Indolylmethyleneindandione derivatives, production method and photoelectric conversion element

Abstract

To provide a compound showing absorption property suitable as a photoelectric conversion material for blue light; a method for synthesizing easily the compound; and a photoelectric conversion element containing the compound.SOLUTION: There is provided an indolylmethylene indanedione derivative showing absorption maximum in a wavelength region of 400-500 nm, shown by following formula (1).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an indolyl methylene indandione derivative and a method for producing the same. [Background technology]

[0002] Photoelectric conversion elements are used in sensors such as optical sensors and image sensors, and in photovoltaic devices such as solar cells. A photoelectric conversion element using an organic photoelectric conversion material is disclosed in Patent Document 1 and the like.

[0003] As photoelectric conversion elements, elements using silicon semiconductors are widely used, and silicon photodiodes are mainly used as imaging elements. Since such silicon photodiodes have sensitivity over the entire visible light range, a color filter with RGB arranged in a mosaic pattern is placed on top of the photodiode, and each pixel is assigned as a light receiving section for each RGB, thereby performing color imaging. In this method, the efficiency of light utilization is low due to the loss of incident light in the color filter, and it is feared that this will become a barrier to increasing the sensitivity of imaging elements. Therefore, an imaging element in which organic photoelectric conversion layers of each color of RGB are stacked (hereinafter referred to as a stacked organic imaging element) has been proposed (see, for example, Non-Patent Document 1). In this method, there is no light loss due to the color filter compared to when a color filter is used, and the efficiency of light utilization is several times higher, so it is expected to be used in high-sensitivity devices that have an advantage in miniaturizing pixels accompanying the high pixel count of devices such as cameras.

[0004] The photoelectric conversion layer of the stacked organic imaging element is required to have high light absorption and wavelength selectivity suitable for the color of each RGB layer. In the case of the B layer (blue photoelectric conversion layer), it is preferable that the B layer shows maximum absorption in the blue light region of 400 to 500 nm and has small absorption in the green light region (i.e., 500 to 600 nm) and the red light region (i.e., 600 to 700 nm), and a material showing such absorption characteristics is required.

[0005] Patent Document 2 describes a photoelectric conversion element containing an indolylmethylene indandione derivative, but it differs from the indolylmethylene indandione derivative of the present invention in that it has a diarylamino group on the indolyl group. It is described that the compound described in this document has a maximum absorption wavelength of 510 nm or more and 600 nm or less, and also differs from the indolylmethylene indandione derivative of the present invention in that it shows a maximum absorption in the green light region.

[0006] Patent Document 3 describes an indolyl methylene indanedione derivative as a photoelectric conversion material, but it differs from the indolyl methylene indanedione derivative of the present invention in that it has an acidic group.

[0007] Patent Documents 4 to 6 disclose photoelectric conversion elements containing perylene derivatives, coumarin derivatives, dipyrromethene derivatives, and the like, but all of them are different from the photoelectric conversion element containing the indolylmethyleneindanedione derivative of the present invention. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Patent No. 4148374 [Patent Document 2] WO2014-051007A1 [Patent Document 3] JP2005-19756 Public Relations [Patent Document 4] WO2020-195935A1 [Patent Document 5] WO2020-196029A1 [Patent Document 6] WO2021-029223A1 [Non-patent literature]

[0009] [Non-Patent Document 1] Japanese Journal of Applied Physics, 2011, Vol. 50, p. 024103 Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention aims to provide a compound that exhibits absorption characteristics suitable for use as a blue light photoelectric conversion material, i.e., that exhibits maximum absorption in the wavelength region of 400 to 500 nm, a method for simply synthesizing the compound, and a photoelectric conversion element containing the compound. [Means for solving the problem]

[0011] As a result of extensive research aimed at solving the above problems, the inventors discovered that a novel indolyl methylene indanedione derivative exhibits maximum absorption in the wavelength range of 400 to 500 nm and has excellent wavelength selectivity, thereby completing the present invention.

[0012] That is, the present invention is [1] An indolylmethyleneindanedione derivative represented by formula (1):

[0013] [ka]

[0014] In formula (1), R 1 R represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a haloalkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 14 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a heteroaromatic group having 3 to 18 carbon atoms, or a trialkylsilylalkyl group having 4 to 7 carbon atoms, and the aryl group, aralkyl group, and heteroaromatic group may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom. 2 and R 3each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, a haloalkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroaromatic group having 3 to 18 carbon atoms, and the aryl group and the heteroaromatic group may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom. 2 and R 3 R may combine with each other to form an alkylene group having 2 to 6 carbon atoms. 4 , R 5 and R 6 R each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroaromatic group having 3 to 18 carbon atoms, and the aryl group and the heteroaromatic group may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom. 7 R represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or an aryl group having 6 to 14 carbon atoms. 8 , R 9 , R 10 , R 11 , R 12 and R 13 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroaromatic group having 3 to 18 carbon atoms, and the aryl group and the heteroaromatic group may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom. 2 ~R 13 cannot all be hydrogen atoms. n represents an integer from 0 to 3. [2] R 1is an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroaromatic group having 3 to 18 carbon atoms, and the aryl group and the heteroaromatic group are optionally substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom; [3] R 2 and R 3 is a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or an aryl group having 6 to 14 carbon atoms, and the aryl group may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom; [4] R 4 , R 5 、 R 6 and R 7 is a hydrogen atom; [5] R 8 , R 9 , R 10 , R 11 , R 12 and R 13 The indolyl methylene indanedione derivative according to any one of the above [1] to [4], wherein is a hydrogen atom, and n is 0 or 1. [6] Formula (2)

[0015] [ka]

[0016] (In the formula, R 1R represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a haloalkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 14 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a heteroaromatic group having 3 to 18 carbon atoms, or a trialkylsilylalkyl group having 4 to 7 carbon atoms, and the aryl group, aralkyl group, and heteroaromatic group may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom. 2 and R 3 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, a haloalkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroaromatic group having 3 to 18 carbon atoms, and the aryl group and the heteroaromatic group may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom. 2 and R 3 R may combine with each other to form an alkylene group having 2 to 6 carbon atoms. 4 , R 5 and R 6 R each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroaromatic group having 3 to 18 carbon atoms, and the aryl group and the heteroaromatic group may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom. 7 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or an aryl group having 6 to 14 carbon atoms. 2 ~R 7 cannot be a hydrogen atom at the same time.) and a 5-carboxyindole derivative represented by formula (3)

[0017] [ka]

[0018] (In the formula, R 8 , R 9 , R10 , R 11 , R 12 and R 13 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroaromatic group having 3 to 18 carbon atoms, and the aryl group and the heteroaromatic group may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom. n represents an integer of 0 to 3.

