 equivalents, based on the amount of the compound of formula (a).

[0050] Preferably, in steps (1) and (2), the reaction is carried out under an inert atmosphere, and the inert gas used may be nitrogen, argon or helium or a mixture thereof.

[0051] Preferably, in step (2), the amount of the oxidizing agent of the present invention used is 1-10 equivalents, preferably 2-8 equivalents, most preferably 2.5-6 equivalents, and further preferably 3-5 equivalents, based on the amount of the compound of formula (b).

[0052] Preferably, the oxidizing agent can be selected from at least one of ferric chloride, [bis(trifluoroacetoxy)iodo]benzene (PIFA) and 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ), preferably ferric chloride; optionally, the oxidizing agent is used in the form of a solution. The inventor unexpectedly found that the compound of general formula (I) can be well prepared and obtained by using the oxidizing agent of the type defined in the present invention, while other oxidizing agents including inorganic oxidizing agents such as potassium permanganate, hydrogen peroxide and chromium trioxide, and organic oxidizing agents such as trifluoroacetic acid, azobisisobutyronitrile and dibenzoyl peroxide are difficult to obtain or difficult to obtain the compound of general formula (I) of the present invention with a higher yield. Therefore, for the technical solution of the present invention, the oxidizing agent used in the present invention is a specific oxidizing agent.

[0053] In a preferred embodiment of the present invention, the oxidizing agent is added dropwise to the solution of the compound of formula (b) in the form of a solution, wherein the content of the oxidizing agent in the oxidizing agent solution may be (0.1-1.0 mmol) / mL solvent, preferably (0.15-0.8 mmol) / mL solvent, more preferably (0.2-0.5 mmol) / mL solvent, and the solvent used here is the above-mentioned second solvent, preferably nitromethane; the content of the compound of formula (b) in the solution of the compound of formula (b) may be (0.001-0.5 mmol) / mL solvent, preferably (0.01-0.2 mmol) / mL solvent, more preferably (0.015-0.1 mmol) / mL solvent, and the solvent used here is the above-mentioned second solvent, preferably dichloromethane. It should be understood here that the above content refers to the content before the two reactants are mixed; the oxidizing agent solution and the solution of the compound of formula (b) may use the same or different solvents.

[0054] Preferably, in the method of the present invention, in step (1), the reaction temperature may be 35-80° C., preferably 40-65° C., more preferably 45-60° C.; in step (2), the reaction temperature may be 8-60° C., preferably 10-50° C., more preferably 12-45° C. Here, it should be understood that when the boiling point of the solvent used at normal temperature and pressure is lower than the maximum value of the above reaction temperature range, the upper limit of the reaction temperature is the boiling point of the solvent used, which is well known to those skilled in the art.

[0055] Preferably, in the method of the present invention, in step (1), the reaction time may be 6-24 hours, preferably 8-18 hours, more preferably 10-15 hours; in step (2), the reaction time may be 4-24 hours, preferably 5-18 hours, more preferably 8-15 hours. The reaction progress of the present invention can be monitored by thin layer chromatography.

[0056] After the reaction of the present invention is completed, separation can be carried out by conventional separation methods, such as column chromatography. The appropriate eluent can be determined by experiment. Preferably, n-hexane and dichloromethane are used for gradient elution in step (1), and n-hexane, dichloromethane and ethyl acetate are used for gradient elution in step (2).

[0057] In the present invention, the compound of formula (a) is a diketopyrrolopyrrole compound, and its preparation method is known. For example, it can be synthesized by referring to the method described in Chem. Mater. 2024, 36, 4215-4225, or it can be directly purchased.

[0058] By using the method of the present invention, the fluorene vinyl pyrrolopyrrole dione compound of the general formula (I) of the present invention can be obtained in a simple, efficient and mild manner.

[0059] In a third aspect, the present invention also relates to the use of the fluorene vinyl pyrrolopyrrole dione compound of the general formula (I) as an organic semiconductor material.

