JP2014088323A - Alkyne derivative and application thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compound useful as a photoelectric conversion dye excellent in photoelectric conversion characteristics.SOLUTION: There are provided: an alkyne derivative represented by general formula (1); a tautomer or stereoisomer of the alkyne derivative; and salts thereof. In the formula (1), D represents an organic group containing an electron-donating substituent; X represents a group having an acidic group; and Z represents a linking group having at least one heterocyclic ring selected from the group consisting of a thiophene ring, a furan ring, and a pyrrole ring.

Description

  The present invention relates to alkyne derivatives and uses thereof.

Due to the large amount of fossil fuels represented by petroleum so far, global warming has become a serious problem due to the increase in CO ₂ concentration, and there is a concern about the depletion of fossil fuels. Therefore, how to meet future demand for large amounts of energy has become a very important issue on a global scale. Under such circumstances, the use of light energy that is infinite and clean with respect to nuclear power generation is being actively studied. Solar cells that convert light energy into electrical energy include inorganic solar cells that use inorganic materials such as single crystal silicon, polycrystalline silicon, and amorphous silicon, and organic solar cells that use organic dyes and conductive polymer materials. Solar cells have been proposed.

  Under such circumstances, a dye-sensitized solar cell (Gretzel solar cell) (for example, see Patent Document 1 and Non-Patent Document 1) proposed by Dr. Gretzell of Switzerland in 1991 is a simple manufacturing process. In addition, since conversion efficiency similar to amorphous silicon is obtained, it is expected as a next-generation solar cell. A Gretzel type solar cell includes a semiconductor electrode in which a semiconductor layer having a dye adsorbed thereon is formed on a conductive substrate, a counter electrode made of a conductive substrate opposite to the electrode, and an electrolyte layer held between the electrodes. And.

  In this Gretzel type solar cell, the adsorbed dye absorbs light and enters an excited state, and electrons are injected from the excited dye into the semiconductor layer. The dye that is in an oxidized state due to the emission of electrons returns to the original dye by transferring electrons to the dye by the oxidation reaction of the redox agent in the electrolyte layer. Then, the redox agent that has donated electrons to the dye is reduced again on the counter electrode side. The Gretzel type solar cell functions as a battery by this series of reactions.

  In this Gretzel type solar cell, the effective reaction surface area increased about 1000 times by using porous titanium oxide in which fine particles were sintered in the semiconductor layer, and a photocurrent larger than the conventional one could be taken out. It is a big feature.

  In a Gretzel type solar cell, a metal complex such as a ruthenium complex is used as a sensitizing dye. Specifically, for example, cis-bis (isothiocyanato) -bis- (2,2′-bipyridyl-4,4′-dicarboxylic acid) is used. Acid) ruthenium (II) ditetrabutylammonium complex, cis-bis (isothiocyanato) -bis- (2,2′-bipyridyl-4,4′-dicarboxylic acid) ruthenium (II), etc. Tris (isothiocyanato) (2,2 ′: 6 ′, 2 ″ -terpyridyl-4,4 ′, 4 ″ -tricarboxylic acid) ruthenium (II) tritetrabutylammonium complex, which is a kind of complex, is used.

Japanese Patent No. 2664194

Nature 353 (1991) 737-740.

  As described above, a metal complex containing a noble metal such as ruthenium is used in the dye-sensitized solar cell of the related art. However, there is a possibility that a problem may occur in terms of resource limitation when mass production is performed. . In addition, the solar cell becomes expensive and hinders its spread. For this reason, development of the organic dye which does not contain noble metals, such as ruthenium, is calculated | required as a sensitizing dye in a dye-sensitized solar cell. In general, organic dyes have a higher molar extinction coefficient than metal complexes such as ruthenium complexes, and further have a high degree of freedom in molecular design, so that development of dyes with high photoelectric conversion efficiency is expected.

  The present invention has been made to solve the above-mentioned problems, and is an alkyne derivative that can be used as a photoelectric conversion dye excellent in photoelectric conversion characteristics, and a photoelectric conversion excellent in photoelectric conversion characteristics including the alkyne derivative. It is providing the pigment | dye, the semiconductor electrode for photoelectrochemical cells using the same, the photoelectric conversion element for photoelectrochemical cells, and a photoelectrochemical cell.

The compound of the present invention is an alkyne derivative represented by the following general formula (1), a tautomer or stereoisomer thereof, or a salt thereof.

In the formula (1),
D represents an organic group containing an electron-donating substituent,
X represents a group having an acidic group,
Z represents a linking group having at least one heterocyclic ring selected from the group consisting of a thiophene ring, a furan ring and a pyrrole ring.

  The photoelectric conversion dye of the present invention includes at least one of the alkyne derivative of the present invention, a tautomer or stereoisomer thereof, or a salt thereof.

  The semiconductor electrode for photoelectrochemical cells of the present invention is characterized by having a semiconductor layer containing the photoelectric conversion dye of the present invention.

  The photoelectric conversion element for a photoelectrochemical cell of the present invention has the semiconductor electrode for a photoelectrochemical cell of the present invention.

  Moreover, the photoelectrochemical cell of the present invention is characterized by having the photoelectric conversion element for a photoelectrochemical cell of the present invention.

  ADVANTAGE OF THE INVENTION According to this invention, the alkyne derivative which can be used for the pigment | dye for photoelectric conversion excellent in the photoelectric conversion characteristic, the photoelectric conversion pigment | dye excellent in the photoelectric conversion characteristic containing the said alkyne derivative, and a semiconductor for photoelectrochemical cells using the same An electrode, a photoelectric conversion element for a photoelectrochemical cell, and a photoelectrochemical cell can be provided.

It is sectional drawing which shows typically the structure of an example of the photoelectric conversion element for photoelectrochemical cells of this invention. 1 is a graph showing an absorption spectrum curve of an alkyne derivative (TA-1) of Example 1. FIG. It is a figure which shows the absorption spectrum curve of the alkyne derivative (TA-2) of Example 2.

  Hereinafter, the present invention will be described in detail with reference to examples.

<Alkyne derivatives>
As described above, the compound of the present invention is an alkyne derivative represented by the following general formula (1), a tautomer or stereoisomer thereof, or a salt thereof.

In the general formula (1),
D represents an organic group containing an electron-donating substituent,
X represents a group having an acidic group,
Z represents a linking group having at least one heterocyclic ring selected from the group consisting of a thiophene ring, a furan ring and a pyrrole ring.

  When the alkyne derivative of the present invention has isomers such as tautomers or stereoisomers (eg, geometric isomers, conformational isomers and optical isomers), any isomers are included in the present invention. Can be used. The salt of the alkyne derivative of the present invention may be an acid addition salt or a base addition salt. Furthermore, the acid forming the acid addition salt may be an inorganic acid or an organic acid, and the base forming the base addition salt may be an inorganic base or an organic base. The inorganic acid is not particularly limited. For example, sulfuric acid, phosphoric acid, hydrofluoric acid, hydrochloric acid, hydrobromic acid, hydroiodic acid, hypofluorite, hypochlorous acid, hypobromite, Hypoiodous acid, fluorinated acid, chlorous acid, bromic acid, iodic acid, fluoric acid, chloric acid, bromic acid, iodic acid, perfluoric acid, perchloric acid, perbromic acid, periodic acid, etc. Can be mentioned. The organic acid is not particularly limited, and examples thereof include p-toluenesulfonic acid, methanesulfonic acid, oxalic acid, p-bromobenzenesulfonic acid, carbonic acid, succinic acid, citric acid, benzoic acid, and acetic acid. The inorganic base is not particularly limited, and examples thereof include ammonium hydroxide, alkali metal hydroxides, alkaline earth metal hydroxides, carbonates and hydrogen carbonates, and more specifically, for example, Examples thereof include sodium hydroxide, potassium hydroxide, potassium carbonate, sodium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, calcium hydroxide and calcium carbonate. The organic base is not particularly limited, and examples thereof include alcohol amine, trialkylamine, tetraalkylammonium, and tris (hydroxymethyl) aminomethane. Examples of the alcohol amine include ethanolamine. Examples of the trialkylamine include trimethylamine, triethylamine, tripropylamine, tributylamine, and trioctylamine. Examples of the tetraalkylammonium include tetramethylammonium, tetraethylammonium, tetrapropylammonium, tetrabutylammonium, tetraoctylammonium and the like. The method for producing these salts is not particularly limited, and for example, the salt can be produced by a method such as appropriately adding the above acid or base to the alkyne derivative by a known method.

  Moreover, in this invention, carbon number of an alkyl group is 1-12, for example, Preferably it is 1-8, and carbon number of an aryl group is 5-24, for example, Preferably it is 6-12. In the case of a substituted alkyl group or a substituted aryl group, the number of carbon atoms does not include the number of carbon atoms of the substituent. In the present invention, the alkyl group specifically includes, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, Examples include hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group and the like. The same applies to a group containing an alkyl group in the structure (alkylamino group, alkoxy group, alkanoyl group, etc.). In the present invention, the substituted alkyl group may be a substituted alkyl group in which the alkyl group (unsubstituted alkyl group) is substituted with an arbitrary substituent. One or a plurality of substituents of the substituted alkyl group may be used, and when there are a plurality of substituents, they may be the same or different. Examples of the substituent of the substituted alkyl group include a hydroxy group, an alkoxy group, an aryl group (for example, a phenyl group) and the like. Specific examples of the substituted alkyl group include araalkyl groups such as a benzyl group.

In the present invention, the aryl group includes a heteroaryl group unless specifically limited, and specifically includes, for example, a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group, a pyrenyl group, a pyridyl group, a quinolyl group, and an acridyl group. , Pyrenyl group, furanyl group, thienyl group, carbazoyl group, fluorenyl group and the like. In the present invention, the substituted aryl group may be a substituted aryl group in which the aryl group (unsubstituted aryl group) is substituted with an arbitrary substituent. One or a plurality of substituents of the substituted aryl group may be used, and when there are a plurality of substituents, they may be the same or different. Examples of the substituent of the substituted aryl group include an alkyl group, a hydroxy group, an alkoxy group, an amino group, an alkylamino group, and a dialkylamino group. Specific examples of the substituted or unsubstituted aryl group in the present invention include a phenyl group, tolyl group, 4-t-butylphenyl group, 3,5-di-t-butylphenyl group, and 4-methoxyphenyl. Group, 4- (N, N-dimethylamino) phenyl group, 4-hexyloxyphenyl group, 4-octyloxyphenyl group, 4- (α, α-dimethylbenzyl) phenyl group, and 9,9-dimethylfluorene And 2-yl group.

