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Title:
ORGANIC DYE, DYE-SENSITIZED METAL OXIDE SEMICONDUCTOR ELECTRODE AND DYE-SENSITIZED SOLAR CELL
Document Type and Number:
WIPO Patent Application WO/2013/008951
Kind Code:
A1
Abstract:
An object of the present invention is to provide a dye sensitizer for a solar cell having stability and an excellent conversion efficiency. There is provided a dye sensitizer represented by the following general formula, to which a donor site (D) and an acceptor site (A) are bound via linkers (L1)n and (L2)n: (φ is an aromatic ring with or without heteroatom(s); D is a triphenylamine derivative, a carbazole derivative, a coumarine derivative or an indoline derivative; A is an organic residue having an acidic group; each of L1 and L2 is an optionally substituted divalent alkenyl group, aromatic group or heterocyclic group, and n represents an integer of 0 to 3).

Inventors:
ASHRAFUL ISLAM (JP)
HAN LIYUAN (JP)
Application Number:
PCT/JP2012/068404
Publication Date:
January 17, 2013
Filing Date:
July 12, 2012
Export Citation:
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Assignee:
NAT INST FOR MATERIALS SCIENCE (JP)
SAINT GOBAIN (FR)
ASHRAFUL ISLAM (JP)
HATA KAWAE (JP)
HAN LIYUAN (JP)
International Classes:
C09B57/00; H01G9/20; H01L51/30
Domestic Patent References:
WO2004063283A12004-07-29
Foreign References:
JP2009048925A2009-03-05
JP2004095450A2004-03-25
JP2009048925A2009-03-05
JP2009269987A2009-11-19
Other References:
J. AM.CHEM.SOC., vol. 128, 2006, pages 14256 - 14257
ANGEW. CHEM.INT.ED., vol. 48, 2009, pages 1576 - 1580
J.ORJ.CHEM., vol. 75, 2010, pages 4778 - 4785
J.PHYS.CHEM.C, 2008, pages 112 - 11691
J.AM.CHEM.SOC., vol. 103, 2008, pages 9202
J.PHYS.CHEM.B, vol. 109, 2005, pages 23776
Attorney, Agent or Firm:
NISHIZAWA Toshio (3-14, Kudan-kita 4-chome, Chiyoda-ku Tokyo 73, JP)
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Claims:
Claims

[Claim l]

An organic dye represented by the following general formula to which a donor site (D) and an acceptor site (A) are bound via linkers (Li)n

[Chemical formula l]

wherein ^ is an aromatic ring with or without heteroatom(s),

and wherein the donor site represented by the D is a triphenylamine derivative, a carbazole derivative, a coumarine derivative, or an indoline derivative, the A is the acceptor site which is an organic residue having an acidic group, and each of Li and L2 is a linker which is an optionally substituted divalent alkenyl group, aromatic group or heterocyclic group, and the n represents an integer of 0 to 3.

[Claim 2]

The organic dye according to claim 1, wherein the dye is a

4H-cyclopentadithiophene-4-one-based dye represented by the following general formula- [Chemical formula 2]

wherein the donor site D, the acceptor site A, the linkers Li and L2, and n is the same as defined above.

[Claim 3]

The organic dye according to claim 2, wherein the donor site D is a triphenylamine derivative represented by the following general formula^ [Chemical formula 3]

wherein the Rxs may be the same as, or different from one another, and are a phenyl group a para-position of which is substituted with a hydrogen atom, an alkyl group of a carbon number of 1 to 8 or an alkoxy group of a carbon number of 1 to 8, or an optionally substituted fluorenyl group or carbazole group, and the R2 is an optionally substituted phenylene group or

heterocyclic group.

[Claim 4]

The organic dye according to claim 2, wherein the donor site D is a carbazole derivative represented by the following general formula^

[Chemical formula 4]

wherein theR3 is a hydrogen atom, an alkyl group of a carbon number of 1 to 8, or an optionally substituted aromatic group or heterocyclic group. [Claim 5]

The organic dye according to claim 2, wherein the donor site D is a coumarine derivative represented by the following formula'- [Chemical formula 5]

wherein the R4s are hydrogen atoms or methyl groups.

[Claim 6]

The organic dye according to claim 2, wherein the donor site D indoline derivative represented by the following general formula^

[Chemical formula 6]

wherein the R5 is a hydrogen atom, an alkyl group of a carbon number of 1 to 8, an alkoxy group of a carbon number of 1 to 8, a trifluoromethyl group, or a 2, 2 dip he nyl vinyl group.

[Claim 7]

The organic dye according to any one of claims 2 to 6, wherein the acceptor site A is an organic residue having an acidic group.

[Claim 8]

The organic dye according to claim 7, wherein the acidic group is a carboxyl group.

[Claim 9]

The organic dye according to any one of claims 2 to 8, wherein each of the Li and the L2 is a linker which is an optionally substituted divalent alkenyl group, phenylene group or thiophenylene group, and the n

represents an integer of 0 to 3.

[Claim 10]

A dye -sensitized metal oxide semiconductor electrode, comprising a metal oxide semiconductor to which the organic dye according to any one of claims 2 to 9 is adsorbed.

[Claim 11]

A dye-sensitized solar cell characterized in that it includes, as a material to photoabsorb the solar light energy, at least one organic dye according to any of the claims 2 to 9.

[Claim 12]

The dye sensitized solar cell according to claim 11, comprising a dye -sensitized metal oxide semiconductor electrode wherein said organic dye(s) is (are) adsorbed.

[Claim 13]

The dye-sensitized solar cell according to claim 12 wherein a transparent electrode, the dye -sensitized metal oxide semiconductor electrode, an electrolyte and a counter electrode are sequentially laminated on a translucent support member.

[Claim 14]

The organic dye according to claim 1, wherein the dye is a

fluorenone -based dye represented by the following general formula^

[Chemical formula 7]

wherein the donor site D, the acceptor site A, the linkers Li and L2, and n is the same as defined above.

[Claim 15]

The organic dye according to claim 14, wherein the donor site D is a triphenylamine derivative represented by the following general formula^ [Chemical formula 8]

wherein the Rxs may be the same as, or different from one another, and are a phenyl group a para-position of which is substituted with a hydrogen atom, an alkyl group of a carbon number of 1 to 8 or an alkoxy group of a carbon number of 1 to 8, or an optionally substituted fluorenyl group or carbazole group, and the R2 is an optionally substituted phenylene group or

heterocyclic group.

[Claim 16] The organic dye according to claim 14, wherein the donor site D is a carbazole derivative represented by the following general formula:

[Chemical formula 9]

wherein theR3 is a hydrogen atom, an alkyl group of a carbon number of 1 to 8, or an optionally substituted aromatic group or heterocyclic group.

[Claim 17]

The organic dye according to claim 14, wherein the donor site D is a coumarine derivative represented by the following formula:

[Chemical formula 10]

wherein the R4s are hydrogen atoms or methyl groups.

[Claim 18]

The organic dye according to claim 14, wherein the donor site D indoline derivative represented by the following general formula^

[Chemical formula 11] wherein the R5 is a hydrogen atom, an alkyl group of a carbon number of 1 to 8, an alkoxy group of a carbon number of 1 to 8, a trifluoromethyl group, or a 2,2-diphenylvinyl group.

[Claim 19]

The organic dye according to any one of claims 14 to 18, wherein the acceptor site A is an organic residue having an acidic group.

[Claim 20]

The organic dye according to claim 19, wherein the acidic group is a carboxyl group.

[Claim 21]

The organic dye according to any one of claims 14 to 20, wherein each of the Li and the L2 is a linker which is an optionally substituted divalent alkenyl group, phenylene group or thiophenylene group, and the n

represents an integer of 0 to 3.