[0019] [ka]

[0020] (In the formula, R 1 ~R 13 and n are as defined above.) [7] A method for producing an indolylmethylene indandione derivative according to [6], characterized in that a 5-carboxyindole derivative is reacted with a 1,3-indandione derivative in the presence of an acid. [8] A method for producing an indolylmethylene indandione derivative according to [6], characterized in that a 5-carboxyindole derivative is reacted with a 1,3-indandione derivative in the presence of a base. [9] A photoelectric conversion element comprising the indolylmethyleneindanedione derivative according to any one of [1] to [5] above;

[10] A photoelectric conversion element comprising the indolyl methylene indanedione derivative according to any one of [1] to [5] above in a photoelectric conversion layer;

[11] The photoelectric conversion element according to

[10] above, wherein the photoelectric conversion layer further contains a fullerene derivative;

[12] Fullerene derivative C60 Or C 70 The photoelectric conversion element according to the above item

[11] ,

[0021] The present invention will be described in detail below.

[0022] R in the indolyl methylene indandione derivative (1) of the present invention 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12 , R 13 The definition of and n will be explained.

[0023] R 1 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a haloalkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 14 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a heteroaromatic group having 3 to 18 carbon atoms, or a trialkylsilylalkyl group having 4 to 7 carbon atoms, and the aryl group, aralkyl group, and heteroaromatic group are optionally substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom.

[0024] R 1The alkyl group having 1 to 8 carbon atoms represented by the formula (I) may be any of a linear, branched, or cyclic alkyl group, and specific examples thereof include a methyl group, a cyclohexylmethyl group, an ethyl group, a 2-cyclopentylethyl group, a propyl group, a 2-methylpropyl group, a 2,2-dimethylpropyl group, a 3-cyclopropylpropyl group, an isopropyl group, a cyclopropyl group, a butyl group, a 2-methylbutyl group, a 3-methylbutyl group, a 2-butyl group, a 3-methylbutan-2-yl group, a tert-butyl group, a cyclobutyl group, a pentyl group, 2-methylpentyl group, 3-ethylpentyl group, 2,4-dimethylpentyl group, 2-pentyl group, 2-methylpentan-2-yl group, 4,4-dimethylpentan-2-yl group, 3-pentyl group, 3-ethylpentan-3-yl group, cyclopentyl group, 2,5-dimethylcyclopentyl group, 3-ethylcyclopentyl group, hexyl group, 2-methylhexyl group, 3,3-dimethylhexyl group, 4-ethylhexyl group, 2-hexyl group, 2-methylhexan-2-yl group, 5,5-dimethyl Examples of the aryl group include hexane-2-yl, 3-hexyl, 2,4-dimethylhexane-3-yl, cyclohexyl, 4-ethylcyclohexyl, 4,4-dimethylcyclohexyl, heptyl, 2-heptyl, 3-heptyl, 4-heptyl, bicyclo[2.2.1]heptyl, octyl, 2-octyl, 3-octyl, 4-octyl, cyclooctyl, and bicyclo[2.2.2]octyl groups. In terms of ease of synthesis, a methyl group, an ethyl group, a propyl group, a 2-methylpropyl group, a 2,2-dimethylpropyl group, an isopropyl group, a butyl group, a 2-butyl group, a tert-butyl group, a pentyl group, a 2-pentyl group, a 3-pentyl group, a cyclopentyl group, a hexyl group, a 2-hexyl group, a 3-hexyl group, or a cyclohexyl group is preferred, and a methyl group, an ethyl group, a propyl group, a 2-methylpropyl group, an isopropyl group, a tert-butyl group, a cyclopentyl group, or a cyclohexyl group is more preferred.

[0025] R 1The haloalkyl group having 1 to 4 carbon atoms represented by the formula (I) may be any of a linear, branched, or cyclic haloalkyl group, and specific examples thereof include a trifluoromethyl group, a difluoromethyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1-difluoroethyl group, a 2,2-difluoroethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a 2,2,3,3-tetrafluoropropyl group, a 3,3,3-trifluoropropyl group, a 1,1-difluoropropyl group, a perfluoroisopropyl group, a 2,2,2-trifluoro-1-(trifluoro-1-fluoro-2- ... Examples of such a group include a fluoroalkyl group, a perfluorocyclopropyl group, a 2,2,3,3-tetrafluorocyclopropyl group, a perfluorobutyl group, a 2,2,3,3,4,4,4-heptafluorobutyl group, a 3,3,4,4,4-pentafluorobutyl group, a 4,4,4-trifluorobutyl group, a chloromethyl group, a bromomethyl group, an iodomethyl group, a 2-chloroethyl group, and a 3-bromopropyl group. From the viewpoint of ease of synthesis of the indolylmethyleneindanedione derivative (1), a fluoroalkyl group is preferred, and a 2,2,2-trifluoroethyl group is more preferred.

[0026] R 1The aryl group having 6 to 14 carbon atoms represented by the formula (I) is not particularly limited, and specific examples thereof include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 2-biphenylyl group, a 3-biphenylyl group, a 4-biphenylyl group, a 3,5-terphenylyl group, a 1-anthryl group, a 2-anthryl group, a 9-anthryl group, a 1-phenanthrenyl group, a 2-phenanthrenyl group, a 3-phenanthrenyl group, a 4-phenanthrenyl group, a 9-phenanthrenyl group, a 1-fluorenyl group, a 2-fluorenyl group, a 3-fluorenyl group, a 4-fluorenyl group, a 9,9-diphenyl group, a 2-phenyl group, a 3-phenyl group, a 4- ...2-phenyl group, a 3-phenyl group, a 4-phenyl group, a 2-phenyl group, a 2-phenyl group, a 3-phenyl group, a 4-phenyl group, a 2-phenyl group, a 2-phenyl group, a 2-phenyl group, a 2-phenyl group, a 2-phenyl group, a 2-phenyl group, a 2-phenyl group, a 2-phenyl group, a 2-phenyl group, a 2-phenyl group, a 2-phenyl group, a 2-phenyl group, a 2 Examples include methyl-9H-fluoren-1-yl group, 9,9-dimethyl-9H-fluoren-2-yl group, 9,9-dimethyl-9H-fluoren-3-yl group, 9,9-dimethyl-9H-fluoren-4-yl group, 1-pyrenyl group, 2-pyrenyl group, 9-pyrenyl group, 1-triphenylenyl group, and 2-triphenylenyl group, and from the viewpoint of ease of synthesis of the indolylmethyleneindanedione derivative (1), a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 2-biphenylyl group, a 3-biphenylyl group, and a 4-biphenylyl group are preferred.

[0027] R 1The aryl group having 6 to 14 carbon atoms and represented by the formula (I) may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom. The alkyl group having 1 to 4 carbon atoms may be any of a linear, branched, or cyclic alkyl group, and specific examples thereof include a methyl group, an ethyl group, a propyl group, a 2-methylpropyl group, an isopropyl group, a cyclopropyl group, a butyl group, a 2-butyl group, a tert-butyl group, and a cyclobutyl group. A methyl group is preferred in terms of ease of synthesis of the indolylmethyleneindanedione derivative (1). As the dialkylamino group having 2 to 5 carbon atoms, the two alkyl groups may be either linear or branched, and the two alkyl groups may be combined to form a ring, and specific examples thereof include dimethylamino, diethylamino, 1-pyrrolidinyl, and 1-piperidinyl groups, with dimethylamino or 1-pyrrolidinyl being preferred in terms of ease of synthesis of the indolylmethyleneindandione derivative (1). As the diarylamino group having 12 to 18 carbon atoms, the two aryl groups may be combined to form a ring, and specific examples thereof include diphenylamino, 1-naphthyl(phenyl)amino, 2-naphthyl(phenyl)amino, and 9-carbazoyl groups, and with diphenylamino or 9-carbazoyl being preferred in terms of ease of synthesis of the indolylmethyleneindandione derivative (1). Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, with a fluorine atom being preferred in terms of ease of synthesis of the indolylmethyleneindanedione derivative (1).