  In the present invention, the alkenyl group may have a structure in which any carbon-carbon bond of the alkyl group is converted to a double bond by dehydrogenation. In the present invention, the acyl group is not particularly limited. For example, formyl group, acetyl group, propionyl group, isobutyryl group, valeryl group, isovaleryl group, pivaloyl group, hexanoyl group, cyclohexanoyl group, benzoyl group, ethoxycarbonyl The same applies to groups containing an acyl group in the structure (acyloxy group, alkanoyloxy group, etc.). In the present invention, the carbon number of the acyl group includes carbonyl carbon. For example, an alkanoyl group having 1 carbon atom (acyl group) refers to a formyl group. In the present invention, “halogen” refers to any halogen element, and examples thereof include fluorine, chlorine, bromine and iodine.

  In the present invention, a chain group such as an alkyl group, an alkoxy group, an alkenyl group, and an alkanoyl group may be linear or branched unless otherwise limited. In the present invention, when an isomer is present in a substituent or the like, any isomer may be used unless otherwise limited. For example, when simply referring to a “propyl group”, either an n-propyl group or an isopropyl group may be used. When simply referred to as “butyl group”, any of n-butyl group, isobutyl group, sec-butyl group and tert-butyl group may be used. When simply referred to as “naphthyl group”, either a 1-naphthyl group or a 2-naphthyl group may be used.

  D in the general formula (1) represents an organic group containing an electron-donating substituent as described above. The organic group D containing an electron donating substituent is preferably a group represented by the following general formula (5).

In the formula (5), Ar ¹ and Ar ² each independently represent a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group or a heterocyclic group. Examples of the substituted or unsubstituted alkyl group include a methyl group, an ethyl group, a propyl group, an n-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, etc., an alkyl group having 1 to 8 carbon atoms, a benzyl group, etc. Examples of the substituent bonded to the alkyl group include a hydroxy group, an alkoxy group (for example, an alkoxy group having 1 to 4 carbon atoms), a phenyl group, and the like. Examples of the substituted or unsubstituted aryl group include phenyl group, tolyl group, 4-t-butylphenyl group, 3,5-di-t-butylphenyl group, 4-methoxyphenyl group, 4-hexyloxyphenyl group, 4 -Octyloxyphenyl group, 4- (N, N-dimethylamino) phenyl group, 4- (N, N-diphenylamino) phenyl group, 4- (α, α-dimethylbenzyl) phenyl group, 9,9-dimethyl Examples include a substituted or unsubstituted aryl group having 6 to 22 carbon atoms such as a fluoren-2-yl group. Examples of the substituent bonded to the aryl group include an alkyl group (for example, an alkyl group having 1 to 8 carbon atoms), hydroxy Group, an alkoxy group (for example, an alkoxy group having 1 to 8 carbon atoms), an N, N-dialkylamino group (the alkyl group portion is, for example, an alkyl group having 1 to 8 carbon atoms), N, N- A diphenylamino group etc. are mentioned. Examples of the substituted or unsubstituted heterocyclic group include a thienyl group, a furyl group, a pyrrolyl group, an indolyl group, a carbazoyl group, and the like. Examples of the substituent bonded to the heterocyclic group include an alkyl group (for example, having 1 to 8 carbon atoms). Alkyl group), a hydroxy group, an alkoxy group (for example, an alkoxy group having 1 to 8 carbon atoms) and the like. Ar ³ represents a substituted or unsubstituted arylene group or a substituted or unsubstituted divalent heterocyclic group. Examples of the substituted or unsubstituted arylene group include a phenylene group and a naphthylene group. Examples of the substituent bonded to the arylene group include an alkyl group (for example, an alkyl group having 1 to 8 carbon atoms), a hydroxy group, and an alkoxy group ( For example, a C1-C8 alkoxy group) etc. are mentioned. Examples of the substituted or unsubstituted divalent heterocyclic group include a thiophene diyl group, a furandiyl group, a pyrrole diyl group, and the like, and examples of the substituent bonded to the divalent heterocyclic ring include an alkyl group (for example, having a carbon number of 1 to 8 alkyl group), a hydroxy group, an alkoxy group (for example, an alkoxy group having 1 to 8 carbon atoms) and the like.

  Specific examples of the organic group D containing the electron donating substituent other than the group represented by the general formula (5) are shown in the following chemical formulas (D1) to (D9), but are not limited thereto. Absent. Note that R in the following chemical formulas (D3) to (D6) and (D9) is a carbon number of 1 such as a methyl group, an ethyl group, a propyl group, an n-butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. Represents an alkyl group of ˜8.

  X in the general formula (1) represents a group having an acidic group as described above. X may consist of only an acidic group, or may be a group in which an acidic group is bonded to another group. X is preferably an organic group having an acidic group. For example, the other group to which the acidic group is bonded may be an organic group. The organic group is not particularly limited, but is preferably a group that can be conjugated with Z. The group capable of conjugating with Z is more preferably a group having a carbon-carbon double bond. Examples of the acidic group include a carboxy group, a sulfonic acid group, a phosphonic acid group, or a salt thereof, and a carboxy group or a salt thereof is particularly preferable. When the acidic group is a salt, a monovalent or divalent metal salt, ammonium salt or organic ammonium salt is preferable. Examples of the monovalent or divalent metal salt include alkali metal salts such as Li, Na, K, and Cs, and alkaline earth metal salts such as Mg, Ca, and Sr. Examples of the organic group of the organic ammonium salt include an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 1 to 8 carbon atoms, and an aryl group having 6 to 12 carbon atoms.

  The alkyne derivative represented by the general formula (1) can be adsorbed on a semiconductor layer used in a semiconductor electrode for a photoelectrochemical cell to be described later because X has an acidic group.

  Specific examples of the organic group X having an acidic group are shown in the following chemical formulas (Xa) to (Xm). These organic groups X have an intercarbon (carbon-carbon) double bond in addition to an acidic group, and one bond of the linking group Z is bonded to one carbon of the carbon-carbon double bond, and the other A cyano group, carbonyl group, carbon of another carbon-carbon double bond, or carbon of carbon-nitrogen double bond is bonded to the carbon of. However, the organic group X is not limited to these. Further, the organic group X represented by the chemical formulas (Xa) to (Xm) may be either Z-form or E-form. That is, these organic groups X may have structures as represented by chemical formulas (Xa) to (Xm) or geometric isomers thereof.

In the formulas (Xa) to (Xm),
M represents a hydrogen atom or a salt-forming cation,
B ⁻ represents a hydroxide ion or a salt-forming anion.
M and B ⁻ may be monovalent ions or multivalent ions. When M or B ⁻ is a multivalent ion, the number in the above formulas (Xa) to (Xm) may be a fraction of the valence. For example, M may be 1 / 2Mg ²⁺ and B ⁻ may be 1 / 2SO ₄ ²⁻ , but is not limited thereto.

Examples of the salt-forming cation M include various cations capable of forming a salt with a carboxy group. Examples of such a cation include an ammonium cation (NH ₄ ⁺ ); an organic ammonium cation derived from an amine (A ¹ A ² A ³ A ⁴ N ⁺ , A ^{1 to} A ⁴ are a hydrogen atom or an organic group. At least one of which is an organic group); alkaline metal ions such as Li ⁺ , Na ⁺ , K ⁺ and Cs ⁺ ; alkaline earth metal ions such as Mg ²⁺ , Ca ²⁺ and Sr ^2+, etc. . Examples of the organic group of the organic ammonium cation include an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 1 to 8 carbon atoms, and an aryl group having 6 to 12 carbon atoms.

  The organic group X having an acidic group is more preferably represented by the following chemical formulas (X1) to (X16). Further, the organic group X represented by the chemical formulas (X1) to (X16) may be either Z-form or E-form. That is, these organic groups X may have structures as represented by chemical formulas (X1) to (X16) or geometric isomers thereof.

前記一般式（２）中、Ｍは、水素原子または塩形成性陽イオンを表し、前記式（Ｘａ）〜（Ｘｍ）中のＭと同様である。 The organic group X is more preferably a group represented by the following general formula (2).

In the general formula (2), M represents a hydrogen atom or a salt-forming cation, and is the same as M in the formulas (Xa) to (Xm).

Z in the general formula (1) represents a linking group having at least one heterocyclic ring selected from a thiophene ring, a furan ring and a pyrrole ring. The linking group Z is not particularly limited, but is preferably an atomic group that can be conjugated with a carbon-carbon triple bond to which Z is bonded (that is, —C≡C— shown in the general formula (1)). The linking group Z is preferably a linking group having a structure represented by at least the following general formula (3).

In the general formula (3), R ¹ and R ² each independently represent a hydrogen atom, a substituted or unsubstituted linear or branched alkyl group, or a substituted or unsubstituted linear or branched alkoxy group, R ¹ and R ² may be connected to each other to form a ring. Examples of the substituted or unsubstituted alkyl group include alkyl groups having 1 to 8 carbon atoms such as a methyl group, an ethyl group, a propyl group, an n-butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. Examples of the substituent bonded to the group include a hydroxy group and an alkoxy group. As an alkoxy group, C1-C4 alkoxy groups, such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, are mentioned.

  In the general formula (3), Y represents an oxygen atom, a sulfur atom or NRa, and Ra represents a hydrogen atom, a substituted or unsubstituted linear or branched alkyl group, or a substituted or unsubstituted aryl group. Examples of the substituted or unsubstituted alkyl group include a methyl group, an ethyl group, a propyl group, an n-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, etc., an alkyl group having 1 to 8 carbon atoms, a benzyl group, etc. Examples of the substituent bonded to the alkyl group include a hydroxy group, an alkoxy group (for example, an alkoxy group having 1 to 4 carbon atoms), a phenyl group, and the like. Examples of the substituted or unsubstituted aryl group include phenyl group, tolyl group, 4-t-butylphenyl group, 3,5-di-t-butylphenyl group, 4-methoxyphenyl group, 4- (N, N-dimethyl group). Examples thereof include substituted or unsubstituted aryl groups having 6 to 22 carbon atoms such as amino) phenyl group. Examples of the substituent bonded to the aryl group include an alkyl group (for example, an alkyl group having 1 to 8 carbon atoms), a hydroxy group, an alkoxy group (for example, an alkoxy group having 1 to 4 carbon atoms), and an N, N-dialkylamino group. (The alkyl group moiety is, for example, an alkyl group having 1 to 8 carbon atoms).

