Compounds, compositions, films, photoelectric conversion elements, and CMOS image sensors

Abstract

The present invention provides an ADA-type non-fullerene acceptor material having a deep HOMO level while extending the π-conjugated system, as well as a composition, film, photoelectric conversion element, and CMOS image sensor using this compound. [Solution] The compound of the present invention is represented by the following general formula (1). ADA ···(1) Each A is independently a group represented by any of (2a) to (2d) below, at least one of the two A's contains (2a) or (2b) below, and D is an electron-donating group consisting of 2 to 20 cyclic groups. [C1] TIFF2026116245000059.tif37170

Description

[Technical Field]

[0001] The present invention relates to compounds, compositions, films, photoelectric conversion elements, and CMOS image sensors suitable as semiconductor materials used in photoelectric conversion elements. [Background technology]

[0002] CMOS image sensors, which are equipped with photoelectric conversion elements, are used, for example, as image sensors in digital cameras and smartphones. CMOS image sensors include inorganic CMOS image sensors and organic CMOS image sensors, with inorganic CMOS image sensors using silicon photodiodes being the most commonly used. On the other hand, organic CMOS image sensors, by utilizing the high light absorption capacity of organic thin films, can achieve both high resolution and a wide dynamic range, as well as the incorporation of a global shutter that minimizes image distortion. Thus, organic CMOS image sensors are considered to be able to solve the problem of achieving both a high dynamic range and a global shutter, which is difficult for inorganic CMOS image sensors, and therefore there is a demand for materials suitable for organic CMOS image sensors.

[0003] Furthermore, in photoelectric conversion elements (hereinafter also referred to as "inorganic photoelectric conversion elements") used in inorganic CMOS image sensors, inexpensive silicon semiconductors are generally used for photoresponses up to an absorption wavelength of 1000 nm, but very expensive indium gallium arsenide (InGaAs) semiconductors are used when the absorption wavelength exceeds 1000 nm. Therefore, there is a demand for semiconductor materials that are inexpensive and can be used in the long-wavelength region, and organic semiconductor materials (hereinafter also referred to as "organic semiconductor materials") are attracting attention as candidates for such materials.

[0004] In photoelectric conversion elements (hereinafter also referred to as "organic photoelectric conversion elements") incorporated into organic CMOS image sensors, the photoelectric conversion capability and absorption wavelength range can be controlled by the molecular design of the p-type and n-type semiconductor materials used in the organic thin film (photoelectric conversion layer) that constitutes the photoelectric conversion element. In recent years, high photoelectric conversion capability has been reported in elements using non-fullerene acceptors as n-type semiconductor materials. In photoelectric conversion elements using non-fullerene acceptors, the role of controlling the absorption wavelength range is mainly played by the n-type semiconductor material. As n-type semiconductor materials (light-absorbing and electron-transporting materials), compounds having an electron acceptor (A) part and an electron donor (D) part, so-called ADA-type compounds (hereinafter also referred to as "ADA-type non-fullerene acceptor materials"), are known. The absorption wavelength of ADA-type compounds can be designed by reducing the HOMO-LUMO gap by selecting the electron-withdrawing properties of part A and the electron-donating properties of part D.

[0005] ADA-type compounds include a cyclopentadithiophene central donor (D) moiety and a thiophene ring (D) substituted with a specific substituent. 1 ), (D 2 ) with section D sandwiched between, AD 1 -DD 2 -A type compounds are known. For example, Non-Patent Literature 1 discloses a compound represented by the following formula (a) which is an A-D'-D-D'-A type compound, a compound represented by the following formula (b) which is an A-D'-DD”-A type compound, and a compound represented by the following formula (c) which is an AD”-DD”-A type compound. Here, D' represents a thiophene ring substituted with an alkoxy group, and D” represents a thiophene ring substituted with an alkyl group. According to Non-Patent Literature 1, the compound represented by the following formula (a) is said to achieve the longest absorption wavelength. The compound represented by the following formula (a) is a compound in which the alkyl group bonded to the thiophene ring in the D” portion of the compound represented by the following formula (b) or the following formula (c) is replaced with an alkoxy group, which is a strong electron-donating group, to form the D' portion.

[0006] [ka] [Prior art documents] [Non-patent literature]

[0007] [Non-Patent Document 1] Jaewon Lee, et al., “ACS Energy Lett.”, 2019, Vol. 4, pp. 1401-1409. [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] Incidentally, in ADA-type non-fullerene acceptor materials, molecular design that extends the π-conjugated system of the molecules is known to lengthen the absorption wavelength. However, when the π-conjugated system of molecules is extended, the band gap becomes extremely small, causing the HOMO level to rise despite it being an n-type semiconductor material, approaching the HOMO level of a p-type semiconductor material. This approach to the HOMO level creates a problem in photodiode devices driven by reverse bias, making hole extraction difficult and reducing the external quantum efficiency (EQE). One way to solve this problem is to raise the HOMO level of the p-type semiconductor material or the hole transport material of the adjacent layer, but this leads to material instability due to oxidation by oxygen, etc., causing difficulties in synthesis, instability of the coating ink, and a decrease in the reliability of the device. Therefore, in the development of n-type semiconductor materials, there was a need for new molecular design guidelines that could achieve deep HOMO levels while extending the π-conjugated system, which is a trade-off relationship.

[0009] The present invention aims to provide a compound having a deep HOMO level while extending the π-conjugated system in an ADA-type non-fullerene acceptor material, as well as a composition, film, photoelectric conversion element, and CMOS image sensor using this compound. [Means for solving the problem]

[0010] In view of the above problems, the present inventors have studied compounds having a deep HOMO level and capable of shifting the absorption wavelength to a longer wavelength. Specifically, in the A part and the linking part of the A-D-A type compound, substituents and π-conjugated system expansion were studied. As a result, among the A parts connected by a diene structure with an expanded π-conjugated system, it has been found that in a material having a cyano group and / or a nitrogen-containing aromatic six-membered ring in the A part, it is possible to design a material having a deep HOMO level while shifting the absorption wavelength to a longer wavelength, and the present invention has been completed.

[0011] The present invention includes the following embodiments, but is not limited thereto. [1] A compound represented by the following general formula (1). A-D-A ···(1) In the general formula (1), each A is independently a group represented by any one of the following general formulas (2a) to (2d), and at least one of the two As contains the following general formula (2a) or (2b), and D is an electron-donating group composed of 2 to 20 rings.

[0012] [Chemical formula]

[0013] In the general formulas (2a) to (2d), V 1 ~V 4 are each independently C-R 1 or a nitrogen atom, R 1 is a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom or a cyano group, provided that when V 1 ~V 4 is C-R 1 , at least one of R 1 is a cyano group. Z is an oxygen atom or a dicyanomethylene group, and Ar 1 is a substituted or unsubstituted aryl group or heteroaryl group.

[0014] [2] The compound according to [1], wherein the two As in the general formula (1) are the same and are selected from the general formula (2a) or (2b). [3] The compound of [1] wherein the two A's in general formula (1) are different, and the combination of the two A's is the combination of general formulas (2a) and (2c), or the combination of general formulas (2b) and (2d).

[0015] [4] Any of the compounds from [1] to [3] above, wherein A in the general formula (1) is the following general formula (2a') or (2c').

[0016] [ka]

[0017] [5] Any of the compounds from [1] to [3] above, wherein A in the general formula (1) is the following general formula (2b') or (2d').

[0018] [ka]

[0019] In general formulas (2b') and (2d'), R 2 Each of these is independently a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, or a cyano group.

[0020] [6] Any of the compounds [1] to [5] above, wherein D in the general formula (1) is a group represented by any of the following general formulas (3) to (5).

[0021] [ka]

[0022] In general formulas (3) to (5), W is C - (R 3 )2, Si-(R 3 )2, Ge-(R 3 )2, NR 3 , OC(R 3 )2, or C(R 3 )2-O, R 3Each of the following is independently an alkyl group, an optionally substituted aryl group, or an optionally substituted heteroaryl group; each of the following is independently an optionally substituted 1- to 5-cyclic heteroaryl group containing an aryl group, a cyclopentadienyl group, or an oxygen atom, a sulfur atom, a nitrogen atom, a silicon atom, a germanium atom, or a selenium atom; G is a heteroaryl ring containing a nitrogen atom; s is an integer from 0 to 1; and t is an integer from 0 to 3.

[0023] [7] In the above general formulas (3) to (5), -(E) t - is a compound of [6], wherein - is an aryl or heteroaryl group consisting of 3 to 5 fused rings selected from substituted thiophene, furan, selenofen, thienothiophene, bithiophene, or terthiophene, or substituted benzene, thiophene, furan, selenofen, cyclopentadiene, silole, and pyrrole, J and K are each independently a substituted phenyl group, furan, thiophene, selenofen, or thienothiophene, L is a heteroaryl group consisting of 1 to 3 fused rings selected from substituted phenyl group, naphthyl group, thiophene, thienothiophene, or benzene, thiophene, furan, selenofen, cyclopentadiene, silole, and pyrrole, and G is thiadiazole, selenadiazole, triazole, benzoquinoxaline, or diphenylpyrazine.

[0024] [8] The compound of [1], wherein D in the general formula (1) is represented by the following general formula (6).

[0025] [ka]

[0026] In general formula (6), Q 1 Each of these is independently an oxygen atom, a sulfur atom, a selenium atom, and NR 3 or CR 3 =CR 3 And Ar 2Each of these is independently an alkyl group, an aryl group, or a heteroaryl group, and Ar 3 Each of these is independently either an aryl group or a heteroaryl group, or Ar 3 It is not necessary to have Y 1 ~Y 4 Each of the elements is independently a hydrogen atom, an alkyl group, an alkoxy group, or an ester group, and each of the elements a and b independently represents an integer between 1 and 3.

[0027] [9] In the above general formula (6), Q 1 is an oxygen atom or a sulfur atom, and two Ar 3 The compound according to [8], wherein the total number of rings is 0 to 3.

[0028]

[10] In the above general formula (6), Y 1 and Y 3 One of them is a hydrogen atom, and the other is an alkyl group, alkoxy group, or ester group, Y 2 and Y 4 The compound of [9] wherein one of the atoms is a hydrogen atom and the other is an alkyl group, an alkoxy group, or an ester group.