[0060] In the present invention, the term "organic semiconductor material" refers to an organic material having semiconductor properties. The application of diketopyrrolopyrrole compounds in the field of organic semiconductors is well known to those skilled in the art and will not be described in detail herein.

[0061] Hereinafter, the present invention will be described in more detail with reference to the following examples. These embodiments disclosed below are for illustrative purposes only and are not intended to limit the present invention. Those skilled in the art may make various modifications, additions and substitutions to the embodiments of the present invention without departing from the scope and spirit of the present invention.

[0062] 1. Preparation Example

[0063] Example 1

[0064] Step (1)

[0065] Under nitrogen atmosphere, a mixture of compound C4-DPP (138.2 mg, 0.5 mmol), 2-biphenylcarboxaldehyde (1.1 mmol) and piperidine (1 mmol) was dissolved in 4 mL of acetonitrile and stirred at 55 ° C for 13 hours. The progress of the reaction was monitored by thin layer chromatography (TLC). After completion, the reaction mixture was diluted with 15 mL of dichloromethane and washed with 15 mL of water. The organic phase was separated, dried with Na2SO4, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography (gradient elution: from n-hexane to dichloromethane) to obtain C4-2DP-DPP with a yield of 82%.

[0066]

[0067] 1 H NMR (400MHz, CDCl3, 298K) δ = 8.68 (d, J = 16.0Hz, 2H), 7.68 (dd, J = 5.5, 3.7Hz, 2H), 7.50 -7.29(m,16H),6.42(d,J=16.0Hz,2H),3.45(t,J=7.3Hz,4H),1.37(dt,J=14.5,7.2Hz,4H),1.24(dq,J=14.4,7.2Hz,4H),0.90(t,J=7.2Hz,6H);

[0068] MS(MALDI-TOF)m / z calcd(%)for C 42 H 40 N2O2:604.192, found [M+H] + :605.255.

[0069] Step (2)

[0070] C4-2DP-DPP (604.3 mg, 1 mmol) and dichloromethane (50 mL) were added to a 100 mL round-bottom flask, and then 4 eq FeCl (dissolved in 20 mL nitromethane) was added dropwise and the reaction mixture was stirred at room temperature for 12 hours. The progress of the reaction was monitored by thin layer chromatography (TLC). The reactants were washed with 200 mL of water. The organic phase was separated, dried with Na2SO4, filtered, and concentrated under reduced pressure. After cooling to room temperature, the product was washed with water, dried, and concentrated. The crude product was purified by column chromatography on silica gel (gradient elution: from n-hexane, dichloromethane to ethyl acetate) to obtain C4-Flu (yield 53%).

[0071]

[0072] 1H NMR (400MHz, CDCl3, 298K): δ = 7.78 -7.61(m,8H),7.40(tt,J=7.4,1.3Hz,4H),7.30(td,J=7.5,1.1Hz,2H),7.25-7.19(m,2H),7.14 (s,2H),3.73(t,J=7.2Hz,4H),1.62(p,J=7.3Hz,4H),1.38-1.27(m,4H),0.87(t,J=7.3Hz,6H);

[0073] MS(MALDI-TOF)m / z calcd(%)for C 42 H 36 N2O2:600.180,found[M+H]+:601.214,[M+Na] + :623.197.

[0074] Example 2

[0075] Step (1)

[0076] Under nitrogen atmosphere, a mixture of compound C26-DPP (194.3 mg, 0.5 mmol), 2-biphenylcarboxaldehyde (1.1 mmol) and piperidine (1 mmol) was dissolved in 4 mL of acetonitrile and stirred at 55 ° C for 13 hours. The progress of the reaction was monitored by thin layer chromatography (TLC). After completion, the reaction mixture was diluted with 15 mL of dichloromethane and washed with 15 mL of water. The organic phase was separated, dried with Na2SO4, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography (gradient elution: from n-hexane to dichloromethane) to obtain C26-2DP-DPP with a yield of 86%.