  Specific examples of the linking group Z are shown in the chemical formulas (Z1) to (Z24), but are not limited thereto. These examples are divalent groups having a bond in the heterocycle, and when there are multiple heterocycles, the carbons that make up the heterocycle are directly bonded to each other, or are bonded by forming a condensed ring. . Further, a group in which a plurality of these linking groups are linked may be used.

  Moreover, as a combination of X and Z in the alkyne derivative represented by the general formula (1), a tautomer or stereoisomer thereof, or a salt thereof, for example, the following (am)-(1 24). In the following table, Xa may be replaced with X1 to X4, Xb may be replaced with X5, Xc may be replaced with X6, Xd may be replaced with X7, and Xe may be replaced with X8. , Xf may be replaced with X9, Xg may be replaced with X10, Xh may be replaced with X11, Xi may be replaced with X12, Xj may be replaced with X13, and Xk may be replaced with X14. Xl may be replaced with X15, and Xm may be replaced with X16.

In the alkyne derivative represented by the general formula (1), a tautomer or stereoisomer thereof, or a salt thereof, an organic group D containing an electron donating substituent is represented by the formula (5) , Ar ^{1 to} Ar ³ include, for example, the following Ar-1 to Ar-16. The following Ar- ^{1 to} Ar-16 show combinations in which Ar ¹ and Ar ² are the same atomic group, but are not limited thereto, and Ar ¹ and Ar ² may be different.

The alkyne derivative of the present invention is more preferably an alkyne derivative represented by the following general formula (4).

In the general formula (4), Ar ¹ and Ar ² each independently represent a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group. Examples of the substituted or unsubstituted alkyl group include a methyl group, an ethyl group, a propyl group, an n-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, etc., an alkyl group having 1 to 8 carbon atoms, a benzyl group, etc. Examples of the substituent bonded to the alkyl group include a hydroxy group, an alkoxy group (for example, an alkoxy group having 1 to 4 carbon atoms), a phenyl group, and the like. Examples of the substituted or unsubstituted aryl group include phenyl group, tolyl group, 4-t-butylphenyl group, 3,5-di-t-butylphenyl group, 4-methoxyphenyl group, 4-hexyloxyphenyl group, 4 -Octyloxyphenyl group, 4- (N, N-dimethylamino) phenyl group, 4- (N, N-diphenylamino) phenyl group, 4- (α, α-dimethylbenzyl) phenyl group, 9,9-dimethyl Examples include a substituted or unsubstituted aryl group having 6 to 22 carbon atoms such as a fluoren-2-yl group. Examples of the substituent bonded to the aryl group include an alkyl group (for example, an alkyl group having 1 to 8 carbon atoms), hydroxy Group, an alkoxy group (for example, an alkoxy group having 1 to 8 carbon atoms), an N, N-dialkylamino group (the alkyl group portion is, for example, an alkyl group having 1 to 8 carbon atoms), N, N- A diphenylamino group etc. are mentioned. Examples of the substituted or unsubstituted heterocyclic group include a thienyl group, a furyl group, a pyrrolyl group, an indolyl group, a carbazoyl group, and the like. Examples of the substituent bonded to the heterocyclic group include an alkyl group (for example, having 1 to 8 carbon atoms). Alkyl group), a hydroxy group, an alkoxy group (for example, an alkoxy group having 1 to 8 carbon atoms) and the like. Ar ³ represents a substituted or unsubstituted arylene group or a substituted or unsubstituted divalent heterocyclic group. Examples of the substituted or unsubstituted arylene group include a phenylene group and a naphthylene group. Examples of the substituent bonded to the arylene group include an alkyl group (for example, an alkyl group having 1 to 8 carbon atoms), a hydroxy group, and an alkoxy group ( For example, a C1-C8 alkoxy group) etc. are mentioned. Examples of the substituted or unsubstituted divalent heterocyclic group include a thiophene diyl group, a furandiyl group, a pyrrole diyl group, and the like, and examples of the substituent bonded to the divalent heterocyclic ring include an alkyl group (for example, having a carbon number of 1 to 8 alkyl group), a hydroxy group, an alkoxy group (for example, an alkoxy group having 1 to 8 carbon atoms) and the like.

  M in the general formula (4) represents a hydrogen atom or a salt-forming cation, and is the same as M in the formulas (Xa) to (Xm).

  Moreover, Z in the said General formula (4) is the same as Z in the said General formula (1), Preferably, the linking group containing the structure represented by the said General formula (3) is represented.

The compound of the present invention is particularly preferably an alkyne derivative represented by the following formula TA-1, a tautomer or stereoisomer thereof, or a salt thereof.

The compound of the present invention is also particularly preferably an alkyne derivative represented by the following formula TA-2, a tautomer or stereoisomer thereof, or a salt thereof.

  In addition to the compounds TA-1 and TA-2, for example, compounds TA-3 to TA-6 shown in Table 7 below are particularly preferable. In the following Table 7, the structures of the compounds TA-3 to TA-6 are shown by combinations of D, X and Z in the formula (1). In addition, these compounds TA-3 to TA-6 can be obtained by referring to the production methods and examples described below, and without any undue trial and error or complicated advanced experiments by those skilled in the art. It can be easily produced and used according to 1 or TA-2. In addition, you may substitute the combination of X and Z in each of compound TA-1 to TA-6 of following Table 7 with either of the combinations of X and Z in the said Tables 1-5, for example. Moreover, the compound of this invention is not limited to these examples, The combination of D, X, and Z is arbitrary, for example, arbitrary combinations of the said Tables 1-5, said (D1)-(D9), Can be combined with each other. For example, when D is represented by the formula (5), any combination of Tables 1 to 5 and any combination of Table 6 can be combined.

  In the alkyne derivative of the present invention, a tautomer or stereoisomer thereof, or a salt thereof, an organic group containing an electron-donating substituent and a linking group are linked by a carbon-carbon triple bond (—C≡C—). It has the structure. The dissociation energy of the carbon-carbon triple bond is 956.6 kJ / mol, which is larger than the dissociation energy of the carbon-carbon double bond (—C═C—), 719 kJ / mol (described in Chemistry Handbook, Volume II, p317). Therefore, it can be expected that the organic group containing an electron-donating substituent and the linking group are linked by a carbon-carbon triple bond, rather than being linked by a carbon-carbon double bond, to provide a dye having excellent thermal stability. Further, it is known that a compound having a carbon-carbon double bond generally causes cis-trans isomerization by light, and a dye having a carbon-carbon double bond is considered to have a problem in light resistance. However, a carbon-carbon triple bond such as the alkyne derivative of the present invention does not cause such an isomerization reaction, so that it can be a dye having more excellent light resistance.

  The alkyne derivative of the present invention, its tautomer or stereoisomer, or a salt thereof is useful for, for example, a photoelectric conversion dye excellent in photoelectric conversion characteristics, but is not limited thereto, and any use is possible. You may use for.

<Method for producing alkyne derivative>
The production method of the alkyne derivative represented by the general formula (1), a tautomer or stereoisomer thereof, or a salt thereof is not particularly limited, and is arbitrary. For example, the production method shown in the following scheme But you can. Specifically, the following scheme:
The 1st coupling process which manufactures the compound represented by the following general formula (III) by the coupling reaction of the compound represented by the following general formula (I), and the compound represented by the following general formula (II) ,
A deprotection step for producing a compound represented by the following general formula (IV) by deprotecting the compound represented by the following general formula (III);
A second coupling step in which a compound represented by the following general formula (IV) and a compound represented by the following general formula (V) are subjected to a coupling reaction to produce a compound represented by the following general formula (VI); and,
It includes an acidic group introduction step of converting the Q ² in the following general formula (VI) to introduce an acidic group X to produce the compound represented by the general formula (1).

In the general formulas (I), (III), (IV) and (VI),
D is the same as the general formula (1),
In the general formulas (II) and (III),
Q ¹ is a protecting group,
In the general formula (I),
Hal ¹ is halogen,
In the general formula (V),
Hal ² is halogen,
Hal ¹ and Hal ² may be the same or different,
In the general formulas (V) and (VI),
Z is the same as the general formula (1),
Q ² is an arbitrary substituent that can be converted to the acidic group X.

  In the first coupling step, the deprotection step, the second coupling step, and the acidic group introduction step, the reaction time, the reaction temperature, the amount of each reactant used, etc. are not particularly limited. You may set suitably with reference to a similar reaction etc. In each of the steps, a solvent, a catalyst, or the like may be appropriately used in addition to the reactants, or may not be used.

Hal ¹ and Hal ² are not particularly limited, but chlorine, bromine or iodine are preferable, and bromine or iodine is more preferable from the viewpoint of reactivity. The first coupling step and the second coupling step are preferably performed in the presence of a palladium catalyst and a base, respectively, and may be performed in the presence of a copper catalyst. Such a coupling reaction is sometimes called, for example, Sonogashira coupling.

前記一般式（VII）および（VIII）中、
Ｒ^１０は、水素原子、置換若しくは無置換のアルキル基、または置換若しくは無置換のアリール基であり、
前記一般式（VIII）中、
−ＣＯＯＨのＨは、例えば、前記一般式（２）と同じＭで置換してもよい。 In the general formulas (V) and (VI),
Q ² is an acyl group represented by the following general formula (VII),
In the general formula (I),
X is an acidic group represented by the following general formula (VIII),
In the acidic group introduction step, Q ² is preferably converted to X by reacting Q ² with cyanoacetic acid.

In the general formulas (VII) and (VIII),
R ¹⁰ is a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group,
In the general formula (VIII),
For example, H in —COOH may be substituted with the same M as in the general formula (2).

<Dye for photoelectric conversion>
The photoelectric conversion dye of the present invention contains at least one of the alkyne derivative of the present invention, a tautomer or stereoisomer thereof, or a salt thereof. The said compound etc. are useful as a pigment | dye for photoelectric conversion excellent in the photoelectric conversion characteristic.