[0029]

[11] In the above general formula (6), Y 1 and Y 2 A compound of any of the above [8] to

[10] , wherein each of the groups is an independently branched alkoxy group at position 1.

[12] A composition containing any of the compounds described in [1] to

[11] above.

[13] A membrane containing any of the compounds described in [1] to

[11] above.

[14] A photoelectric element comprising the film described in

[13] .

[15] A CMOS image sensor equipped with the photoelectric conversion element described in

[14] above. [Effects of the Invention]

[0030] According to the present invention, it is possible to provide a compound having a deep HOMO level while extending the π-conjugated system in an ADA-type non-fullerene acceptor material, as well as a composition, film, photoelectric conversion element, and CMOS image sensor using this compound. [Brief explanation of the drawing]

[0031] [Figure 1] Figure 1 is a schematic cross-sectional view showing an example of a photoelectric conversion element. [Modes for carrying out the invention]

[0032] The present invention will be described in more detail below with reference to preferred embodiments, but the following description is merely one example of an embodiment of the present invention, and the present invention is not limited to the following description unless it exceeds the gist of the invention. In this specification, the "~" symbol indicating a numerical range means that the numbers before and after it are included as the lower and upper limits, respectively. In the general formula, the wavy lines indicate the bond position with adjacent groups.

[0033] [Compound] The compound of the present invention is a compound represented by the following general formula (1) (hereinafter also referred to as "compound (1)"; the same applies hereinafter). ADA ···(1)

[0034] In general formula (1), each A is independently a group represented by one of the following general formulas (2a) to (2d), at least one of the two As includes the following general formula (2a) or (2b), and D is an electron-donating group consisting of 2 to 20 cyclic groups.

[0035] [ka]

[0036] In general formulas (2a) to (2d), V 1 ~V 4 Each is independent, CR 1 or nitrogen atom, R 1 is a hydrogen atom, fluorine atom, chlorine atom, bromine atom, or cyano group, however, V 1 ~V 4 CR 1 At that time, R 1At least one of them is a cyano group. Z is an oxygen atom or a dicyanomethylene group, and Ar 1 is a substituted or unsubstituted aryl group or heteroaryl group. The crossed double bond in the above formula means that the compound may exist as an E isomer, a Z isomer, or a mixture thereof.

[0037] The compounds of the present invention have a diene structure in the A portion of the ADA-type compound that has a cyano group and / or a nitrogen-containing aromatic six-membered ring, thereby enabling the absorption wavelength to be extended while maintaining a deep HOMO level.

[0038] The reason why the compounds of the present invention can have deep HOMO levels while increasing the absorption wavelength is not clear, but it is presumed to be as follows. In conventional technology, it is known that incorporating a diene structure into a π-conjugated system to lengthen the absorption wavelength results in excessive electron density within the molecule, causing the HOMO level to rise. Furthermore, in ADA materials, the A portion, where the terminals are substituted with halogen atoms, is commonly used in conventional technology. However, halogen atoms possess lone pairs of electrons capable of hyperconjugated interactions with the molecule's π-plane, thus enriching the carbon atoms to which they are bonded, and thus contributing weakly to the relaxation of the high electron density within the diene structure. On the other hand, the A portion structure in the present invention, i.e., a cyano group and / or nitrogen-containing aromatic six-membered ring, allows for the relaxation of the high electron density within the molecule. Therefore, the rise in the HOMO level caused by the incorporation of a diene structure can be suppressed. In the case of a cyano group, the carbon atoms within the cyano group are strongly polarized (positive) and the nitrogen atoms are strongly polarized (negative). Therefore, the positively charged carbon atoms bonded to the A portion skeleton can attract electrons within the π-conjugated skeleton, thereby reducing the electron density from the D portion to the diene portion. In the case of the nitrogen-containing aromatic six-membered ring described in this application, the nitrogen atom has a lone pair of electrons orthogonal to the π-conjugated system, so it does not perturb the π-conjugated system. Furthermore, because the nitrogen atom has a higher electronegativity than the carbon atom, it is an electron-deficient heteroaromatic ring, which can alleviate the over-density of electrons from the D portion to the diene portion. As a result, it is presumed that the material in this application was able to achieve both a longer absorption wavelength and a deep HOMO level.

[0039] In the above general formula (1), A is independently a group represented by any of the above general formulas (2a) to (2d). A may be the same or different.

[0040] In the general formulas (2a) to (2d), V 1 ~V 4 Each is independent, CR 1 Or it is a nitrogen atom. R 1 is a hydrogen atom, fluorine atom, chlorine atom, bromine atom, or cyano group, however, V 1 ~V 4 CR 1 At that time, R 1 At least one of them is a cyano group. In the general formulas (2a) and (2c), V 1 ~V 4 CR 1 It is preferable that this be the case, and in this case, V 1 and V 4 R possessed 1 V is preferably a hydrogen atom. 2 and V 3 R possessed 1 It is preferable that it be a cyano group.

[0041] In the above general formulas (2a) to (2d), Z is an oxygen atom or a dicyanomethylene group, and is preferably an oxygen atom.

[0042] In the general formulas (2a) to (2d), Ar 1 is a substituted or unsubstituted aryl group or heteroaryl group. That is, Ar 1 is an optionally substituted aryl group (aromatic hydrocarbon ring) or an optionally substituted heteroaryl group (aromatic heterocycle). The number of carbon atoms in the aryl group is preferably low from the viewpoint of the material's conductivity. Therefore, the number of carbon atoms in the aryl group is preferably 18 or less, more preferably 12 or less, even more preferably 10 or less, and particularly preferably 6. The lower limit of the number of carbon atoms in the aryl group is 6. Substituents for the aryl group include alkyl groups, alkoxy groups, ester groups, hydroxyl groups, amino groups, cyano groups, fluorine atoms, and chlorine atoms. Among these, cyano groups, fluorine atoms, and chlorine atoms are preferred.

[0043] Examples of heteroaryl groups include those produced by removing one hydrogen atom from any ring atom of a heteroarene such as thiophene or pyridine, and heteroaryl groups containing an oxygen atom, a sulfur atom, a nitrogen atom, or a selenium atom are preferred. The number of carbon atoms in the heteroaryl group is preferably 17 or less, more preferably 11 or less, more preferably 9 or less, even more preferably 5 or less, and particularly preferably 4 or 5. The lower limit for the number of carbon atoms in the heteroaryl group is 4. Substituents for the heteroaryl group include alkyl groups, alkoxy groups, ester groups, hydroxyl groups, amino groups, cyano groups, fluorine atoms, and chlorine atoms. Among these, cyano groups, fluorine atoms, and chlorine atoms are preferred. In the above general formulas (2b) and (2d), Ar 1 An aryl group is preferred, and a phenyl group is more preferred.

[0044] Regarding A, in terms of extending the absorption wavelength, it is preferable that the two A's are the same rather than different, and it is more preferable that they be selected from general formula (2a) or (2b), and even more preferable that they be selected from general formula (2a) in terms of ease of synthesis. On the other hand, in terms of having a low dark current in the photoelectric conversion element, it is preferable that the two A's are different rather than identical, and it is more preferable that the combination of the two A's is the combination of general formula (2a) and (2c), or the combination of general formula (2b) and (2d), and even more preferable that they be selected from the combination of general formula (2a) and (2c) in terms of ease of synthesis. Furthermore, it is preferable that the two A's are either (2a') or (2c') respectively, or (2b') or (2d') respectively.

[0045] [ka]

[0046] In general formulas (2b') and (2d'), R 2 Each of these is independently a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, or a cyano group.

[0047] D is preferably a group represented by any of the following general formulas (3) to (5).

[0048] [ka]

[0049] In general formulas (3) to (5), W is C - (R 3 )2, Si-(R 3 )2, Ge-(R 3 )2, NR 3 , OC(R 3 )2, or C(R 3 )2-O, R 3Each of the following is independently an alkyl group, an optionally substituted aryl group, or an optionally substituted heteroaryl group; each of the following is independently an optionally substituted 1- to 5-cyclic heteroaryl group containing an aryl group, a cyclopentadienyl group, or an oxygen atom, a sulfur atom, a nitrogen atom, a silicon atom, a germanium atom, or a selenium atom; G is a heteroaryl ring containing a nitrogen atom; s is an integer from 0 to 1; and t is an integer from 0 to 3. Examples of substituents that may be substituted include hydrogen atoms, fluorine atoms, chlorine atoms, nitro groups, cyano groups, alkyl groups, alkoxy groups, and ester groups.

[0050] In the general formulas (3) to (5) above, W is C-(R 3 )2, Si-(R 3 )2, Ge-(R 3 )2, NR 3 O-CR 3 , or CR 3 -O and R 3 Each of these is independently an alkyl group, an optionally substituted aryl group, or an optionally substituted heteroaryl group. 3 The number of carbon atoms in the alkyl group is preferably small from the standpoint of the material's conductivity. Therefore, R 3 The number of carbon atoms in the alkyl group is preferably 30 or less, more preferably 20 or less, even more preferably 15 or less, and particularly preferably 10 or less. 3 The alkyl group preferably has 2 or more carbon atoms, more preferably 4 or more, and even more preferably 6 or more. R 3 The alkyl group may be linear or cyclic. If the alkyl group is linear, it may be linear or branched. Examples of alkyl groups include methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, decyl, dodecyl, isopropyl, 2-ethylhexyl, 2-hexyloctyl, and cyclohexyl groups. 3 The aryl group and heteroaryl group are the Ar 1Examples of the aryl group and heteroaryl group exemplified above in the description include those.

[0051] In the general formulas (3) to (5), E is composed of 1 to 5 rings, and is an aryl group, a cyclopentadienyl group, or a heteroaryl group containing an oxygen atom, a sulfur atom, a nitrogen atom, a silicon atom, a germanium atom, or a selenium atom. -(E) t - is preferably a thiophene, furan, selenophene, thienothiophene, bithiophene or terthiophene which may be substituted, or an aryl group or heteroaryl group composed of 3 to 5 condensed rings selected from benzene, thiophene, furan, selenophene, cyclopentadiene, silole and pyrrole which may be substituted. Specific examples of the heteroaryl group composed of 3 condensed rings selected from benzene, thiophene, furan, selenophene, cyclopentadiene, silole and pyrrole include dibenzothiophene, dibenzofuran, dibenzosilole, carbazole, dithienocyclopentadiene, dithienosilole, dithienogermole, dithienothiophene, dithienopyrrole. Among these, dithienocyclopentadiene, dithienosilole, dithienogermole, dithienopyrrole are preferred, dithienocyclopentadiene, dithienosilole are more preferred, and dithienocyclopentadiene is even more preferred. As the heteroaryl group composed of 4 condensed rings selected from benzene, thiophene, furan, selenophene, cyclopentadiene, silole and pyrrole, a heteroaryl group composed of 4 condensed rings selected from thiophene, cyclopentadiene, silole and pyrrole is preferred, and a heteroaryl group in which both ends of the 4 condensed rings are thiophene and which contains a total of 2 to 3 rings of thiophene is more preferred.