[0028] R 1 Specific examples of the aralkyl group having 7 to 12 carbon atoms represented by the following formula include a phenylmethyl group and a phenylethyl group, and the phenylmethyl group is preferred in terms of ease of synthesis of the indolylmethyleneindanedione derivative (1).

[0029] R 1The heteroaromatic group having 3 to 18 carbon atoms represented by the formula (I) is not particularly limited, and specific examples thereof include a 2-furanyl group, a 3-furanyl group, a 2-thienyl group, a 3-thienyl group, a 1-pyrrolyl group, a 2-pyrrolyl group, a 3-pyrrolyl group, a 2-pyridyl group, a 3-pyridyl group, a 4-pyridyl group, a 2-quinolyl group, a 3-quinolyl group, a 4-quinolyl group, a 5-quinolyl group, a 6-quinolyl group, a 7-quinolyl group, an 8-quinolyl group, a 2-benzofuranyl group, a 3-benzofuranyl group, a 2-benzothienyl group, a 3-benzothienyl group, a 1-indolyl group, a 2-indolyl group, a 3-indolyl group, a 1-carbazoyl group, a 2-carbazoyl group, a 3-carbazoyl group, a 4-carbazoyl group, a 9-phenyl-9H- Examples include a carbazol-1-yl group, a 9-phenyl-9H-carbazol-2-yl group, a 9-phenyl-9H-carbazol-3-yl group, a 9-phenyl-9H-carbazol-4-yl group, a dibenzofuran-2-yl group, a dibenzofuran-3-yl group, a dibenzofuran-4-yl group, a dibenzothiophen-2-yl group, a dibenzothiophen-3-yl group, and a dibenzothiophen-4-yl group. From the viewpoint of ease of synthesis of the indolyl methylene indandione derivative (1), a 2-pyridyl group, a 3-pyridyl group, a 4-pyridyl group, a 2-quinolyl group, a 3-quinolyl group, a 4-quinolyl group, a 5-quinolyl group, a 6-quinolyl group, a 7-quinolyl group, or an 8-quinolyl group is preferred.

[0030] R 1The heteroaromatic group having 3 to 18 carbon atoms and represented by the formula (I) may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom. The alkyl group having 1 to 4 carbon atoms may be any of linear, branched, and cyclic alkyl groups, and specific examples thereof include a methyl group, an ethyl group, a propyl group, a 2-methylpropyl group, an isopropyl group, a cyclopropyl group, a butyl group, a 2-butyl group, a tert-butyl group, and a cyclobutyl group. A methyl group is preferred in terms of ease of synthesis of the indolylmethyleneindanedione derivative (1). As the dialkylamino group having 2 to 5 carbon atoms, the two alkyl groups may be either linear or branched, and the two alkyl groups may be combined to form a ring, and specific examples thereof include dimethylamino, diethylamino, 1-pyrrolidinyl, and 1-piperidinyl groups, with dimethylamino or 1-pyrrolidinyl being preferred in terms of ease of synthesis of the indolylmethyleneindandione derivative (1). As the diarylamino group having 12 to 18 carbon atoms, the two aryl groups may be combined to form a ring, and specific examples thereof include diphenylamino, 1-naphthyl(phenyl)amino, 2-naphthyl(phenyl)amino, and 9-carbazoyl groups, and with diphenylamino or 9-carbazoyl being preferred in terms of ease of synthesis of the indolylmethyleneindandione derivative (1). Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, with a fluorine atom being preferred in terms of ease of synthesis of the indolylmethyleneindanedione derivative (1).

[0031] R 1 The trialkylsilylalkyl group having 4 to 7 carbon atoms represented by the formula (I) is not particularly limited, and specific examples thereof include a trimethylsilylmethyl group, a triethylsilylmethyl group, a dimethyl-tert-butylsilylmethyl group, a bis(trimethylsilyl)methyl group, and the like. In terms of ease of synthesis of the indolylmethyleneindanedione derivative (1), a trimethylsilylmethyl group is preferred.

[0032] R 1 is more preferably an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroaromatic group having 3 to 18 carbon atoms, and the aryl group and heteroaromatic group may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms and a halogen atom, and is most preferably an alkyl group having 1 to 8 carbon atoms.

[0033] R 2 and R 3 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, a haloalkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroaromatic group having 3 to 18 carbon atoms, and the aryl group and the heteroaromatic group may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom. 2 and R 3 may combine with each other to form an alkylene group having 2 to 6 carbon atoms.

[0034] R 2 and R 3 Examples of the halogen atom represented by the formula (I) include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. A fluorine atom is preferred in that the indolylmethyleneindanedione derivative (1) has excellent absorption properties.

[0035] R 2 and R 3 As the alkyl group having 1 to 8 carbon atoms represented by the formula: 1 Examples of the alkyl group having 1 to 8 carbon atoms are the same as those exemplified in the alkyl group having 1 to 8 carbon atoms, and a methyl group is preferred in terms of ease of synthesis of the indolyl methylene indanedione derivative (1). 2 and R 3 may be bonded together to form an alkylene group having 2 to 6 carbon atoms, specifically, R 2 and R 3Examples of the ring include a cyclobutene ring, a cyclopentene ring, a cyclohexene ring, a cycloheptene ring, and a cyclooctene ring, each of which contains a double bond between carbon atoms to which the rings are bonded. In terms of ease of synthesis of the indolyl methylene indanedione derivative (1), a cyclopentene ring and a cyclohexene ring are preferred.

