Quinoid dithiophene compound, Near-infrared absorbing colorant, Film, Color filter, and Near-infrared ray cut filter

Abstract

Disclosed is a quinoid dithiophene compound having absorption in the near-infrared region, having solubility suitable for coating films, and having high light resistance, a near-infrared absorbing colorant, a thin film, a color filter, and a near-infrared cut filter. A compound represented by the following general formula (1).

Description

Technical Field

[0001] This invention relates to neoquinone-type bithiophene compounds and near-infrared absorbing pigments. Background Technology

[0002] In recent years, while there has been an increasing demand for fastness, especially lightfastness and weather resistance, and for dyes rather than pigments (functionality in film and molecular dispersion states) in pigment compounds, molecular design for adjusting various physical properties remains largely untapped. Therefore, research is underway into organic pigment compounds based on novel frameworks.

[0003] Near-infrared (NIIR) absorbing pigments are pigments that absorb light in a wavelength range longer than visible light (700 nm-2000 nm), exhibiting strong light absorption based on charge transfer in organic pigments and metal complexes. Because NIIR light is highly permeable to organisms and is abundantly contained in sunlight, various applications have been developed utilizing NIIR light, with promising prospects in a wide range of fields including photoelectric conversion elements such as organic thin-film solar cells and pigment-sensitized solar cells, neutral density (ND) filters, color filters, security applications, agricultural films, dimming filters (thermal insulation / semiconductor sensors), and photodynamic therapy.

[0004] The low lightfastness of most near-infrared absorbing pigments to date has become a problem. Furthermore, the use of near-infrared absorbing pigments in the aforementioned applications is subject to various limitations. For example, organic pigments that absorb near-infrared light using phthalocyanine, rhodamine, etc., as parent materials have been synthesized to date. However, their variety and quantity are limited, and most of them also absorb visible light (Patent Document 1), thus few are suitable for applications requiring high transparency, such as near-infrared absorbing films.

[0005] In addition, for example, when forming a film by coating a pigment solution for use as a photoelectric conversion element, the solubility of the pigment is required, and in the case of film formation, the molecular structure makes a significant contribution.

[0006] Therefore, it is desirable to develop near-infrared absorbing pigments that absorb near-infrared light with less absorption in the visible light region, have suitable solubility for coatings, high durability, and absorption in the easily handled near-infrared region.

[0007] In addition, color filters are used in near-infrared absorbing pigment liquid crystal and electroluminescent (EL) display devices, as well as CCD and CMOS imaging elements. Color filters are manufactured by laminating colored layers on light-transmitting substrates such as glass and transparent resin using dyeing, pigment dispersion, printing, and electrodeposition methods. By improving the performance of the color filter, the brightness of the light source can be reduced, enabling the display device to operate at lower voltages.

[0008] The color filters used in the past functioned as filters that only allowed the three primary colors of blue, green and red to pass through in the visible light region. However, they had weak cutoff capabilities for light in the near-infrared region, resulting in the transmission of near-infrared light.

[0009] Therefore, the following method is proposed: by using a near-infrared cutoff filter layer and a color filter layer together, the influence of near-infrared light is eliminated, and only red, green, and blue light is introduced to the pixel for photoelectric conversion. Patent Document 2 describes a method of setting an inorganic multilayer film as a near-infrared cutoff filter layer below the color filter layer.

[0010] On the other hand, from the perspective of recent advancements in lightweighting and noise reduction of solid-state imaging elements, there is a demand for thin-film near-infrared cut-off filter layers. For example, Patent Document 3 describes an optical filter layer that functions as both a color filter and a near-infrared cut-off filter by using a coloring resin composition comprising organic coloring pigments and infrared-absorbing pigments. By reducing the conventional two-layer structure to a single-layer structure, a thin-film filter is achieved.

[0011] For pigments that can be used for the above-mentioned purposes, it is desirable that they possess the following properties: optimal spectroscopic absorption; good fastness to light, moisture, and chemicals; and high solubility.

[0012] To date, bithiophene compounds obtained by crosslinking with electron-withdrawing groups have been synthesized (Non-Patent Literature 1 and Non-Patent Literature 2). However, although their absorption derived from CT has been observed in the long wavelength region, most of them are forbidden transitions and have very small absorption coefficients, which is insufficient for materials with absorption bands in the near-infrared region.

[0013] Patent Document 1: Japanese Patent Application Publication No. 2011-116717

[0014] Patent Document 2: International Publication 2014 / 041742

[0015] Patent Document 3: International Publication 2017 / 002910

[0016] Non-patent literature

[0017] Non-patent literature 1: The Journal of Physical Chemistry, 2014, Vol. 118, No. 15, pp. 7844-7855

[0018] Non-patent literature 2: Macromolecular Chemistry and Physics, 2012, Vol. 213, Vol. 12, pp. 1216-1224 Summary of the Invention

[0019] The problem to be solved by the present invention is to provide a near-infrared absorbing pigment that has absorption in the near-infrared light region, solubility suitable for coatings, and high lightfastness.

[0020] To address the aforementioned issues, the inventors, focusing on the bithiophene skeleton, conducted in-depth research into the development of novel near-infrared absorbing pigments. As a result, they discovered that the compounds of this invention are useful as near-infrared absorbing pigments for solving the aforementioned problems. In other words, this invention has the following main points.

[0021] 1. A compound represented by the following general formula (1).

[0022]

Chemistry 1

[0023]

[0024] [In the formula, R] 1 ~R 4 Each can be independent and represents a straight-chain or branched alkyl group having 1 to 20 carbon atoms that can have substituents, a straight-chain or branched alkenyl group having 2 to 20 carbon atoms that can have substituents, a straight-chain or branched alkynyl group having 2 to 20 carbon atoms that can have substituents, or a cycloalkyl group having 3 to 10 carbon atoms that can have substituents.

[0025] X 1 and X 2 This represents a separate, independent divalent group.

[0026] 2. X in the general formula (1) 1 and X 2 Compounds represented by the following general formula (2) or general formula (3).

[0027]

Chemistry 2

[0028]

[0029] [In the formula, R] 5 and R 6 Each can be independent and refers to a straight-chain or branched alkyl group with 1 to 20 carbon atoms that can have substituents, a cycloalkyl group with 3 to 10 carbon atoms that can have substituents, or an aromatic hydrocarbon group with 6 to 36 carbon atoms that can have substituents.

[0030] Y represents a carbon atom, a silicon atom, or a germanium atom.

[0031]

Transformation 3

[0032]

[0033] [In the formula, Z represents oxygen atom, CR] 7 R 8 or NR 9 ,

[0034] R 7 and R 8 Each can be represented independently as a nitrile group, an acyl group with 1 to 18 carbon atoms capable of having a substituent, or an alkoxycarbonyl group with 1 to 18 carbon atoms capable of having a substituent.

[0035] R 9 This refers to a straight-chain or branched alkyl group that can have substituents with 1 to 20 carbon atoms, a cycloalkyl group that can have substituents with 3 to 10 carbon atoms, or an aromatic hydrocarbon group that can have substituents with 6 to 36 carbon atoms.

[0036] 3. In the general formula (1), R 1 ~R 4 It is a straight-chain or branched alkyl group that can have 1 to 20 carbon atoms and can have substituents.

[0037] 4. A near-infrared absorbing pigment comprising the compound described herein.

[0038] 5. A thin film comprising the described compound.

[0039] 6. A color filter comprising the near-infrared absorbing pigment.

[0040] 7. A near-infrared cutoff filter comprising the near-infrared absorbing dye.

[0041] According to the compounds with a bithiophene skeleton disclosed in this invention, near-infrared absorbing pigments with dominant absorption characteristics in the near-infrared region, solubility suitable for coatings, and high lightfastness, as well as films based on these compounds, can be obtained. Attached Figure Description

[0042] Figure 1 This is the absorption spectrum of Example 2. Detailed Implementation

[0043] Hereinafter, embodiments of the present invention will be described in detail. The compounds of the present invention having a neo-thiophene skeleton can be used in near-infrared absorbing pigments containing the compounds, thin films, photoelectric conversion elements containing them, and color filters used in liquid crystal display devices, camera elements, etc.

[0044] Hereinafter, the compounds represented by the general formula (1) of the present invention will be specifically described, but the present invention is not limited to these compounds.

[0045] In general formula (1), R 1 ~R4 Each can be independent and can be a straight-chain or branched alkyl group having 1 to 20 carbon atoms that can have substituents, a straight-chain or branched alkenyl group having 2 to 20 carbon atoms that can have substituents, a straight-chain or branched alkynyl group having 2 to 20 carbon atoms that can have substituents, or a cycloalkyl group having 3 to 10 carbon atoms that can have substituents.

[0046] In general formula (1), as R 1 ~R 4 The phrase "a straight-chain or branched alkyl group having 1 to 20 carbon atoms that can have substituents" specifically includes, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, 2-ethylhexyl, heptyl, octyl, isooctyl, nonyl, decyl, etc.

[0047] In general formula (1), as R 1 ~R 4 The phrase "a straight-chain or branched alkenyl group with 2 to 20 carbon atoms that can have substituents" specifically includes, for example, vinyl, 1-propenyl, allyl, 1-butenyl, 2-butenyl, 1-pentenyl, 1-hexenyl, isopropenyl, isobutenyl, or alkenyl groups with 2 to 20 carbon atoms formed by bonding multiple of these alkenyl groups.

[0048] In general formula (1), as R 1 ~R 4 The phrase "cycloalkyl group with 3 to 10 carbon atoms that can have substituents" specifically includes, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclodecyl, and cyclododecyl.