[0052] In the general formulas (3) to (5), J and K are each independently composed of 1 to 5 rings, and are an aryl group, a cyclopentadienyl group, or a heteroaryl group containing an oxygen atom, a sulfur atom, a nitrogen atom, a silicon atom, a germanium atom, or a selenium atom. J and K are each preferably independently a substituted phenyl group, furan, thiophene, selenofen, or thienothiophene.

[0053] In the general formulas (3) to (5) above, L consists of 1 to 5 rings and is an aryl group, a cyclopentadienyl group, or a heteroaryl group containing an oxygen atom, a sulfur atom, a nitrogen atom, a silicon atom, a germanium atom, or a selenium atom. L is preferably a heteroaryl group consisting of 1-3 fused rings, selected from substituted phenyl, naphthyl, thiophene, thienothiophene, or benzene, thiophene, furan, selenofene, cyclopentadiene, silole, and pyrrole. Specific examples of heteroaryl groups consisting of a tricyclic structure selected from benzene, thiophene, furan, selenofen, cyclopentadiene, silole, and pyrrole include dibenzothiophene, dibenzofuran, dibenzosilole, carbazole, dithienocyclopentadiene, dithienosilole, dithienogenmol, dithienothiophene, and dithienopyrrole. Among these, dithienocyclopentadiene, dithienosilole, dithienothiophene, and dithienopyrrole are preferred, dithienocyclopentadiene, dithienosilole, and dithienopyrrole are more preferred, and dithienocyclopentadiene is even more preferred.

[0054] In the general formulas (3) to (5) above, G is a heteroaryl ring containing a nitrogen atom. G is preferably thiadiazole, selenadiazole, triazole, benzoquinoxaline, or diphenylpyrazine. s is a number between 0 and 1. t is a number between 0 and 3.

[0055] As for compound (1), it is preferable that D in the general formula (1) is a group represented by the general formula (3) or (4), and it is preferable that D is a group represented by the following general formula (6).

[0056] [ka]

[0057] In general formula (6), Q 1 is each independently an oxygen atom, a sulfur atom, a selenium atom, N-R 3 or CR 3 =CR 3 and Ar 2 is each independently an alkyl group, an aryl group or a heteroaryl group, and Ar 3 is each independently an aryl group or a heteroaryl group, or Ar 3 may not have. Y 1 ~Y 4 is each independently a hydrogen atom, an alkyl group, an alkoxy group or an ester group, and a and b each independently represent an integer of 1 or more and 3 or less.

[0058] Y in the general formula (6) 1 ~Y 4 is such that one of Y 1 and Y 3 is a hydrogen atom and the other is an alkyl group, an alkoxy group or an ester group, and one of Y 2 and Y 4 is a hydrogen atom and the other is an alkyl group, an alkoxy group or an ester group, and it is preferable that one of Y 3 and Y 4 is a hydrogen atom and one of Y 1 and Y 2 is an alkyl group, an alkoxy group or an ester group.

[0059] Ar in the general formula (6) 2 is preferably an alkyl group or an aryl group.

[0060] In the general formula (6), Q 1 is preferably an oxygen atom or a sulfur atom, and more preferably a sulfur atom.

[0061] In the general formula (6), Ar 3is a group selected from benzene, thiophene, furan, selenofene, cyclopentadiene, silole and pyrrole, which may be substituted, or Ar 3 It does not have to have two Ar 3 The total number of rings is preferably 0 to 3, and the group is selected from thiophene, furan and cyclopentadiene, which may be substituted or Ar 3 It does not have to have two Ar 3 It is more preferable that the total number of rings is 0 to 3, Ar 3 It is even more preferable that it does not have. From another perspective, one Ar 3 A group having 1 to 3 rings selected from thiophene or cyclopentadiene, which may be substituted, and the other Ar 3 It is even more preferable that it does not have one Ar 3 A group with 2-3 rings selected from thiophene or cyclopentadiene, which may be substituted, and the other Ar 3 It is even more preferable that it does not have Ar 3 It is a thiophene with two rings, and the other Ar 3 It is particularly preferable that it does not have. From another perspective, one Ar 3 It is a tricyclic group in which two thiophenes may be substituted and one cyclopentadiene may be substituted, and the other Ar 3 It is particularly preferable that it does not have [this feature].

[0062] In the above general formula (6), Y 1 ~Y 4 Each of these is independently a hydrogen atom, an alkyl group, an alkoxy group, or an ester group. Y 1 ~Y 4 As for the alkyl group, the R 3 The alkyl groups mentioned earlier are cited as examples in the explanation. Y 1 ~Y 4The alkyl group may be linear or cyclic. If the alkyl group is linear, it may be linear or branched. From the viewpoint of ease of synthesis, it is preferable that the alkyl group is linear or branched in which the carbon atom bonded to the thiophene ring is a primary carbon atom. From the viewpoint of solubility of the material, it is preferable that the alkyl group is branched in which the carbon atom bonded to the thiophene ring is a primary carbon atom, or that the alkyl group is linear, branched, or cyclic in which the carbon atom bonded to the thiophene ring is a secondary carbon atom. From the viewpoint of ease of synthesis and solubility, it is even more preferable that the alkyl group is branched in which the carbon atom bonded to the thiophene ring is a primary carbon atom.

[0063] Y 1 ~Y 4 The number of carbon atoms in the alkoxy group is preferably small from the standpoint of the conductivity of the material. Therefore, Y 1 ~Y 4 The number of carbon atoms in the alkoxy group is preferably 30 or less, more preferably 20 or less, even more preferably 15 or less, and particularly preferably 10 or less. 1 ~Y 4 The alkoxy group preferably has 2 or more carbon atoms, more preferably 4 or more, and even more preferably 6 or more. The above upper and lower limits can be combined in any way. For example, it may be 2 to 30, 2 to 20, 2 to 15, 4 to 15, 6 to 15, or 6 to 10. Examples of alkoxy groups include methoxy, ethoxy, propyloxy, butoxy, pentyloxy, hexyloxy, octyloxy, decyloxy, dodecyloxy, isopropyloxy, 2-ethylhexyloxy, 2-hexyloctyloxy, and cyclohexyloxy groups.

[0064] An alkoxy group has a structure in which an alkyl group is bonded to an oxygen atom, and the alkyl group bonded to the oxygen atom may be linear or cyclic. When the alkyl group bonded to the oxygen atom is linear, it may be linear or branched. In terms of ease of synthesis, it is preferable that the carbon atom bonded to the oxygen atom is a linear or branched alkyl group in which the carbon atom is a primary carbon atom. In terms of solubility of the material, it is preferable that the carbon atom bonded to the oxygen atom is a branched alkyl group in which the carbon atom is a primary carbon atom, or a linear, branched, or cyclic alkyl group in which the carbon atom bonded to the oxygen atom is a secondary carbon atom, more preferably a linear, branched, or cyclic alkyl group in which the carbon atom bonded to the oxygen atom is a secondary carbon atom, and even more preferably a linear or branched alkyl group in which the carbon atom bonded to the oxygen atom is a secondary carbon atom.

[0065] As for the alkoxy group branched at position 1, alkoxy groups having 2 to 30 carbon atoms are preferred, alkoxy groups having 3 to 20 carbon atoms are more preferred, alkoxy groups having 3 to 15 carbon atoms are even more preferred, alkoxy groups having 4 to 10 carbon atoms are even more preferred, and alkoxy groups having 5 to 8 carbon atoms are particularly preferred. Examples of alkoxy groups branched at position 1 include isopropyloxy group, t-butyloxy group, 1-ethyl-propyloxy group, 1-methyl-pentyloxy group, 1-ethyl-pentyloxy group, 1-methyl-hexyloxy group, 1-ethyl-hexyloxy group, 1-propyl-heptyloxy group, 1-butyl-pentyloxy group, 1-butyl-heptyloxy group, 1-ethyl-octyloxy group, cyclopentyloxy group, 1-octyl-nonyloxy group, 1,1-dimethyl-pentyloxy group, 1,1-dimethyl-heptyloxy group, 1-methyl-1-propyl-hexyloxy group, and 1,1-dimethyl-pentadecyloxy group.

[0066] Y 1 ~Y 4 Examples of ester groups include monovalent groups having an ester bond. Specifically, examples include the group represented by the following general formula (i). -COO-R 7 ...(i)

[0067] In general formula (i), R 7 R is an alkyl group or an aryl group. 7 As for the alkyl group, the R 3 The alkyl groups mentioned earlier are cited as examples in the explanation.

[0068] In the above general formula (i), R 7 The alkyl group may be linear or cyclic. If the alkyl group is linear, it may be linear or branched. In terms of ease of synthesis, it is preferable that the alkyl group is linear or branched in which the carbon atom bonded to the oxygen atom is a primary carbon atom. In terms of solubility of the material, it is preferable that the alkyl group is branched in which the carbon atom bonded to the oxygen atom is a primary carbon atom, or linear, branched, or cyclic in which the carbon atom bonded to the oxygen atom is a secondary carbon atom, more preferably linear, branched, or cyclic in which the carbon atom bonded to the oxygen atom is a secondary carbon atom, and even more preferably linear or branched in which the carbon atom bonded to the oxygen atom is a secondary carbon atom.

[0069] R 7 The aryl group is the aforementioned Ar 1 The aryl group, which was exemplified earlier in the explanation, is one example. R 7 The aryl group may or may not have substituents. That is, R 7 The aryl group is either unsubstituted or substituted. Examples of substituents include alkyl groups, alkoxy groups, ester groups, hydroxyl groups, and amino groups.