[0036] R 2 and R 3The haloalkyl group having 1 to 8 carbon atoms represented by the formula (I) may be any of a linear, branched, or cyclic haloalkyl group, and specific examples thereof include a trifluoromethyl group, a difluoromethyl group, a perfluoroethyl group, a 2,2,2-trifluoroethyl group, a 1,1-difluoroethyl group, a 2,2-difluoroethyl group, a perfluoropropyl group, a 2,2,3,3,3-pentafluoropropyl group, a 2,2,3,3-tetrafluoropropyl group, a 3,3,3-trifluoropropyl group, a 1,1-difluoropropyl group, a perfluoroisopropyl group, a 2,2,2-trifluoro- 1-(trifluoromethyl)ethyl group, perfluorocyclopropyl group, 2,2,3,3-tetrafluorocyclopropyl group, perfluorobutyl group, 2,2,3,3,4,4,4-heptafluorobutyl group, 3,3,4,4,4-pentafluorobutyl group, 4,4,4-trifluorobutyl group, 1,2,2,3,3,3-hexafluoro-1-(trifluoromethyl)propyl group, 1-(trifluoromethyl)propyl group, 1-methyl-3,3,3-trifluoropropyl group, perfluorocyclobutyl group, 2,2,3,3,4,4-hexafluoro perfluorocyclobutyl group, perfluoropentyl group, 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, 3,3,4,4,5,5,5-heptafluoropentyl group, 4,4,5,5,5-pentafluoropentyl group, 5,5,5-trifluoropentyl group, 1,2,2,3,3,3-hexafluoro-1-(perfluoroethyl)propyl group, 2,2,3,3,3-pentafluoro-1-(perfluoroethyl)propyl group, perfluorocyclopentyl group, perfluorohexyl group, 2,2,3,3,4,4,5,5,6,6,6-undecyl group, Examples of the fluorohexyl group include a fluorohexyl group, a 3,3,4,4,5,5,6,6,6-nonafluorohexyl group, a 4,4,5,5,6,6,6-heptafluorohexyl group, a 5,5,6,6,6-pentafluorohexyl group, a 6,6,6-trifluorohexyl group, a perfluorocyclohexyl group, a chloromethyl group, a bromomethyl group, an iodomethyl group, a 2-chloroethyl group, and a 3-bromopropyl group. From the viewpoint of ease of synthesis of the indolylmethyleneindanedione derivative (1), a trifluoromethyl group or a 2,2,2-trifluoroethyl group is preferred.

[0037] R 2 and R 3 The aryl group having 6 to 14 carbon atoms represented by R 1 Examples of the aryl group include the same aryl groups having 6 to 14 carbon atoms as those exemplified in 1., and a phenyl group is preferred in terms of ease of synthesis of the indolylmethyleneindanedione derivative (1).

[0038] R 2 and R 3 The heteroaromatic group having 3 to 18 carbon atoms represented by R 1 Examples of the heteroaromatic groups having 3 to 18 carbon atoms are the same as those exemplified in the above, and a 2-pyridyl group, a 3-pyridyl group, or a 4-pyridyl group is preferred in terms of ease of synthesis of the indolylmethyleneindanedione derivative (1).

[0039] R 2 and R 3 is more preferably a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or an aryl group having 6 to 14 carbon atoms, the aryl group being optionally substituted with one or more of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom, and is most preferably a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.

[0040] R 4 , R 5 and R 6 each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroaromatic group having 3 to 18 carbon atoms, and the aryl group and the heteroaromatic group are optionally substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom.

[0041] R 4 , R 5 and R 6 The alkyl group having 1 to 8 carbon atoms represented by R 1Examples of the alkyl group include the same alkyl groups having 1 to 8 carbon atoms as those exemplified in 1., and a methyl group is preferred in terms of ease of synthesis of the indolylmethyleneindanedione derivative (1).

[0042] R 4 , R 5 and R 6 The aryl group having 6 to 14 carbon atoms represented by R 1 Examples of the aryl group include the same aryl groups having 6 to 14 carbon atoms as those exemplified in 1., and a phenyl group is preferred in terms of ease of synthesis of the indolylmethyleneindanedione derivative (1).

[0043] R 4 , R 5 and R 6 The heteroaromatic group having 3 to 18 carbon atoms represented by R 1 Among these, a 2-pyridyl group, a 3-pyridyl group, or a 4-pyridyl group is preferred in terms of ease of synthesis of the indolylmethyleneindanedione derivative (1).

[0044] R 4 , R 5 and R 6 As the alkyl group, a hydrogen atom is more preferable in terms of ease of synthesis.

[0045] R 7 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or an aryl group having 6 to 14 carbon atoms.

[0046] R 7 The alkyl group having 1 to 8 carbon atoms represented by R 1 Examples of the alkyl group include the same alkyl groups having 1 to 8 carbon atoms as those exemplified in 1., and a methyl group is preferred in terms of ease of synthesis of the indolylmethyleneindanedione derivative (1).

[0047] R 7 The aryl group having 6 to 14 carbon atoms represented by R 1Examples of the aryl group include the same aryl groups having 6 to 14 carbon atoms as those exemplified in 1., and a phenyl group is preferred in terms of ease of synthesis of the indolylmethyleneindanedione derivative (1).

[0048] R 7 As the alkyl group, a hydrogen atom is more preferable in terms of ease of synthesis.

[0049] R 8 , R 9 , R 10 , R 11 , R 12 and R 13 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroaromatic group having 3 to 18 carbon atoms, and the aryl group and the heteroaromatic group are optionally substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom.

[0050] R 8 , R 9 , R 10 , R 11 , R 12 and R 13 The halogen atom represented by R 2 and R 3 The halogen atoms are the same as those exemplified in the above, and a fluorine atom and a chlorine atom are preferred in terms of ease of synthesis of the indolyl methylene indanedione derivative (1).

[0051] R 8 , R 9 , R 10 , R 11 , R 12 and R 13The alkyl group having 1 to 4 carbon atoms represented by the formula (I) may be any of a linear, branched, or cyclic alkyl group. Specific examples thereof include a methyl group, an ethyl group, a propyl group, a 2-methylpropyl group, an isopropyl group, a cyclopropyl group, a butyl group, a 2-butyl group, a tert-butyl group, and a cyclobutyl group. Of these, a methyl group is preferred in terms of ease of synthesis of the indolylmethyleneindanedione derivative (1).

[0052] R 8 , R 9 , R 10 , R 11 , R 12 and R 13 The aryl group having 6 to 14 carbon atoms represented by R 1 Examples of the aryl group include the same aryl groups having 6 to 14 carbon atoms as those exemplified in 1., and a phenyl group is preferred in terms of ease of synthesis of the indolylmethyleneindanedione derivative (1).

[0053] R 8 , R 9 , R 10 , R 11 , R 12 and R 13 The heteroaromatic group having 3 to 18 carbon atoms represented by R 1 Examples of the heteroaromatic group having 3 to 18 carbon atoms include those similar to those exemplified in the above 1. In terms of excellent absorption properties of the indolylmethyleneindanedione derivative (1), a 2-pyridyl group, a 3-pyridyl group, a 4-pyridyl group, a 2-quinolyl group, a 3-quinolyl group, a 4-quinolyl group, a 5-quinolyl group, a 6-quinolyl group, a 7-quinolyl group, or an 8-quinolyl group is preferred.

[0054] R 8 , R 9 , R 10 , R 11 , R 12 and R 13 is more preferably a hydrogen atom.

[0055] In addition, R 2 ~R 13 We have given specific examples for each of the above, but 2 ~R 13but cannot simultaneously be a hydrogen atom.

[0056] n represents an integer of 0 to 3. In terms of ease of synthesis of the indolylmethyleneindanedione derivative (1), n ​​is preferably an integer of 0 to 2, and more preferably 0 or 1.

[0057] The indolyl methylene indandione derivative (1) of the present invention is not particularly limited, and specific examples thereof include the compounds having the structures shown in 1-1 to 1-74 below.