[0049] In general formula (1), the "substituent" as "a straight-chain or branched alkyl group having 1 to 20 carbon atoms that can have a substituent", "a straight-chain or branched alkenyl group having 2 to 20 carbon atoms that can have a substituent", "a straight-chain or branched alkynyl group having 2 to 20 carbon atoms that can have a substituent", or "a cycloalkyl group having 3 to 10 carbon atoms that can have a substituent" can be specifically listed as follows:

[0050] Halogen atoms such as fluorine, chlorine, bromine, and iodine; cyano; hydroxyl; nitro; nitroso; carboxyl; phosphate;

[0051] Carboxylic acid ester groups such as methyl ester group and ethyl ester group;

[0052] Alkyl groups having 1 to 19 carbon atoms, including methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, 2-ethylhexyl, heptyl, octyl, isooctyl, nonyl, decyl, etc.

[0053] Alkenes with 2 to 18 carbon atoms, including vinyl, 1-propenyl, allyl, 1-butenyl, 2-butenyl, 1-pentenyl, 1-hexenyl, isopropenyl, isobutenyl, etc., are straight-chain or branched alkenyl groups.

[0054] Alkoxy groups with 1 to 20 carbon atoms, such as methoxy, ethoxy, propoxy, tert-butoxy, pentoxy, and hexoxy.

[0055] Aromatic hydrocarbon groups with 6 to 19 carbon atoms, such as phenyl, naphthyl, anthraceneyl, phenanthryl, and pyrene;

[0056] Heterocyclic groups with 5 to 19 cyclic atoms, including pyridyl, pyrimidinyl, triazinyl, thiopheneyl, furanyl (furyl group, furanyl group), pyrroloyl, imidazolyl, pyrazolyl, triazolyl, quinolinyl, isoquinolinyl, naphridyl, acridineyl, phenanthrolinel, benzofuranyl, benzothiopheneyl, oxazolyl, indolyl, carbazolyl, benzooxazolyl, thiazolyl, benzothiazolyl, quinoxalinyl, benzoimidazolyl, pyrazolyl, dibenzofuranyl, dibenzothiopheneyl, carbazolyl, etc.

[0057] Unsubstituted amino groups (-NH2), ethylamino, acetylamino, phenylamino, etc., monosubstituted amino groups, or disubstituted amino groups (diethylamino, diphenylamino, acetylphenylamino, etc.), i.e., amino groups with 0 to 20 carbon atoms;

[0058] Unsubstituted thio groups (thiols: ―SH), methylthio, ethylthio, propanethio, hex-5-en-3-thio, phenylthio, biphenylthio, etc., with 0 to 20 carbon atoms; etc.

[0059] These "substituents" may consist of only one or more, and if multiple are included, they may be the same or different from each other. Furthermore, these "substituents" may further have the substituents exemplified above.

[0060] In general formula (1), R 1 ~R 4 Preferably, it is a straight-chain or branched alkyl group that can have 1 to 20 carbon atoms and is capable of having substituents.

[0061] In general formula (1), X 1 and X 2 This indicates that the divalent groups are independent of each other.

[0062] X of general formula (1)1 and X 2 Preferably, it is represented by the general formula (2) or general formula (3).

[0063] In general formula (2), R 5 and R 6 Each can be independent and can be a straight-chain or branched alkyl group having 1 to 20 carbon atoms that can have substituents, a cycloalkyl group having 3 to 10 carbon atoms that can have substituents, or an aromatic hydrocarbon group having 6 to 36 carbon atoms that can have substituents.

[0064] In general formula (2), as R 5 and R 6 The "linear or branched alkyl group having 1 to 20 carbon atoms" in the term "linear or branched alkyl group having 1 to 20 carbon atoms capable of having substituents" can be exemplified by those in the general formula (1) represented by R. 1 ~R 4 The same group as "a straight-chain or branched alkyl group that can have 1 to 20 carbon atoms and have substituents".

[0065] In general formula (2), as R 5 and R 6 The "cycloalkyl group with 3 to 10 carbon atoms" in the phrase "cycloalkyl group capable of having substituents" can be exemplified by those represented by R in the general formula (1). 1 ~R 4 The same group is referred to as "a cycloalkyl group that can have 3 to 10 carbon atoms that are capable of having substituents".

[0066] In general formula (2), as R 5 and R 6 The phrase "aromatic hydrocarbon group with 6 to 36 carbon atoms capable of having substituents" specifically includes aryl groups such as phenyl, naphthyl, biphenyl, anthracene, phenanthryl, pyrene, benzo[a]phenanthryl, indene, and fluorene. Here, "aromatic hydrocarbon group" in this invention is synonymous with aryl, and includes fused polycyclic aromatic groups, among which phenyl, naphthyl, and biphenyl are preferred.

[0067] In general formula (2), as R 5 and R 6 The "substituent" in "a straight-chain or branched alkyl group that can have a substituent with 1 to 20 carbon atoms", "a cycloalkyl group that can have a substituent with 3 to 10 carbon atoms", or "an aromatic hydrocarbon group that can have a substituent with 6 to 36 carbon atoms" can be the same group as the "substituent" in "a straight-chain or branched alkyl group that can have a substituent with 1 to 20 carbon atoms" in general formula (1).

[0068] In general formula (2), Y represents a carbon atom, a silicon atom, or a germanium atom.

[0069] In general formula (3), Z represents oxygen atom, CR 7 R 8 or NR 9 In Z, where CR 7 R 8 or NR 9 In this case, Z has the same electronic effect as the ketone group, which is an oxygen atom.

[0070] In general formula (3), R 7 and R 8 Each can be independent and can represent a nitrile group, an acyl group having 1 to 18 carbon atoms that can have a substituent, or an alkoxycarbonyl group having 1 to 18 carbon atoms that can have a substituent.

[0071] In general formula (3), as R 7 and R 8 The "acyl group with 1 to 18 carbon atoms" in the phrase "acyl group capable of having a substituent" can specifically include: acetyl, propionyl, butyryl, isobutyryl, valeryl, isovaleryl, benzoylacetyl, benzoyl, etc. In the case of an alkyl chain, this includes cases where the hydrogen atom is partially fluorinated and cases where the hydrogen atom is completely replaced by a fluorine atom (perfluorination).

[0072] In general formula (3), as R 7 and R 8 The phrase "alkoxycarbonyl with 1 to 18 carbon atoms that can have substituents" specifically includes, for example, methoxycarbonyl and ethoxycarbonyl.

[0073] In general formula (3), R 9 It refers to a straight-chain or branched alkyl group that can have a substituent with 1 to 20 carbon atoms, a cycloalkyl group that can have a substituent with 3 to 10 carbon atoms, or an aromatic hydrocarbon group that can have a substituent with 6 to 36 carbon atoms.

[0074] In general formula (3), as R 9 The "linear or branched alkyl group having 1 to 20 carbon atoms" in the term "linear or branched alkyl group having 1 to 20 carbon atoms capable of having substituents" can be exemplified by those in the general formula (1) represented by R. 1 ~R 4 The same group as "a straight-chain or branched alkyl group that can have 1 to 20 carbon atoms and have substituents".

[0075] In general formula (3), as R 9 The "cycloalkyl group with 3 to 10 carbon atoms" in the phrase "cycloalkyl group capable of having substituents" can be exemplified by those represented by R in the general formula (1). 1 ~R 4 The same group is referred to as "a cycloalkyl group that can have 3 to 10 carbon atoms that are capable of having substituents".

[0076] In general formula (3), as R 9 The "aromatic hydrocarbon group with 6 to 36 carbon atoms" in the expression "aromatic hydrocarbon group capable of having substituents" can be listed as R in the general formula (2). 5 and R 6 The same group is referred to as "an aromatic hydrocarbon group that can have 6 to 36 carbon atoms as a substituent".

[0077] In general formula (3), as R 7 ~R 9 The "substituent" in "acyl group having 1 to 18 carbon atoms that can have a substituent", "alkoxycarbonyl group having 1 to 18 carbon atoms that can have a substituent", "linear or branched alkyl group having 1 to 20 carbon atoms that can have a substituent", "cycloalkyl group having 3 to 10 carbon atoms that can have a substituent", or "aromatic hydrocarbon group having 6 to 36 carbon atoms that can have a substituent" can be the same group as the "substituent" in "linear or branched alkyl group having 1 to 20 carbon atoms that can have a substituent" in general formula (1).

[0078] Specific examples of compounds represented by the general formula (1) of the present invention are shown below, but the present invention is not limited to these specific examples. Furthermore, the following example compounds have omitted some hydrogen atoms, carbon atoms, etc., representing one example of possible isomers, and include all other isomers. Additionally, mixtures of two or more isomers of each example compound may also be used.

[0079]

Chemistry 4

[0080]

[0081]

Transformation 5

[0082]

[0083]

Transformation 6

[0084]

[0085]

Transformation 7

[0086]

[0087]

Transformation 8

[0088]

[0089]

Chemistry 9

[0090]

[0091]

Chemistry 10

[0092]

[0093]

Chemistry 11

[0094]

[0095]

Chemistry 12

[0096]

[0097]

Chemistry 13

[0098]

[0099]

Chemistry 14

[0100]

[0101]

Chemistry 15

[0102]

[0103]

Chemistry 16

[0104]

[0105]

Chemistry 17

[0106]

[0107] [Chemistry 18]

[0108]

[0109]

Chemistry 19

[0110]

[0111]

Chemistry 20

[0112]

[0113]

Chemistry 21

[0114]

[0115]

Chemistry 22

[0116]

[0117]

Chemistry 23

[0118]

[0119]

Chemistry 24

[0120]

[0121]

Chemistry 25

[0122]

[0123]

Chemistry 26

[0124]

[0125]

Chemistry 27

[0126]

[0127]

Chemistry 28

[0128]

[0129]

Chemistry 29

[0130]

[0131]

Transformation 30

[0132]

[0133]

Chemistry 31

[0134]

[0135]

Chemistry 32

[0136]

[0137] The compounds of the present invention represented by the general formula (1) can be synthesized using known methods.