[0070] Y 1 ~Y 4 They may be the same or different. In particular, Y is chosen because it is easy to form a lamellar structure in a film obtained using the compound of the present invention. 1 and Y 3 One of them is a hydrogen atom, and the other is an alkyl group, alkoxy group, or ester group, Y 2 and Y4 Preferably, one of the atoms is a hydrogen atom and the other is an alkyl group, alkoxy group, or ester group, and among these, in particular, in terms of extending the absorption wavelength, Y 1 It is preferable that the substituent is an alkoxy group. In particular, Y is preferable because the orientation of the substituents becomes parallel, making it easier to form a lamellar structure. 2 and Y 3 Y is a hydrogen atom, 1 and Y 4 It is more preferable that the group is an alkyl group, an alkoxy group, or an ester group. Furthermore, in terms of extending the absorption wavelength, Y 1 and Y 2 Each of them is independently an alkoxy group, Y 3 and Y 4 It is preferable that it is a hydrogen atom, and among them, Y is particularly preferable in terms of ease of synthesis. 1 and Y 2 It is more preferable that they are the same. Also, Y 1 and Y 2 It is even more preferable that each of these groups is an independently branched alkoxy group at position 1. Furthermore, in another aspect, as an n-type material for a photoelectric conversion element, Y has a deep HOMO level. 1 and Y 3 One of them is a hydrogen atom, and the other is an alkyl group, alkoxy group, or ester group, Y 2 and Y 4 Preferably, one of the atoms is a hydrogen atom, and the other is an alkyl group, an alkoxy group, or an ester group.

[0071] When D in compound (1) is a group represented by the general formula (6), preferred forms include the following general formulas (6a) to (6i).

[0072] [ka]

[0073] Among these, general formulas (6a), (6b), (6c), (6d), (6f), and (6i) are more preferred, and general formulas (6a), (6b), and (6c) are even more preferred.

[0074] As for compound (1), it is more preferable that D in the general formula (1) is a group represented by the general formula (6a'), and as such a compound, a compound represented by the following general formula (6a') (hereinafter also referred to as "compound (6a')") is preferred.

[0075] [ka]

[0076] In general formula (6a'), A is independently a group represented by any of the general formulas (2a) to (2d), and Y 1 ~Y 4 Each of the following is independently a hydrogen atom, an alkyl group, an alkoxy group, or an ester group, and M is a carbon atom substituted with an alkyl or aryl group, a nitrogen atom substituted with an alkyl or aryl group, a silicon atom substituted with an alkyl or aryl group, or a germanium atom substituted with an alkyl or aryl group.

[0077] A in the aforementioned general formula (6a') and its preferred embodiment are the same as A in the aforementioned general formula (1) and its preferred embodiment.

[0078] In the above general formula (6a'), Y 1 ~Y 4 Each of these is independently a hydrogen atom, an alkyl group, an alkoxy group, or an ester group. Y 1 ~Y 4 The alkyl group, alkoxy group, or ester group is Y in the general formula (6) above. 1 ~Y 4 The examples given earlier in the explanation are cited.

[0079] In the general formula (6a') above, M is a carbon atom substituted with an alkyl or aryl group, a nitrogen atom substituted with an alkyl or aryl group, a silicon atom substituted with an alkyl or aryl group, or a germanium atom substituted with an alkyl or aryl group. Compound (6a') is thought to have increased solubility because M is a carbon atom substituted with an alkyl or aryl group, a nitrogen atom substituted with an alkyl or aryl group, a silicon atom substituted with an alkyl or aryl group, or a germanium atom substituted with an alkyl or aryl group.

[0080] A carbon atom substituted with an alkyl or aryl group is represented by the following general formula (ii). A nitrogen atom substituted with an alkyl or aryl group is represented by the following general formula (iii). A silicon atom substituted with an alkyl or aryl group is represented by the following general formula (iv). A germanium atom substituted with an alkyl or aryl group is represented by the following general formula (v).

[0081] [ka]

[0082] In general formulas (ii) to (v), R 8 ~R 14 Each of these is independently an alkyl group or an aryl group. R 8 ~R 14 As for the alkyl group, the R 3 The alkyl groups mentioned earlier are cited as examples in the explanation. R 8 ~R 14 The aryl group is the aforementioned Ar 1 The aryl group, which was exemplified earlier in the explanation, is one example. R 8 ~R 14 The aryl group may or may not have substituents. That is, R 8 ~R14 The aryl group is either unsubstituted or substituted. Examples of substituents include alkyl groups, alkoxy groups, ester groups, hydroxyl groups, and amino groups.

[0083] In terms of ease of synthesis of compound (6a'), it is preferable that the two alkyl or aryl groups of the carbon, silicon, and germanium atoms in M ​​are identical. In terms of synthesis cost, M is preferably a carbon atom substituted with an alkyl or aryl group, a nitrogen atom substituted with an alkyl or aryl group, or a silicon atom substituted with an alkyl or aryl group. Among these, in terms of extending the absorption wavelength, a carbon atom substituted with an alkyl or aryl group or a nitrogen atom substituted with an alkyl or aryl group is more preferable, a carbon atom substituted with an alkyl group or a nitrogen atom substituted with an alkyl group is even more preferable, and a carbon atom substituted with an alkyl group is particularly preferable.

[0084] As for compound (6a'), each A in the general formula (6a') is independently a group represented by any of the general formulas (2a) to (2d), and Y 1 and Y 2 They are identical, and are alkoxy groups branched at position 1, Y 3 and Y 4 Compounds in which is a fluorine atom, a chlorine atom, or a cyano group, and M is a carbon atom substituted with an alkyl group or an aryl group, or a nitrogen atom substituted with an alkyl group or an aryl group are preferred. Among these, compounds in which Z in the above general formulas (2a) to (2d) is an oxygen atom are more preferred.

[0085] Specific examples of compound (1) include the compound represented by the following formula, but compound (1) is not limited to these.

[0086] [ka]

[0087] [ka]

[0088]

change

[0089]

change

[0090]

change

[0091]

change

[0092]

change

[0093]

change

[0094]

change

[0095]

change

[0096]

change

[0097]

change

[0098] [ka]

[0099] [ka]

[0100] [ka]

[0101] [ka]

[0102] [ka]

[0103] The method for producing compound (1) is not particularly limited, but as an example of a method for producing compound (1), the method for producing compound (A) shown in the following formula will be specifically explained. In compound (A), Y is the same as Y in compound (6a). 1 ~Y 4 It corresponds to one of the following.

[0104] [ka]

[0105] First, compound (B) shown below is reacted with lithium diisopropylamide (LDA) in a reaction solvent, and then N,N-dimethylformamide is reacted further to obtain compound (C) shown below.

[0106] [ka]

[0107] Here, compound (B) may be synthesized by known methods or a commercially available product may be used. The preferred ratio of the raw materials is 0.9 to 1.5 equivalents of LDA and 0.9 equivalents or more of N,N-dimethylformamide relative to compound (B). N-formylpiperidine may be used instead of N,N-dimethylformamide. The reaction solvent is not particularly limited as long as it does not react with the raw material compounds, and examples include saturated aliphatic hydrocarbon solvents such as hexane; ether solvents such as tetrahydrofuran (THF), diethyl ether, cyclopentyl methyl ether, and methyl t-butyl ether; and aromatic hydrocarbon solvents such as toluene and xylene. The reaction temperature is preferably -78 to 50°C. The reaction time is preferably 10 minutes to 12 hours after adding LDA, and 10 minutes to 12 hours after adding N,N-dimethylformamide.

[0108] In the preparation of compound (A), compound (E) shown below may be used instead of compound (C). Compound (E) can be obtained, for example, as follows.

[0109] Specifically, first, the 3-substituted thiophene shown below is reacted with lithium diisopropylamide (LDA) in a reaction solvent, and then 1,2-dibromo-1,1,2,2-tetrachloroethane is further reacted to obtain compound (D) shown below.

[0110] [ka]

[0111] Here, the 3-substituted thiophene may be synthesized by known methods or a commercially available product may be used. The preferred ratio of raw materials is 0.9 to 1.5 equivalents of LDA relative to the 3-substituted thiophene, and 0.9 equivalents or more of 1,2-dibromo-1,1,2,2-tetrachloroethane. The reaction solvent is not particularly limited as long as it does not react with the starting compound, and examples include saturated aliphatic hydrocarbon solvents such as hexane; ether solvents such as tetrahydrofuran (THF), diethyl ether, cyclopentyl methyl ether, and methyl t-butyl ether; and aromatic hydrocarbon solvents such as toluene and xylene. The reaction temperature is preferably -78 to 50°C. The reaction time is preferably 10 minutes to 12 hours after adding LDA, and 10 minutes to 12 hours after adding 1,2-dibromo-1,1,2,2-tetrachloroethane.

[0112] Next, compound (D) and lithium diisopropylamide (LDA) are reacted in a reaction solvent, and then N,N-dimethylformamide is reacted further to obtain compound (E) shown in the formula below.

[0113] [ka]

[0114] The preferred ratio of raw materials is 0.9 to 1.5 equivalents of LDA and 0.9 equivalents or more of N,N-dimethylformamide relative to compound (D). N-formylpiperidine may be used instead of N,N-dimethylformamide. The reaction solvent is not particularly limited as long as it does not react with the raw material compounds. Examples include saturated aliphatic hydrocarbon solvents such as hexane; ether solvents such as tetrahydrofuran (THF), diethyl ether, cyclopentyl methyl ether, and methyl t-butyl ether; and aromatic hydrocarbon solvents such as toluene and xylene. The reaction temperature is preferably -78 to 50°C. The reaction time is preferably 10 minutes to 12 hours after adding LDA, and 10 minutes to 12 hours after adding N,N-dimethylformamide.

[0115] Next, in the reaction solvent, a cross-coupling reaction is carried out between at least one of compound (C) and compound (E) and compound (F) of the following formula to obtain compound (G) of the following formula. The method for producing compound (G) is not particularly limited, but it can be produced by a method similar to that described in literature such as Adv. Energy Mater., 2018, Vol. 8, p. 1801212.; J. Mater. Chem. C, 2020, Vol. 8, p. 15175.; ACS Energy Lett., 2019, Vol. 4, p. 1401. An example of specific production conditions is as follows.