[Claim 22]

A dye-sensitized metal oxide semiconductor electrode, comprising a metal oxide semiconductor to which the organic dye according to any one of claims 14 to 21 is adsorbed.

[Claim 23] A dye-sensitized solar cell wherein a transparent electrode, the dye -sensitized metal oxide semiconductor electrode according to claim 22, an electrolyte and a counter electrode are sequentially laminated on a translucent support member.

Description:
Description

Title of Invention: ORGANIC DYE, DYE-SENSITIZED METAL OXIDE SEMICONDUCTOR ELECTRODE AND DYE-SENSITIZED SOLAR CELL Technical Field

The present invention relates to an organic dye which effectively photoabsorbs a solar light energy and can utilize it, as well as a

dye-sensitized metal oxide semiconductor electrode and a dye-sensitized solar cell utilizing this dye.

Background Art

In recent years, environmental problems including global warming due to increase in an amount of generated carbon dioxide by utilization of a fossil fuel such as a petroleum, a coal etc. are becoming serious. In place of this fossil fuel, utilization of a clean solar light energy which is infinite and does not generate harmful substances is being actively studied. Examples of a solar cell which can effectively convert solar light into electricity and has currently been put into practice include inorganic solar cells such as monocrystalline silicon, polycrystalline silicon, amorphous silicon and tellurated cadmium and selenized indium copper etc. for residences.

Examples of a defect of inorganic solar cells include, for example, in the case of a silicon-based solar cell, requirement of a very high purity, a purification step which is complex and has many processes, and the high manufacturing cost. Therefore, development of a new-type solar cell complementing these defects is desired. One of them includes development of a dye-sensitized solar cell. A dye used in the dye-sensitized solar cell at an initial stage is a ruthenium complex, and a high conversion efficiency has been obtained. However, since ruthenium is a rare metal, which is of limited source, and is of the high cost, stable supply is feared. In addition, this cell has a problem in stability with time and durability, and a new generation dye -sensitized solar cell containing, as a sensitizer, an organic dye without using this ruthenium, which is of the low cost, and is stable, and has an excellent conversion efficiency is actively studied.

For example, an organic dye having a basic structure of a [donor site -(n- spacer) -acceptor site] type has been developed. A dye in which a triphenylamine derivative, and a carbazole derivative are arranged in a donor site, and cyanoacrylic acid is arranged in an acceptor site, and they are connected with substituted bithiophene or polythiophene, has been disclosed. In a solar cell containing such the dye as a sensitizer, property is obtained to some extent, but a dye having further stability and an excellent conversion efficiency is desired.

Citation List

Patent Literature

PTL l: JP-A No. 2004-95450

PTL 2: JP-A No. 2009-48925

PTL 3: JP-A No. 2009-269987

Non Patent Literature

NPL l: J. Am.Chem.Soc.2006, 128, 14256-14257

NPL 2: Angew. Chem.Int.Ed.2009, 48, 1576-1580

NPL 3: Non- Patent Literature 3: J.Orj.Chem.2010, 75, 4778-4785.

NPL 4: Non-Patent Literature 4- J.Phys.Chem.C 2008, 112-11591.

NPL 5: Non- Patent Literature 5: J.Am.Chem.Soc.2008, 103, 9202. NPL 6: Non- Patent Literature 6: J.Phys.Chem.B 2005, 109, 23776.

Summary of Invention

Technical Problem

An object of the present invention is to provide an organic dye which is of the low price, is excellent in sensitivity to a wide visible light region, is stable, and has an excellent conversion efficiency, and a dye-sensitized solar cell using the same.

Solution to Problem

According to the present invention, an organic dye represented by the following general formula to which a donor site (D) and an acceptor site (A) are bound via linkers (Li)n and (I_2)n is provided:

[Chemical formula 1]

wherein ^is an aromatic ring with or without heteroatom(s),

and wherein the donor site represented by the D is a triphenylamine derivative, a carbazole derivative, a coumarine derivative, or an indoline derivative, the A is the acceptor site which is an organic residue having an acidic group, and each of Li and L2 is a linker which is an optionally substituted divalent alkenyl group, aromatic group or heterocyclic group, and the n represents an integer of 0 to 3.

According to one aspect of the present invention, a

4H-cyclopentadithiophene-4-one-based dye represented by the following chemical formula 2 to which a donor site (D) and an acceptor site (A) are bound via linkers (Li) n and (L2) n is provided:

[Chemical formula 2]

wherein the donor site D, the acceptor site A, the linkers Li and L2, and n is the same as defined above.

Herein, the donor site D may be a triphenylamine derivative represented by the following Chemical formula 3:

[Chemical formula 3]

wherein the R*s may be the same as, or different from one another, and are a phenyl group the para-position of which is substituted with a hydrogen atom, an alkyl group of a carbon number of 1 to 8 or an alkoxy group of a carbon number of 1 to 8, or an optionally substituted fluorenyl group or carbazole group, and the R 2 is an optionally substituted phenylene group or

heterocyclic group.

Alternatively, the donor site D may be a carbazole derivative represented by the following Chemical formula 4- [Chemical formula 4]

wherein the R 3 is a hydrogen atom, an alkyl group of a carbon number of 1 to 8, or an optionally substituted aromatic group or heterocyclic group.

Alternatively, the donor site D may be a coumarine derivative represented by the following Chemical formula 5:

[Chemical formula 5]

wherein the R 4 is a hydrogen atom or a methyl group.

Alternatively, the donor site D may be an indoline derivative represented by the following Chemical formula 6:

[Chemical formula 6]

wherein the R 5 is a hydrogen atom, an alkyl group of a carbon number of 1 to 8, an alkoxy group of a carbon number of 1 to 8, a trifluoromethyl group, or a 2,2-diphenylvinyl group.

In addition, the acceptor site A may be an organic residue having an acidic group.

Herein, the acidic group may be a carboxyl group.

In addition, each of the Li and the L2 may be a linker which is an optionally substituted divalent alkenyl group, phenylene group, or

thiophenylene group, and the n represents an integer of 0 to 3.

According to another aspect of the present invention, a dye-sensitized metal oxide semiconductor electrode comprising a metal oxide semiconductor to which any of the aforementioned 4H-cyclopentadithiophene-4-one-based dyes is adsorbed is provided.

According to still another aspect of the present invention, a dye-sensitized solar cell characterized in that it includes, as a material to photoabsorb the solar light energy, at least one aforementioned

4H-cyclopentadithiophene-4-one-based dye is provided.

Herein, the dye sensitized solar may comprise a dye-sensitized metal oxide semiconductor electrode wherein said

4H-cyclopentadithiophene-4"one-based dye(s) is (are) adsorbed.

In addition, the dye-sensitized solar cell may be provided wherein a transparent electrode, the aforementioned dye-sensitized metal oxide semiconductor electrode, an electrolyte, and a counter electrode are sequentially laminated on a translucent support member.

Also, according to still another aspect of the present invention, a fluorenone -based dye represented by the following chemical formula 7 to which a donor site (D) and an acceptor site (A) are bound via linkers (L 1 ) n and (L2) n is provided :

[Chemical formula 7]

wherein the donor site D, the acceptor site A, the linkers Li and L2, and n is the same as defined above.

Herein, the donor site D may be a triphenylamine derivative represented by the following Chemical formula 8:

[Chemical formula 8]

wherein the E s may be the same as, or different from one another, and are a phenyl group the para-position of which is substituted with a hydrogen atom, an alkyl group of a carbon number of 1 to 8 or an alkoxy group of a carbon number of 1 to 8, or an optionally substituted fluorenyl group or carbazole group, and the R 2 is an optionally substituted phenylene group or

heterocyclic group.