[0138] For example, the introduction of an acceptor into 4H-cyclopentano[2,1-b:3,4-b']dithiophene-4-one, as in compound (A-6) of the present invention, is carried out using the method of Non-Patent Literature 1, and the introduction of an alkyl group into 4H-cyclopentano[2,1-b:3,4-b']dithiophene, as in compound (A-35) of the present invention, is carried out using the method of Non-Patent Literature 2, yielding compounds represented by formulas (4) and (5) below. Subsequently, a bromination reaction is performed using a known method, followed by a Suzuki-Miyaura cross-coupling reaction between the obtained monobrominated product represented by formulas (6) and (7) and the borate ester compound represented by formula (8), and then another bromination reaction is performed. After dimerizing the obtained compound using a Stille coupling reaction, it is oxidized using an oxidizing agent, thereby synthesizing the compound of the present invention represented by general formula (1).

[0139]

Transformation 33

[0140]

[0141]

Transformation 34

[0142]

[0143]

Chemistry 35

[0144]

[0145] Purification methods for the compounds represented by the general formula (1) of the present invention can be performed by column chromatography-based purification, solvent-based recrystallization, reprecipitation, and washing. Furthermore, the identification of these compounds can be performed by nuclear magnetic resonance (NMR) analysis or mass spectrometry analysis.

[0146] The compounds of the present invention represented by the general formula (1) can be used as near-infrared absorbing pigments. In addition to the organic compounds of the present invention represented by the general formula (1), they can also be used in combination with known near-infrared absorbing substances. Furthermore, as near-infrared absorbing pigment compositions, they can be used in the form of containing solvents, additives, etc. Moreover, near-infrared absorbing pigments can also be used to prepare near-infrared absorbing inks by dissolving or dispersing them in a solvent.

[0147] The compounds of the present invention represented by the above general formula (1) can be used in near-infrared absorbing materials, organic electronic devices, etc. Alternatively, the compounds can be used in various applications as compositions dissolved or dispersed in various media (the media can be liquids such as organic solvents or solids such as polymer materials). Furthermore, the compounds or compositions can be used to form films, and these films can then be used for the aforementioned applications.

[0148] The compounds of the present invention represented by the general formula (1) have solubility suitable for solution processes. In particular, it is also contemplated to use the compounds of the present invention represented by the general formula (1) in the form of compositions in solution processes to manufacture organic electronic devices. As used in this specification, "solution process" refers to a process in which a composition in the form of a solution, dispersion, emulsion, etc., formed by dissolving a compound in an organic solvent is coated and components are easily manufactured.

[0149] Thin films can be made using near-infrared absorbing pigment compositions containing compounds of the present invention represented by the general formula (1).

[0150] In the case of solution coating, the near-infrared absorbing pigment composition may contain additives, binder polymers, etc. The coating solution may be prepared by simply dissolving or dispersing the compounds in a solvent, or by dissolving or dispersing these compounds and binder polymers in a solvent. Specifically, examples of binder polymers include: poly-N-vinylcarbazole, polyarylates, polystyrene, polyesters, polysiloxanes, polymethyl acrylate, polymethyl methacrylate, polyethers, polycarbonates, polyamides, polyimides, polyamide-imides, parylene, polyethylene, polyethylene ether, polypropylene ether, polyphenylene ether, polyethersulfone, polyaniline and its derivatives, polythiophene and its derivatives, polyphenylene ethylene and its derivatives, polyphenylene sulfide and its derivatives, polyfluorene and its derivatives, polythiophene ethylene and its derivatives, and other organic or inorganic polymers.

[0151] Methods for forming thin films typically include: vapor phase methods such as resistance heating evaporation, electron beam evaporation, sputtering, and molecular lamination, which are vacuum processes; solution methods such as spin coating, dropcasting, dip coating, and spraying; letterpress printing such as flexographic printing and resin letterpress printing; offset printing such as offset printing, dry offset printing, and pad printing; gravure printing such as gravure printing; screen printing such as silkscreen printing; carbon copy printing; stencil printing such as lithography; inkjet printing; and micro-contact printing; as well as methods that combine multiple of these methods.

[0152] Solvents used in film fabrication include: aromatic organic solvents such as benzene, toluene, xylene, mesitylene, tetrahydronaphthalene (1,2,3,4-tetrahydronaphthalene), monochlorobenzene, o-dichlorobenzene, m-dichlorobenzene, p-dichlorobenzene, and nitrobenzene; haloalkane organic solvents such as dichloromethane, chloroform, 1,2-dichloroethane, 1,1,2-trichloroethane, and dichloromethane; nitrile solvents such as benzonitrile and acetonitrile; and diethyl ether, tetrahydrofuran (hereinafter referred to as THF), dioxane, diisopropyl ether, cyclopentylmethyl ether, ethylene glycol dimethyl ether, and ethylene glycol dimethyl ether. Ether solvents such as ethyl ether and propylene glycol monomethyl ether (PGME); ester solvents such as ethyl acetate, n-butyl acetate, and propylene glycol monomethyl ether acetate (PGMEA); alcohol solvents such as methanol, isopropanol, n-butanol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, cyclohexanol, and 2-n-butoxyethanol; ketone solvents such as acetone and cyclohexanone; amide solvents such as N,N-dimethylformamide (DMF) and N-methylpyrrolidone (NMP); dimethyl sulfoxide (DMSO); chloroform (trichloromethane), etc. However, these solvents are not limited to these. Furthermore, one or more of the above solvents may be used, or the solvent may be selected based on the structure.

[0153] The thickness of the thin film varies depending on its application, but is generally preferred to be 1 nm to 10 μm, more preferably 5 nm to 3 μm, and even more preferably 10 nm to 1 μm.

[0154] [Evaluation of solubility]

[0155] Regarding the solubility of the compound of the present invention represented by the general formula (1), the solubility (or saturated solubility) is evaluated visually after adding the compound of the present invention to an organic solvent and stirring for about 1 or 2 minutes at room temperature (25±5°C) or placing it in an ultrasonic cleaner. Regarding solubility, it is necessary to have the solubility required in the manufacturing process of components, etc., based on solution processes; higher solubility is preferred.

[0156] [Lightfastness Evaluation]

[0157] Lightfastness testing can be performed by irradiating the sample with light for a certain period of time using a testing machine that simulates sunlight including ultraviolet light, and then measuring the changes in hue and absorbance before and after the test. In this invention, a xenon arc lamp weathering instrument was used for irradiation, and the change in absorbance at the wavelength of maximum absorption was measured using a UV-Vis spectrophotometer. When used industrially as a pigment, higher lightfastness is preferred.

[0158] [Organic electronic devices]

[0159] Organic electronic devices can be fabricated using the compounds of the present invention represented by general formula (1). Examples of organic electronic devices include, for instance, photoelectric conversion elements such as solar cells and light sensors, thin-film transistors, and organic EL elements.

[0160] As an embodiment of the present invention, with regard to organic photoelectric conversion elements particularly expected to be used in the near-infrared region, a photoelectric conversion element used as a near-infrared light absorbing material will be described.

[0161] Furthermore, although not detailed here, near-infrared light above 700nm has high transmittance to biological tissues. Therefore, it can also be used for the observation of tissues within living organisms, and can be applied in various forms in medical fields such as pathological analysis and diagnosis, depending on the purpose.

[0162] Photoelectric conversion element

[0163] A photoelectric conversion element is a device in which a photoelectric conversion section is disposed between a pair of opposing electrodes. The compound represented by general formula (1) of the present invention has near-infrared light absorption characteristics, and therefore is expected to be used as a photoelectric conversion element, and can be considered for use as a photoelectric conversion section of a photoelectric conversion element. The photoelectric conversion element can be used as an imaging element in solar cells, near-infrared light sensors, near-infrared light image sensors, etc.

[0164] The compound represented by the general formula (1) can be used as a constituent material of the photoelectric conversion section of a photoelectric conversion element. The photoelectric conversion section is mostly composed of a photoelectric conversion layer and one or more thin film layers other than the photoelectric conversion layer, selected from electron transport layers, hole transport layers, electron blocking layers, hole blocking layers, and interlayer contact improvement layers. The compound of the present invention is considered useful as a light-absorbing material, a photoelectric conversion material, a charge transport material, etc., and is preferably used as a thin film layer of the photoelectric conversion layer. Especially in the case of light-absorbing materials, photoelectric conversion materials, etc., used in organic thin-film solar cells, it is expected to efficiently capture solar energy for photoelectric conversion. The photoelectric conversion layer may be composed solely of the compound represented by the general formula (1), or it may contain known light-absorbing materials, other additives, etc., in addition to the compound represented by the general formula (1).

[0165] The materials used as electrodes for photoelectric conversion elements are not particularly limited as long as they have a certain degree of conductivity. Preferred selection is based on factors such as the closeness of contact with adjacent photoelectric conversion layers or other layers, electron affinity, ionization potential, and stability.

[0166] Specific examples of conductive materials used in electrodes include: conductive transparent oxide semiconductors such as tin-doped indium oxide (ITO), fluorine-doped tin oxide (FTO), and indium-tin composite oxides; metals such as gold, silver, platinum, chromium, aluminum, iron, cobalt, nickel, and tungsten; inorganic conductive materials such as copper iodide and copper sulfide; conductive polymers such as polythiophene, polypyrrole, and polyaniline; and carbon. These materials can also be mixed in multiples as needed.