<Photoelectric conversion element for photoelectrochemical cell>
FIG. 1 schematically shows a cross-sectional structure of an example of the photoelectric conversion element for a photoelectrochemical cell of the present invention. The photoelectric conversion element shown in FIG. 1 includes a semiconductor electrode 4 for a photoelectrochemical cell, a counter electrode 8, and an electrolyte layer (charge transport layer) 5 held between both electrodes. The semiconductor electrode 4 for photoelectrochemical cells includes a conductive substrate including a light transmissive substrate 3 and a transparent conductive layer 2, and a semiconductor layer 1. The counter electrode 8 includes a catalyst layer 6 and a substrate 7. The semiconductor layer 1 is adsorbed with the photoelectric conversion dye.

  When light is incident on the photoelectric conversion element for photoelectrochemical cell, the photoelectric conversion dye adsorbed on the semiconductor layer 1 is excited and emits electrons. The electrons move to the conduction band of the semiconductor, and further move to the transparent conductive layer 2 by diffusion. The electrons in the transparent conductive layer 2 move to the counter electrode 8 via an external circuit (not shown). Then, the photoelectric conversion dye (oxidized dye) that has released the electrons receives (reduced) electrons from the electrolyte layer 5, returns to the original state, and the photoelectric conversion dye is regenerated. On the other hand, the electrons moved to the counter electrode are given to the electrolyte layer 5 and the electrolyte is reduced. In this manner, the photoelectric conversion element functions as a battery. Hereinafter, each component will be described by taking the photoelectric conversion element for a photoelectrochemical cell shown in FIG. 1 as an example.

<Semiconductor electrode for photoelectrochemical cell>
The semiconductor electrode 4 for photoelectrochemical cells includes the conductive substrate including the light transmissive substrate 3 and the transparent conductive layer 2 and the semiconductor layer 1 as described above. As shown in FIG. 1, a light transmissive substrate 3, a transparent conductive layer 2, and a semiconductor layer 1 are laminated in this order from the outside to the inside of the element. The semiconductor layer 1 is adsorbed with a dye for photoelectric conversion (not shown).

<Conductive substrate>
The conductive substrate constituting the semiconductor electrode 4 for photoelectrochemical cells may have a single-layer structure in which the substrate itself has conductivity, or a two-layer structure in which a conductive layer is formed on the substrate. Also good. The conductive substrate of the photoelectric conversion element for a photoelectrochemical cell shown in FIG. 1 has a two-layer structure in which a transparent conductive layer 2 is formed on a light transmissive substrate 3.

  Examples of the substrate used for the conductive substrate include a glass substrate, a plastic substrate, and a metal plate. Among them, a substrate having high light transmittance, for example, a transparent plastic substrate is particularly preferable. Examples of the material for the transparent plastic substrate include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), polycycloolefin, and polyphenylene sulfide.

Further, the conductive layer (for example, the transparent conductive layer 2) formed on the substrate (for example, the light transmissive substrate 3) is not particularly limited, but for example, indium tin oxide (Indium-Tin-Oxide: ITO), A transparent conductive layer made of a transparent material such as fluorine-doped tin oxide (FTO), indium-zinc oxide (IZO), tin oxide (SnO ₂ ), or the like is preferable. The conductive layer formed over the substrate can be formed into a film shape over the entire surface or a part of the surface of the substrate. The thickness of the conductive layer can be selected as appropriate, but is preferably about 0.02 μm to 10 μm. Such a conductive layer can be formed using a normal film formation technique.

  The conductive substrate in the present embodiment can be provided with a metal lead wire for the purpose of reducing the resistance of the conductive substrate. Examples of the material of the metal lead wire include metals such as aluminum, copper, gold, silver, platinum, and nickel. The metal lead wire can be produced by vapor deposition, sputtering, or the like. After a metal lead wire is formed on the substrate (for example, the light-transmitting substrate 3), a conductive layer (for example, a transparent conductive layer 2 such as ITO or FTO) can be provided on the metal lead wire. Alternatively, after providing a conductive layer (for example, transparent conductive layer 2) on a substrate (for example, light transmissive substrate 3), a metal lead wire may be formed on the conductive layer.

  The description of the following embodiment is based on an example in which a conductive substrate having a two-layer structure in which a transparent conductive layer 2 is formed on a light transmissive substrate 3 is used as the conductive substrate in the semiconductor electrode 4 for a photoelectrochemical cell. Although described, the present invention is not limited to this example.

<Semiconductor layer>
As a material constituting the semiconductor layer 1, a single semiconductor such as silicon or germanium, a compound semiconductor such as a metal chalcogenide, a compound having a perovskite structure, or the like can be used.

  Metal chalcogenides include oxides such as titanium, tin, zinc, iron, tungsten, indium, zirconium, vanadium, niobium, tantalum, strontium, hafnium, cerium, lanthanum; cadmium, zinc, lead, silver, antimony, bismuth, etc. Sulfides; selenides such as cadmium and lead; tellurides of cadmium and the like. Examples of other compound semiconductors include phosphides such as zinc, gallium, indium and cadmium; gallium arsenide; copper-indium-selenide; copper-indium-sulfide. Examples of the compound having a perovskite structure include commonly known semiconductor compounds such as barium titanate, strontium titanate, and potassium niobate. These semiconductor materials can be used alone or in combination of two or more.

  Among these semiconductor materials, from the viewpoint of conversion efficiency, stability, and safety, a semiconductor material containing titanium oxide or zinc oxide is preferable, and a semiconductor material containing titanium oxide is more preferable. Examples of titanium oxide include various types of titanium oxide such as anatase type titanium oxide, rutile type titanium oxide, amorphous titanium oxide, metatitanic acid, orthotitanic acid, and a titanium oxide-containing complex can be used. . Among these, anatase type titanium oxide is preferable from the viewpoint of further improving the stability of photoelectric conversion.

  Examples of the form of the semiconductor layer include a porous semiconductor layer obtained by sintering semiconductor fine particles, a thin film semiconductor layer obtained by a sol-gel method, a sputtering method, a spray pyrolysis method, and the like. Moreover, it is good also as a semiconductor layer which consists of a fibrous semiconductor layer or an acicular crystal | crystallization. The form of these semiconductor layers can be appropriately selected according to the purpose of use of the photoelectric conversion element. Among these, a semiconductor layer having a large specific surface area such as a porous semiconductor layer and a needle-like semiconductor layer is preferable from the viewpoint of the amount of dye adsorbed. Furthermore, a porous semiconductor layer formed from semiconductor fine particles is preferable from the viewpoint that the utilization factor of incident light and the like can be adjusted by the particle size of the semiconductor fine particles. Further, the semiconductor layer may be a single layer or a multilayer. By forming a multilayer, a sufficiently thick semiconductor layer can be more easily formed. Moreover, when the porous semiconductor layer formed from semiconductor fine particles is a multilayer, you may form several semiconductor layers from which the average particle diameter of semiconductor fine particles differs. For example, the average particle diameter of the semiconductor fine particles of the semiconductor layer closer to the light incident side (first semiconductor layer) may be smaller than that of the semiconductor layer farther from the light incident side (second semiconductor layer). In this way, the first semiconductor layer absorbs a lot of light, and the light that has passed through the first semiconductor layer is efficiently scattered by the second semiconductor layer and returned to the first semiconductor layer, and the returned light is returned to the first semiconductor layer. By making it absorb with 1 semiconductor layer, the whole optical absorptance can be improved further.

The film thickness of the semiconductor layer is not particularly limited, but can be set to, for example, not less than 0.5 μm and not more than 45 μm from the viewpoints of permeability and conversion efficiency. More preferably, they are 1 micrometer or more and 30 micrometers or less. The specific surface area of the semiconductor layer can be set to, for example, 10 m ² / g or more and 200 m ² / g or less from the viewpoint of adsorbing a large amount of dye.

  Further, in the case where the dye is adsorbed on the porous semiconductor layer, the porosity of the porous semiconductor layer is, for example, 40% or more from the viewpoint that ions in the electrolyte are further sufficiently diffused and charge transport is performed. 80% or less is preferable. Here, the porosity is a percentage of the volume of the semiconductor layer occupied by the pores in the semiconductor layer.

<Method for forming semiconductor layer>
Next, a method for forming the semiconductor layer 1 will be described by taking the case of a porous semiconductor layer as an example. The porous semiconductor layer can be formed, for example, as follows. First, a suspension is prepared by adding semiconductor fine particles together with an organic compound such as a resin and a dispersant to a dispersion medium such as an organic solvent or water. And this suspension is apply | coated on a conductive substrate (transparent conductive layer 2 in FIG. 1), a semiconductor layer is obtained by drying and baking this. When an organic compound is added to the dispersion medium together with the semiconductor fine particles, the organic compound is combusted at the time of firing, so that a sufficient gap (void) can be secured in the porous semiconductor layer. Moreover, the porosity can be changed by controlling the molecular weight and the addition amount of the organic compound combusted at the time of baking.

  The organic compound is not particularly limited as long as it can be dissolved in a suspension and burned and removed when fired. For example, polyethylene glycol, cellulose ester resin, cellulose ether resin, epoxy resin, urethane resin, phenol resin, polycarbonate resin, polyarylate resin, polyvinyl butyral resin, polyester resin, polyvinyl formal resin, silicone resin, styrene, Examples thereof include polymers and copolymers of vinyl compounds such as vinyl acetate, acrylic acid esters, and methacrylic acid esters. The type and amount of the organic compound can be appropriately selected according to the type and state of the fine particles used, the composition ratio of the suspension, the total weight, and the like. The ratio of the semiconductor fine particles is preferably 10% by mass or more and 40% by mass or less with respect to the total weight of the entire suspension. When the ratio of the semiconductor fine particles is 10% by mass or more based on the total weight of the entire suspension, the strength of the produced film can be further sufficiently increased. Moreover, if the ratio of the semiconductor fine particles is 40% by mass or less with respect to the total weight of the whole suspension, a porous semiconductor layer having a large porosity can be obtained more stably.

  As the semiconductor fine particles, single or plural compound semiconductor particles having an appropriate average particle diameter, for example, an average particle diameter of about 1 nm to 500 nm can be used. Among these, from the viewpoint of increasing the specific surface area, those having an average particle diameter of about 1 nm to 50 nm are desirable. In order to increase the utilization factor of incident light, semiconductor particles having a relatively large average particle diameter of about 200 nm to 400 nm may be added.

  Examples of the method for producing the semiconductor fine particles include a sol-gel method such as a hydrothermal synthesis method, a sulfuric acid method, and a chlorine method. The method is not limited as long as the method can produce the desired fine particles. Is preferably synthesized by a hydrothermal synthesis method.