Alternatively, the donor site D may be a carbazole derivative represented by the following Chemical formula 9^

[Chemical formula 9]

wherein the R 3 is a hydrogen atom, an alkyl group of a carbon number of 1 to 8, or an optionally substituted aromatic group or heterocyclic group.

Alternatively, the donor site D may be a coumarine derivative represented by the following Chemical formula 10:

[Chemical formula 10]

wherein the R 4 is a hydrogen atom or a methyl group.

Alternatively, the donor site D may be an indoline derivative represented by the following Chemical formula 11:

[Chemical formula 11]

wherein the R 5 is a hydrogen atom, an alkyl group of a carbon number of 1 to 8, an alkoxy group of a carbon number of 1 to 8, a trifluoromethyl group, or a 2,2-diphenylvinyl group.

In addition, the acceptor site A may be an organic residue having an acidic group.

Herein, the acidic group may be a carboxyl group.

In addition, each of the Li and the L2 may be a linker which is an optionally substituted divalent alkenyl group, phenylene group, or

thiophenylene group, and the n represents an integer of 0 to 3.

According to another aspect of the present invention, a dye-sensitized metal oxide semiconductor electrode comprising a metal oxide semiconductor to which any of the aforementioned fluorenone -based dyes is adsorbed is provided.

According to still another aspect of the present invention, a dye -sensitized solar cell characterized in that it includes, as a material to photoabsorb the solar light energy, at least one aforementioned

fluorenone-based dye is provided.

Herein, the dye sensitized solar may comprise a dye-sensitized metal oxide semiconductor electrode wherein said fluorenone-based dye(s) is (are) adsorbed.

In addition, the dye -sensitized solar cell may be provided wherein a transparent electrode, the aforementioned dye -sensitized metal oxide semiconductor electrode, an electrolyte, and a counter electrode are sequentially laminated on a transparent support member.

Advantageous Effects of Invention

According to the present invention, an organic dye which is a sensitizing dye having a basic structure of a [donor site-(n-spacer)-acceptor site] type, and has more excellent property than the existing dye, and a dye-sensitized solar cell utilizing the same are provided.

Brief Description of Drawings

[Fig. l] Fig. 1 is a drawing showing light absorption spectra of dyes NSQl, NSQ2, NSQ3, NSQ4, NSQ5 and NSQ6 of the examples of the present invention.

[Fig. 2] Fig. 2 is a drawing showing light absorption spectra of dyes NSQ7,

NSQ8, NSQ9 and NSQ10 of the examples of the present invention.

[Fig. 3] Fig. 3 is a drawing showing light absorption spectra of dyes HIQF1,

HIQF2, HIQF3, HIQF4, and HIQF5 of the examples of the present

invention.

Description of Embodiments

1. 4H-cyclopentadithiophene-4-one-based dye

In order to solve the problems, the present inventors intensively studied and, as a result, newly synthesized a substance which is suitable for use as an organic dye for a dye-sensitized solar cell, and comprises a chromophore giving a small HOMO-LUMO band gap. More specifically, this substance is an organic compound which is constructed of an electron donating site, a n-conjugated crosslinked part, and an electron accepting site, and has a particular structure at the n-conjugated crosslinked part.

In one aspect, the dye of the present invention is a compound which has a donor site (electron donating group) on an end, and an acceptor site (electron accepting group) on another end, and is constructed of

4H-cyclopentadithiophene-4-one, and a n-conjugated crosslinked part with an alkenyl group, an aromatic group, and a heterocyclic group connected thereto, therebetween, and is specifically a novel

4H _ cyclopentadithiophene-4-one-based dye represented by Chemical formula 12 which is the general formula.

[Chemical formula 12]

In the general formula (Chemical formula 12), a donor site

represented by D represents a triphenylamine derivative, a carbazole derivative, a coumarine derivative, or an indoline group, and A is an acceptor site and represents an organic residue having an acidic group. Each of Li and Li2 is a linker which is an optionally substituted divalent alkenyl group, aromatic group or heterocyclic group, and n represents an integer of 0 to 3.

Also, the present invention provides a dye constructed of a

triphenylamine derivative, a carbazole derivative, a coumarine derivative, or an indoline derivative, respectively, represented by Chemical formula 13, Chemical formula 14, Chemical formula 15 or Chemical formula 16 which is the following general formula, as a donor site.

[Chemical formula 13]

In the general formula (Chemical formula 13), R^s may be the same as, or different from one another, and represent a phenyl group in which a para-position is substituted with a hydrogen atom, an alkyl group of a carbon number of 1 to 8, or an alkoxy group of a carbon number of 1 to 8, or an optionally substituted fluorenyl group or carbazole group. R 2 represents an optionally substituted phenylene group or heterocyclic group.

[Chemical formula 14]

In the general formula (Chemical formula 14), R 3 represents a hydrogen atom, an alkyl group of a carbon number of 1 to 8, an optionally substituted aromatic group or heterocyclic group.

[Chemical formula 15]

In Chemical formula 15, R 4 represents a hydrogen atom or a methyl group.

[Chemical formula 16]

In Chemical formula 16, R 5 is a hydrogen atom, an alkyl group of a carbon number of 1 to 8, an alkoxy group of a carbon number of 1 to 8, a trifluoromethyl group, or a 2,2-diphenylvinyl group.

Examples of the donor site D in Chemical formula 12 are listed below.

[Chemical formula 17]

In the aforementioned formulas,

[Chemical formula 18]

R 6 = H

R 7 = CH 3 , C 2 H 5 , C 4 H 9I C(CH 3 ) 3 , C 8 H 17 , OCH 3, OC 2 H 5 OC 4 H 9,

OC 8 H 17] OCH 2 CH(CH 2 ) 3 CH 3

I

C 2 H 5

or H, CH 3 , C 2 H 5 , C 4 H 9 , C 8 H 17 , OCH 3, 0C 2 H 5| OC 4 H 9, OC 8 H OCH 2 CH(CH 2 )3CH 3

2 n 5

[Chemical formula 19]

[Chemical formula 20]

Chemical formula 21]

Herein,

[Chemical formula 22]

[Chemical formula 23]

In addition, in Chemical formula 12 which is the general formula, an acceptor site represented by A is an organic residue having an acidic group and, as the acidic group, a carboxyl group is preferable. In addition, in a linker site represented by (La) n or (L2) n, each of Li and L2 is an optionally substituted divalent alkenyl group, phenylene group or thiophenylene group, and n represents an integer of 0 to 3.

Examples of the acceptor site A are shown below.

[Chemical formula 24]

In addition, examples of Li and L2 of a linker site represented by

(Li)n or (L2)n are shown below. Herein, n represents an integer of 0 to 3. [Chemical formula 25]

A method of synthesizing a dye represented by the general formula (Chemical formula 12) of the present invention is not particularly limited, but for example, 4H yclopentadithiophene-4-one can be derived into a synthetic intermediate,

6-bromo-4H-cyclopenta[2,l-b:3,4-b']dithiophene-4"one-2-carba ldehyde by a Vilsmeier reaction, or a brominating reaction using NBS, this can be connected with D (donor site)-L (linker) by a Stille, Suzuki or Negishi coupling reaction, and can be connected with A (acceptor site) by a

Knoevenagel condensing reaction. Alternatively, L (linker) -A (acceptor site) can be connected by a Wittig reaction or a Horner-Wadsworth-Emmons reaction. Alternatively, after connection between

4H-cyclopentaditihophene-4-one and a D-L part, a L-A part can be connected by the aforementioned coupling reaction. A triphenylamine derivative, a carbazole derivative, a coumarine derivative, or an indoline derivative of D (donor site) can be synthesized by methods described in Non-Patent

Literatures 4 to 6, respectively.