[0167] In the electrodes, the transparent electrode film, i.e., the conductive support, used in at least one of the light-incident sides needs to have light transmittance capable of transmitting light participating in photoelectric conversion. Furthermore, the conductive support is a component that functions to extract current from the photoelectric conversion layer, and therefore a conductive substrate is preferred. Examples of suitable materials include ITO and FTO (fluorine-doped tin oxide).

[0168] The photoelectric conversion section sometimes includes a photoelectric conversion layer and a thin film other than the photoelectric conversion layer. The photoelectric conversion layer typically uses an organic semiconductor film, but this organic semiconductor film can be a single layer or multiple layers. In the case of a single layer, a p-type organic semiconductor layer, an n-type organic semiconductor layer, or a mixture thereof can be used. On the other hand, in the case of multiple layers, there are approximately 2 to 10 layers, which is a structure consisting of stacked p-type organic semiconductor layers, n-type organic semiconductor layers, or a mixture thereof, and buffer layers can also be inserted between the layers. The compounds of the present invention can be considered for use as either p-type or n-type semiconductor materials.

[0169] Examples of thin film layers other than the photoelectric conversion layer constituting the photoelectric conversion unit include, for example, electron transport layers, hole transport layers, electron blocking layers, hole blocking layers, or interlayer contact improvement layers. The compounds of the present invention may also be considered for use in each layer.

[0170] <Applications of Near-Infrared Cut-Off Filters>

[0171] Near-infrared absorbing materials can also be used in near-infrared cut-off filters that selectively absorb light in specific wavelength regions, and in plant growth regulating films, etc. The compounds of the present invention and compositions containing these compounds have high near-infrared absorption capacity and excellent light resistance, and therefore can be considered as materials for constructing near-infrared cut-off filters, etc. Specific applications of near-infrared cut-off filters include color filters used in semiconductor applications, electronic devices, various sensors, liquid crystal display devices, and imaging elements.

[0172] [Color Filter]

[0173] When the compound of the present invention represented by general formula (1) is used as a near-infrared absorbing pigment in a color filter, it can be configured by a two-layer method in which a color filter layer and a near-infrared cut-off filter layer are formed on a substrate, or by a one-layer method in which both the functions of a color filter and a near-infrared cut-off filter are performed. In the case of a one-layer configuration, a thin-film filter can be fabricated by forming an optical filter layer.

[0174] In the case of a single-layer optical filter layer, the colorant for the filter comprises: a composition containing at least one near-infrared absorbing pigment represented by general formula (1) and components commonly used in the manufacture of color filters. It may contain other pigments such as dyes or pigments, resin components, organic solvents, and other additives such as photopolymerization initiators. Furthermore, these components can be selected from the list, and other components may be added as needed.

[0175] Regarding conventional color filters, for example, in the case of using a photolithography process, they can be obtained by mixing pigments such as dyes and pigments with resin components and solvents, then coating the prepared liquid onto a substrate such as glass or resin, and using a photomask to perform photopolymerization to create a colored pattern of a pigment-resin composite film that is soluble / insoluble in the solvent. After cleaning, the film is heated. Alternatively, in electrodeposition and printing methods, a mixture of pigments, resins, and other components is used to create colored patterns.

[0176] Dyes or pigments used as colorants for color filters include: red pigments such as CI Pigment Red 177, 209, 242, 254, 255, 264, 269, and CI Pigment Orange 38, 43, 71; other red lake pigments; yellow pigments such as CI Pigment Yellow 138, 139, 150; red dyes such as CI Acid Red 88 and CI Basic Violet 10; basic dyes such as CI Basic Blue 3, 7, 9, 54, 65, 75, 77, 99, 129; acid dyes such as CI Acid Blue 9 and 74; disperse dyes such as Disperse Blue 3, 7, 377; spirocyclic dyes; cyanine, indigo, phthalocyanine, anthraquinone, methine, triarylmethane, indanthrene, oxazine, dioxazine, azo, and xanthine; and other blue lake pigments, without particular limitation.

[0177] In the manufacturing process of colorants and filters, it is necessary to ensure good dissolution or dispersion in organic solvents containing resins, etc., and higher solubility or dispersibility in organic solvents is preferred. There are no particular limitations on the organic solvent; specifically, the same organic solvent used in the above-mentioned film formation process can be used.

[0178] As the resin component in a colorant for a color filter, any known resin can be used, provided it possesses the properties required for manufacturing the color filter resin film formed using it and for its application. Examples include, for instance, acrylic resins, polyolefin resins, styrene resins, polyimide resins, polyurethane resins, polyester resins, epoxy resins, vinyl ether resins, phenolic (phenolic varnish) resins, other transparent resins, photocurable resins, or thermocurable resins; their monomer or oligomer components can be appropriately combined. Alternatively, copolymers of these resins can also be used. In the case of liquid colorants, the resin content in these colorant colorants for color filters is preferably 5% to 95% by weight, more preferably 10% to 50% by weight.

[0179] In addition, surfactants, dispersants, defoamers, leveling agents, and other additives can be added depending on the intended use. Preferably, the additive content is appropriate, preferably within a range that reduces or increases solubility to the desired level without affecting the effectiveness of other similar additives used in the manufacture of products such as color filters. This content can be added at any time during the preparation of the colorant.

[0180] Other additives in the colorant for color filters of the present invention include photopolymerization initiators, crosslinking agents, and other components required for the polymerization and curing of resins. Additionally, surfactants, dispersants, and other components required for stabilizing the properties of the components in the liquid colorant for color filters can be included. These can all be known substances used in color filter manufacturing and are not particularly limited. The mixing ratio of the total amount of these additives in the solid components of the colorant for color filters is preferably 5% to 60% by mass, more preferably 10% to 40% by mass.

[0181]

Example

[0182] The present invention will be described in more detail below using examples, but the present invention is not limited to the following examples. Furthermore, the compounds obtained in the synthetic examples were identified through… 1 The analysis was performed using H-NMR (JNM-ECZ400S / L1 type nuclear magnetic resonance device manufactured by NEC Corporation), mass spectrometry (JMS-T100LP manufactured by NEC Corporation), and elemental analysis (JM10 manufactured by J-SCIENCE-LABO Corporation).

[0183] [Example 1]

[0184] <Synthesis of Compound (A-1)>

[0185] Under an argon gas flow, 2.07 g (0.0108 mol, manufactured by BLD Pharmach Ltd.) and 50 mL of dehydrated tetrahydrofuran were added to a reaction vessel, and the mixture was stirred at -2 °C in a salt ice bath. A solution of 50 mL of dehydrated tetrahydrofuran containing N-bromosuccinimide (1.86 g, 0.0105 mol, manufactured by Tokyo Chemical Industry Co., Ltd.) was added dropwise over 40 minutes. After stirring at 0 °C for 5 hours, the mixture was allowed to rise naturally and stand overnight. The solvent was removed by distillation, and the crude product was purified by silica gel column chromatography (SiO2 / hexane:hexane:chloroform = (1:2)). The fraction containing the target compound was concentrated to obtain a reddish-brown solid (2.55 g). The solid was further purified by silica gel column chromatography (SiO2 / hexane ~ hexane: chloroform = (1:1) (volume ratio)) to obtain a compound represented by the following formula (9) as a reddish-brown solid (yield: 1.19 g, yield: 41%).

[0186]

Transformation 36

[0187]

[0188] Under an argon gas flow, 2,6-di-tert-butyl-4-bromophenol (2.01 g, 0.00705 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), pinacol diborate (2.44 g, 0.00961 mol, manufactured by Kishida Chemical Co., Ltd.), potassium acetate (1.89 g, 0.0193 mol, manufactured by Fujifilm and Kazumitsu Chemical Co., Ltd.), and 85 mL of dehydrated 1,4-dioxane were added to the reaction vessel, and degassed in an ultrasonic cleaner (hereinafter referred to as ultrasonic) for 20 minutes. [1,1'-bis(diphenylphosphine)ferrocene]palladium(II) dichloromethane adduct (260 mg, 0.318 mmol, manufactured by Sigma-Aldrich) was added, and the mixture was heated and stirred at 84 °C for 22 hours. After the reaction was complete, the reaction solution was cooled to room temperature and then filtered through diatomaceous earth (Celite). The filtrate was washed with chloroform, and the solvent was removed by distillation of the filtrate to obtain the crude product. The crude product was purified by silica gel column chromatography (SiO2 / hexane ~ hexane:chloroform = (1:1.5) (volume ratio)) to obtain a compound represented by the following formula (10) as a white solid (yield: 1.44 g, yield: 62%).

[0189]

Chemistry 37

[0190]

[0191] Under an argon gas flow, the compound of formula (9) (1.21 g, 0.00446 mol), the compound of formula (10) (1.48 g, 0.00445 mol), 60 mL of tetrahydrofuran, and 30 mL of purified water were added to the reaction vessel, and the mixture was degassed by ultrasonication for 20 minutes. Sodium carbonate (950 mg, 0.00896 mol, manufactured by Kishida Chemical Co., Ltd.), tetra(triphenylphosphine)palladium (0) (267 mg, 0.231 mmol, manufactured by Kanto Chemical Co., Ltd.) were added, and the mixture was heated at 64 °C for 6.5 hours. After the reaction was completed, the reaction solution was cooled to room temperature, and 100 mL of ethyl acetate and 100 mL of local water were added. The mixture was separated, and the organic layer was washed twice with 100 mL of water, washed with saturated saline solution, dried with anhydrous magnesium sulfate, and the solvent was removed by distillation to obtain the crude product. The crude product was purified by silica gel column chromatography (SiO2 / hexane ~ hexane: ethyl acetate = 5:1 (volume ratio)) to obtain the following compound of formula (11) as a blackish-purple solid (yield: 1.64 g, yield: 93%).