[0116] [ka]

[0117] Here, compound (F) may be synthesized by known methods (e.g., Polym. Chem., 2013, Vol. 4, pp. 5351-5360; J. Phys. Chem. C, 2011, Vol. 15, pp. 2398-2405; Chem. Commun., 2012, Vol. 48, pp. 11130-11132), or a commercially available compound may be used. Alternatively, compound (F) may be used depending on the cross-coupling reaction (where "L" in compound (F) is an alkyltin group, boric acid, a borate ester group, a zinc halide, a magnesium halide, or a silyl group, etc.).

[0118] The type of cross-coupling reaction between compound (C) and compound (E) and compound (F) is not particularly limited, and can be carried out by Stille coupling, Suzuki coupling, Negishi coupling, Kumada coupling, Hiyama coupling, etc. The cross-coupling reaction may be carried out in the presence of a catalyst such as a palladium catalyst, nickel catalyst, or copper catalyst. When compound (C) or compound (E) is reacted with compound (F) by Stille coupling reaction, the charging ratio of the raw materials is preferably 1.9 to 3.0 equivalents of compound (C) or compound (E) relative to compound (F). When compound (C) and compound (E) are reacted with compound (F) by Stille coupling reaction, the charging ratio of the raw materials is preferably 0.9 to 1.1 equivalents each of compound (C) and compound (E) relative to compound (F). Furthermore, it is preferable to use a palladium catalyst in the Stille coupling reaction, and the palladium content in the catalyst is preferably 0.1 to 50 mol%.

[0119] The reaction solvent is not particularly limited as long as it does not react with the starting compound, and examples include saturated aliphatic hydrocarbon solvents such as hexane; ether solvents such as diethyl ether, cyclopentyl methyl ether, tetrahydrofuran (THF), and 1,4-dioxane; aromatic hydrocarbon solvents such as toluene and xylene; and N,N-dimethylformamide (DMF), dimethyl sulfoxide, and N-methyl-2-pyrrolidone. The reaction temperature is preferably between 20°C and the reflux temperature of the reaction solvent. The reaction time is preferably 1 to 24 hours.

[0120] Next, compound (G) is reacted with Wittig reagent in the reaction solvent to obtain compound (J). The method for producing compound (J) is not particularly limited, but compound (J) can be produced by a method similar to those described in literature such as WO2019 / 185578, WO2019 / 185580, and KR2024 / 2448. An example of specific production conditions is as follows.

[0121] [ka]

[0122] The reaction solvent is not particularly limited as long as it does not react with the starting compound, and examples include saturated aliphatic hydrocarbon solvents such as hexane; ether solvents such as tetrahydrofuran (THF), diethyl ether, cyclopentyl methyl ether, and methyl t-butyl ether; and aromatic hydrocarbon solvents such as toluene and xylene. Examples of basic reagents include NaH, BuLi, tBuOK, EtONa, and MeONa. The reaction temperature is preferably -78 to 50°C. The reaction time is preferably between 10 minutes and 48 hours.

[0123] Finally, compound (J) and compound (I) are reacted in the reaction solvent in the presence of an acid catalyst to obtain compound (A). The method for producing compound (A) is not particularly limited, but for example, compound (A) can be produced by a method similar to that described in Japanese Patent Publication No. 2022-511781 and Japanese Patent Publication No. 2023-500815. An example of specific production conditions is as follows.

[0124] [ka]

[0125] Here, compound (I) can be synthesized by known methods (for example, Japanese Patent Publication No. 2022-511781, Japanese Patent Publication No. 2023-500815, WO2024 / 170695). Examples of acid catalysts include p-toluenesulfonic acid hydrate (PTSA·H2O). Examples of base catalysts include pyridine and piperidine. The preferred ratio of raw materials is 1.9 to 10 equivalents of compound (I) to compound (G). The preferred amount of p-toluenesulfonic acid hydrate is 2.1 to 11 equivalents. The reaction solvent is not particularly limited as long as it does not react with the starting compound. For example, an alcohol-based solvent such as methanol or ethanol may be mixed with an aromatic hydrocarbon solvent such as toluene or xylene. The reaction temperature is preferably between room temperature and reflux temperature. The reaction time is preferably 1 to 6 hours.

[0126] In this way, compound (A) can be produced. Here, Y in compound (A) is the same as Y in compound (1). 1 ~Y 4 It will be one of the following, and Z in compound (A) is Z in compound (1). 1 or Z 2 This is the result.

[0127] The compounds of the present invention are suitable as n-type semiconductor materials (light-absorbing and electron-transporting materials) used in photoelectric conversion elements because they can have a deep HOMO level while extending the absorption wavelength of the photoelectric conversion element. The applications of the compounds of the present invention are not limited to those described above. For example, since the compounds of the present invention also have excellent luminescence properties, they can be used in bioimaging, organic EL, infrared luminescent dyes for wavelength conversion films and compositions, and the like.

[0128] [Composition] The composition of the present invention contains the above-described compound (1). Compound (1) may be used alone, or two or more compounds may be used in any proportion and combination. The content of compound (1) in the composition of the present invention is not particularly limited. However, when the composition of the present invention is used for forming the photoelectric conversion layer (active layer) of a photoelectric conversion element, it is preferable that the content of compound (1) be high in terms of light absorption, and low in terms of carrier balance. Therefore, the content of compound (1) in the composition of the present invention is preferably 10% by mass or more, more preferably 25% by mass or more, and even more preferably 40% by mass or more, relative to the total amount (total mass) of all components other than the solvent. Furthermore, the content of compound (1) in the composition of the present invention is preferably 100% by mass or less, more preferably 90% by mass or less, even more preferably 75% by mass or less, and particularly preferably 60% by mass or less, relative to the total amount (total mass) of all components other than the solvent.

[0129] The composition of the present invention may further contain, in addition to compound (1), an n-type semiconductor material other than compound (1). The n-type semiconductor material other than compound (1) is not particularly limited as long as it is not the compound represented by the general formula (1). Two or more types of n-type semiconductor materials other than compound (1) may be used, and in such cases, they may be used in any proportion and combination. The content of n-type semiconductor materials other than compound (1) in the composition of the present invention is not particularly limited. From the viewpoint of carrier balance adjustment, the content of n-type semiconductor materials other than compound (1) relative to the total amount (total mass) of all components other than the solvent in the composition of the present invention is preferably 5% by mass or more, more preferably 25% by mass or more, and even more preferably 50% by mass or more. Furthermore, from the viewpoint of carrier balance adjustment, the content of n-type semiconductor materials other than compound (1) relative to the total amount (total mass) of all components other than the solvent in the composition of the present invention is preferably 95% by mass or less, more preferably 90% by mass or less, and even more preferably 85% by mass or less.

[0130] The composition of the present invention may further contain a solvent. A composition containing compound (1) and a solvent is suitable as an ink (active layer forming composition) for forming the photoelectric conversion layer (active layer) of a photoelectric conversion element. As a solvent, a liquid that does not react with compound (1) but dissolves compound (1) is preferred, such as aromatic hydrocarbon solvents like toluene and xylene; or halogenated solvents like dichloromethane and chloroform. If the composition of the present invention contains a solvent, the solvent may be used alone or two or more solvents in any proportion or combination. If the composition of the present invention contains a solvent, the content of compound (1) in the composition of the present invention is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1.0% by mass or more, based on the total mass of the composition of the present invention. Furthermore, the content of compound (1) is preferably 5.0% by mass or less, more preferably 3.5% by mass or less, and even more preferably 2.0% by mass or less, based on the total mass of the composition of the present invention.

[0131] When the composition of the present invention is used as an active layer forming composition, it is preferable that the composition further contains a p-type semiconductor material in addition to compound (1). The p-type semiconductor material is not particularly limited as long as it is used in the photoelectric conversion layer of an organic photoelectric conversion element, but examples include polymers described in the literature (ACS Energy Lett., 2019, Vol. 4, p. 1401. and Adv. Optical Mater., 2022, Vol. 10, p. 2200747.). When the composition of the present invention contains a p-type semiconductor material, the p-type semiconductor material may be used alone or two or more types may be used in any proportion and combination. The mass ratio of compound (1) to the p-type semiconductor material (compound (1) / p-type semiconductor material) is preferably 0.1 or higher, more preferably 0.5 or higher, and even more preferably 0.75 or higher. Furthermore, the mass ratio of compound (1) to the p-type semiconductor material is preferably 3.0 or lower, more preferably 2.0 or lower, and even more preferably 1.5 or lower.

[0132] The composition of the present invention may further contain components other than compound (1), a p-type semiconductor material, and a solvent (optional components) as needed, as long as they do not impair the effects of the present invention. Examples of optional components include 1,8-diiodooctane, 1-chloronaphthalene, and [6,6]-phenyl-C61-butyrate methyl. If the composition of the present invention contains optional components, these optional components may be used alone or in any combination of two or more components in any proportion. When an optional component is included, a higher content of the optional component is preferable in that the effects of including the optional component are more likely to manifest. On the other hand, a higher content of compound (1) is preferable in that the composition of the present invention is more likely to maintain suitable physical properties as a photoelectric conversion element. Therefore, when the composition of the present invention includes an optional component, the content of the optional component is preferably 0.1% by mass or more, and more preferably 0.3% by mass or more, relative to the total amount (total mass) of all components other than the solvent in the composition of the present invention. Furthermore, the content of the optional component is preferably 2.0% by mass or less, and more preferably 1.0% by mass or less, relative to the total amount (total mass) of all components other than the solvent in the composition of the present invention.

[0133] The compositions of the present invention can be obtained, for example, by dissolving compound (1) in a solvent and, if necessary, a p-type semiconductor material and one or more optional components. Furthermore, by removing the solvent from the obtained composition, a solvent-free composition of the present invention can be obtained.

[0134] The composition of the present invention is suitable as an ink (active layer forming composition) for forming the photoelectric conversion layer (active layer) of a photoelectric conversion element.

[0135] [film] The film of the present invention is a film containing the above-mentioned compound (1), and is also called an organic thin film. The film of the present invention can be obtained, for example, by removing the solvent from the composition of the present invention, which contains the solvent as described above. Specifically, it can be obtained by coating the composition of the present invention onto a substrate and then drying it. The content of compound (1) in the membrane is the same as the content of compound (1) relative to the total amount (total mass) of all components other than the solvent in the composition of the present invention described above. That is, the content of compound (1) relative to the total mass of the membrane is preferably 10% by mass or more, more preferably 25% by mass or more, and even more preferably 40% by mass or more. Furthermore, the content of compound (1) relative to the total mass of the membrane is preferably 100% by mass or less, more preferably 90% by mass or less, even more preferably 75% by mass or less, and particularly preferably 60% by mass or less.