The dye of the present invention has an excellent structure in a n-conjugated crosslinked part, and D (donor site) and A (acceptor site) are connected with a 2-position and 6-position of

4H-cyclopentadithiophene-4-one via Li or L2 (linker). In ultraviolet and visible absorption spectra of the dye, a maximum absorption wavelength is shifted to a long wavelength side, and sensitivity to visible right is improved.

Then, the dye-sensitized solar cell of the present invention will be explained. The dye-sensitized solar cell of the present invention uses the 4H-cyclepentadithiophene-4-one-based organic dye of the present invention as a dye sensitizer.

Specifically, the dye -sensitized solar cell of the present invention is constructed by sequentially laminating a dye -sensitized metal oxide semiconductor electrode, an electrolyte and a counter electrode on an electrically conductive support. The dye of the present invention is chemically adsorbed on the dye -sensitized metal oxide semiconductor electrode. As the electrically conductive support, a metal, or a glass or a plastic etc. having an electrically conductive layer on a surface can be used. Examples of the electrically conductive layer include metals such as gold, platinum, silver, copper, indium etc., electrically conductive carbon, indium tin oxide, tin oxide doped with fluorine etc. Using these electrically conductive materials, the electrically conductive layer can be formed on a surface of a support by the conventional method. In addition, when an electrically conductive support side is a light receiving surface, it is

preferable that the electrically conductive support is transparent.

Examples of a material constituting the oxide semiconductor electrode include titanium oxide, niobium oxide, zinc oxide, tin oxide, tungsten oxide, indium oxide etc. Among them, preferable are titanium oxide, niobium oxide, and tin oxide, and particularly preferable is titanium oxide. The oxide semiconductor electrode can be formed by forming fine particles of those oxides, suspending this in a suitable solvent, coating the suspension on a transparent electrically conductive glass, removing the solvent, and heating this.

In order to adsorb the dye on the oxide semiconductor electrode, adsorption can be performed by soaking an electrode in a dye solution. A solvent of the dye solution is a solvent which dissolves the dye, and preferable examples include alcohol-based solvents such as methanol, ethanol, butanol, t-butyl alcohol etc., nitrile-based solvents such as acetonitrile etc., ketone-based solvents such as acetone, methyl ethyl ketone etc., ether-based solvents such as diethyl ether, diisopropyl ether,

tetrahydrofuran, 1,4-dioxane etc., halogenated hydrocarbon solvents such as methylene chloride, 1,1,2-trichloroethane etc., or a mixed solvent of them. Particularly preferable are acetonitrile, an acetonitrile -methanol mixed solvent, methanol, ethanol, acetone, methyl ethyl ketone, tetrahydrofuran, methylene chloride and a mixed solvent of them. It is preferable that a concentration of an organic dye solution is around 0.1 to lOmM. A soaking time is appropriately adjusted depending on an organic dye used, a kind of a solvent, a concentration of a solution etc., and 0.5 to 30 hours is preferable, and 2 to 25 hours is further preferable. A temperature upon soaking is preferably 0 to 100°C, further preferably 10 to 50°C.

The electrolyte contains an electrically conductive material which can transport electrons, holes and ions. As the electrically conductive material, an ion conducting body is preferable, and a solution or a solid or an ionic liquid containing a redox series can be used. Specifically, examples of the redox series include I7l3 " series, Br2/Br3 ' sereis, Co 2+ /Co 3+ series, Fe 2+ /Fe 3+ series etc., and examples of the solvent include nitrile-based compounds such as acetonitrile, carbonate-based compounds such as propylene carbonate etc. In addition, examples of an additive of the liquid electrolyte include nitrogen-containing aromatic compounds such as 4-t-butylpyridine, or imidazolium salts such as (l,2-dimethyl-3-propyl) imidazolium iodide which have previously been used, and these additives may be added to the liquid electrolyte at a concentration of around 0.1 to 1.5 M.

The dye -sensitized solar cell of the present invention has a

lamination structure in which the anode and the cathode are provided, and the electrolyte fills therebetween. Herein, by fixation in the state where a spacer is held between the anode and the cathode, both electrodes can be faced at an arbitrary interval.

2. Fluorenone -based dye

In another aspect, the dye of the present invention is a compound which has a donor site (electron donating group) on an end, and an acceptor site (electron accepting group) on another end, and is constructed of fluorenone, and a n-conjugated crosslinked part with an alkenyl group, an aromatic group, and a heterocyclic group connected thereto, therebetween, and is specifically a novel fluorenone -based dye represented by Chemical formula 26 which is the general formula.

[Chemical formula 26]

In the general formula (Chemical formula 26), a donor site

represented by D represents a triphenylamine derivative, a carbazole derivative, a coumarine derivative, or an indoline group, and A is an acceptor site and represents an organic residue having an acidic group. Each of Li and L2 is a linker which is an optionally substituted divalent alkenyl group, aromatic group or heterocyclic group, and n represents an integer of 0 to 3.

Also, the present invention provides a dye constructed of a

triphenylamine derivative, a carbazole derivative, a coumarine derivative, or an indoline derivative, respectively, represented by Chemical formula 27, Chemical formula 28, Chemical formula 29 or Chemical formula 30 which is the following general formula, as a donor site.

[Chemical formula 27]

In the general formula (Chemical formula 27), R s may be the same as, or different from one another, and represent a phenyl group in which a para-position is substituted with a hydrogen atom, an alkyl group of a carbon number of 1 to 8, or an alkoxy group of a carbon number of 1 to 8, or an optionally substituted fluorenyl group or carbazole group. R 2 represents an optionally substituted phenylene group or heterocyclic group.

[Chemical formula 28]

In the general formula (Chemical formula 28), R 3 represents a hydrogen atom, an alkyl group of a carbon number of 1 to 8, an optionally substituted aromatic group or heterocyclic group.

[Chemical formula 29]

In Chemical formula 29, R 4 represents a hydrogen atom or a methyl group.

[Chemical formula 30]

In Chemical formula 30, R 5 is a hydrogen atom, an alkyl group of a carbon number of 1 to 8, an alkoxy group of a carbon number of 1 to 8, a trifluoromethyl group, or a 2, 2 - dip he nyl vinyl group.

Examples of the donor site D in Chemical formula 26 are listed below.

[Chemical formula 31]

In the aforementioned formulas,

[Chemical formula 32]

R 6 = H

R 7 = CH 3l C 2 H 5 , C 4 H 9 , C(CH 3 ) 3 , C 8 H 17l OCH 3, OC 2 H 5, OC 4 H 9, OC 8 H 17 OCH 2 CH(CH 2 )3CH3

I

C 2 H 5 or

R 6 =R 7 = H, CH 3 , C 2 H 5 , C 4 H 9 , C 8 H 17> OCH 3, OC 2 H 5, OC 4 H 9, OC 8 H 17

OCH 2 CH(CH 2 )3CH3

C 2 H 5

[Chemical formula 33]

[Chemical formula 34]

[Chemical formula

[Chemical formula 37]

In addition, in Chemical formula 26 which is the general formula, an acceptor site represented by A is an organic residue having an acidic group and, as the acidic group, a carboxyl group is preferable. In addition, in a linker site represented by (Li) n or (L2) n, each of Li and L2 is an optionally substituted divalent alkenyl group, phenylene group or thiophenylene group, and n represents an integer of 0 to 3.

Examples of the acceptor site A are shown below.