[0192] The following compound (832 mg, 0.00210 mol), N-bromosuccinimide (411 mg, 0.00231 mmol, manufactured by Tokyo Chemical Industry Co., Ltd.), and 30 mL of dehydrated tetrahydrofuran were added to the reaction vessel and stirred at room temperature for 2.5 hours under an argon flow. After the reaction was completed, the solvent was removed by distillation to obtain a crude product as a blackish-purple solid. The crude product was purified by silica gel column chromatography (SiO2 / hexane ~ hexane: chloroform = 1:1.5 (volume ratio)), and the fraction containing the target compound was concentrated and filtered during crystallization to obtain the following compound (12) as a blackish-purple solid (yield: 604 mg, yield: 61%).

[0193] <NMR Analysis Results>

[0194] 1 H-NMR (400MHz, CDCL3): δ (ppm) = 1.47 (s, 18H), 5.37 (s, 1H), 6.99 (s, 1H), 7.08 (s, 1H), 7.33 (s, 2H)

[0195]

Transformation 38

[0196]

[0197] The compound of formula (12) (384 mg, 0.808 mmol), bis(tributyltin) (215 μL, 0.426 mmol, manufactured by Sigma-Aldrich), and 5 mL of dehydrated tetrahydrofuran were added to the reaction vessel under an argon gas flow, and degassed by sonication for 20 minutes. A 33 wt% xylene solution (117 mg, 0.578 mmol) of tris(dibenzylacetone)palladium(0) (38.8 mg, 0.0424 mmol, manufactured by Sigma-Aldrich) and tri-tert-butylphosphine (manufactured by Fujifilm and Koko Pure Chemicals Co., Ltd.) was added, and the mixture was heated under reflux at 63 °C for 9 hours. After the reaction was completed, the reaction solution was cooled to room temperature, and the solvent was removed by distillation to obtain a crude product. 20 mL of acetone was added to the crude product, and the mixture was sonicated. After filtration, the filtrate was washed with acetone to obtain a black solid. 500 mL of chloroform was added to the black solid, and the mixture was sonicated at 50 °C for 30 minutes. The mixture was then filtered through silica gel, and the filtrate was concentrated to obtain a blackish-green solid. Acetone was added to the solid, and the mixture was sonicated and filtered to obtain the compound of the following formula (13) as a blackish-green solid (yield: 99.4 mg, yield: 31%).

[0198] <NMR Analysis Results>

[0199] 1 H-NMR (400MHz, CDCL3): δ (ppm) = 1.48 (s, 36H), 5.38 (s, 2H), 7.03 (s, 2H), 7.10 (s, 2H), 7.35 (s, 4H)

[0200] <Mass Spectrometry Analysis Results>

[0201] TOF-MS(ESI) m / z calc.for C 46 H 46 O4S4(M + ):790.23,found:790.25

[0202]

Chemistry 39

[0203]

[0204] The compound of formula (13) above (21.0 mg, 0.0265 mmol) and 80 mL of 1,2-dichlorobenzene were added to the reaction vessel. Ultrasonic treatment was applied, and the mixture was heated with a hot air gun to dissolve the raw materials. The insoluble components were filtered, and 7.5 g of 10% potassium hydroxide aqueous solution and potassium ferricyanide (85 mg, 0.258 mmol, manufactured by Fujifilm and Kohden Chemical Co., Ltd.) were added to the filtrate under an argon gas flow. The mixture was stirred at room temperature for 5 hours. After the reaction was complete, the reaction solution was filtered, and the filtrate was washed with water and acetone to obtain the compound of formula (A-1) below as a brown solid.

[0205] <Mass Spectrometry Analysis Results>

[0206] TOF-MS(ESI) m / z calc.for C 46 H 44 O4S4([M+H) + ):789.22,found:789.21

[0207]

Chemistry 40

[0208]

[0209] <Absorption Spectroscopy Measurement>

[0210] A 1,2-dichlorobenzene solution of the prepared compound (A-1) (concentration 1.0 × 10⁻⁶) -5 The concentration of mol / L was measured using a UV-Vis spectrophotometer (Hitachi, U-3000). The absorption maximum wavelength (nm) and molar absorptivity (Mb / L) were determined based on the UV-Vis absorption spectroscopy results. -1 cm -1 The values ​​of ) are shown in Table 2.

[0211] [Example 2]

[0212] <Synthesis of Compound (A-6)>

[0213] 30 mL of dehydrated tetrahydrofuran was added to the reaction vessel under an argon gas flow, and the vessel was cooled at -2 °C in a salt-ice bath. Titanium tetrachloride (2.89 mL, 0.00265 mol, manufactured by Fujifilm and Koichi Chemical Co., Ltd.) was added to the reaction vessel while stirring. Then, 30 mL of a solution of dehydrated tetrahydrofuran containing 4H-cyclopenta[1,2-b:5,4-b']dithiophene-4-one (598 mg, 0.00311 mol, manufactured by BLDpharmatech Ltd.) and dihexyl malonate (4.40 mL, 0.0153 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), and pyridine (3.86 mL, 0.0478 mol, manufactured by Nakalai Tesque Co., Ltd.) were added. The salt-ice bath was removed, and the vessel was allowed to heat naturally and stirred at room temperature for 5 hours. After the reaction was complete, 100 mL of water and 200 mL of chloroform were added to the reaction solution, and the mixture was separated. The organic layer was dried with anhydrous magnesium sulfate, and the solvent was removed by distillation to obtain a crude product (red oily substance). The crude product was purified by silica gel column chromatography (SiO2 / hexane:chloroform = 50:1 to 1:1 (volume ratio)). The fraction containing the target compound was concentrated, 100 mL of local water was added, and the mixture was cooled in an ice bath. The solid was filtered when it precipitated, and the filtrate was washed with local water to obtain a reddish-black solid. The solid was dissolved in 150 mL of acetone, dried with anhydrous magnesium sulfate, and the solvent was removed by distillation to obtain the compound of formula (14) as a reddish-black solid (yield: 1.54 g).

[0214] Under an argon gas flow, 1.42 g (0.00302 mol) of the compound of formula (14) and 44 mL of dehydrated tetrahydrofuran were added to the reaction vessel. At room temperature, while stirring, 30 mL of a solution of N-bromosuccinimide (536 mg, 0.00301 mol, manufactured by Tokyo Chemical Industry Co., Ltd.) in dehydrated tetrahydrofuran was added dropwise over 4 hours, followed by stirring for 30 minutes. After the reaction was completed, the solvent was removed by distillation of the reaction solution to obtain the crude product. The crude product was purified by silica gel column chromatography (SiO2 / hexane:chloroform = 50:1 to 1:1.5 (volume ratio)) to obtain the compound of formula (15) as a blackish-purple solid (yield: 966 mg, yield: 57%).

[0215] <NMR Analysis Results>

[0216] 1 H-NMR (400MHz, CDCL3): δ (ppm) = 0.87 (m, 6H), 1.27-1.45 (m, 12H), 1.72 (m, 4H), 4.31 (m, 4H), 7.02 (d, 1H), 7.20 (d, 1H), 7.38 (s, 1H)

[0217]

Chemistry 41

[0218]

[0219] The compound of formula (15) (903 mg, 1.72 mmol), the borate ester of formula (10) (572 mg, 1.72 mmol), 43 mL of tetrahydrofuran, and 21 mL of purified water were added to the reaction vessel under an argon gas flow. The mixture was then degassed by sonication for 20 minutes. Sodium carbonate (366 mg, 3.45 mmol, manufactured by Kishida Chemical Co., Ltd.) and tetra(triphenylphosphine)palladium(0) (101 mg, 0.087 mmol, manufactured by Kanto Chemical Co., Ltd.) were added, and the mixture was heated and stirred at 62 °C for 3.5 hours. After the reaction was complete, the reaction solution was cooled to room temperature, and 200 mL of ethyl acetate and 150 mL of local water were added. The mixture was separated. The aqueous layer was extracted twice with 100 mL of ethyl acetate. The resulting organic layer was dried over anhydrous magnesium sulfate, and the solvent was removed by distillation to obtain the crude product. The crude product was purified by silica gel column chromatography (SiO2 / hexane-hexane:ethyl acetate = 20:1 (volume ratio)) and then purified again by silica gel column chromatography (NH-SiO2 / hexane-hexane:ethyl acetate = 2:1 (volume ratio)) to obtain the following compound (16) as a purple oily substance (yield: 803 mg, yield: 72%).

[0220] The following compound (684 mg, 1.05 mmol), 50 mL of dehydrated tetrahydrofuran, and N-bromosuccinimide (189 mg, 1.06 mmol, manufactured by Tokyo Chemical Industry Co., Ltd.) were added to a reaction vessel and stirred at room temperature for 2.5 hours under an argon atmosphere. After the reaction was completed, the solvent was removed by distillation of the reaction solution to obtain a crude product. The crude product was purified by silica gel column chromatography (SiO2 / hexane ~ hexane: chloroform = 1:2 (volume ratio)) to obtain the following compound (17) as a purple oil (yield: 679 mg, 89%).