[0058] [ka]

[0059] [ka]

[0060] [ka]

[0061] [ka]

[0062] [ka]

[0063] In this specification, Me represents a methyl group.

[0064] Among the compounds represented by 1-1 to 1-74, the indolyl methylene indandione derivative (1) of the present invention is preferably a compound represented by 1-1, 1-2, 1-3, 1-4, 1-5, 1-8, 1-9, 1-10, 1-11, 1-13, 1-31, 1-37, 1-38, 1-47, 1-48 or 1-60 in terms of ease of synthesis, and more preferably a compound represented by 1-1 or 1-2.

[0065] Next, a method for producing the indolylmethyleneindanedione derivative (1) of the present invention (hereinafter referred to as the production method of the present invention) will be described.

[0066] The indolylmethyleneindanedione derivative (1) of the present invention can be produced by step 1 shown in the following reaction scheme.

[0067] [ka]

[0068] (In the formula, R 1 R represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a haloalkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 14 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a heteroaromatic group having 3 to 18 carbon atoms, or a trialkylsilylalkyl group having 4 to 7 carbon atoms, and the aryl group, aralkyl group, and heteroaromatic group may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom. 2 and R 3 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, a haloalkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroaromatic group having 3 to 18 carbon atoms, and the aryl group and the heteroaromatic group may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom. 2 and R 3 R may combine with each other to form an alkylene group having 2 to 6 carbon atoms. 4 , R 5 and R 6R each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroaromatic group having 3 to 18 carbon atoms, and the aryl group and the heteroaromatic group may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom. 7 R represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or an aryl group having 6 to 14 carbon atoms. 8 , R 9 , R 10 , R 11 , R 12 and R 13 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroaromatic group having 3 to 18 carbon atoms, and the aryl group and the heteroaromatic group may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms and a halogen atom. 2 ~R 13 cannot all be hydrogen atoms. n represents an integer from 0 to 3.) Step 1 is a step for producing the indolylmethyleneindanedione derivative (1) of the present invention by reacting a 5-carboxyindole derivative (2) with a 1,3-indanedione derivative (3).

[0069] The substituent in the 5-carboxyindole derivative (2) used in step 1 can be the same as the substituent in the indolyl methylene indandione derivative represented by formula (1), and is preferably R 1 ,R 2 , R 3 , R 4 , R 5 , R 6 and R 7 As for R 1is preferably an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 14 carbon atoms, or a heteroaromatic group having 3 to 18 carbon atoms, and the aryl group and the heteroaromatic group may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a dialkylamino group having 2 to 5 carbon atoms, a diarylamino group having 12 to 18 carbon atoms, and a halogen atom. 2 and R 3 is preferably a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or an aryl group having 6 to 14 carbon atoms, and the aryl group may be substituted with one or more substituents selected from the group consisting of an alkyl group having 1 to 4 carbon atoms and a halogen atom. 4 , R 5 、 R 6 and R 7 is preferably a hydrogen atom.

[0070] Specific examples of the 5-carboxyindole derivative (2) used in step 1 include compounds having the structures shown in the following 2-1 to 2-66.

[0071] [ka]

[0072] [ka]

[0073] [ka]

[0074] [ka]

[0075] Among the compounds represented by 2-1 to 2-66, the compounds represented by 2-1, 2-2, 2-3, 2-4, 2-7, 2-8, 2-9, 2-10, 2-12, 2-30, 2-37, 2-38, 2-47, 2-48, 2-49, 2-50, 2-51, or 2-52 are preferred in terms of ease of synthesis, and the compounds represented by 2-1, 2-2, 2-7, 2-8, 2-9, 2-10, 2-37, 2-38, 2-47, 2-48, 2-51, or 2-52 are more preferred. The 5-carboxyindole derivative (2) can be produced by a general method well known to those skilled in the art, for example, according to the method disclosed in Journal of the American Chemical Society, 2008, Vol. 130, pp. 2926-2927 or Chemistry - A European Journal, 2013, Vol. 19, pp. 15093-15096. Alternatively, a commercially available product may be used.

[0076] The substituents in the 1,3-indandione derivative (3) used in step 1 can be the same as those in the indolyl methylene indandione derivative represented by formula (1). 8 , R 9 , R 10 , R 11 , R 12 and R 13 is preferably a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group or a phenyl group, and more preferably a hydrogen atom; n is preferably 0 to 2, and more preferably 0 or 1.

[0077] Specific examples of the 1,3-indandione derivative (3) used in step 1 include compounds having the structures shown in the following 3-1 to 3-21.

[0078] [ka]

[0079] Among the compounds represented by 3-1 to 3-21, the compounds represented by 3-1, 3-2, 3-3, 3-4, 3-7 or 3-13 are preferred in terms of ease of synthesis, and the compounds represented by 3-1 or 3-2 are more preferred. The 1,3-indane derivative (3) can be produced by a general method well known to those skilled in the art, for example, according to the method disclosed in Helvetica Chimica Acta, 2019, Vol. 102, p. e1900229 or Dyes and Pigments, 2020, Vol. 175, p. 108182, etc. Commercially available products may also be used.

[0080] The molar ratio of the 5-carboxyindole derivative (2) to the 1,3-indandione derivative (3) used in step 1 is not particularly limited. In terms of good yield, the molar ratio of the 5-carboxyindole derivative (2):1,3-indandione derivative (3) is preferably in the range of 10:1 to 1:10, and more preferably in the range of 2:1 to 1:2 in terms of good reaction yield.

[0081] Step 1 can be carried out in a solvent. There is no particular limitation on the solvent that can be used, and any solvent that does not inhibit the reaction can be used. Specific examples of such solvents include ethers such as diisopropyl ether, dibutyl ether, cyclopentyl methyl ether (CPME), tetrahydrofuran (THF), 2-methyltetrahydrofuran, 1,4-dioxane, and dimethoxyethane; aromatic hydrocarbons such as benzene, toluene, xylene, mesitylene, and tetralin; aliphatic hydrocarbons such as pentane, hexane, heptane, octane, and cyclohexane; carbonates such as ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, and 4-fluoroethylene carbonate; ethyl acetate, butyl acetate, methyl propionate, and ethyl propionate. Examples of the solvent include esters such as methyl butyrate, γ-lactone, etc.; amides such as N,N-dimethylformamide (DMF), dimethylacetamide (DMAc), N-methylpyrrolidone (NMP), etc.; ureas such as N,N,N',N'-tetramethylurea (TMU), N,N'-dimethylpropyleneurea (DMPU), etc.; dimethylsulfoxide (DMSO); and alcohols such as methanol, ethanol, isopropyl alcohol, butanol, octanol, benzyl alcohol, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, 2,2,2-trifluoroethanol, etc., which may be mixed in any ratio. There is no particular limit to the amount of the solvent used. In terms of the good reaction yield of the indolyl methylene indandione derivative (1) of the present invention, aliphatic hydrocarbons or alcohols are preferred, and octane or ethanol is more preferred.