[Chemical formula 38]

In addition, examples of Li and L2 of a linker site represented by (Li)n or (L2)n are shown below. Herein, n represents an integer of 0 to 3. [Chemical formula 39]

A method of synthesizing a dye represented by the general formula (Chemical formula 26) of the present invention is not particularly limited, but for example, 2,7-dibromo-9H-fluoren-9-one can be utilized as a synthetic intermediate, this can be connected with D (donor site), D- Li (linker), and L2 by a Stille, Suzuki or Negishi coupling reaction, and can be connected with A (acceptor site) by a Knoevenagel condensing reaction. A triphenylamine derivative, a carbazole derivative, a coumarine derivative, or an indoline derivative of D (donor site) can be synthesized by methods described in Non-Patent Literatures 4 to 6, respectively.

The dye of the present invention has an excellent structure in a n-conjugated crosslinked part, and D (donor site) and A (acceptor site) are connected with a 2-position and 7-position of 9H-fluoren-9-one via Li or L2 (linker). In ultraviolet and visible absorption spectra of the dye, a

maximum absorption wavelength is shifted to a long wavelength side, and sensitivity to visible right is improved.

Then, the dye-sensitized solar cell of the present invention will be explained. The dye-sensitized solar cell of the present invention uses the fluorenone-based organic dye of the present invention as a dye sensitizer.

Specifically, the dye-sensitized solar cell of the present invention is constructed by sequentially laminating a dye-sensitized metal oxide semiconductor electrode, an electrolyte and a counter electrode on an electrically conductive support. The dye of the present invention is chemically adsorbed on the dye-sensitized metal oxide semiconductor electrode. As the electrically conductive support, a metal, or a glass or a plastic etc. having an electrically conductive layer on a surface can be used. Examples of the electrically conductive layer include metals such as gold, platinum, silver, copper, indium etc., electrically conductive carbon, indium tin oxide, tin oxide doped with fluorine etc. Using these electrically conductive materials, the electrically conductive layer can be formed on a surface of a support by the conventional method. In addition, when an electrically conductive support side is a light receiving surface, it is preferable that the electrically conductive support is transparent.

Examples of a material constituting the oxide semiconductor electrode include titanium oxide, niobium oxide, zinc oxide, tin oxide, tungsten oxide, indium oxide etc. Among them, preferable are titanium oxide, niobium oxide, and tin oxide, and particularly preferable is titanium oxide. The oxide semiconductor electrode can be formed by forming fine particles of those oxides, suspending this in a suitable solvent, coating the suspension on a transparent electrically conductive glass, removing the solvent, and heating this.

In order to adsorb the dye on the oxide semiconductor electrode, adsorption can be performed by soaking an electrode in a dye solution. A solvent of the dye solution is a solvent which dissolves the dye, and preferable examples include alcohol-based solvents such as methanol, ethanol, butanol, t-butyl alcohol etc., nitrile-based solvents such as acetonitrile etc., ketone -based solvents such as acetone, methyl ethyl ketone etc., ether-based solvents such as diethyl ether, diisopropyl ether,

tetrahydrofuran, 1,4-dioxane etc., halogenated hydrocarbon solvents such as methylene chloride, 1,1,2-trichloroethane etc., or a mixed solvent of them. Particularly preferable are acetonitrile, an acetonitrile-methanol mixed solvent, methanol, ethanol, acetone, methyl ethyl ketone, tetrahydrofuran, methylene chloride and a mixed solvent of them. It is preferable that a concentration of an organic dye solution is around 0.1 to lOmM. A soaking time is appropriately adjusted depending on an organic dye used, a kind of a solvent, a concentration of a solution etc., and 0.5 to 30 hours is preferable, and 2 to 25 hours is further preferable. A temperature upon soaking is preferably 0 to 100°C, further preferably 10 to 50°C.

The electrolyte contains an electrically conductive material which can transport electrons, holes and ions. As the electrically conductive material, an ion conducting body is preferable, and a solution or a solid or an ionic liquid containing a redox series can be used. Specifically, examples of the redox series include IWseries, Br2/Br3 ' sereis, Co 2+ /Co 3+ series, Fe 2+ /Fe 3+ series etc., and examples of the solvent include nitrile-based compounds such as acetonitrile, carbonate -based compounds such as propylene carbonate etc. In addition, examples of an additive of the liquid electrolyte include nitrogen-containing aromatic compounds such as 4-t-butylpyridine, or imidazolium salts such as (l,2-dimethyl-3-propyl) imidazolium iodide which have previously been used, and these additives may be added to the liquid electrolyte at a concentration of around 0.1 to 1.5 M.

The dye-sensitized solar cell of the present invention has a

lamination structure in which the anode and the cathode are provided, and the electrolyte fills therebetween. Herein, by fixation in the state where a spacer is held between the anode and the cathode, both electrodes can be faced at an arbitrary interval.

Examples The present invention will be explained specifically by way of the following Examples, but the present invention is not limited to them.

Example 1

(Synthesis Example l)

According to the following scheme,

2-Cyano-3-{6-{2-{4-[N,N-bis(4-methylphenyl)amino]phenyl}t hiophen-5-yl}'4 H-cyclopenta[2,l-b:3,4-b']dithiophene-4-one-2-yl}acrylic acid (NSQl) was obtained.

Chemical formula 40]

1

[Chemical formula 41]

o Synthesis of

6"Bromo-4H-cyclopenta[2,l-b:3,4-b']dithiophene-4-one-2-carba ldehyde (2) (An alpha-numeric sequence with a parenthesis immediately after a substance name shows a substance with corresponding an alpha-numeric sequence in Chemical formulas 23 to 28. The same hereinafter.) (see Chemical formula 40.)

A solution of 4H-cyclopentadithio hene-4-one (4.51 g, 23.4 mmol) and DMF (1.86 g, 25.74 mmol) in dichloromethane (60 ml) was cooled to 0°C, and phosphorus oxychloride (3.95 g, 25.74 mmol) was added dropwise at 0 to 5°C. After completion of addition, the reaction solution was heated to 80°C, and stirred for 6 hours. An aqueous saturated sodium acetate solution (100 ml) was added, the mixture was stirred at room temperature for 30 minutes, water (100 ml) was added to the reaction solution, and the crude product was extracted with dichloromethane, dried with magnesium sulfate, and concentrated under reduced pressure. The residues was purified by silica gel column chromatography (ethyl acetate/hexane = 1/10) to obtain

4H-cyclopenta[2,l-b:3,4-b']dithiophene-4-one-2-carbaldehy de (l) as a dark red solid substance (4.7 g, 91%).

Ή NMR (600MHz, DMSO-d 6 ) δ: 9.79 (s, 1H), 7.93 (s, 1H), 7.68 (d, J = 4.8Hz, 1H), 7.18 (d, J = 4.8Hz, 1H).

This aldehyde (l) (4.6 g, 20.9 mmol) was dissolved in DMF (50 ml), NBS (4.6 g, 20.9 mmol) was added under the nitrogen atmosphere while light was shielded, and the mixture was stirred at room temperature for 12 hours. To the reaction solution was added water (200 ml), and the crude product was extracted with dichloromethane (200 ml x 3), dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate/hexane = 1/10) to obtain 6 -bromo - 4H-cyclopenta [2, 1 -b :

3,4-b']dithiophene-4-one-2-carbaldehyde (2) as a faint red solid substance (6.0 g, 96%).

Ή NMR (600MHz, CDC1 3 )8: 9.79 (s, 1H), 7.61 (s, 1H), 7.12 (s, 1H), 7.18 (d, J = 4.8Hz, 1H).

o Synthesis of

2-Cyano-3-{6-{2-{4-[N,N-bis(4-methylphenyl)amino]phenyl}thio phen-5-yl}"4 H-cyclopenta[2,l-b:3,4-b']dithiophene-4-one-2-yl}acrylic acid (NSQl) (see Chemical formula 41) 4,4'-Dimethyltriphenylamine (5.6 g, 20.4 mmol) was dissolved in DMF (25 ml), and a solution of NBS (3.6 g, 20.4 mmol) in DMF (25 ml) was added dropwise. After completion of addition, the mixture was stirred at room temperature overnight. Water (100 ml) was added to the reaction solution, and the crude product was extracted with diethyl ether, dried with magnesium sulfate and concentrated under reduced pressure. The green oily residue was treated with methanol to crystallize to obtain

4-bromo-N,N-bis(4-methylphenyl)aniline (3) (4.9 g, 74%).