[0136] In terms of light absorption, a thicker film thickness is preferable. On the other hand, in terms of external quantum efficiency (EQE) when the film of the present invention is used as the photoelectric conversion layer (active layer) of a photoelectric conversion element, a thinner film thickness is preferable. Therefore, the film thickness is preferably 10 nm or more, and more preferably 50 nm or more. Furthermore, the film thickness is preferably 3000 nm or less, and more preferably 2000 nm or less. The film thickness can be adjusted by the amount of composition applied to the substrate.

[0137] The method of applying the composition is not particularly limited, but examples include brush application, bar coating, spray coating, dip coating, spin coating, blade coating, curtain coating, etc. The drying temperature after application is preferably 20 to 250°C. The drying time is preferably between 10 minutes and 5 hours.

[0138] The film of the present invention is suitable as a photoelectric conversion layer (active layer) of a photoelectric conversion element.

[0139] [Photoelectric conversion element] The photoelectric conversion element of the present invention is an element comprising the film of the present invention as described above, and is also called an organic photoelectric conversion element. Specifically, the photoelectric conversion element of the present invention comprises the film of the present invention as a photoelectric conversion layer (active layer). The structure of the photoelectric conversion element can adopt the structure of a known organic photoelectric conversion element. For example, reference can be made to the description in Japanese Patent Application Laid-Open No. 2007-324587. Although the specific structure is not particularly limited, for example, an element having a laminated structure in which a photoelectric conversion layer (active layer) is sandwiched between a pair of electrodes can be mentioned.

[0140] Hereinafter, an example of the photoelectric conversion element of the present invention will be described with reference to FIG. 1. In addition, in each drawing used in the following description, for the sake of easy understanding of its features, there are cases where the characteristic portions are enlarged for convenience, and the dimensional ratios of each component may be different from the actual ones. Further, the materials, dimensions, etc. exemplified in the following description are merely examples, and the present invention is not limited thereto, and it can be appropriately changed and implemented within the range not changing the gist thereof.

[0141] The photoelectric conversion element 10 shown in FIG. 1 has a structure in which a transparent electrode 12, a hole transport layer 13, a photoelectric conversion layer 14, an electron transport layer 15, and a metal electrode 16 are laminated in this order on a transparent substrate 11. Note that the positions of the hole transport layer 13 and the electron transport layer 15 may be exchanged. That is, the photoelectric conversion element may have a structure in which a transparent electrode, an electron transport layer, a photoelectric conversion layer (active layer), a hole transport layer, and a metal electrode are laminated in this order on a transparent substrate.

[0142] Examples of the transparent substrate 11 include a substrate having an average transmittance of 80% or more in visible light of 450 nm or more. Examples of the material for forming the transparent substrate 11 include glass; plastics such as polyethylene terephthalate, polyethylene naphthalate, polycarbonate, and polyethylene sulfide.

[0143] Examples of the transparent electrode 12 include an electrode having an average transmittance of 80% or more in visible light of 450 nm or more. The material used to form the transparent electrode 12 is not particularly limited as long as it can form the transparent electrode 12, but examples include tin-doped indium oxide (ITO), zinc-doped indium oxide (IZO), tungsten-doped indium oxide (IWO), zinc-aluminum oxide (AZO), indium oxide (In2O3), zinc oxide (ZnO), titanium oxide (TiO2), and the like.

[0144] The metal electrode 16 is an electrode that is paired with the transparent electrode 12. The material constituting the metal electrode 16 is not particularly limited, but examples include metals or alloys thereof such as gold, platinum, silver, aluminum, nickel, titanium, magnesium, calcium, barium, sodium, chromium, copper, and cobalt. The metal electrode 16 is preferably a transparent electrode or a reflective electrode. That is, the photoelectric conversion element is preferably a laminated structure in which a photoelectric conversion layer (active layer) is sandwiched between a pair of electrodes (transparent or metal), and more preferably a laminated structure in which an electron transport layer, a photoelectric conversion layer (active layer), and a hole transport layer are sandwiched between a pair of electrodes (transparent or metal). In the case of a pair of transparent electrodes, the materials forming the electrodes may be of the same type or different types. The film thickness of the metal electrode 16 is not particularly limited, but from the viewpoint of increasing transparency, it is preferably about 10 nm. If transparency is not required, considering durability, it is preferably 40 nm or more, and more preferably 100 nm or more.

[0145] The method for forming the transparent electrode 12 and the metal electrode 16 is not particularly limited, but they can be formed by, for example, a dry process such as vacuum deposition or sputtering; or a wet process using conductive ink or the like.

[0146] There are no particular restrictions on the components and manufacturing methods when a hole transport layer 13 and an electron transport layer 15 are provided, and known technologies can be used. For example, components and manufacturing methods described in public documents such as International Publication No. 2013 / 171517, International Publication No. 2013 / 180230, or Japanese Patent Publication No. 2012-191194 can be used.

[0147] The photoelectric conversion layer 14 is a layer that absorbs light and separates electric charges. The photoelectric conversion layer 14 of the photoelectric conversion element of the present invention is a layer containing the compound (1) of the present invention described above. More specifically, it is the film of the present invention described above. The photoelectric conversion layer 14 can be formed, for example, by applying the above-described composition of the present invention onto a layer that will be beneath the photoelectric conversion layer 14, such as the hole transport layer 13, and then drying it.

[0148] The photoelectric conversion element 10 can be obtained, for example, by forming a transparent electrode 12, a hole transport layer 13, a photoelectric conversion layer 14, an electron transport layer 15, and a metal electrode 16 on a transparent substrate 11 in this order.

[0149] The photoelectric conversion element of the present invention has a photoelectric conversion layer 14 containing compound (1), which allows for the absorption wavelength to be extended while suppressing dark current, and thus provides high sensor sensitivity on the longer wavelength side.

[0150] [CMOS image sensor] The CMOS image sensor of the present invention comprises the photoelectric conversion element of the present invention described above. The structure of the CMOS image sensor can adopt the structure of a known CMOS image sensor. For example, one can refer to the description in Japanese Patent Publication No. 2021-57422, and is not particularly limited. More specifically, an example of a CMOS image sensor is one in which metal wiring, the photoelectric conversion element of the present invention, a color filter, and a microlens are stacked in this order on a substrate such as a silicon substrate. [Examples]

[0151] The present invention will be described in more detail below with reference to examples, but the following examples are not intended to limit the scope of the present invention.

[0152] [Synthesis of compound (6a-2a-3)] Compound (G-1) shown below was synthesized using the same method as described in the publicly available document (International Publication No. 2024 / 181311). 0.50 g (0.57 mmol) of the obtained compound (G-1) and 0.42 g (1.25 mmol) of tributyl(1,3-dioxolan-2-ylmethyl)phosphonium bromide were placed in a reaction vessel and added to 32.4 mL of anhydrous tetrahydrofuran under a nitrogen atmosphere. After cooling the reaction solution to 0°C, 0.069 g (1.71 mmol, 60% oil dispersion) of sodium hydride was added and the mixture was stirred for 30 minutes. After stirring overnight at room temperature, the mixture was cooled again to 0°C, 6.5 mL of dilute hydrochloric acid was added dropwise, and the mixture was stirred at room temperature for 4 hours. The organic layer was extracted with chloroform and water, the extract was dried over sodium sulfate, and the solvent was removed from the solution after removing the solids by filtration. The obtained crude product was purified by silica gel chromatography to obtain 0.47 g of the solid compound (yield 89%). 1H-NMR analysis confirmed that the obtained compound was compound (J-1). The 1H-NMR measurement data is shown below. 1H-NMR (400MHz, solvent: CDCl3, ppm): δ9.60(d,2H), 7.43(d,2H), 7.16(m,2H), 7.03(s,2H), 6.43(dd,2H), 4.22 (q,2H), 1.68-1.94(m,12H), 1.29-1.57(m,12H), 0.88-1.05(m,28H), 0.69-0.74(m,8H), 0.61-0.65(m,6H)

[0153] [ka]

[0154] Separately, the compound (I-1) of the following formula was synthesized by the method described in Japanese Patent Application Laid-Open No. 2023-500815. Next, 0.155 g (0.17 mmol) of the obtained compound (J-1) and 0.109 g (0.45 mmol) of the compound (I-1) were placed in a reaction vessel, 3.6 mL of toluene and 7.2 mL of ethanol were added and dissolved, and then 0.104 g (0.55 mmol) of p-toluenesulfonic acid monohydrate was added, and the mixture was stirred at room temperature for 3 hours. The organic layer was extracted with chloroform and water, the extract was dried over sodium sulfate, and the solvent of the solution from which the solid content was removed by filtration was distilled off to obtain a solid. The obtained crude product was purified using silica gel chromatography to obtain 0.17 g of a solid compound (yield 74%). By 1H-NMR analysis, it was confirmed that the obtained compound was the compound (6a-2a-3). The measurement data of 1H-NMR are shown below. 1H-NMR (400 MHz, solvent: CDCl3, ppm): δ 8.73 (s, 2H), 8.40 - 8.55 (m, 4H), 7.90 (s, 2H), 7.43 (d, 2H), 7.34 (s, 2H), 7.12 (s, 2H), 4.32 (q, 2H), 1.72 - 2.00 (m, 12H), 1.35 - 1.58 (m, 12H), 0.91 - 1.09 (m, 28H), 0.64 - 0.74 (m, 14H)

[0155]

Chemical formula

[0156] [Synthesis of compound (6a-2a-2c-1)] The compound (B-2) of the following formula was synthesized by the same method as described in the known literature (New J.Chem., 2020, Vol. 44, p. 8032.). Using the obtained compound (B-2), the compound (C-2) of the following formula was synthesized by the same method as described in the known literature (J.Mater.Chem.A, 2020, Vol. 8, p. 5163.).