  Examples of the dispersion medium used for the suspension include glyme solvents such as ethylene glycol monomethyl ether; alcohols such as isopropyl alcohol; mixed solvents such as isopropyl alcohol / toluene; water and the like.

  The suspension can be applied by a usual application method such as a doctor blade method, a squeegee method, a spin coating method, or a screen printing method. The conditions of drying and baking of the coating film performed after application of the suspension are, for example, about 10 seconds to 12 hours in the range of about 50 ° C. to 800 ° C. in the air or in an inert gas atmosphere. it can. This drying and baking may be performed once or a plurality of times at a single temperature, or may be performed a plurality of times by changing the temperature.

  Other types of semiconductor layers other than the porous semiconductor layer can be formed using a normal method for forming a semiconductor layer used in a photoelectric conversion element for a photoelectrochemical cell.

<Adsorption method of photoelectric conversion dye>
The photoelectric conversion dye is as described above. As a method for adsorbing the dye to the semiconductor layer 1, for example, a method in which a semiconductor substrate (that is, a conductive substrate having the semiconductor layer 1) is immersed in a solution in which the dye is dissolved, or a solution of the dye is used as a semiconductor layer. The method of apply | coating to 1 and making it adsorb | suck is mentioned.

  Solvents for this dye solution include nitrile solvents such as acetonitrile, propionitrile, methoxyacetonitrile; alcohol solvents such as methanol, ethanol, isopropyl alcohol; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone; acetic acid Ester solvents such as ethyl and butyl acetate; ether solvents such as tetrahydrofuran and dioxane; amide solvents such as N, N-dimethylformamide, N, N-dimethylacetamide and N-methyl-2-pyrrolidone; dichloromethane, chloroform, And halogen solvents such as dichloroethane, trichloroethane, and chlorobenzene; hydrocarbon solvents such as toluene, xylene, and cyclohexane; and water. These may be used alone or in combination of two or more.

  When the method of immersing the semiconductor substrate in the dye solution is employed, the solution may be stirred, heated to reflux, or ultrasonic waves may be applied when the semiconductor substrate is immersed in the dye solution. it can.

  After the dye adsorption treatment, it is desirable to wash with a solvent such as alcohol in order to remove the dye remaining without being adsorbed.

The amount of the dye supported can be set, for example, within a range of 1 × 10 ⁻¹⁰ mol / cm ^{2 to} 1 × 10 ⁻⁴ mol / cm ² , and is 1 × 10 ⁻⁹ mol / cm ^{2 to} 9.0 × 10. A range of ⁻⁶ mol / cm ² or less is preferred. Within this range, the effect of improving the photoelectric conversion efficiency can be obtained economically and sufficiently.

  Further, in order to make the wavelength range capable of photoelectric conversion as wide as possible and increase the conversion efficiency, two or more types of photoelectric conversion dyes may be used in combination, in which case the absorption wavelength range and intensity of the dye are taken into consideration. Thus, it is preferable to appropriately select the type and ratio of the pigment. In addition, an additive may be used in combination when adsorbing the dye in order to suppress a decrease in conversion efficiency due to the association between the dyes. Examples of such additives include steroidal compounds having a carboxy group (for example, deoxycholic acid, cholic acid, chenodeoxycholic acid, etc.).

<Counter electrode>
The counter electrode 8 in this example has a catalyst layer 6 on a substrate 7. In this photoelectric conversion element for a photoelectrochemical cell, holes generated from the dye adsorbed on the semiconductor layer 1 due to the incidence of light are carried to the counter electrode 8 through the electrolyte layer 5. There is no limit to the material as long as it can perform the function of effectively eliminating the pair.

  The catalyst layer 6 can be formed as a metal vapor deposition film on the substrate 7, for example, by vapor deposition or the like. The catalyst layer 6 may be, for example, a Pt layer formed on the substrate 7. Further, the catalyst layer 6 may contain a nanocarbon material. For example, the catalyst layer 6 may be formed by sintering a paste containing carbon nanotubes, carbon nanohorns, or carbon fibers on the porous insulating film. Nanocarbon materials have a large specific surface area and can improve the probability of annihilation of electrons and holes.

  Examples of the substrate 7 include a transparent substrate such as glass and a polymer film, and a metal plate (foil). In the case of producing the light-transmitting counter electrode 8, a glass with a transparent conductive film is selected as the substrate 7, and platinum, carbon, or the like is formed as the catalyst layer 6 using a vapor deposition method or a sputtering method. be able to.

<Electrolyte layer (charge transport layer)>
The electrolyte layer (charge transport layer) 5 has a function of transporting holes generated from the dye adsorbed on the semiconductor layer 1 due to incidence of light to the counter electrode 8. The electrolyte layer 5 contains a charge transport material. The electrolyte layer 5 includes an electrolytic solution in which a redox couple is dissolved in an organic solvent, a gel electrolyte in which a liquid in which the redox couple is dissolved in an organic solvent is impregnated in a polymer matrix, a molten salt containing the redox couple, a solid electrolyte, an organic A hole transport material or the like can be used.

The electrolyte layer can be composed of an electrolyte, a solvent, and an additive. As the electrolyte, LiI, NaI, KI, CsI , CaI 2 , etc. of the metal iodides, tetraalkylammonium iodide, pyridinium iodide, imidazolium iodide iodide and _{I 2,} such as iodine salts of quaternary ammonium compounds such as id A combination of a bromide such as a bromide of a quaternary ammonium compound such as a metal bromide such as LiBr, NaBr, KBr, CsBr or CaBr ₂ or a tetraalkylammonium bromide or pyridinium bromide; and a Br ₂ salt; Metal complexes such as ferricyanate and ferrocene-ferricinium ions; sulfur compounds such as sodium polysulfide and alkylthiol-alkyl disulfides; viologen dyes; hydroquinone-quinone and the like. Among these, a combination of LiI and pyridinium iodide, or a combination of imidazolium iodide and I ₂ is preferable. Moreover, said electrolyte may be used independently or may be used in mixture of 2 or more types. In addition, a molten salt that is in a molten state at room temperature can be used as the electrolyte. In this case, a solvent need not be used.

  Examples of the solvent include carbonate solvents such as ethylene carbonate, diethyl carbonate, dimethyl carbonate, and propylene carbonate; amide solvents such as N-methyl-2-pyrrolidone and N, N-dimethylformamide; methoxypropionitrile, pro Nitrile solvents such as pionitrile, methoxyacetonitrile, acetonitrile; lactone solvents such as γ-butyrolactone and valerolactone; ether solvents such as tetrahydrofuran, dioxane, diethyl ether, ethylene glycol dialkyl ether; methanol, ethanol, isopropyl alcohol, etc. Alcohol solvents; aprotic polar solvents such as dimethyl sulfoxide, sulfolane; 2-methyl-3-oxazolidinone, 2-methyl-1,3-dioxola Heterocyclic compounds, and the like and the like. These solvents may be used alone or in combination of two or more.

  A basic compound may be added to the electrolyte layer in order to suppress dark current. Although it does not specifically limit as a kind of basic compound, t-butyl pyridine, 2-picoline, 2, 6- lutidine, etc. are mentioned. The addition concentration in the case of adding a basic compound can be, for example, about 0.05 mol / L or more and 2 mol / L or less.

  A solid electrolyte can also be used as the electrolyte layer. As this solid electrolyte, a gel electrolyte or a completely solid electrolyte can be used. As gel electrolyte, what added electrolyte or normal temperature molten salt in the gelatinizer can be used. As a gelation method, gelation can be performed by a technique such as addition of a polymer or an oil gelling agent, polymerization of coexisting polyfunctional monomers, or a polymer crosslinking reaction. Examples of the polymer for gelation by adding a polymer include polyacrylonitrile and polyvinylidene fluoride. Oil gelling agents include dibenzylden-D-sorbitol, cholesterol derivatives, amino acid derivatives, alkylamide derivatives of trans- (1R, 2R) -1,2-cyclohexanediamine, alkylurea derivatives, N-octyl-D-gluconamide benzoate Double-headed amino acid derivatives, quaternary ammonium salt derivatives, and the like.

  When gelation is performed by polymerization of a polyfunctional monomer, the monomer used is preferably a compound having two or more ethylenically unsaturated groups, such as divinylbenzene, ethylene glycol dimethacrylate, ethylene glycol diacrylate, Examples include diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, triethylene glycol diacrylate, pentaerythritol triacrylate, and trimethylolpropane triacrylate. In the gelation, a monofunctional monomer may be included in addition to the polyfunctional monomer. Monofunctional monomers include esters derived from acrylic acid and α-alkyl acrylic acids such as acrylamide, N-isopropylacrylamide, methyl acrylate and hydroxyethyl acrylate; amides; dimethyl maleate, diethyl fumarate, dibutyl maleate Esters derived from maleic acid and fumaric acid such as: Dienes such as butadiene, isoprene and cyclopentadiene; Aromatic vinyl compounds such as styrene, p-chlorostyrene and sodium styrenesulfonate; Vinyl esters such as vinyl acetate Nitriles such as acrylonitrile and methacrylonitrile; vinyl compounds having a nitrogen-containing heterocycle such as vinyl carbazole; vinyl compounds having a quaternary ammonium salt; other N-vinylformamide and vinyl sulfone , Vinylidene fluoride, vinyl alkyl ethers, N- phenylmaleimide, and the like. 0.5 mass% or more and 70 mass% or less are preferable, and, as for the polyfunctional monomer which occupies for the monomer whole quantity, 1.0 mass% or more and 50 mass% or less are more preferable.

  Polymerization of the monomer for gelation can be performed by a radical polymerization method or the like. This radical polymerization can be carried out by heating, light, ultraviolet light or electron beam, or electrochemically. Examples of the polymerization initiator used when forming a crosslinked polymer by heating include azo initiators such as 2,2′-azobis (isobutyronitrile) and 2,2′-azobis (dimethylvaleronitrile), Examples thereof include peroxide initiators such as benzoyl peroxide. The addition amount of the polymerization initiator is preferably 0.01% by mass or more and 15% by mass or less, and more preferably 0.05% by mass or more and 10% by mass or less with respect to the total amount of monomers.