Ή NMR (600MHz, CDC1 3 ) 8: 7.43 (d, J = 8.4Hz, 2H), 7.19 (m, 2H), 7.06 (d, J = 8.4Hz, 4H), 7.01 (d, J = 8.4Hz, 4H), 2.31 (s, 6H).

This aniline (3) (3.57 g, 10 mmol), tributyl(2"thienyl)tin (4.48 g, 12 mmol) and tetrakis(triphenylphosphine)palladium (Pd(PPh3)4) (100 mg) were suspended in dry toluene (50 ml), and the resulting mixture was heated to reflux for 16 hours under the argon atmosphere. After completion of the reaction, water (120 ml) was added to the reaction solution, and the crude product was extracted with dichlorome thane, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane) to obtain

4-(thiophen-2-yl)-N,N-bis(4-methylphenyl)aniline (4) as a white solid (3.1 g, 86%).

Ή NMR (600MHz, CDCI3) 6: 7.32 (d, J = 6.6Hz, 2H), 7.08 (d, J = 8.4Hz, 4H), 6.99 (m, 7H), 6.91 (d, J = 3.6Hz, 1H), 6.74 (d, J = 6.6Hz, 1H), 2.31 (s, 6H).

This aniline (4) (0.355 g, 1 mmol) was dissolved in dry THF (20 ml), the solution was cooled to -78°C under the argon atmosphere, and

n-butylbutyllithium (1.6M hexane solution) (0.68 ml) was added dropwise over 15 minutes. After completion of addition, the mixture was stirred at 78°C for 1 hour, and tributyltin chloride (0.39 g, 1.2 mmol) was added dropwise for 10 minutes. Thereafter, stirring was continued overnight, and a reaction temperature was returned to room temperature. Water (50ml) was added to the reaction solution, and the crude product was extracted with ethyl acetate, dried with magnesium sulfate, and concentrated under reduced pressure to obtain

4-[5-(tributylstannyl)thiophen-2-yl]-N,N-bis(4-methylphenyl) aniline (5) as a colorless oil (0.56 g, 88%).

Ή NMR (600MHz, CDC1 3 ) δ-' 7.34 (d, J = 6.6Hz, 2H), 7.06 (d, J = 8.4Hz, 4H), 6.98 (m, 7H), 6.93 (d, J = 3.6Hz, 1H), 6.74 (d, J = 6.6Hz, 1H), 2.33 (s, 6H), 1.62-1.48 (m, 6H); 1.38-1.22 (m, 6H); 1.08 (t, 9H); 0.91 (q, 6H).

The aldehyde (2) (0.19 g, 0.65 mmol), aniline (5) (0.52 g, 0.8 mmol) and Pd(PPh.3)4(lO mg) were dissolved in dry toluene (30 ml), and the solution was heated to reflux for 24 hours under the argon atmosphere. To the reaction solution was added water (50 ml), and the crude product was extracted with dichloromethane, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate/hexane = l/lO) to obtain

6-{5-{4-[N,N-bis(4-methylphenyl)amino]phenyl}thiophen-2-y l}-4H-cyclepenta [2,l-b:3,4-b']dithiophene-4-one-2-carbaldehyde (6) (0.28 g, 75%).

NMR (600MHz, CDCI3) 8: 9.77 (s, 1H), 7.40 (d, J = 6.6Hz, 2H), 7.18 (d, J = 3.6Hz, 2H), 7.13 (m, 2H), 7.09 (d, J = 8.4Hz, 4H), 7.03 (m, 6H), 2.32 (s, 6H).

This aldehyde (6) (0.22 g, 0.4 mmol) and cyanoacetic acid (68 mg, 0.8 mmol) were dissolved in chloroform (50 ml), piperidine (0.14 g, 1.6 mmol) was added, and the resulting mixture was heated to reflux for 12 hours under the argon atmosphere. To the reaction solution was added 2N hydrochloric acid (10 ml), water (80 ml) was added, and the crude product was extracted with chloroform, dried with magnesium sulfate, and

concentrated under reduced pressure. The residue was purified by silica gel column chromatography (methanol/chloroform = 1/10) to obtain

2-cyano-3-{6-{2-{4-[N,N-bis(4-methylphenyl)amino]phenyl}t hiophen-5-yl}-4H cyclopenta[2,l-b:3,4-b']dithiophene-4-one-2-yl}acrylic acid (NSQl) as a dark red solid (0.15 g, 60%).

NMR (600MHz, DMSO-d 6 ) 8: 8.06 (s, 1H), 7.58 (s, 1H), 7.49 (d, J = 8.4Hz, 2H), 7.39 (d, J = 4.2Hz, 1H), 7.33 (d, J = 4.2Hz, 1H), 7.29 (s, 1H), 7.13 (d, J = 8.4Hz, 4H), 6.94 (d, J = 8.4Hz, 4H), 6.87 (d, J = 8.4Hz, 2H), 2.27 (s, 6H).

(Synthesis Example 2)

According to the following scheme,

2-Cyano-3-{6-{2-{4-[N,N-bis(4-methylphenyl)amino]phenyl}- 3,4-ethylenediox ythiophen-5-yl}-4H-cyclopenta[2,l-b ' -3,4-b']dithiophene-4-one-2'yl}acrylic acid (NSQ2) was obtained.

[Chemical formula 42]

o Synthesis of

2-Cyano-3-{6-{2-{4-[N,N-bis(4-methylphenyl)amino]phenyl}-3,4 -ethylenediox ythiophen-5-yl}-4H-cyclopenta[2,l"b:3,4-b']dithiophene-4-one -2-yl}acrylic acid (NSQ2) (see Chemical formula 42)

3,4-Ethylenedioxythiophene (2.0 g, 14 mmol) was dissolved in dry THF (150 ml), the solution was cooled to -78°C under the argon atmosphere, and n-butyllithium (1.6M hexane solution) (10 ml, 1.62 mmol) was added dropwise for 30 minutes. After completion of addition, a temperature was risen to -40°C, the mixture was stirred for 30 minutes, and tributyltin chloride (5.95 g, 18.8 mmol) was added dropwise for 10 minutes. Thereafter, stirring was continued for 12 hours while a temperature was returned to room temperature. To the reaction solution was added water (300 ml), and the crude product was extracted with ethyl acetate, dried with magnesium sulfate, and concentrated under reduced pressure to obtain

2-(tributylstannyl)-3,4-(ethylenedioxy)thiophene (7) as a yellow oil (0.57 g, 88%).

Ή NMR (600MHz, CDC1 3 ) 8: 6.58 (s, 1H); 4.15 (s, 4H); 1.63-1.49 (m, 6H); 1.38-1.22 (m, 6H); 1.09 (t, 9H); 0.91 (q, 6H).

The aniline (3) (0.63 g, 1.8 mmol), thiophene (7) (0.86 g, 2 mmol) and Pd(PPh.3)4 (20 mg) were suspended in dry toluene (20 ml), and the suspension was heated to reflux for 24 hours under the argon atmosphere. After completion of the reaction, water (30 ml) was added to the reaction solution, and the crude product was extracted with dichloromethane, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (dichloromethane/hexane = 1/20) to obtain

4-(3,4-ethylenedioxythiophen-2-yl)-N,N-bis(4-methylphenyl)an iline (8) as a yellow oily solid (0.6 g, 80%).