[0221] <NMR Analysis Results>

[0222] 1 H-NMR (400MHz, CDCL3): δ (ppm) = 0.85-0.92 (m, 6H), 1.28-1.41 (m, 12H), 1.47 (s, 1 8H), 1.73(m, 4H), 4.32(m, 4H), 5.32(s, 1H), 7.21(s, 1H), 7.32(s, 2H), 7.43(s, 1H)

[0223]

Chemistry 42

[0224]

[0225] The compound of formula (17) above (499 mg, 0.684 mmol), 20 mL of dehydrated tetrahydrofuran, and bis(tributyltin) (172 μL, 0.340 mmol, manufactured by Sigma-Aldrich) were added to the reaction vessel under an argon gas flow. The mixture was ultrasonically degassed for 15 minutes. Then, a 33 wt% xylene solution of tri-tert-butylphosphine (manufactured by Fujifilm and Koko Pure Chemicals Co., Ltd.) (98.0 mg, 0.160 mmol) and tris(dibenzylacetone)dipalladium(0) (33.6 mg, 0.0367 mmol, manufactured by Sigma-Aldrich) were added. The mixture was heated and stirred at 62 °C for 2 hours. Then, a 33 wt% xylene solution of tri-tert-butylphosphine (116 mg, 0.189 mmol) and tris(dibenzylacetone)dipalladium(0) (31.6 mg, 0.156 mmol) were added, and the mixture was heated and stirred at 62 °C for 13.5 hours. After the reaction was completed, the reaction solution was cooled to room temperature and the solvent was removed by distillation to obtain the crude product. The crude product was purified by silica gel column chromatography (SiO2 / hexane ~ hexane:chloroform = 1:2 (volume ratio)). The fraction containing the target compound was concentrated to obtain a black-green solid (760 mg). 10 mL of methanol was added to the solid, and after sonication, the mixture was filtered to obtain the compound of the following formula (18) as a black-green solid (yield: 301 mg, yield: 68%).

[0226] <NMR Analysis Results>

[0227] 1 H-NMR (400MHz, CDCL3): δ (ppm) = 0.86-0.92 (m, 12H), 1.28-1.45 (m, 24H), 1.48 (s, 3 6H), 1.75(m, 8H), 4.35(m, 8H), 5.32(s, 2H), 7.28(s, 2H), 7.34(s, 4H), 7.41(s, 2H)

[0228] <Mass Spectrometry Analysis Results>

[0229] TOF-MS(ESI) m / z calc.for C 76 H 98 O 10 S4([M)) + ): 1298.60, found: 1298.59

[0230] <Elemental Analysis Results>

[0231] Anal.Calcd.For C 76 H 98 O 10S4: C, 70.23; H, 7.60; N, 0. Found: C, 70.58; H, 7.58; N, 0.18.

[0232]

Chemistry 43

[0233]

[0234] The compound of formula (18) above (226 mg, 0.174 mmol) was added to the reaction vessel, followed by 10 mL of dehydrated 1,2-dichlorobenzene and lead oxide (IV) (419 mg, 1.75 mmol, manufactured by Kanto Chemical Co., Ltd.), and ultrasonication was applied for 30 minutes. Lead oxide (IV) was added again in the same manner, and ultrasonication was applied for 60 minutes. This operation was repeated twice (858 mg, 3.58 mmol of lead oxide (IV) was added), and ultrasonication was applied for 4 hours to terminate the reaction. The reaction solution was filtered with diatomaceous earth, and the solvent was removed by distillation of the filtrate, thereby obtaining a crude product as a dark brown solid. 60 mL of chloroform was added to the solid, and the insoluble components were filtered with diatomaceous earth, followed by filtration of the filtrate using a syringe filter. The solvent was removed by distillation of the filtrate, and 5 mL of acetone was added. The mixture was ultrasonicated and filtered, and washed with acetone to obtain the compound of formula (A-6) below as a black solid (yield: 187 mg, 83%).

[0235] <Mass Spectrometry Analysis Results>

[0236] TOF-MS(ESI) m / z calc.for C 76 H 96 O 10 S4([M+H)) + ): 1297.59, found: 1297.57

[0237] <Elemental Analysis Results>

[0238] Anal.Calcd.For C 76 H 96 O 10 S4: C, 70.34; H, 7.46; N, 0. Found: C, 70.05; H, 7.41; N, 0.12.

[0239]

Chemistry 44

[0240]

[0241] <Solubility Evaluation>

[0242] The obtained compound (A-6) was weighed in a transparent sample tube and prepared into a 5 wt% solution using tetrahydrofuran. After being placed in an ultrasonic cleaner at room temperature (25±2℃) for 1 minute, the solubility was evaluated by visually confirming the presence or absence of dissolved residue. The results are shown in Table 1. For the judgment criteria, complete dissolution (25±2℃) was marked as ○, residual suspension (25±2℃) as △, and insolubility (25±2℃) as ×.

[0243] <Absorption Spectroscopy Measurement>

[0244] A 1,2-dichlorobenzene solution (concentration 5.0 × 10⁻⁶) of compound (A-6) was prepared by replacing compound (A-1). -6 The concentration (mol / L) was measured using a UV-Vis spectrophotometer (Shimadzu Corporation, UV-3600). Otherwise, UV-Vis absorption spectroscopy was performed in the same manner as in Example 1, and the results are shown in Table 2. Additionally, the absorption spectrum of compound (A-6) is shown in Table 2. Figure 1 middle.

[0245] [Example 3]

[0246] <Synthesis of Compound (A-35)>

[0247] Under an argon atmosphere, 4H-cyclopentano[2,1-b:3,4-b']dithiophene (1.08 g, 6.06 mmol, manufactured by Tokyo Chemical Industry Co., Ltd.), 125 mL of dimethyl sulfoxide dehydrated with molecular sieves, 1-bromohexane (2.12 mL, 15.2 mmol, manufactured by Tokyo Chemical Industry Co., Ltd.), and potassium iodide (28.0 mg, 0.169 mmol, manufactured by Pure Chemical Industries Co., Ltd.) were added to the reaction vessel, and the mixture was cooled to 2°C in an ice bath. Potassium hydroxide (905 mg, 16.1 mmol, manufactured by Fujifilm and Wakamitsu Chemical Co., Ltd.), which had been pre-crushed in a mortar, was added to the reaction solution. The ice bath was removed, and the mixture was stirred for 5 hours while being heated to room temperature. Then, potassium hydroxide (71.0 mg, 1.27 mmol) was added, and the mixture was stirred further at room temperature for 15 minutes. The mixture was allowed to stand overnight, and then potassium hydroxide (112 mg, 2.00 mmol) was added, and the mixture was stirred for 7 hours at room temperature. After the reaction was completed, 250 mL of local water and 200 mL of ethyl acetate were added, and the mixture was separated. The organic layer was washed with 200 mL of local water, saturated saline solution, and saturated ammonium chloride aqueous solution. The separated organic layer was dried with anhydrous magnesium sulfate and the solvent was removed by distillation to obtain a crude product as a brown oily substance. The crude product was purified by silica gel column chromatography (SiO2 / hexane) to obtain a compound of the following formula (19) as a yellow oily substance (yield: 1.59 g, yield: 76%).

[0248] The compound represented by formula (19) (295 mg, 0.851 mmol), 5 mL of tetrahydrofuran, and N-bromosuccinimide (151 mg, 0.849 mmol, manufactured by Tokyo Chemical Industry Co., Ltd.) were added to the reaction vessel and stirred at 0°C for 4 hours in an ice bath. After the reaction was completed, the solvent was removed by distillation of the reaction solution to obtain a crude product. The crude product was purified by silica gel column chromatography (SiO2 / hexane) to obtain a mixture of monobrominated, dibrominated, and compound represented by formula (19) containing the target compound of formula (20) as a yellow oily substance (yield: 343 mg (monobrominated: 60 wt%)).

[0249]

Chemistry 45

[0250]

[0251] The compound represented by formula (20) above (161 mg, 0.234 mmol), 5 mL of tetrahydrofuran, and 2.5 mL of purified water were added to the reaction vessel, and the mixture was degassed by ultrasound for 15 minutes. Sodium carbonate (67.8 mg, 0.640 mmol, manufactured by Kishida Chemical Co., Ltd.) and tetra(triphenylphosphine)palladium(0) (19.0 mg, 0.0164 mmol, manufactured by Kanto Chemical Co., Ltd.) were added, and the mixture was heated and stirred at 60°C for 1.5 hours. The compound represented by formula (10) above (28.1 mg, 0.0845 mmol) was added, and the mixture was heated and stirred at 60°C for 50 minutes. After the reaction was completed, the reaction solution was cooled to room temperature, and 50 mL of local water and 50 mL of ethyl acetate were added. The mixture was separated, and the organic layer was dried with anhydrous magnesium sulfate and the solvent was removed by distillation to obtain the crude product. The crude product was purified by silica gel column chromatography (SiO2 / hexane ~ hexane: ethyl acetate = 20:1 (volume ratio)) to obtain the compound of the following formula (21) (yield: 112 mg, yield: 87%).

[0252] The compound of formula (21) (99.8 mg, 0.181 mol), 2 mL of tetrahydrofuran, and N-bromosuccinimide (32.9 mg, 0.185 mmol, manufactured by Tokyo Chemical Industry Co., Ltd.) were added to the reaction vessel and stirred at room temperature for 25 minutes. After the reaction was completed, the solvent was removed by distillation to obtain the crude product. The crude product was purified by silica gel column chromatography (SiO2 / hexane) to obtain the compound of formula (22) (yield: 89.4 mg, yield: 78%).