[0082] The reaction of step 1 can be promoted by carrying out the reaction in the presence of an acid. The acid to be used is not particularly limited, and may be either an inorganic acid or an organic acid. Examples of the inorganic acid include hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoric acid, nitric acid, etc., and examples of the organic acid include carboxylic acids such as acetic acid, propionic acid, benzoic acid, etc., and sulfonic acids such as p-toluenesulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, etc. Hydrochloric acid, sulfuric acid, or p-toluenesulfonic acid is preferred, and p-toluenesulfonic acid is more preferred, in terms of the good reaction yield of the indolylmethyleneindanedione derivative (1) of the present invention.

[0083] The molar equivalent of the acid used in step 1 is not particularly limited, and in terms of good yield, the molar ratio of the 1,3-indandione derivative (3) to the acid is preferably in the range of 100:1 to 1:100, and in terms of good reaction yield, it is more preferably in the range of 10:1 to 1:10. The reaction in step 1 can be promoted by carrying out the reaction in the presence of a base. The base used is not particularly limited, and may be either an inorganic base or an organic base. Examples of the inorganic base include metal hydroxides such as sodium hydroxide, potassium hydroxide, calcium hydroxide, etc.; metal carbonates such as sodium carbonate, potassium carbonate, lithium carbonate, cesium carbonate, etc.; metal acetates such as potassium acetate, sodium acetate, etc.; metal phosphates such as potassium phosphate, sodium phosphate, etc.; metal hydrides such as sodium hydride, potassium hydride, calcium hydride, etc.; metal alkyl oxides such as sodium methoxide, potassium methoxide, sodium ethoxide, potassium isopropyl oxide, potassium tert-butoxide, etc.; and examples of the organic base include tertiary alkyl amines such as trimethylamine, triethylamine, diisopropylethylamine, tributylamine, etc.; cyclic azines such as pyridine, pyrazine, quinoline, etc.; and secondary cyclic amines such as pyrrolidine, piperidine, piperazine, N-methylpiperazine, morpholine, etc. In terms of the good reaction yield of the indolylmethyleneindanedione derivative (1) of the present invention, an organic base such as triethylamine, piperidine, piperazine or N-methylpiperazine is preferred, and piperidine or N-methylpiperazine is more preferred.

[0084] The molar equivalent of the base used in step 1 is not particularly limited, and the molar ratio of the 1,3-indandione derivative (3) to the base is preferably in the range of 500:1 to 1:100 in terms of a good yield, and more preferably in the range of 100:1 to 1:10 in terms of a good reaction yield. The reaction temperature when carrying out step 1 is not particularly limited, and can usually be carried out at a temperature appropriately selected from -80 to 200°C, and is preferably carried out at a temperature appropriately selected from 0°C to 150°C in terms of a good reaction yield of the indolyl methylene indandione derivative (1) of the present invention, and more preferably carried out at a temperature appropriately selected from 10°C to 140°C.

[0085] The indolyl methylene indanedione derivative (1) of the present invention can be obtained by carrying out a normal treatment after completion of the reaction in step 1. If necessary, it may be purified by recrystallization, column chromatography, sublimation, preparative HPLC, or the like.

[0086] Further, a photoelectric conversion element containing the indolyl methylene indandione derivative (1) of the present invention (hereinafter referred to as "the photoelectric conversion element of the present invention") will be described. The photoelectric conversion element of the present invention includes a substrate, a negative electrode layer, a photoelectric conversion layer, and a positive electrode layer. If necessary, a hole transport layer and / or an electron injection blocking layer may be provided between the negative electrode layer and the photoelectric conversion layer, and an electron transport layer and / or a hole injection blocking layer may be provided between the positive electrode layer and the photoelectric conversion layer.

[0087] In the photoelectric conversion element of the present invention, the indolyl methylene indanedione derivative (1) of the present invention may be used in any layer, but is preferably used in the photoelectric conversion layer. The photoelectric conversion layer may contain a dopant. The dopant may be

[60] fullerene (C 60 ),

[70] Fullerene (C 70 ), Phenyl-C 61 -Methyl butyrate (

[60] PCBM), phenyl-C 71 -Methyl butyrate (

[70] PCBM), phenyl-C 85Examples of fullerene derivatives include

[60] fullerene (C 60 ) or

[70] fullerene (C 70 ) is preferred.

[0088] In the photoelectric conversion element of the present invention, a hole transport layer may be provided between the negative electrode and the photoelectric conversion layer, and an electron transport layer may be provided between the positive electrode and the photoelectric conversion layer, in order to improve carrier transport. The hole transport layer has either hole injection or transport, or electron barrier properties, and may be either an organic or inorganic material. Specifically, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline-based copolymers, and conductive polymer oligomers can be mentioned, and in particular, poly(3,4-ethylenedioxythiophene):polystyrenesulfonic acid (PEDOT:PSS) can be exemplified. The electron transport layer is not particularly limited, and is preferably one that has high electron injection efficiency and efficiently transports injected electrons. Specific examples of the electron transport layer include nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenylidene methane derivatives, anthraquinodimethane, and anthrone derivatives or oxadiazole derivatives. In addition, for the purpose of suppressing the generation of dark current, an electron injection blocking layer may be provided between the negative electrode and the photoelectric conversion layer, and a hole injection blocking layer may be provided between the positive electrode and the photoelectric conversion layer. Examples of the electron injection blocking layer include triarylamines such as 2,7-bis(9-carbazolyl)-9,9-spirobifluorene (Spiro-2CBP). Examples of the hole injection blocking layer include naphthalene tetracarboxylic acid diimides such as N,N'-di(4-pyridyl)-1,4,5,8-naphthalene tetracarboxylic acid diimide, tris(8-quinolinolato)aluminum (Alq 3The hole transport layer may also function as the electron injection blocking layer, and the electron transport layer may also function as the hole injection blocking layer.

[0089] There is no particular limitation on the method for producing the photoelectric conversion layer, hole transport layer, electron transport layer, hole injection blocking layer and electron injection blocking layer (hereinafter referred to as "organic layers") of the photoelectric conversion element of the present invention, but film formation by vacuum deposition is possible. Film formation by vacuum deposition can be performed by using a general-purpose vacuum deposition device. The degree of vacuum in the vacuum chamber when forming a film by vacuum deposition is 1×10, which can be achieved by a commonly used diffusion pump, turbomolecular pump, cryopump, etc., taking into consideration the production takt time and production costs for producing organic electroluminescent devices. -2 ~1×10 -5 The deposition rate is preferably about 0.005 to 1.0 nm / sec, depending on the thickness of the film to be formed. Film formation can also be performed by a spin coating method, an inkjet method, a casting method, a dipping method, or the like using a general-purpose device.

[0090] The positive electrode layer and the negative electrode layer of the photoelectric conversion element of the present invention are connected to a power source via an electrical conductor such as a conducting wire. Either the positive electrode layer or the negative electrode layer can be in contact with the substrate of the photoelectric conversion element of the present invention. For convenience, the electrode in contact with the substrate is called the lower electrode. In the photoelectric conversion element of the present invention, either the positive electrode layer or the negative electrode layer may be the lower electrode.