  When gelation is performed by a crosslinking reaction of a polymer, it is desirable to use a polymer having a reactive group necessary for the crosslinking reaction and a crosslinking agent in combination. Preferred crosslinkable reactive groups are nitrogen-containing heterocycles such as pyridine ring, imidazole ring, thiazole ring, oxazole ring, triazole ring, morpholine ring, piperidine ring, piperazine ring, and preferred crosslinkers are alkyl halides, halogenated alkyls. Bifunctional or higher functional compounds capable of electrophilic substitution reaction with nitrogen atoms such as aralkyl, sulfonic acid ester, acid anhydride, acid chloride, isocyanate and the like can be mentioned.

  As the complete solid electrolyte, for example, a mixture of an electrolyte and an ion conductive polymer compound can be used. Examples of the ion conductive polymer compound include polar polymer compounds such as polyethers, polyesters, polyamines, and polysulfides.

  As the charge transport material, for example, an inorganic hole transport material such as copper iodide or copper thiocyanide can be used. The inorganic hole transport material can be introduced into the electrode by a method such as a casting method, a coating method, a spin coating method, a dipping method, or electrolytic plating.

  In the photoelectric conversion element for a photoelectrochemical cell of this example, an organic hole transport material can also be used as the charge transport material. Examples of the organic hole transport material include 2,2 ′, 7,7′-tetrakis (N, N-di-p-methoxyphenylamine) -9,9′-spirobifluorene (for example, Adv. Mater. 2005). , 17, 813), and aromatic diamines such as N, N′-diphenyl-N, N′-bis (3-methylphenyl)-(1,1′-biphenyl) -4,4′-diamine (For example, compounds described in US Pat. No. 4,764,625), triphenylamine derivatives (for example, compounds described in JP-A-4-129271), and stilbene derivatives (for example, JP-A-2-511262). Compounds), hydrazone derivatives (for example, compounds described in JP-A-2-226160) and the like. The organic hole transport material can be introduced into the electrode by a method such as a vacuum deposition method, a cast method, a spin coating method, a dipping method, or an electrolytic polymerization method.

  The electrolyte layer 5 can be produced, for example, by the following two methods. One is a method in which the counter electrode 8 is first bonded onto the semiconductor layer 1 on which the photoelectric conversion dye is adsorbed, and the liquid electrolyte layer 5 is introduced into the gap. The other is a method of forming the electrolyte layer 5 directly on the semiconductor layer 1. In the latter case, the counter electrode 8 is formed on the electrolyte layer 5 after it is formed.

  A photoelectrochemical cell can be provided by using the photoelectric conversion element for a photoelectrochemical cell described above. This photoelectrochemical cell can be suitably used as a solar cell.

  Hereinafter, the present invention will be described more specifically with reference to examples.

Example 1
<Synthesis of Alkyne Derivative TA-1>
According to the following reaction formula, the alkyne derivative TA-1 was synthesized as follows.

  30 g of 4-iodo-4 ′, 4 ″ -dimethoxytriphenylamine is dissolved in 630 mL of diethylamine, to which 317 mg of copper iodide (CuI) and 2.22 g of bis (triphenylphosphine) palladium (II) dichloride are added, Further, 11.4 mL of trimethylsilylacetylene was added and stirred at 60 ° C. for 1.5 hours. After returning to room temperature, the solvent was distilled off under reduced pressure, 100 mL of water was added to the residue, extracted with diethyl ether, washed with 100 mL of water, and the organic layer was dried over magnesium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified by a silica gel column (eluent: hexane / chloroform = 3/1) to obtain 31 g of Compound A1.

  Next, 15.5 g of A1 was dissolved in 100 mL of methanol, and 6.92 g of potassium carbonate was added thereto, followed by stirring at room temperature for 1 hour. Celite filtration was performed, the solvent was distilled off under reduced pressure, and the residue was purified by a silica gel column (eluent: hexane / chloroform = 3/1) to obtain 7.7 g of A2.

  Next, to a mixed solution of 1 g of A2, 0.912 g of 5-bromo-5′-formyl-2,2′-bithiophene and 60 mL of diisopropylamine, 95.4 mg of triphenylphosphine and bis (triphenylphosphine) palladium (II ) 128 mg of dichloride was added and heated to reflux for 1 hour. The temperature was returned to room temperature, the solvent was distilled off under reduced pressure, water was added to the residue, and the mixture was extracted with chloroform. The organic layer was washed with water and dried over magnesium sulfate, and the solvent was distilled off under reduced pressure. The residue was purified by a silica gel column (eluent: hexane / toluene = 2/8) to obtain 0.285 g of Compound A3 (yield 12%).

  Next, 1 g of A3 is dissolved in 50 mL of chloroform, 0.245 g of cyanoacetic acid and 0.41 g of piperidine are added thereto, and the mixture is heated to reflux for 9.5 hours. After allowing to cool, 200 mL of chloroform was added, washed with 0.04N hydrochloric acid and further washed with water, and then the organic layer was dried over magnesium sulfate. The solvent was distilled off under reduced pressure, the residue was dissolved in tetrahydrofuran (THF), and reprecipitated in 360 mL of hexane / ethyl acetate (5/1) to obtain 0.297 g of the desired alkyne derivative TA-1. Yield 26%).

The measurement results of ¹ H-NMR (THF-d8) of the obtained alkyne derivative TA-1 were as follows: δ was 8.44 (1H, s), 8.01 (1H, s), 7 .95 (1H, d), 7.53-7.55 (2H, m), 7.33 (2H, d), 7.29 (1H, d), 7.12 (4H, d), 6. 95 (4H, d), 6.77 (2H, d)

Moreover, the absorption spectrum curve in THF of the obtained alkyne derivative TA-1 (dye) is shown in FIG. Λ _max of the alkyne derivative TA-1 was 462 nm.

(Example 2)
<Synthesis of Alkyne Derivative TA-2>
According to the following reaction formula, the alkyne derivative TA-2 was synthesized as follows.

  A solution obtained by dissolving 21.1 g of N-bromosuccinimide (NBS) in 280 mL of DMF in a solution of 39.5 g of 3,4′-dihexyl-2,2′-bithiophene in N, N-dimethylformamide (DMF) at 0 ° C. Was dripped. After stirring for 1 hour, the mixture was extracted with diethyl ether at 500 mL, and the organic layer was washed with water, saturated aqueous sodium carbonate solution and brine in that order, and dried over magnesium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified with a silica gel column (elution solvent: hexane) to obtain 49.3 g of B1.

  Next, 585 mL of 2M aqueous sodium carbonate solution and tetrakis (triphenylphosphine) palladium (0) were added to a toluene solution of 49.3 g of B1 and 4-hexylthiophene-2-boranoic acid pinacol ester 38.2 g, and heated for 48 hours. Refluxed. It returned to room temperature, the organic layer was wash | cleaned in order of water and salt solution, and it dried with magnesium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified with a silica gel column (elution solvent: hexane) to obtain 58.3 g of B2.

  Next, 77.7 mL of n-butyllithium (1.64 M hexane solution) was added dropwise to 58.3 g of a solution of B2 in 700 mL of THF at −78 ° C., and the mixture was stirred for 2 hours. At the same temperature, 13.5 mL of DMF was added and stirred for 1 hour. The mixture was returned to room temperature and further stirred for 1 hour. Water was added and extracted with diethyl ether. The organic layer was washed with brine and dried over magnesium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified with a silica gel column (elution solvent: hexane / ethyl acetate = 20/1) to obtain 39.84 g of B3.

  Next, 39.84 g of B3 was dissolved in 480 mL of DMF, and 13.41 g of NBS was added thereto at −20 ° C., followed by stirring for 1 hour. It returned to room temperature and stirred for 2 hours. The mixture was extracted with diethyl ether, washed successively with water, a saturated aqueous sodium carbonate solution and brine, and the organic layer was dried over magnesium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified with a silica gel column (elution solvent: hexane / ethyl acetate = 20/1) to obtain 44.59 g of B4.

  Next, 19.5 g of A2 synthesized in Example 1 and 30 g of B4 were dissolved in 1150 mL of diisopropylamine, and 1.55 g of triphenylphosphine and 2.08 g of bis (triphenylphosphine) palladium (II) dichloride were added thereto. Then, 564 mg of copper iodide (CuI) was added, stirred at room temperature for 1 hour, and then stirred at 50 ° C. for 30 minutes. Then, it heated and refluxed for 30 minutes. The temperature was returned to room temperature, and the solvent was distilled off under reduced pressure. The residue was purified by a silica gel column (elution solvent: hexane / ethyl acetate = 20/1) to obtain 35.3 g of B5.

  Next, 2 g of B5, 0.298 g of cyanoacetic acid, and 0.497 g of piperidine were dissolved in 60 mL of chloroform and heated to reflux for 9 hours. The temperature was returned to room temperature, the solvent was distilled off under reduced pressure, 200 mL of chloroform was added, washed with 0.04N hydrochloric acid, further washed with water, and then the organic layer was dried over magnesium sulfate. The solvent was distilled off under reduced pressure, and the residue was dissolved in a small amount of THF and reprecipitated in 400 mL of hexane to obtain 1.251 g of the target TA-2 (yield 57%).

The measurement results of ¹ H-NMR (THF-d8) of the obtained alkyne derivative TA-2 were as follows: δ was 8.22 (1H, s), 7.68 (1H, s), 7 .24-7.27 (3H, m), 7.05-7.08 (5H, m), 6.87 (4H, d), 6.81 (2H, d), 3.76 (6H, s) ), 2.7-2.9 (6H, m), 1.3-1.9 (24H, m), 0.89-0.93 (9H, m)

Moreover, the absorption spectrum curve in THF of obtained alkyne derivative TA-2 (dye) is shown in FIG. Λ _max of the alkyne derivative TA-2 was 453 nm.

(Example 3)
<Production of photoelectric conversion element for photoelectrochemical cell>
A photoelectric conversion element for a photoelectrochemical cell was produced as follows.
(A) Production of Photoelectrochemical Battery Semiconductor Electrode and Counter Electrode First, a photoelectrochemical battery semiconductor electrode was produced in the following order.
A glass with FTO (10 Ωcm ² ) having a size of 15 mm × 15 mm and a thickness of 1.1 mm was prepared as a conductive substrate (light transmissive substrate with a transparent conductive layer).