[0253] <NMR Analysis Results>

[0254] 1H-NMR (400MHz, CDCL3): δ (ppm) = 0.82 (t, 6H), 0.92-0.98 (m, 4H), 1.12-1.22 (m, 12H), 1.49(s, 18H), 1.79-1.83(m, 4H), 5.27(s, 1H), 6.93(s, 1H), 6.99(s, 1H), 7.40(s, 2H)

[0255]

Chemistry 46

[0256]

[0257] The compound of formula (22) above (90.9 mg, 0.137 mmol), bis(tributyl)tin (35 μL, 0.0693 mmol, manufactured by Sigma-Aldrich), and 5 mL of dehydrated tetrahydrofuran were added to the reaction vessel, and degassed by sonication for 15 minutes under an argon flow. A 33 wt% xylene solution of tri-tert-butylphosphine (manufactured by Fujifilm and Koimitsu Chemical Co., Ltd.) (18.5 mg, 0.0302 mmol) and tris(dibenzylacetone)dipalladium(O) (6.4 mg, 0.00699 mmol, manufactured by Sigma-Aldrich) were added, and the mixture was heated to reflux at 61 °C for 2 hours. After the reaction was completed, the reaction solution was cooled to room temperature, and the solvent was removed by distillation to obtain the crude product. The crude product was purified twice by silica gel column chromatography (SiO2 / hexane-hexane: ethyl acetate (or chloroform) = 10:1 (volume ratio)) to obtain an orange-brown solid. The solid was dissolved in 1 mL of chloroform, 1 mL of methanol was added, and the solid was precipitated. The solid was then filtered off to obtain the following compound (23) as a yellow tea-colored solid (yield: 33.6 mg, yield: 45%).

[0258] <NMR Analysis Results>

[0259] 1 H-NMR (400MHz, THF-d8): δ (ppm) = 0.81 (m, 12H), 0.98-1.04 (m, 8H), 1.14-1.22 (m, 24H) ,1.47(s,36H),1.92-1.94(m,8H),6.35(s,2H),7.15(s,2H),7.16(s,2H),7.42(s,4H)

[0260] <Mass Spectrometry Analysis Results>

[0261] TOF-MS(ESI) m / z calc.for C 70 H 98 O2S4([M] + ): 1098.65, found: 1098.66

[0262] <Elemental Analysis Results>

[0263] Anal.Calcd.For C 70 H 98 O2S4: C, 76.45; H, 8.98; N, 0. Found: C, 76.51; H, 8.87; N, 0.23.

[0264]

Chemistry 47

[0265]

[0266] The compound represented by formula (23) above (10.5 mg, 0.00955 mmol), 5 mL of 1,2-dichlorobenzene, potassium ferricyanide (21.8 mg, 0.0662 mmol, manufactured by Fujifilm and Koufuku Kogyo Co., Ltd.), and 1.3 mL (0.145 mmol) of potassium hydroxide aqueous solution (308 mg potassium hydroxide / 50 mL purified water) were added to the reaction vessel and stirred at room temperature for 5 hours. After the reaction was completed, 20 mL of local water and 30 mL of 1,2-dichlorobenzene were added to the reaction solution, and the mixture was separated. The solvent was removed by distillation of the organic layer to obtain a crude product. 5 mL of acetone was added to the crude product, and the mixture was ultrasonically cleaned to obtain the compound of formula (A-35) as a reddish-brown solid (yield: 7.8 mg, 74%).

[0267] <Mass Spectrometry Analysis Results>

[0268] TOF-MS(ESI) m / z calc.for C 70 H 96 O2S4([M+H)) + ):1097.64,found:1097.67

[0269] <Elemental Analysis Results>

[0270] Anal.Calcd.For C 70 H 96 O2S4: C, 76.59; H, 8.81; N, 0. Found: C, 76.74; H, 8.84; N, 0.26.

[0271]

Chemistry 48

[0272]

[0273] <Solubility Evaluation>

[0274] Solubility was evaluated in the same manner as in Example 2, except that (A-35) was used instead of compound (A-6). The results are shown in Table 1.

[0275] <Absorption Spectroscopy Measurement>

[0276] A dichloromethane solution (concentration 1.0 × 10⁻⁶) was prepared to replace compound (A-1) to prepare compound (A-35). -6 The concentration (mol / L) was measured using a UV-Vis spectrophotometer (Shimadzu Corporation, UV-3600). Otherwise, UV-Vis absorption spectroscopy measurements were performed in the same manner as in Example 1. The results are shown in Table 2.

[0277] [Example 4]

[0278] <Synthesis of Compound (A-27)>

[0279] 3,3'-dibromo-5,5'-bis(trimethylsilyl)-2,2'-bithiophene (5.05 g, 0.0108 mol, manufactured by Tokyo Chemical Industry Co., Ltd.) was added to the reaction vessel for argon purging. Dehydrated tetrahydrofuran (100 mL) was added, and the mixture was cooled to below -70°C using a dry ice-acetone bath. A hexane solution of n-butyllithium (1.55 M) (15 mL, 0.0232 mol, manufactured by Kanto Chemical Co., Ltd.) was added dropwise over 22 minutes, and the mixture was stirred at below -70°C for 2 hours. Dichlorodibutylsilane (3.8 mL, 0.0137 mol) was added dropwise to the reaction solution over 4 minutes, and the mixture was heated to room temperature over 2 hours and 25 minutes to terminate the reaction. Local water and ethyl acetate were added to the reaction solution, and the mixture was separated. The organic layer was washed twice with local water. The separated organic layer was dried over anhydrous magnesium sulfate, and the solvent was removed by distillation to obtain the crude product. The crude product was purified by silica gel column chromatography (SiO2 / hexane) twice to obtain a compound of the following formula (24) as a pale yellow oily substance (yield: 4.44 g, yield: 81.0%).

[0280] The compound of formula (24) (3.31 g, 6.53 mmol), 186 mL of chloroform, and 1.26 mL of trifluoroacetic acid (13.1 mmol) were added to the reaction vessel and stirred at room temperature for 25 minutes. After the reaction was completed, local water was added to the reaction solution, and the mixture was separated. The organic layer was washed with saturated brine, dried with anhydrous magnesium sulfate, and the solvent was removed by distillation to obtain the crude product. The crude product was purified by silica gel column chromatography (SiO2 / hexane) to obtain the compound of formula (25) as a yellow oily substance (yield: 2.15 g, yield: 108%).

[0281]

Chemistry 49

[0282]

[0283] The reaction vessel was purged with argon, and a 12 mL solution of dehydrated tetrahydrofuran (1.62 g, 0.00528 mol) of the compound of formula (25) was added. The mixture was cooled to below -70°C in a dry ice-acetone bath. A hexane solution of n-butyllithium (1.58 M) (3.1 mL, 0.00490 mol, manufactured by Kanto Chemical Co., Ltd.) was added dropwise over 5 minutes, and the mixture was stirred at below -70°C for 3 hours and 20 minutes. A 2.5 mL solution of dehydrated tetrahydrofuran (1.08 g, 0.00542 mol, manufactured by Tokyo Chemical Industry Co., Ltd.) was added dropwise over 10 minutes, and the mixture was stirred at below -70°C for 2 hours. The reaction vessel was then removed from the dry ice-acetone bath, allowed to warm naturally, and allowed to stand overnight. After stirring at room temperature for 4 hours, the solvent was removed by distillation to obtain the crude product. 100 mL of hexane was added to the crude product, the precipitate was filtered, and the solvent was removed by distillation of the filtrate, thereby obtaining a blackish-green oily substance containing the compound of the following formula (26) (yield: 2.11 g, HPLC purity 79%).

[0284] Compound of formula (26) (2.11 g, HPLC purity 79%, 0.00355 mol), 2,6-di-tert-butyl-4-bromophenol (1.11 g, 0.00389 mol, manufactured by Tokyo Chemical Industry Co., Ltd.), and 30 mL of dehydrated tetrahydrofuran were added to a reaction vessel under an argon gas flow. The mixture was then degassed by sonication for 15 minutes. Tetra(triphenyl)phosphine palladium (0) (0.209 g, 0.000181 mol, manufactured by Tokyo Chemical Industry Co., Ltd.) was added, and the mixture was heated under reflux at 63°C for 2 hours and 40 minutes. After cooling the reaction solution to room temperature, it was allowed to stand overnight. The mixture was then heated under reflux at 63°C for 50 minutes again, and tetra(triphenyl)phosphine palladium (0) was added again, followed by heating under reflux at 63°C for 8 hours and 25 minutes. After the reaction was complete, the reaction solution was cooled to room temperature, and the solvent was removed by distillation to obtain the crude product. The crude product was purified twice by silica gel column chromatography (SiO2 / hexane ~ hexane: chloroform = 5:1) to obtain the following compound (27) as an orange-yellow solid (yield: 1.11 g, yield: 61%).

[0285] <NMR Analysis Results>

[0286] 1 H-NMR (400MHz, CDCL3): δ (ppm) = 0.85 (t, 6H), 0.91-0.94 (m, 4H), 1.30-1.40 (m, 8H) ), 1.49(s, 18H), 5.26(s, 1H), 7.06(d, 1H), 7.11(s, 1H), 7.19(d, 1H), 7.41(s, 2H)

[0287] [Transformation 50]

[0288]

[0289] The compound of formula (27) above (1.11 g, 0.00217 mol) and 80 mL of dehydrated tetrahydrofuran were added to the reaction vessel. Under ice bath conditions, 10 mL of a solution of N-bromosuccinimide (0.427 g, 0.00240 mol, manufactured by Tokyo Chemical Industry Co., Ltd.) in dehydrated tetrahydrofuran was added, and the mixture was stirred for 20 minutes. After the reaction was completed, the solvent was removed by distillation of the reaction solution to obtain the crude product. The crude product was purified by silica gel column chromatography (SiO2 / hexane-hexane:chloroform = 30:1) to obtain the compound of formula (28) below as an orange solid (yield: 986 mg, yield: 77%).