[0091] As for the positive electrode layer and the negative electrode layer (hereinafter referred to as "electrode") of the photoelectric conversion element of the present invention, at least one of them, which is the light receiving surface, is preferably light transmissive. As the light transmissive electrode, a general transparent electrode material can be used, and examples thereof include metal oxides such as indium-tin oxide (ITO), indium-zinc oxide (IZO), tin oxide, aluminum or indium-doped tin oxide, magnesium-indium oxide, or nickel-tungsten oxide, metal nitrides such as gallium nitride, metal selenides such as zinc selenide, or metal sulfides such as zinc sulfide. Metal oxides are preferred in terms of good light transmissivity and electrical conductivity, and ITO, IZO, and tin oxide are more preferred. In addition, the electrode can be modified with plasma-deposited fluorocarbon.

[0092] For the other electrode that is not the light receiving surface, in addition to the transparent electrode materials exemplified above, an opaque or reflective electrode material can be used. Examples of the opaque or reflective electrode material include gold, silver, iridium, molybdenum, palladium, platinum, sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum, and aluminum / aluminum oxide (Al 2 O 3 ) mixtures, indium, lithium / aluminum mixtures, rare earth metals, etc.

[0093] There is no particular limitation on the method for producing the electrodes of the photoelectric conversion element of the present invention, but film formation by vacuum deposition, sputtering, electron beam deposition, chemical reaction methods (such as the sol-gel method), coating methods, etc. are possible.

[0094] The photoelectric conversion element of the present invention is formed on a substrate. The substrate may be light-transmitting or opaque depending on the intended light receiving direction. Light-transmitting is preferable for receiving light through the substrate, and examples of the substrate include transparent glass, quartz, and plastic. Examples of opaque substrates include silicon and silicon oxide. The substrate may also be a composite structure including multiple material layers.

[0095] The method for producing the photoelectric conversion element of the present invention is not particularly limited, but the element can be produced by successively forming an electrode layer, an organic layer, and an electrode layer on a substrate. Alternatively, an organic layer and an electrode layer may be successively formed on a substrate on which an electrode layer has been formed in advance. Effect of the Invention

[0096] INDUSTRIAL APPLICABILITY The indolyl methylene indanedione derivative (1) of the present invention has a maximum absorption in the blue light region and has photoelectric conversion ability, and is therefore expected to be used as an organic electronic material, such as a blue light organic photoelectric conversion element. EXAMPLES

[0097] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention should not be construed as being limited to these. [ 1 H-NMR measurement] 1 For H-NMR measurements, a Bruker ASCEND 400 (400 MHz; manufactured by BRUKER) was used. 1 H-NMR was performed using deuterated chloroform (CDCl 3 ) was used as the measurement solvent, and tetramethylsilane (TMS) was used as the internal standard. [Thin film preparation, photoelectric conversion element preparation and film thickness measurement] The thin film and photoelectric conversion element were prepared by vacuum deposition using EROLA-500 (ULVAC KIKOU Co., Ltd.). The substrate was washed with a neutral detergent and pure water, dried, and then cleaned with oxygen plasma. The film thickness was measured using a stylus film thickness gauge DektakXT (BRUKER). [Absorption spectrum measurement] The absorption spectrum was measured using a spectrophotometer V-750 (manufactured by JASCO Corporation). The measurement was performed at a scan speed of 400 nm / min. The measurement sample was a thin film prepared on a quartz substrate by vacuum deposition. [External quantum efficiency measurement] The external quantum efficiency was measured using a solar cell spectral response measurement device (manufactured by Soma Optical Co., Ltd.). The irradiated light intensity was 50 μW / cm 2 Measurements were performed.

[0098] The reagents used were commercially available.

[0099] Synthesis Example 1

[0100] [ka]

[0101] 5-Bromo-3-methyl-1H-indole (5.0g, 24mmol) was dissolved in dimethylformamide (100mL), sodium hydride (1.4g, 36mmol) was added in an ice bath, and the mixture was stirred for 30 minutes. Isobutyl bromide (3.9g, 29mmol) was added and the mixture was stirred at room temperature for 16 hours. Water was added to this solution to stop the reaction, and the mixture was extracted with hexane. The extract was dried over magnesium sulfate, and low boiling points were distilled off under reduced pressure to obtain 5-bromo-1-isobutyl-3-methyl-1H-indole (5.3g, 83%). 1 H-NMR (CDCl 3 ):δ7.67(d,J=2.0Hz,1H),7.24(dd,J=8.8,2.0Hz,1H),7.14(d,J=8.8Hz,1H),6.84(d,J=1 .2Hz,1H),3.81(d,J=7.2Hz,2H),2.28(d,J=1.2Hz,3H),2.14(m,1H)0.90(d,J=7.2Hz,6H).

[0102] Synthesis Example 2

[0103] [ka]

[0104] 5-Bromo-1-isobutyl-3-methyl-1H-indole (3.0g, 11mmol) obtained in Synthesis Example-1 was dissolved in THF (50mL), and 1.55M n-butyllithium / hexane solution (14mL, 22mmol) was added at -78°C and stirred for 1 hour, then dimethylformamide (4.3mL, 55mmol) was added and stirred for 2 hours while warming to room temperature. Water was added to this solution to stop the reaction, and the solution was extracted with hexane. The extract was dried with magnesium sulfate, and low boiling points were distilled off under reduced pressure to obtain 1-isobutyl-3-methyl-1H-indole-5-carbaldehyde (2.3g, 96%). 1 H-NMR (CDCl 3 ):δ10.03(s,1H),8.81(d,J=1.6Hz,1H),7.75(dd,J=8.8,1.6Hz,1H),7.35(d,J=8.8Hz,1H),6.93 (d,J=0.8Hz,1H),3.88(d,J=7.2Hz,2H),2.37(d,J=0.8Hz,3H),2.17(m,1H)0.93(d,J=7.2Hz,6H).

[0105] Synthesis Example 1

[0106] [ka]

[0107] 1-Isobutyl-3-methyl-1H-indole-5-carbaldehyde (2.3 g, 11 mmol) and 1,3-indandione (1.6 g, 11 mmol) obtained in Synthesis Example 2 were suspended in ethanol (50 mL) and stirred at room temperature for 16 hours. The precipitated solid was collected by filtration and washed with ethanol and hexane to obtain a yellow solid of 2-[(1-isobutyl-3-methyl-1H-indol-5-yl)methylene]-1,3-indandione (0.96 g, 25%). 1 H-NMR (CDCl 3):δ8.94(d,J=1.6Hz,1H),8.47(dd,J=8.8,1.6Hz,1H),8.10(s,1H),8.03-7.95(m,2H),7.80-7.74(m,2H),7.36(d,J =8.8Hz,1H),6.91(d,J=1.2Hz,1H),3.89(d,J=7.2Hz,2H),2.42(d,J=1.2Hz,3H),2.19(m,1H)0.94(d,J=7.2Hz,6H).