  A titanium oxide paste (semiconductor layer material) was prepared as follows. Commercially available titanium oxide powder (trade name: P25, manufactured by Nippon Aerosil Co., Ltd., average primary particle size: 21 nm) 5 g, 15 vol% acetic acid aqueous solution 20 mL, surfactant 0.1 mL (trade name: Triton (registered trademark) X- 100, manufactured by Sigma-Aldrich Co., Ltd.) and 0.3 g of polyethylene glycol (molecular weight 20000) (manufactured by Wako Pure Chemical Industries, Ltd., product code: 168-11285) were mixed, and this mixture was stirred for about 1 hour with a stirring mixer, and oxidized. A titanium paste was obtained.

  Next, this titanium oxide paste was applied on a glass with FTO by a doctor blade method so that the film thickness was about 50 μm (application area: 10 mm × 10 mm). Thereafter, the glass with FTO coated with the titanium oxide paste was put in an electric furnace, baked at 450 ° C. for about 30 minutes in an air atmosphere, and naturally cooled to obtain a porous titanium oxide film on the glass with FTO. .

  Further, a light scattering layer was formed on the titanium oxide film as follows. A titanium oxide paste having an average particle diameter of 400 nm (trade name: PST-400C, manufactured by JGC Catalysts & Chemicals Co., Ltd.) was applied to the above-described titanium oxide film with a thickness of 20 μm by a screen printing method. Then, the light-scattering layer on the titanium oxide film was obtained by baking for about 30 minutes at 450 degreeC in air | atmosphere, and allowing it to cool naturally. As described above, a semiconductor electrode before the dye was adsorbed was obtained.

  On the other hand, a platinum layer having an average film thickness of 1 μm was deposited as a catalyst layer on a soda lime glass plate (thickness 1.1 mm) by a vacuum deposition method to obtain a counter electrode.

(B) Adsorption of dye Next, the dye for photoelectric conversion was adsorbed on the semiconductor layer composed of the titanium oxide film and the light scattering layer. For adsorption of the photoelectric conversion dye, a solution in which the alkyne derivative TA-1 of Example 1 was dissolved in THF at a concentration of about 2 × 10 ⁻⁴ M was used. The above-mentioned semiconductor electrode was immersed in this dye solution and stored overnight. Thereafter, the semiconductor electrode was taken out from the dye solution, rinsed with acetonitrile to remove excess dye, and dried in air to obtain a semiconductor electrode on which the photoelectric conversion dye was adsorbed.

(C) Cell assembly The semiconductor electrode for photoelectrochemical cell after the above-mentioned dye conversion treatment for photoelectric conversion and the above-mentioned counter electrode are arranged so that the semiconductor layer and the catalyst layer face each other to form a cell before electrolyte injection did. Next, a thermosetting resin film in which the electrolyte was allowed to penetrate into the gap between the semiconductor electrode and the counter electrode was thermocompression bonded to the outer periphery of the cell.

(D) Injection of electrolyte An iodine-based electrolyte was injected into the above-described cell from the above-mentioned cut and allowed to penetrate between the semiconductor electrode and the counter electrode. The iodine-based electrolyte uses acetonitrile as a solvent, the iodine concentration is 0.5 mol / L, the lithium iodide concentration is 0.1 mol / L, the 4-tert-butylpyridine concentration is 0.05 mol / L, 1, A solution having a concentration of 2-dimethyl-3-propylimidazolium iodide of 0.6 mol / L was used.

(E) Photocurrent measurement The photoelectric conversion element for a photoelectrochemical cell produced as described above is irradiated with light having an intensity of 100 mW / cm ² under AM1.5 conditions with a solar simulator, and the generated electricity is converted into a current. It measured with the voltage measuring device and evaluated the photoelectric conversion characteristic. As a result, the photoelectric conversion efficiency was 3.3%.

(Example 4)
A photoelectric conversion element was produced in the same manner as in Example 3 except that the alkyne derivative TA-2 was used instead of the alkyne derivative TA-1. As a result of evaluating the photoelectric conversion characteristics of the obtained photoelectric conversion element, a 3.5% photoelectric conversion efficiency was obtained in the element using TA-2.

  As described above, the alkyne derivative of the present invention, its tautomer or stereoisomer, or a salt thereof is useful as a photoelectric conversion dye. The photoelectric conversion dye containing the alkyne derivative of the present invention is excellent in photoelectric conversion characteristics. Further, since no precious metal such as ruthenium is essential, the problem of resource limitation is solved, and solar cells can be supplied at a lower cost. Therefore, the solar cell can be used for a wide range of applications. The use of the alkyne derivative of the present invention is not limited to this, and can be used in various fields.

  A part or all of the above-described embodiment can be described as in the following supplementary notes, but is not limited thereto.

前記式（１）中、
Ｄは、電子供与性置換基を含む有機基を表し、
Ｘは、酸性基を有する基を表し、
Ｚは、チオフェン環、フラン環およびピロール環からなる群から選択される少なくとも一種の複素環を有する連結基を表す。 (Appendix 1)
An alkyne derivative represented by the following general formula (1), a tautomer or stereoisomer thereof, or a salt thereof.

In the formula (1),
D represents an organic group containing an electron-donating substituent,
X represents a group having an acidic group,
Z represents a linking group having at least one heterocyclic ring selected from the group consisting of a thiophene ring, a furan ring and a pyrrole ring.

前記式（５）中、Ａｒ^１およびＡｒ^２は、それぞれ独立に置換若しくは無置換のアルキル基、置換若しくは無置換のアリール基または複素環基を表す。Ａｒ^３は置換若しくは無置換のアリーレン基、または置換もしくは無置換の二価の複素環基を表す。 (Appendix 2)
The alkyne derivative according to appendix 1, wherein the organic group D containing the electron donating substituent is a group represented by the following general formula (5), a tautomer or stereoisomer thereof, salt.

In the formula (5), Ar ¹ and Ar ² each independently represent a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group or a heterocyclic group. Ar ³ represents a substituted or unsubstituted arylene group or a substituted or unsubstituted divalent heterocyclic group.

前記式（Ｄ３）〜（Ｄ６）、（Ｄ９）中のＲは、炭素数１〜８のアルキル基を表す。 (Appendix 3)
The alkyne derivative according to appendix 1, wherein the organic group D containing the electron-donating substituent is a group represented by any of the following formulas (D1) to (D9), a tautomer thereof, or Stereoisomers or their salts.

R in the formulas (D3) to (D6) and (D9) represents an alkyl group having 1 to 8 carbon atoms.

(Appendix 4)
The alkyne derivative according to any one of appendices 1 to 3, wherein X is an organic group having an acidic group, a tautomer or stereoisomer thereof, or a salt thereof.

(Appendix 5)
6. The alkyne derivative according to appendix 4, a tautomer or stereoisomer thereof, or a salt thereof, wherein X is a group in which an acidic group is bonded to a group that can be conjugated with Z.

(Appendix 6)
6. The alkyne derivative according to appendix 5, a tautomer or stereoisomer thereof, or a salt thereof, wherein the group capable of conjugating with Z is a group having a carbon-carbon double bond.

前記式（Ｘａ）〜（Ｘｍ）中、
Ｍは、水素原子または塩形成性陽イオンを表し、
Ｂ⁻は、水酸化物イオンまたは塩形成性陰イオンを表す。 (Appendix 7)
The alkyne derivative according to any one of appendices 1 to 6, wherein X is a group represented by any one of the following formulas (Xa) to (Xm), a tautomer or stereoisomer thereof, Or their salts.

In the formulas (Xa) to (Xm),
M represents a hydrogen atom or a salt-forming cation,
B ⁻ represents a hydroxide ion or a salt-forming anion.

(Appendix 8)
X is a group represented by any one of the following formulas (X1) to (X16), the alkyne derivative according to any one of appendices 1 to 6, a tautomer or stereoisomer thereof, Or their salts.

前記式（２）中、Ｍは、水素原子または塩形成性陽イオンを表す。 (Appendix 9)
X is a group represented by the following general formula (2), the alkyne derivative according to any one of supplementary notes 1 to 6, a tautomer or stereoisomer thereof, or a salt thereof.

In the formula (2), M represents a hydrogen atom or a salt-forming cation.

前記式（３）中、Ｒ^１、Ｒ^２は、それぞれ独立に水素原子、置換若しくは無置換の直鎖若しくは分枝アルキル基、または置換若しくは無置換の直鎖若しくは分枝アルコキシ基を表し、Ｒ^１、Ｒ^２は互いに連結されて環を形成してもよく、
Ｙは、酸素原子、硫黄原子またはＮＲａを表し、
Ｒａは、水素原子、置換若しくは無置換の直鎖若しくは分枝アルキル基、または置換若しくは無置換の直鎖若しくは分枝アリール基を表す。 (Appendix 10)
Z is an atomic group including a structure represented by the following general formula (3), the alkyne derivative according to any one of appendices 1 to 9, a tautomer or stereoisomer thereof, or those Salt.

In the formula (3), R ¹ and R ² each independently represents a hydrogen atom, a substituted or unsubstituted linear or branched alkyl group, or a substituted or unsubstituted linear or branched alkoxy group, and R ¹ and R ² may be connected to each other to form a ring;
Y represents an oxygen atom, a sulfur atom or NRa;
Ra represents a hydrogen atom, a substituted or unsubstituted linear or branched alkyl group, or a substituted or unsubstituted linear or branched aryl group.

前記式（４）中、
Ａｒ^１およびＡｒ^２は、それぞれ独立に置換若しくは無置換のアルキル基、置換若しくは無置換のアリール基、または、置換若しくは無置換の複素環基を表し、
Ａｒ^３は置換若しくは無置換のアリーレン基、または置換もしくは無置換の二価の複素環基を表し、
Ｍは、水素原子または塩形成性陽イオンを表し、
Ｚは、下記一般式（３）で表される構造を含む連結基を表す。

前記式（３）中、
Ｒ^１、Ｒ^２は、それぞれ独立に水素原子、置換若しくは無置換の直鎖若しくは分枝アルキル基、または置換若しくは無置換の直鎖若しくは分枝アルコキシ基を表し、Ｒ^１、Ｒ^２は互いに連結されて環を形成してもよく、
Ｙは、酸素原子、硫黄原子、またはＮＲａを表し、
Ｒａは、水素原子、置換若しくは無置換の直鎖若しくは分枝アルキル基、または置換若しくは無置換のアリール基を表す。 (Appendix 11)
The alkyne derivative according to any one of appendices 1 to 10, which is represented by the following general formula (4), a tautomer or stereoisomer thereof, or a salt thereof.