[0290] <NMR Analysis Results>

[0291] 1 H-NMR (400MHz, CDCL3): δ (ppm) = 0.85 (t, 6H), 0.89-0.92 (m, 4H), 1.30-1.3 8(m, 8H), 1.48(s, 18H), 5.28(s, 1H), 7.00(s, 1H), 7.09(s, 1H), 7.39(s, 2H)

[0292]

Chemistry 51

[0293]

[0294] The compound of formula (28) above (986 mg, 1.67 mmol) and 50 mL of dehydrated tetrahydrofuran were added to the reaction vessel under an argon gas flow, and degassed by sonication for 15 minutes. A 33 wt% xylene solution (230 mg, 0.375 mmol) of bis(tributyl)tin (425 μL, 0.841 mmol, manufactured by Sigma-Aldrich), tris(dibenzylideneacetone)palladium(0) (78.5 mg, 0.0857 mmol, manufactured by Sigma-Aldrich), and tri-tert-butylphosphine (manufactured by Fujifilm and Hikari Pure Chemical Industries Co., Ltd.) was added, and the mixture was heated under reflux at 63 °C for 7 hours. The reaction solution was cooled to room temperature and allowed to stand overnight. Tris(dibenzylacetone)palladium(0) (81.3 mg, 0.0888 mmol, Sigma-Aldrich) and a 33 wt% xylene solution of tri-tert-butylphosphine (223 mg, 0.364 mmol) were added, and the mixture was heated again under reflux at 63 °C for 9 hours and 30 minutes. After the reaction was complete, the reaction solution was cooled to room temperature, and the solvent was removed by distillation to obtain the crude product.

[0295] The crude product was purified by silica gel column chromatography (SiO2 / toluene) to obtain a brownish oily substance. 50 mL of methanol was added to the brownish oily substance, and the mixture was sonicated for 60 minutes and then filtered. 10 mL of hexane was added to the filtrate, and the mixture was sonicated for 50 minutes and then filtered again to obtain a compound of formula (29) as an orange solid (yield: 285 mg, 34%).

[0296] <NMR Analysis Results>

[0297] 1 H-NMR (400MHz, THF-d8): δ (ppm) = 0.86 (t, 12H), 0.97-1.00 (m, 8H), 1.29-1.4 5(m, 16H), 1.47(s, 36H), 6.37(s, 2H), 7.20(s, 2H), 7.21(s, 2H), 7.42(s, 4H)

[0298]

Chemistry 52

[0299]

[0300] The compound of formula (29) above (31.1 mg, 0.0305 mmol), 5 mL of dehydrated 1,2-dichlorobenzene, and lead oxide (IV) (71.5 mg, 0.299 mmol) were added to the reaction vessel under an argon gas flow, and ultrasound was applied for 50 minutes. The addition of lead oxide (IV) was repeated twice, with ultrasound applied for a total of 80 minutes (additional lead oxide (IV) amount 232.8 mg, 0.973 mmol). After the reaction was complete, the reaction solution was filtered to remove lead oxide (IV), and the filtrate was distilled to remove the solvent, yielding a crude product. 5 mL of methanol was added to the crude product, and the mixture was filtered under ultrasound to obtain the compound of formula (A-27) below as a black solid (yield: 20 mg).

[0301]

Chemistry 53

[0302]

[0303] <Solubility Evaluation>

[0304] Solubility was evaluated in the same manner as in Example 2, except that (A-27) was used instead of compound (A-6). The results are shown in Table 1.

[0305] <Absorption Spectroscopy Measurement>

[0306] Except that compound (A-27) was used instead of compound (A-1), UV-Vis absorption spectroscopy measurements were performed in the same manner as in Example 1. The results are shown in Table 2.

[0307] [Comparative Example 1]

[0308] Except for replacing compound (A-6) with copper(II) phthalocyanine (β-type (manufactured by Tokyo Chemical Industry Co., Ltd.)) represented by the comparative compound (B-1) below, the solubility evaluation was performed in the same manner as in Example 1. The results are shown in Table 1.

[0309]

Chemistry 54

[0310]

[0311] [Comparative Example 2]

[0312] Solubility was evaluated in the same manner as in Example 1, except that IR-813p-toluenesulfonate (manufactured by Tokyo Chemical Industry Co., Ltd.) of the comparative compound (B-2) represented by the following formula was used instead of compound (A-6). The results are shown in Table 1.

[0313]

Transformation 55

[0314]

[0315] Table 1

[0316] compound solubility Example 2 A-6 ○ Example 3 A-35 ○ Example 4 A-27 ○ Comparative Example 1 B-1 × Comparative Example 2 B-2 ×

[0317] ○: Completely dissolved

[0318] △: Residual suspended matter

[0319] ×: Residual dissolution remains.

[0320] As shown in Table 1, the compounds of the present invention in the embodiments exhibit higher solubility compared to previously known near-infrared absorbing pigments.

[0321] Table 2

[0322]

[0323] As shown in Table 2, the compounds of the present invention exhibit a high molar absorptivity in the near-infrared region, effectively absorbing near-infrared light. Because of this effective absorption of near-infrared light, it is expected that, for example, in the fabrication of photoelectric conversion devices, devices with high conversion efficiency at low concentrations can be manufactured, thereby reducing costs. Furthermore, from Figure 1 It shows less absorption in the visible light region.

[0324] [Example 5] Evaluation of lightfastness

[0325] <Coating Preparation>

[0326] Dissolve 10 mg of near-infrared absorbing pigment (A-6) in 5 mL of polymer solution (2.5 g of polyvinyl butyral resin BM-S [Lot. IE-C50] / 25 mL of ethanol / 25 mL of toluene) to prepare a coating solution. Add 0.2 mL of the prepared coating solution dropwise onto a glass substrate (Matsunami S9111 glass slide (76×52 t 0.8~1.0)), and then spin coat the substrate using a spin coater at 500 rpm (10 sec) and 2000 rpm (30 sec) to prepare a coating film.

[0327] The prepared coating was tested using a xenon arc lamp weathering tester / ATLAS Ci3000+Xenon Weather Ometer (ATLAS), at an irradiance of 300nm–400nm and 60W / m. 2 The coating was irradiated under the following conditions: temperature in the test tank: 38℃; humidity: 50%; and temperature of the black panel (BP): 63℃. The change in absorbance at the wavelength of maximum absorption was measured using a UV-Vis spectrophotometer. The absorbance after 50 hours, 100 hours, and 150 hours of irradiation is shown in Table 3, with the absorbance at the wavelength of maximum absorption of the unirradiated coating set as 1.

[0328] [Comparative Example 3 and Comparative Example 4]

[0329] For coatings made using comparative compounds (B-1) or (B-2) instead of near-infrared absorbing pigment (A-6), lightfastness was evaluated in the same manner as in Example 5, and the results are shown in Table 3.

[0330] Table 3

[0331] pigment 50 hours later 100 hours later 150 hours later Example 5 A-6 0.72 0.40 0.25 Comparative Example 3 B-1 0.50 0.25 0.19 Comparative Example 4 B-2 0 0 0

[0332] As shown in Table 3, the compounds of the present invention exhibit higher lightfastness compared to previously known near-infrared absorbing pigments.

[0333] The compounds of this invention have good solubility and lightfastness, and can be extended to applications such as photoelectric conversion elements and color filters as near-infrared absorbing pigments.

[0334] The compounds of the present invention are expected to be used in a wide range of fields, including near-infrared absorbing pigments that have absorption in the near-infrared region, high solubility in solvents, film-forming properties based on solution processes, and high lightfastness; photoelectric conversion elements such as solar cells and near-infrared light sensors; near-infrared absorbing materials such as neutral density (ND) filters, color filters, near-infrared absorbing materials for safety applications, agricultural films, dimming filters (thermal insulation, semiconductor sensors), and photosensitive pigments for photodynamic therapy.

Claims

1. A compound represented by the following general formula (1), ###0001### (1) 【Chemical Formula 1】 wherein R 1 ~R 4 each independently, and represent a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, a sec-butyl group, a t-butyl group, an n-pentyl group, an i-pentyl group, an n-hexyl group, a 2-ethylhexyl group, a heptyl group, an octyl group, an i-octyl group, a nonyl group, or a decyl group, X 1 and X 2 represents a divalent group represented by the following general formula (2) or general formula (3), 【Chemical Formula 2】 wherein R 5 and R 6 are each independently and represent a linear or branched alkyl group having 1 to 20 carbon atoms which can have a substituent, a cycloalkyl group having 3 to 10 carbon atoms which can have a substituent, or a phenyl group, a naphthyl group, a biphenyl group which can have a substituent, Y represents a carbon atom or a silicon atom, 【Chemical Formula 3】 wherein Z represents an oxygen atom, CR 7 R 8 or NR 9 , R 7 and R 8 are each independently and represent a nitrile group, an acyl group having 1 to 18 carbon atoms which can have a substituent, or an alkoxycarbonyl group having 1 to 18 carbon atoms which can have a substituent, R 9 represents a linear or branched alkyl group having 1 to 20 carbon atoms which can have a substituent, a cycloalkyl group having 3 to 10 carbon atoms which can have a substituent, or a phenyl group, a naphthyl group, a biphenyl group which can have a substituent.

2. The compound of claim 1, wherein, In the general formula (1), R 1 ~R 4 is a tert-butyl group.

3. A near-infrared absorbing dye comprising the compound according to claim 1.

4. A thin film comprising the compound according to claim 1.

5. A color filter comprising the near-infrared absorbing dye according to claim 3.

6. A near-infrared cut filter comprising the near-infrared absorbing dye according to claim 3.

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