Ή NMR (600MHz, CDCI3) δ: 7.42 (d, J = 6.6Hz, 2H), 7.08 (d, J = 8.4Hz, 4H), 6.99 (m, 7H), 6.92 (d, J = 3.6Hz, 1H), 6.48 (s, 1H), 4.26 (m, 2H), 4.24 (m, 2H), 2.32 (m, 6H).

This aniline (8) (0.33 g, 0.8 mmol) was dissolved in dry THF (20 ml), the solution was cooled to -78°C under the argon atmosphere, and

n-butylbutyllithium (1.6M hexane solution) (0.68 ml) was added dropwise over 15 minutes. After addition, the mixture was stirred at -78°C for 1 hour, and tributyltin chloride (0.29 g, 0.9 mmol) was added dropwise over 10 minutes. Thereafter, stirring was continued overnight, and a temperature was returned to room temperature. To the reaction solution was added water (10 ml), and the crude product was extracted with ethyl acetate, dried with magnesium sulfate and concentrated under reduced pressure to obtain 4-[5-tributylstannyl-3,4-ethylenedioxythiophen-2-yl]-N,N-bis (4-methylpheny Oaniline (9) as a colorless oil (0.46 g, 82%).

Ή NMR (600MHz, CDCls) δ: 7.42 (d, J = 6.6Hz, 2H), 7.08 (d, J = 8.4Hz, 4H), 6.99 (m, 7H), 6.92 (d, J = 3.6Hz, 1H), 6.48 (s, 1H), 4.26 (m, 2H), 4.24 (m, 2H), 2.32 (m, 6H), 1.62-1.48 (m, 6H); 1.38-1.22 (m, 6H); 1.10 (t, 9H); 0.89 (q, 6H).

This aniline (9) (0.19 g, 0.65 mmol), the aldehyde (2) (0.28 g, 0.4 mmol) and Pd(PPh3)4 (l0 mg) were dissolved in dry toluene (20 ml), and the solution was heated to reflux for 24 hours under the argon atmosphere. To the reaction solution was added water (50 ml), and the crude product was extracted with dichloromethane, dried with magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate/hexane = 1/10) to obtain

6-{5-{4-[N,N-bis(4-methylphenyl)amino]phenyl}-3,4-ehylene dioxythiophen-2- yl}-4H-cyclopenta[2,l-b:3,4-b']dithiophene-4-one-2-carbaldeh yde (lO) (0.15 g, 68%).

Ή NMR (600MHz, CDCI3) δ: 9.74 (s, 1H), 7.53 (m, 3H), 7.16 (s, 1H), 7.08 (d, J = 7.8Hz, 4H), 7.02 (m, 6H), 4.41 (s, 2H), 4.36 (s, 2H), 2.32 (s, 6H).

The aldehyde (lO) and cyanoacetic acid were treated as in Synthesis Example 1 to obtain

2-Cyano-3-{6"{2-{4-[N,N-bis(4-methylphenyl)amino]phenyl}-3,4 -ethylenediox ythiophen-5-yl}-4H-cyclopenta[2,l-b: 3,4-b']dithiophene-4-one-2-yl}acrylic acid (NSQ2) (yield 55%).

Ή NMR (600MHz, DMSO-d 6 ) 6: 8.08 (s, 1H), 7.61 (s, 1H), 7.50 (s, 2H), 7.12 (m, 5H), 6.93 (m, 6H), 4.45 (s, 2H), 4.37 (s, 2H), 2.27 (s, 6H).

(Synthesis Example 3)

According to the following scheme,

2-Cyano-3-{6-{4-[N,N-bis(4-methylphenyl)amino]phenyl}-4H- cyclopenta[2,l- b: 3,4-b']dithiophene-4-one-2-yl}acrylic acid (NSQ3) was obtained.

[Chemical formula 43]

o Synthesis of

2-Cyano-3-{6-{4-[N,N-bis(4-methylphenyl)amino]phenyl}-4H-cyc lopenta[2,l- b:3,4-b']dithiophene-4-one-2-yl}acrylic acid (NSQ3) (see Chemical formula 23)

The aniline (3) (0.28g, 0.8 mmol) was dissolved in dry THF (20 ml), the solution was cooled to _ 78°C under the argon atmosphere, and

n-butyllithium (1.6 M hexane solution) (0.68 ml) was added dropwise over 15 minutes. After completion of addition, the mixture was stirred at -78°C for 1 hour, and tributyltin chloride (0.29 g, 0.9 mmol) was added dropwise over 10 minutes. Thereafter, stirring was continued overnight, and a

temperature was returned to a reaction temperature. To the reaction solution was added water (10 ml), and the crude product was extracted with ethyl acetate, dried with magnesium sulfate, and concentrated under reduced pressure to obtain

4-tributylstannyl-N,N-bis(4-methylphenyl)aniline(ll) as a colorless oil (0.37g, 83%).

*H NMR (600MHz, CDCls) 6: 7.43 (d, J = 8.4Hz, 2H), 7.19 (m, 2H), 7.06 (d, J = 8.4Hz, 4H), 7.01 (d, J = 8.4Hz, 4H), 2.31 (s, 6H), 1.63-1.48 (m, 6H);l.38-1.21 (m, 6H);l.09 (t, 9H);0.90 (q, 6H).

This aniline (11) (0.22 g, 0.4 mmol), the aldehyde (2) (O.l g, 0.35 mmol) and Pd(PPhs)4 (10 mg) were dissolved in dry toluene (20 ml), and the solution was heated to reflux for 24 hours under the argon atmosphere. To the reaction solution was added water (50 ml), and the crude product was extracted with dichloromethane, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate/hexane=l/10) to obtain

6-{4-[N,N-bis(4-methylphenyl)amino]phenyl}-4H"cyclopenta[ 2, l-b:

3,4-b']dithiophene-4-one-2-carbaldehyde (12) as a dark red solid (0.12 g, 73%).

iH NMR (600MHz, CDC1 3 ) δ: 9.76 (s, 1H), 7.58 (s, 1H), 7.36 (d, J = 6.6Hz, J = 1.8Hz, 4H), 7.16 (s, 1H), 7.11 (d, J = 8.4Hz, 4H), 7.03 (m, 4H), 6.99 (m, 2H), 2.33 (s, 6H).

This aldehyde (12) and cyanoacetic acid were treated as in Synthesis Example 1 to obtain

2-Cyano'3-{6"{4-[N,N-bis(4-methylphenyl)amino]phenyl}-4H-cyc lopenta[2,l- b: 3,4-b']dithiophene-4-one-2-yl}acrylic acid (NSQ3) (yield 76%).

NMR (600MHz, DMSO-de) δ: 8.15 (s, 1H), 7.65 (s, 1H), 7.51 (s, 2H), 7.37 (s,

2H), 7.14 (d, J = 7.8Hz, 4H), 6.96 (d, J = 7.8Hz, 4H), 6.85 (d, J = 7.8Hz, 2H),

2.27 (s, 6H).

(Synthesis Example 4)

As shown in the scheme of Chemical formula 44, by reacting the aldehyde intermediates (6), (10) or (12) of Synthesis Examples 1 to 3 with rhodanine-3-acetic acid in place of cyanoacetic acid as in Synthesis Examples 1 to 3, corresponding dyes,

2-{5-{{6-{5-{4-[N,N-bis(4-methylphenyl)amino]phenyl}thiophen -2-yl}-4H-cycl openta[2,l-b:3,4-b']dithiophene-4-one-2-yl}methylene}-4-oxo- 2-thioxothiazoli din-3-yOacetic ac id (NSQ4),

2-{5-{{6-{5'{4-[N,N-bis(4-methylphenyl)amino]phenyl}-3,4-eth ylenedioxythio phen-2-yl}'4H-cyclopenta[2,l-b:

3,4-b']dithiophene-4-one-2-yl}methylene}-4-oxo-2'thioxothiaz olidin-3-yl}aceti c acid (NSQ5), and

2-{5-{{6-{4-[N,N-bis(4-methylphenyl)amino]phenyl}-4H-cyclope nta[2,l-b:

3,4-b']dithiophene _ 4-one-2-yl}methylene}-4-oxo-2-thioxothiazolidin-3-yl}a ceti c acid (NSQ6) were obtained, respectively.