[0077]

[0078] 1 H NMR (400MHz, CDCl3, 298K) δ = 8.72 (d, J = 15.9Hz, 2H), 7.71-7.64 (m, 2H), 7.51-7.27 (m, 16H), 6. 53(d,J=15.9Hz,2H),3.47-3.33(m,4H),1.50(s,2H),1.24(q,J=10.8,7.0Hz,16H),0.88(dt,J=

[0079] 15.0,7.1Hz,12H);

[0080] MS(MALDI-TOF)m / z calcd(%)for C 50 H 56N2O2:716.326, found [M+H] + :717.325.

[0081] Step (2)

[0082] C26-2DP-DPP (716.3 mg, 1 mmol) and dichloromethane (50 mL) were added to a 100 mL round-bottom flask, and then 4 eq FeCl (dissolved in 20 mL nitromethane) was added dropwise and the reaction mixture was stirred at room temperature for 12 hours. The progress of the reaction was monitored by thin layer chromatography (TLC). The reactants were washed with 200 mL of water. The organic phase was separated, dried with Na2SO4, filtered, and concentrated under reduced pressure. After cooling to room temperature, the product was washed with water, dried, and concentrated. The crude product was purified by column chromatography on silica gel (gradient elution: from n-hexane, dichloromethane to ethyl acetate) to obtain C26-Flu (yield 55%).

[0083]

[0084] 1 H NMR (400MHz, CDCl3, 298K): δ=7.78-7.61(m,8H),7.40(tt,J=7.4,1.3Hz,4H),7.30(td,J=7.5,1.1Hz,2H),7.25– 7.19(m,2H),7.14(s,2H),3.73(t,J=7.2Hz,4H),1.62(p,J=7.3Hz,4H),1.38–1.27(m,4H),0.87(t,J=7.3Hz,6H);

[0085] MS(MALDI-TOF)m / z calcd(%)for C 50 H 54 N2O2:712.281,found[M+H]+:713.296,[M+Na] + :735.283.

[0086] Comparative Example 1

[0087] The steps of Example 1 were repeated, except that the oxidizing agent was trifluoroacetic acid, and the yield was less than 5%.

[0088] Comparative Example 2

[0089] The steps of Example 1 were repeated, except that the oxidizing agent was potassium permanganate, and no reaction product was detected after the reaction.

Claims

1. A fluorene vinyl pyrrolopyrrole dione compound having the structure of general formula (I): R represents a C1-C 12 Alkyl or C1-C6 alkoxy C6-C 12 Aryl C1-C6 alkyl.

2. The compound according to claim 1, wherein R stands for C1-C 12 The alkyl group is preferably n-butyl or 2-ethylhexyl.

3. A method for preparing the compound according to claim 1 or 2, comprising the following steps: (1) at a temperature of 30-80°C and in the presence of piperidine, a compound of formula (a) wherein R is as defined in claim 1 or 2, reacting with 2-biphenylcarboxaldehyde in a first solvent to obtain a compound of formula (b); wherein the first solvent is acetonitrile; wherein Ar represents 2-biphenyl; (2) reacting the compound of formula (b) with an oxidizing agent in a second solvent at a temperature of 5-80° C. to obtain a compound of general formula (I), wherein the oxidizing agent is selected from at least one of ferric chloride, [bis(trifluoroacetoxy)iodo]benzene (PIFA) and 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ); The second solvent is selected from the group consisting of dichloromethane, chloroform, carbon tetrachloride, tetrachloroethane, nitromethane, chlorobenzene, tetrahydrofuran, dioxane and mixtures thereof, preferably dichloromethane, nitromethane or mixtures thereof.

4. The method according to claim 3, wherein in step (2), the amount of the oxidizing agent used is 1-10 equivalents, preferably 2-8 equivalents, most preferably 4-6 equivalents, based on the amount of the compound of formula (b).

5. The method according to claim 3 or 4, wherein in step (2), the reaction temperature is 10-50°C, more preferably 12-45°C.

6. The method according to claim 3 or 4, wherein in step (2), the reaction time is 6-24 hours, preferably 8-18 hours, more preferably 10-15 hours.

Images