[0157] For compound (B-2) 1 The measurement data of 1H-NMR are shown below. 1H-NMR (400MHz, solvent: CDCl3, ppm): δ7.15(dd,1H), 6.73(dd,1H), 6.22(dd,1H), 4.22(sext,1H), 1.71-1.58(m,1H), 1.50-1.20(m,10H), 0.89(t,3H)

[0158] Compound (C-2) 1 The H-NMR measurement data is shown below. 1 H-NMR (400MHz, solvent: CDCl3, ppm): δ9.81(s,1H), 7.39(d,1H), 6.73(m,1H), 4.22(sext,1H), 1.76-1.69(m,1H), 1.61-1.29(m,10H), 0.89(t,3H)

[0159] [ka]

[0160] Next, 2.92 g (12.9 mmol) of compound (C-2) was dissolved in 25 mL of acetonitrile. 2.41 g (13.5 mmol) of N-bromosuccinimide was slowly added. After stirring at room temperature for 1 hour, water and hexane were added, and the organic layer was washed three times with water. After drying over anhydrous sodium sulfate, the compound was purified by silica gel chromatography to obtain the compound (99% yield). 1 1H-NMR analysis confirmed that the obtained compound was compound (D-2). 1 The H-NMR measurement data is shown below. 1 H-NMR (400MHz, solvent: CDCl3, ppm): δ9.71(s,1H), 7.34(s,1H), 4.27(sext,1H), 1.80-1.71(m,1H), 1.64-1.30(m,10H), 0.90(t,3H)

[0161] [ka]

[0162] Separately, the compound (F-1) shown below was synthesized by the method described in a publicly available document (Macromolecules, 2007, Vol. 40, p. 1981). Next, referring to the method described in Japanese Patent Publication No. 2022-030124, 4.29 g (5.93 mmol) of compound (F-1) and 3.71 g (12.2 mmol) of compound (D-2) were reacted. After removing the solvent under reduced pressure, the mixture was purified by silica gel column chromatography to obtain the compound (yield 93%). 1 1H-NMR analysis confirmed that the obtained compound was compound (G-2). 1 The H-NMR measurement data is shown below. 1 H-NMR (400MHz, solvent: CDCl3, ppm): δ9.75(s,2H), 7.43(s,2H), 7.29(s,2H), 4.45(sext ,2H), 1.95-1.85(m,6H), 1.77-1.68(m,2H), 1.61-0.92(m,42H), 0.71-0.60(m,12H)

[0163] [ka]

[0164] Next, 0.53 g (0.63 mmol) of compound (G-2) and 0.26 g (0.71 mmol) of tributyl(1,3-dioxolan-2-ylmethyl)phosphonium bromide were placed in a reaction vessel and added to 30 mL of anhydrous tetrahydrofuran under a nitrogen atmosphere. After cooling the reaction solution to 0°C, 0.037 g (0.92 mmol, 60% oil dispersion) of sodium hydride was added and the mixture was stirred for 30 minutes. After stirring overnight at room temperature, the mixture was cooled again to 0°C, 3.5 mL of dilute hydrochloric acid was added dropwise, and the mixture was stirred at room temperature for 4.5 hours. The organic layer was extracted with chloroform and water, the extract was dried over sodium sulfate, and the solvent was removed from the solution after removing the solids by filtration. The resulting crude product was purified using silica gel chromatography to obtain 0.22 g of the compound as a solid (yield 40%). ¹H-NMR analysis confirmed that the obtained compound was compound (J-2). The ¹H-NMR measurement data is shown below. 1H-NMR (400MHz, solvent: CDCl3, ppm): δ9.75(s,1H), 9.60(d,1H), 7.41-7.42(m,2H), 7.29(s,1H), 7.16(d,1H), 7.05(s,1H), 6.44(dd,1H ), 4.37-4.48(m,2H), 1.85-1.95(m,6H), 1.67-1.77(m,2H), 1.35-1.58(m,18H), 0.91-0.99(m,22H), 0.71-0.80(m,8H), 0.63(t,6H).

[0165] [ka]

[0166] 0.22 g (0.25 mmol) of compound (J-2) and 0.18 g (0.74 mmol) of compound (I-1) were placed in a reaction vessel, dissolved in 3.5 mL of toluene and 7.0 mL of ethanol, and then 0.21 g (1.1 mmol) of p-toluenesulfonic acid monohydrate was added, and the mixture was stirred at room temperature for 3.5 hours. The organic layer was extracted with chloroform and water, and the extract was dried over sodium sulfate. After removing the solids by filtration, the solvent was removed from the solution to obtain a solid. The resulting crude product was purified using silica gel chromatography to obtain 0.27 g of the compound as a solid (yield 82%).

[0167] ¹H-NMR analysis confirmed that the obtained compound was compound (6a-2a-2c-1). The ¹H-NMR measurement data is shown below. ¹H-NMR (400 MHz, solvent: CDCl3, ppm): δ 8.75 (s, ¹H), 8.73 (s, ¹H), 8.68 (s, ¹H), 8.50-8.57 (m, ¹H), 8.43 (d, ¹H), 7.91 (s, ¹H), 7.90 (s, ¹H), 7.60-7.62 (m, ¹H), 7.42-7.50 (m, ¹H) H), 7.33(m,1H), 7.14(m,1H), 4.56(q,1H), 4.50(q,1H), 1.92-2.03(m,6H), 1.72-1. 83(m,2H), 1.45-1.60(m,10H), 1.39(m,8H), 0.94-1.02(m,22H), 0.63-0.75(m,14H)

[0168] [ka]

[0169] [Synthesis of comparative compound (N-1)] 0.044 g (0.047 mmol) of compound (J-1) and 0.030 g (0.011 mmol) of compound (I-1) were placed in a reaction vessel, 1.95 mL of chloroform was added and stirred to dissolve, then 0.05 mL of pyridine was added and the mixture was stirred at room temperature for 3 hours. The solvent was removed by distillation, and the resulting crude product was purified by silica gel chromatography to obtain 0.028 g of the solid compound (yield 42%). ¹H-NMR analysis confirmed that the obtained compound was compound (N-1). The ¹H-NMR measurement data is shown below. 1H-NMR (400MHz, solvent: CDCl3, ppm): δ8.74(s,2H), 8.41-8.56(m,4H), 7.90(s,2H), 7.43(d,2H), 7.33(s,2H), 7.12(m,2H), 4.32(q,2H), 1.72-2.01(m,12H), 1.34-1.57(m,12H), 0.90-1.09(m,28H), 0.64-0.75(m,14H).

[0170] [ka]

[0171] [Synthesis of comparative compound (N-2)] Compound (I-2) shown below was synthesized separately using the same method as described in a publicly available document (Adv. Mater., 2017, Vol. 29, p. 1703080). 0.22 g (0.25 mmol) of compound (G-1) and 0.16 g (0.59 mmol) of compound (I-2) were placed in a reaction vessel, 6.2 mL of chloroform was added and stirred to dissolve, then 0.25 mL of pyridine was added and the mixture was stirred at 60°C for 3 hours. After cooling, the solvent was removed by distillation, and the resulting crude product was purified by silica gel chromatography to obtain 0.29 g of the solid compound (yield 86%). ¹H-NMR analysis confirmed that the obtained compound was compound (4-3o-50). The ¹H-NMR measurement data is shown below. 1H-NMR (400MHz, solvent: CDCl3, ppm): δ8.74(s,2H), 8.70(s,2H), 7.92(s,2H), 7.61-7.62(m,2H), 7.50(br.s.,2H), 4.41-4 .44(quin,2H), 1.75-2.03(m,12H), 1.43-1.60(br.s.,4H), 1.34-1.37(m,8H), 0.89-1.10(m,28H), 0.63-0.74(m,14H).

[0172] [ka]

[0173] [Synthesis of comparative compound (N-3)] The comparative compound (N-3) was synthesized using the method described in WO2024 / 181311.

[0174] [ka]

[0175] [Example 1] <Absorption Spectrum Measurement> Weigh 1.11 mg of compound (6a-2a-3), dissolve it in 500 mL of spectroscopic chloroform, and then measure 1.60 × 10⁻⁶. -6 A solution of M was prepared. The obtained solution was placed in an absorption cell, and the absorption spectrum was measured using a UV-Vis-Near-Infrared spectrophotometer (manufactured by JASCO Corporation, product name "V-770"). The maximum absorption wavelength was identified from the obtained spectrum, and the HOMO-LUMO gap (meV) was calculated. The results are shown in Table 1. The values ​​shown in Table 1 are relative to the HOMO-LUMO gap of compound (N-2) used in Comparative Example 2 described later. The HOMO-LUMO gap can be considered as the energy value of the electron transition from HOMO to LUMO. Therefore, the smaller the HOMO-LUMO gap is compared to the reference value, i.e., the larger the negative value, the more the HOMO-LUMO gap is decreasing, and the longer the absorption wavelength is being observed.

[0176] [Example 2] A solution of the same concentration as in Example 1 was prepared, and the same measurements and results were analyzed, except that compound (6a-2a-2c-1) was used.

[0177] [Comparative Examples 1-3] Solutions of the same concentrations as in Example 1 were prepared, except for the use of compounds (N-1) to (N-3), and the same measurements and results were analyzed.

[0178] <Evaluation of HOMO levels by theoretical calculation> The following compounds were used as model compounds for Examples 1-2 and Comparative Examples 1-3. The HOMO levels of each model compound were calculated and evaluated based on the theoretical calculations shown below.

[0179] [ka]

[0180] [Measurement and Evaluation Methods] (Calculation of HOMO levels) We used Wavefunction's Spartan '20 software for molecular orbital calculations to theoretically determine the HOMO levels of each model compound. The B3LYP / 6-31G(d) method was adopted for calculating the HOMO levels. The HOMO level of the model compound (N-2) was used as the reference value. These results are shown in Table 1.

[0181] [Table 1]

[0182] Table 1 shows that in the compounds of Examples 1 and 2, which have a diene structure and a cyano group, the absorption wavelength was significantly longer and the HOMO level was greatly reduced. On the other hand, in the compound of Comparative Example 1, which has a diene structure but lacks a cyano group, a shift in the absorption wavelength to a longer wavelength was observed, but the HOMO level rose. Furthermore, in the compound of Comparative Example 3, which has a cyano group but lacks a diene structure, the HOMO level fell, but no shift in the absorption wavelength to a longer wavelength was observed. These results demonstrate that compound (1) of the present invention has the effect of increasing the absorption wavelength while also having a deep HOMO level.