[0108] Synthesis Example 2

[0109] [ka]

[0110] 1-Isobutyl-3-methyl-1H-indole-5-carbaldehyde (1.9 g, 8.6 mmol) and 1,3-benzoindandione (1.7 g, 8.6 mmol) obtained in Synthesis Example 2 were suspended in ethanol (50 mL) and stirred at room temperature for 72 hours. The precipitated solid was collected by filtration, washed with ethanol and hexane, extracted with chloroform, and washed with 1N-NaOH solution. The resulting extract was dried over magnesium sulfate, and the low boiling point was distilled off under reduced pressure to obtain a solid, which was dissolved in hot ethanol and allowed to stand at room temperature to obtain 2-[(1-isobutyl-3-methyl-1H-indol-5-yl)methylene]-1,3-benzoindandione (1.2 g, 35%) as an orange solid. 1 H-NMR (CDCl 3 ):δ9.06(d,J=1.6Hz,1H),8.55(dd,J=8.8,1.6Hz,1H),8.50(s,1H),8.49(s,1H),8.20(s,1H),8.12-8.06(m,2H),7.71-7.65(m,2 H),7.38(d,J=8.8Hz,1H),6.92(d,J=0.8Hz,1H),3.90(d,J=7.2Hz,2H),2.44(d,J=0.8Hz,3H),2.20(m,1H)0.95(d,J=7.2Hz,6H).

[0111] Evaluation example-1~2 A thin film of the indolyl methylene indandione derivative of the present invention was prepared on a quartz substrate by vacuum deposition, and the absorption spectrum of the thin film was measured. The maximum absorption wavelength, the absorption coefficient at the maximum absorption wavelength, and the half width are shown in Table 1. In this specification, the half width means the full width at half maximum.

[0112] Comparative Example 1 A thin film of Coumarin 6 described in Patent Document 4 was prepared on a quartz substrate by vacuum deposition, and the absorption spectrum of the thin film was measured. The maximum absorption wavelength, and the absorption coefficient and half-width at the maximum absorption wavelength are shown in Table 1.

[0113] [Table 1]

[0114] From Evaluation Examples 1 and 2, it was found that the indolyl methylene indanedione derivative of the present invention exhibits a maximum absorption wavelength in the range of 400 to 500 nm, which is the blue light region, and exhibits an absorption coefficient and a narrow half-width equivalent to those of Coumarin 6 shown in Comparative Example 1. The fact that it exhibits a narrow half-width is advantageous in terms of improving wavelength selectivity when applied to a stacked organic imaging element.

[0115] Evaluation Examples 1-2 A photoelectric conversion element containing the indolyl methylene indandione derivative of the present invention as a constituent component was produced, and its performance was evaluated.

[0116] The substrate used was a glass substrate with an ITO transparent electrode on which a 2 mm wide ITO film was patterned in a stripe shape. This substrate was washed with a neutral detergent and pure water, dried, and then oxygen plasma cleaned. On the washed substrate, 2,7-bis(carbazol-9-yl)-9,9-spirobifluorene (Spiro-2CBP, film thickness 30 nm) was applied as a hole transport layer, and the indolyl methylene indandione derivative of the present invention and

[60] fullerene (C 60A co-deposited film of ITO (thickness 100 nm) and N,N'-di(4-pyridyl)-1,4,5,8-naphthalenetetracarboxylic diimide (thickness 30 nm) were then deposited as an electron transport layer by vacuum deposition. A metal mask was then placed on the deposition substrate so as to be perpendicular to the ITO stripes, and aluminum was vacuum deposited as a positive electrode layer at a deposition rate of 0.3 nm / sec. After deposition, the multilayer film was sealed in a nitrogen atmosphere glove box with oxygen and moisture concentrations of 1 ppm or less, and the light-receiving area of ​​the multilayer film was 4 mm2. 2 The photoelectric conversion element was produced using a glass sealing cap and an epoxy type UV-curable resin (manufactured by Nagase ChemteX Corporation).

[0117] The measurement results of the external quantum efficiency when the photoelectric conversion element was irradiated with light having a wavelength of 450 nm are shown in Table 2. From this, it was found that the photoelectric conversion element of the present invention operates as a photoelectric conversion element having sensitivity in the blue light region.

[0118] [Table 2] [Industrial Applicability]

[0119] INDUSTRIAL APPLICABILITY The indolyl methylene indanedione derivative (1) of the present invention can be used as an organic photodiode material, an organic thin-film solar cell material, an organic semiconductor laser material, an organic EL display material, a photonic crystal material, or other electronic material.

Claims

1. An indolylmethyleneindanedione derivative represented by formula (1): 【Chemistry 1】 In formula (1), R １ represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a haloalkyl group having 1 to 4 carbon atoms, or a trialkylsilylalkyl group having 4 to 7 carbon atoms. R 2 , R 3 , R 4 , R 5 and R 6 each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. R ７ represents a hydrogen atom. R ８ , R ９ , R １０ , R １１ , R １２ and R １３ Each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ２ ~R １３ but cannot simultaneously be a hydrogen atom. n represents an integer of 0 or 1.

2. R １ The indolylmethyleneindanedione derivative according to claim 1, wherein is an alkyl group having 1 to 8 carbon atoms.

3. R ４ , R ５ , R ６ and R ７ The indolyl methylene indanedione derivative according to any one of claims 1 to 2, wherein is a hydrogen atom.

4. R ８ , R ９ , R １０ , R １１ , R １２ and R １３ The indolyl methylene indanedione derivative according to any one of claims 1 to 3, wherein is a hydrogen atom.

5. Formula (2) 【Chemistry 2】 (In the formula, R1 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a haloalkyl group having 1 to 4 carbon atoms, or a trialkylsilylalkyl group having 4 to 7 carbon atoms. R2, R3, R4, R5, and R6 each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. R ７ represents a hydrogen atom. ２ ~R ７ and cannot be hydrogen atoms at the same time.) and a 5-carboxyindole derivative represented by formula (3) 【Chemistry 3】 (In the formula, R ８ , R ９ , R １０ , R １１ , R １２ and R １３ each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; and n represents an integer of 0 or 1. 【Chemistry 4】 (In the formula, R １ ~R １３ and n are as defined above.

6. 6. The method for producing an indolyl methylene indandione derivative according to claim 5, which comprises reacting a 5-carboxyindole derivative with a 1,3-indandione derivative in the presence of an acid.

7. 6. The method for producing an indolyl methylene indandione derivative according to claim 5, which comprises reacting a 5-carboxyindole derivative with a 1,3-indandione derivative in the presence of a base.

8. A photoelectric conversion element comprising the indolylmethyleneindanedione derivative according to claim 1 .

9. A photoelectric conversion element comprising the indolyl methylene indanedione derivative according to claim 1 in a photoelectric conversion layer.

10. The photoelectric conversion element according to claim 9 , wherein the photoelectric conversion layer further contains a fullerene derivative.

11. Fullerene derivative C ６０ Or C ７０ The photoelectric conversion element according to claim 10 .

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