In the formula (4),
Ar ¹ and Ar ² each independently represent a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group;
Ar ³ represents a substituted or unsubstituted arylene group, or a substituted or unsubstituted divalent heterocyclic group,
M represents a hydrogen atom or a salt-forming cation,
Z represents a linking group including a structure represented by the following general formula (3).

In the formula (3),
R ¹ and R ² each independently represents a hydrogen atom, a substituted or unsubstituted linear or branched alkyl group, or a substituted or unsubstituted linear or branched alkoxy group, and R ¹ and R ² are connected to each other. To form a ring,
Y represents an oxygen atom, a sulfur atom, or NRa;
Ra represents a hydrogen atom, a substituted or unsubstituted linear or branched alkyl group, or a substituted or unsubstituted aryl group.

(Appendix 12)
R ¹ and R ² , wherein the alkyl group has 1 to 12 carbon atoms and the aryl group has 5 to 24 carbon atoms, the alkyne derivative according to appendix 11, a tautomer thereof, or Stereoisomers or their salts.

(Appendix 13)
Z is represented by any one of the following formulas (Z1) to (Z24), the alkyne derivative according to any one of appendices 1 to 12, its tautomer or stereoisomer, or their salt.

(Appendix 14)
The alkyne derivative according to Supplementary Note 1, represented by the following formula TA-1, a tautomer or stereoisomer thereof, or a salt thereof.

(Appendix 15)
The alkyne derivative according to Supplementary Note 1, represented by the following formula TA-2, a tautomer or stereoisomer thereof, or a salt thereof.

(Appendix 16)
A dye for photoelectric conversion, comprising at least one of the alkyne derivative according to any one of appendices 1 to 15, a tautomer or stereoisomer thereof, or a salt thereof.

(Appendix 17)
A semiconductor electrode for a photoelectrochemical cell, comprising a semiconductor layer containing the photoelectric conversion dye according to appendix 16.

(Appendix 18)
The semiconductor electrode for a photoelectrochemical cell according to appendix 17, wherein the semiconductor layer is at least one selected from the group consisting of a single semiconductor, a compound semiconductor, a metal chalcogenide, and a compound having a perovskite structure.

(Appendix 19)
The semiconductor electrode for a photoelectrochemical cell according to appendix 18, wherein the single semiconductor is at least one of silicon and germanium.

(Appendix 20)
The metal chalcogenide is an oxide of titanium, tin, zinc, iron, tungsten, indium, zirconium, vanadium, niobium, tantalum, strontium, hafnium, cerium, or lanthanum; cadmium, zinc, lead, silver, antimony, or bismuth The semiconductor electrode for a photoelectrochemical cell according to appendix 18 or 19, wherein the semiconductor electrode is at least one selected from the group consisting of sulfides; selenides of cadmium and lead; and tellurides of cadmium.

(Appendix 21)
21. The metal chalcogenide according to appendix 20, wherein at least one selected from the group consisting of zinc, gallium, indium, or cadmium phosphide; gallium arsenide; copper-indium-selenide; and copper-indium-sulfide The semiconductor electrode for photoelectrochemical cells according to any one of appendices 18 to 20, wherein

(Appendix 22)
The photoelectrochemistry according to any one of appendices 18 to 21, wherein the compound having a perovskite structure is at least one selected from the group consisting of barium titanate, strontium titanate, and potassium niobate. Semiconductor electrode for batteries.

(Appendix 23)
23. The semiconductor electrode for a photoelectrochemical cell according to any one of appendices 17 to 22, wherein the semiconductor layer contains titanium oxide or zinc oxide.

(Appendix 24)
A photoelectric conversion element for a photoelectrochemical cell, comprising the semiconductor electrode for a photoelectrochemical cell according to any one of appendices 17 to 23.

(Appendix 25)
Furthermore, it has a counter electrode facing the semiconductor electrode for photoelectrochemical cells,
The photoelectric conversion element for a photoelectrochemical cell according to appendix 24, wherein a charge transport material is included between the semiconductor electrode for the photoelectrochemical cell and the counter electrode.

(Appendix 26)
A photoelectrochemical cell comprising the photoelectric conversion element for a photoelectrochemical cell according to appendix 24 or 25.

前記一般式（Ｉ）、（III）、（IV）および（VI）中、
Ｄは、前記一般式（１）と同じであり、
前記一般式（II）および（III）中、
Ｑ^１は、保護基であり、
前記一般式（Ｉ）中、
Ｈａｌ^１は、ハロゲンであり、
前記一般式（Ｖ）中、
Ｈａｌ^２は、ハロゲンであり、
Ｈａｌ^１とＨａｌ^２は同一でも異なっていてもよく、
前記一般式（Ｖ）および（VI）中、
Ｚは、前記一般式（１）と同じであり、
Ｑ^２は、酸性基Ｘに変換可能な任意の置換基である。 (Appendix 27)
The 1st coupling process which manufactures the compound represented by the following general formula (III) by the coupling reaction of the compound represented by the following general formula (I), and the compound represented by the following general formula (II) ,
A deprotection step for producing a compound represented by the following general formula (IV) by deprotecting the compound represented by the following general formula (III);
A second coupling step in which a compound represented by the following general formula (IV) and a compound represented by the following general formula (V) are subjected to a coupling reaction to produce a compound represented by the following general formula (VI); and,
Supplementary notes 1 to 15 including an acidic group introduction step of converting the Q ² in the following general formula (VI) to introduce an acidic group X to produce the compound represented by the general formula (1) Or a tautomer or stereoisomer thereof, or a salt thereof.

In the general formulas (I), (III), (IV) and (VI),
D is the same as the general formula (1),
In the general formulas (II) and (III),
Q ¹ is a protecting group,
In the general formula (I),
Hal ¹ is halogen,
In the general formula (V),
Hal ² is halogen,
Hal ¹ and Hal ² may be the same or different,
In the general formulas (V) and (VI),
Z is the same as the general formula (1),
Q ² is an arbitrary substituent that can be converted to the acidic group X.

(Appendix 28)
The production method according to appendix 27, wherein at least one of the first coupling step and the second coupling step is performed in the presence of a palladium catalyst and a base.

(Appendix 29)
The production method according to appendix 27, wherein at least one of the first coupling step and the second coupling step is performed in the presence of a palladium catalyst, a copper catalyst, and a base.

前記一般式（VII）および（VIII）中、
Ｒ^１０は、水素原子、置換若しくは無置換のアルキル基、または置換若しくは無置換のアリール基であり、
前記一般式（VIII）中、
−ＣＯＯＨのＨは、例えば、前記一般式（２）と同じＭで置換してもよい。 (Appendix 30)
In the general formulas (V) and (VI),
Q ² is an acyl group represented by the following general formula (VII),
In the general formula (I),
X is an acidic group represented by the following general formula (VIII),
In the acid group-introducing step, the manufacturing method according to any one of Appendixes 27 29 and converting by reacting cyanoacetic acid to Q ² in X.

In the general formulas (VII) and (VIII),
R ¹⁰ is a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group,
In the general formula (VIII),
For example, H in —COOH may be substituted with the same M as in the general formula (2).

DESCRIPTION OF SYMBOLS 1 Semiconductor layer 2 Transparent conductive layer 3 Light transmissive substrate 4 Semiconductor electrode for photoelectrochemical cells 5 Electrolyte layer (charge transport layer)
6 Catalyst layer 7 Substrate 8 Counter electrode

Claims (10)

An alkyne derivative represented by the following general formula (1), a tautomer or stereoisomer thereof, or a salt thereof.

In the formula (1),
D represents an organic group containing an electron-donating substituent,
X represents a group having an acidic group,
Z represents a linking group having at least one heterocyclic ring selected from the group consisting of a thiophene ring, a furan ring and a pyrrole ring. X is a group represented by any of the following formulas (Xa) to (Xm), the alkyne derivative, its tautomer or stereoisomer, or a salt thereof according to claim 1.

In the formulas (Xa) to (Xm),
M represents a hydrogen atom or a salt-forming cation,
B ⁻ represents a hydroxide ion or a salt-forming anion. The alkyne derivative, its tautomer or stereoisomer, or a salt thereof according to claim 1 or 2, wherein Z is an atomic group including a structure represented by the following general formula (3).

In the formula (3), R ¹ and R ² each independently represents a hydrogen atom, a substituted or unsubstituted linear or branched alkyl group, or a substituted or unsubstituted linear or branched alkoxy group, and R ¹ and R ² may be connected to each other to form a ring;
Y represents an oxygen atom, a sulfur atom or NRa;
Ra represents a hydrogen atom, a substituted or unsubstituted linear or branched alkyl group, or a substituted or unsubstituted linear or branched aryl group. The alkyne derivative, the tautomer or stereoisomer thereof, or a salt thereof according to any one of claims 1 to 3, which is represented by the following general formula (4).

In the formula (4),
Ar ¹ and Ar ² each independently represent a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group;
Ar ³ represents a substituted or unsubstituted arylene group, or a substituted or unsubstituted divalent heterocyclic group,
M represents a hydrogen atom or a salt-forming cation,
Z represents a linking group including a structure represented by the following general formula (3).

In the formula (3),
R ¹ and R ² each independently represents a hydrogen atom, a substituted or unsubstituted linear or branched alkyl group, or a substituted or unsubstituted linear or branched alkoxy group, and R ¹ and R ² are connected to each other. To form a ring,
Y represents an oxygen atom, a sulfur atom, or NRa;
Ra represents a hydrogen atom, a substituted or unsubstituted linear or branched alkyl group, or a substituted or unsubstituted aryl group.   A dye for photoelectric conversion comprising the alkyne derivative according to any one of claims 1 to 4, a tautomer or stereoisomer thereof, or a salt thereof.   A semiconductor electrode for a photoelectrochemical cell, comprising a semiconductor layer containing the photoelectric conversion dye according to claim 5.   The semiconductor electrode for photoelectrochemical cells according to claim 6, wherein the semiconductor layer contains titanium oxide or zinc oxide.   A photoelectric conversion element for a photoelectrochemical cell, comprising the semiconductor electrode for a photoelectrochemical cell according to claim 6 or 7. Furthermore, it has a counter electrode facing the semiconductor electrode for photoelectrochemical cells,
The photoelectric conversion element for a photoelectrochemical cell according to claim 8, further comprising a charge transport material between the semiconductor electrode for the photoelectrochemical cell and the counter electrode.   A photoelectrochemical cell comprising the photoelectric conversion element for a photoelectrochemical cell according to claim 8 or 9.

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