[0183] [Example 3] <Manufacturing of photoelectric conversion elements> (Formation of hole transport layer) The surface of an ITO substrate, on which a transparent conductive film of indium tin oxide (ITO) was patterned as a transparent electrode on a glass substrate, was treated with ozone for 10 minutes using an ultraviolet ozone cleaning machine (manufactured by Japan Laser Electronics Co., Ltd., product name "NL-UV253"). Separately, 60 mg of a polytriarylamine compound (hole transport polymer) represented by the following formula (H-1) was dissolved in 1 mL of anisole to prepare a composition for forming a hole transport layer. A hole transport layer-forming composition was spin-coated onto a transparent electrode of an ozone-treated ITO substrate at a rotation speed of 1000 rpm for 60 seconds, and then heated and dried at 240°C for 30 minutes to form a hole transport layer with a thickness of 300 nm.

[0184] [ka]

[0185] (Formation of the photoelectric conversion layer) As the p-type semiconductor material, a compound represented by the following formula (P-1) (weight-average molecular weight 80,000) was used. Compound (6a-2a-3) was used as the n-type semiconductor material. An active layer-forming composition, which is an organic semiconductor ink, was prepared by dissolving 0.11 g of p-type semiconductor material and 0.13 g of n-type semiconductor material in 9.68 mL of o-xylene. In the active layer-forming composition, the mass ratio of the n-type semiconductor material to the p-type semiconductor material (n-type semiconductor material / p-type semiconductor material) was 1.2. The solid content concentration of the active layer-forming composition was 25 mg / mL. Using the obtained active layer-forming composition, the hole transport layer was spin-coated at 1000 rpm per minute, followed by heat treatment (thermal annealing) at 120°C for 10 minutes to form a photoelectric conversion layer (active layer) consisting of an organic thin film with a thickness of 150 nm.

[0186] [ka]

[0187] (Formation of electron transport layer and metal electrode) A 40 nm thick electron transport layer was formed on a photoelectric conversion layer by depositing C60 fullerene (manufactured by Frontier Carbon Co., Ltd.) as an electron transport material in a vacuum. Next, aluminum was deposited in a vacuum as a metal electrode material on the electron transport layer to form a 100 nm thick metal electrode, thereby obtaining a photoelectric conversion element. The obtained photoelectric conversion elements were evaluated as follows.

[0188] <Rating> (Evaluation of external quantum efficiency (EQE)) The photoelectric conversion element was irradiated with a xenon lamp under a -5V applied voltage, and the external quantum efficiency at a wavelength of 1250 nm was measured using an action spectrum measuring device (Pexel Technologies, Inc., product name "PEC-S20"). Table 2 shows the results of the external quantum efficiency at a wavelength of 1250 nm. The values ​​shown in Table 2 are relative values ​​(relative EQE values) when the external quantum efficiency at a wavelength of 1250 nm obtained in Comparative Example 4, described later, is set to 1.0.

[0189] (Measurement of dark current) The dark current was measured when -5V was applied using a photoelectric conversion element. A high-precision current measuring device (Keithley Instruments, product name "Keithley 6482") was used to measure the dark current. The results are shown in Table 3. The values ​​shown in Table 3 are relative values ​​(relative dark current values) when the dark current in the photoelectric conversion element obtained in Comparative Example 4 described later is set to 1.0.

[0190] [Example 4] A photoelectric conversion element was manufactured in the same manner as in Example 3, except that compound (6a-2a-2c-1) was used as the n-type semiconductor material, and the external quantum efficiency and dark current were measured when -5V was applied.

[0191] [Comparative Example 4] A photoelectric conversion element was manufactured in the same manner as in Example 3, except that comparative compound (N-1) was used as the n-type semiconductor material, and the external quantum efficiency and dark current were measured when -5V was applied.

[0192] [Comparative Example 5] A photoelectric conversion element was manufactured in the same manner as in Example 3, except that comparative compound (N-2) was used as the n-type semiconductor material, and the external quantum efficiency was measured when -5V was applied. Note that dark current was not measured for Comparative Example 5.

[0193] [Comparative Example 6] A photoelectric conversion element was manufactured in the same manner as in Example 3, except that comparative compound (N-3) was used as the n-type semiconductor material, and the external quantum efficiency was measured when -5V was applied. Note that dark current was not measured for Comparative Example 6.

[0194] [Table 2]

[0195] [Table 3]

[0196] As shown in Table 2, the photoelectric conversion elements obtained in Examples 3 and 4 exhibited significantly higher sensor sensitivity with a greater EQE at 1250 nm compared to the photoelectric conversion element obtained in Comparative Example 4. Furthermore, the photoelectric conversion elements obtained in Examples 3 and 4 exhibited greater light sensitivity at longer wavelengths compared to the photoelectric conversion elements obtained in Comparative Examples 5 and 6. These results reflect the characteristic of the present invention's material having a longer absorption wavelength. The photoelectric conversion elements obtained in Examples 3 and 4 had lower dark currents compared to the photoelectric conversion element obtained in Comparative Example 4. These results reflect the characteristic of the present material having a deep HOMO level. Furthermore, since compound (6a-2a-2c) has a deeper HOMO level than compound (6a-2a-3), Example 4 had an even lower dark current than Example 3. These results demonstrate that a photoelectric conversion element using compound (1) of the present invention can achieve high sensor sensitivity in the long-wavelength region of absorption wavelengths. [Industrial applicability]

[0197] The compounds of the present invention have a deep HOMO level while extending the absorption wavelength, making them useful as semiconductor materials for photoelectric conversion elements that respond with high sensitivity to longer wavelength light. [Explanation of Symbols]

[0198] 10 Photoelectric conversion element 11 Transparent substrate 12 Transparent electrode 13 Hole transport layer 14 Photoelectric conversion layer 15 Electron transport layer 16 Metal Electrodes

Claims

1. A compound represented by the following general formula (1). A-D-A...(1) In general formula (1), A is independently a group represented by any of the following general formulas (2a) to (2d), at least one of the two A's includes the following general formula (2a) or (2b), and D is an electron-donating group consisting of 2 to 20 cyclic groups. 【Chemistry 1】 In general formulas (2a) to (2d), V １ , １ , １ to V ４ are each independently a C—R １ or a nitrogen atom, and R １ is a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom or a cyano group, provided that when V １ to V ４ is C—R １ , at least one of R １ is a cyano group. Z is an oxygen atom or a dicyanomethylene group, and Ar １ is a substituted or unsubstituted aryl group or heteroaryl group.

2. The compound according to claim 1, wherein the two A's in the general formula (1) are the same and are selected from the general formula (2a) or (2b).

3. The compound according to claim 1, wherein the two A's in the general formula (1) are different, and the combination of the two A's is the combination of general formulas (2a) and (2c), or the combination of general formulas (2b) and (2d).

4. The compound according to claim 1, wherein in the general formula (1), A is the following general formula (2a') or (2c'). 【Chemistry 2】

5. The compound according to claim 1, wherein in the general formula (1), A is the following general formula (2b') or (2d'). 【Transformation 3】 In general formulas (2b') and (2d'), R ２ Each of these is independently a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, or a cyano group.

6. The compound according to claim 1, wherein D in the general formula (1) is a group represented by any of the following general formulas (3) to (5). 【Chemistry 4】 In general formulas (3) to (5), W is C - (R ３ ) ２ , Si-(R ３ ) ２ , Ge-(R ３ ) ２ N-R ３ , O-C (R ３ ) ２ , or C(R ３ ) ２ -O and R ３ Each is independently an alkyl group, an optionally substituted aryl group, or an optionally substituted heteroaryl group; each is independently an optionally substituted 1- to 5-cyclic heteroaryl group containing an aryl group, a cyclopentadienyl group, or an oxygen atom, a sulfur atom, a nitrogen atom, a silicon atom, a germanium atom, or a selenium atom; G is a heteroaryl ring containing a nitrogen atom; s is an integer from 0 to 1; and t is an integer from 0 to 3.

7. In the above general formulas (3) to (5), -(E) ｔ The compound according to claim 6, wherein - is an aryl group or heteroaryl group consisting of 3 to 5 fused rings selected from substituted thiophene, furan, selenofen, thienothiophene, bithiophene, or terthiophene, or substituted benzene, thiophene, furan, selenofen, cyclopentadiene, silole, and pyrrole, J and K are each independently a substituted phenyl group, furan, thiophene, selenofen, or thienothiophene, L is a heteroaryl group consisting of 1 to 3 fused rings selected from substituted phenyl group, naphthyl group, thiophene, thienothiophene, or benzene, thiophene, furan, selenofen, cyclopentadiene, silole, and pyrrole, and G is thiadiazole, selenadiazole, triazole, benzoquinoxaline, or diphenylpyrazine.

8. The compound according to claim 1, wherein D in the general formula (1) is represented by the following general formula (6). 【Transformation 5】 In general formula (6), Q １ Each of these is independently an oxygen atom, a sulfur atom, a selenium atom, and N-R ３ or CR ３ =CR ３ And Ar ２ Each of these is independently an alkyl group, an aryl group, or a heteroaryl group, and Ar ３ Each of these is independently either an aryl group or a heteroaryl group, or Ar ３ It is not necessary to have Y. １ ~Y ４ Each of the elements is independently a hydrogen atom, an alkyl group, an alkoxy group, or an ester group, and each of the elements a and b independently represents an integer between 1 and 3.

9. In the above general formula (6), Q １ is an oxygen atom or a sulfur atom, and two Ar ３ The compound according to claim 8, wherein the total number of rings is 0 to 3.

10. In the above general formula (6), Y １ and Y ３ One of them is a hydrogen atom, and the other is an alkyl group, an alkoxy group, or an ester group, Y ２ and Y ４ The compound according to claim 9, wherein one of the atoms is a hydrogen atom and the other is an alkyl group, an alkoxy group, or an ester group.

11. In the above general formula (6), Y １ and Y ２ The compound according to claim 8, wherein each of them is an independently branched alkoxy group at position 1.

12. A composition containing the compound described in any one of claims 1 to 11.

13. A film containing the compound described in any one of claims 1 to 11.

14. A photoelectric conversion element comprising the film described in claim 13.

15. A CMOS image sensor comprising the photoelectric conversion element described in claim 14.

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