[Chemical formula 44]

NSQ4 (Yield 72%)

Ή NMR (600MHz, DMSO-d 6 )8: 8.05 (s, IH), 7.57 (s, IH), 7.48 (d, J = 8.4Hz, 2H), 7.37 (d, J = 4.2Hz, IH), 7.34 (d, J = 4.2Hz, IH), 7.29 (s, IH), 7.12 (d, J = 8.4Hz, 4H), 6.95 (d, J = 8.4Hz, 4H), 6.86 (d, J = 8.4Hz, 2H), 4.48 (s, 2H), 2.27 (s, 6H).

NSQ5 (Yield 76%)

iH NMR (600MHz, DMSO-d 6 ) 8: 8.05 (s, IH), 7.60 (s, IH), 7.51 (s, 2H), 7.13 (m, 5H), 6.92 (m, 6H), 4.48 (s, 2H), 4.43 (s, 2H), 4.35 (s, 2H), 2.27 (s, 6H) NSQ6 (Yield 78%)

Ή NMR (600MHz, DMSO-d 6 ) 8: 8.12 (s, IH), 7.66 (s, IH), 7.50 (s, 2H), 7.36 (s, 2H), 7.15 (d, J = 7.8Hz, 4H), 6.97 (d, J = 7.8Hz, 4H), 6.86 (d, J = 7.8Hz, 2H), 4.49 (s, 2H), 2.26 (s, 6H).

(Synthesis Example 5)

According to the following scheme,

2-cyano-3-(4-oxo-6-(4-(p-tolyl)-l,2,3,3a,4,8b-hexahydrocy clopenta[b]indol"7-y l)-4H-cyclopenta[2,l-b: 3,4-b']dithiophen-2-yl)acrylic acid (NSQ7) was obtained.

[Chemical formula 45]

NSQ7

o S nthe sis of 2 c ano - 3 - (4 - oxo - 6 - (4 - ( - tolyl) - l,2,3,3a,4,8b- hexahy drocy clo -penta[b]indol-7-yl)-4H-cyclopenta[2,l-b: 3,4-b']dithiophen-2-yl)acrylic acid (NSQ7) (see Chemical formula 45)

7-(4,4,5,5-Tetramethyl-l,3,2-dioxaborolan-2-yl)-4-(p-tolyl)- 1,2,3,3a, 4, 8b -hexahy droc clopentaDb] indole (0.19 g, 0.5 mmol), the aldehyde (2) (0.1 g, 0.35 mmol) and Pd (PPhs)4 (50 mg) were suspended in toluene (50 ml) and 2M K2CO3 aqueous solution (10 ml), and the resulting mixture was heated at reflux for 16 hours under the argon atmosphere. After completion of the reaction, water (120 ml) was added to the reaction solution, and the crude product was extracted with dichloromethane, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane/dichloromethane = 1/2) to obtain 4-oxo-6-(4-(p-tolyl)-l,2,3,3a,4,8b-hexahydrocyclopenta[b]ind ol-7-yl)-4H-cyclo penta [2,1-b: 3,4-b']dithiophene-2-carbaldehyde (13) as a dark red solid (0.12 g, 75%).

Ή NMR (600MHz, CDC1 3 ) δ= 9.73 (s, 1H), 7.55 (s, 1H), 7.27 (s, 1H), 7.22 (dd, J = 8.4Hz, J = 1.2Hz, 1H), 7.17 (s, 4H), 7.11 (s, 1H), 6.83 (dd, J = 8.4Hz, J = 4.2Hz, 2H), 4.82 (m, 1H), 3.84 (m, 1H), 2.35 (s, 3H), 2.07 (m, 1H), 1.92 (m, 2H), 1.88 (m, 1H), 1.78 (m, 1H), 1.59 (m, 1H).

The aldehyde (13) and cyanoacetic acid were treated as in Synthesis Example 1 to obtain 2-cyano-3-(4-oxo-6-(4-(p-tolyl)-l,2,3,3a,4,8b-hexahydro cyclopenta[b]indol-7-yl)-4H-cyclopenta[2,l-b: 3,4-b']dithiophen-2-yl)acrylic acid (NSQ7) (yield 71%).

1 H NMR (600MHz, DMSO-d6) & 8.35 (s, 1H), 7.80 (s, 1H), 7.45 (s, 1H), 7.37 (s, 1H), 7.33 (m, 1H), 7.19 (m, 4H), 6.81 (d, J = 2.4Hz, 1H), 4.89 (m, 1H), 3.83 (m, 1H), 2.28 (s, 3H), 2.03 (m, 1H), 1.81 (m, 3H), 1.64 (m, 1H), 1.38 (m, 1H). (Synthesis Example 6)

According to the following scheme, 2-((4-oxo-6-(4-(p-tolyl)-l,2,3,3a,4, 8b-hexahydrocyclopenta[b]indol-7-yl)-4H-cyclopenta[2,l-b:

3,4-b']dithiophen-2-yl)methylene)malonic acid (NSQ8) was obtained.

[Chemical formula 46]

NSQ8 oSynthesis of 2-((4-oxo-6-(4-(p-tolyl)-l,2,3,3a,4, 8b-hexahydrocyclo

■penta[b]indol-7-yl)-4H"cyclopenta[2,l-b: 3,4-b']dithiophen-2-yl)methylene) malonic acid (NSQ8) (see Chemical formula 46)

The aldehyde (13) and malonic acid were treated as in Synthesis Example 1 to obtain 2-((4-oxo-6-(4-(p-tolyl)-l, 2,3,3a, 4,8b"hexahydro

-cyclopenta[b]indol"7-yl)-4H-cyclopenta[2,l-b: 3,4-b']dithiophen-2-yl) methylene)malonic acid (NSQ8) (yield 65%).

NMR (600MHz, DMSO-d6) δ: 8.36 (s, 1H), 7.81 (s, 1H), 7.44 (s, 1H), 7.37 (s, 1H), 7.33 (m, 1H), 7.19 (m, 4H), 6.82 (d, J = 2.4Hz, 1H), 4.89 (m, 1H), 3.83 (m, 1H), 2.28 (s, 3H), 2.03 (m, 1H), 1.81 (m, 3H), 1.64 (m, 1H), 1.38 (m, 1H). (Synthesis Example 7)

According to the following scheme,

3-(6-(4-(N,N-bis(4-((2-ethylhexyl)oxy)

phenyl)amino)phenyl)-4-oxo-4H-cyclopenta[2,l-b:

3,4-b']dithiophen-2-yl)-2-cyanoacrylic acid (NSQ9) was obtained.

[Chemical formula 47]

oSynthesis of 3-(6-(4-(N,N-bis(4-((2-ethylhexyl)oxy)

phenyl)amino)phenyl)-4-oxo-4H-cyclopenta[2,l-b:

3,4-b']dithiophen-2-yl)"2-cyanoacrylic acid (NSQ9) (see Chemical formula 47)

4-Bromo-N,N-bis(4-((2-ethylhexyl)oxy)phenyl)aniline (3 g, 5.2 mmol) was dissolved in dry THF (100 ml), the solution was cooled to -78 °C under the argon atmosphere, and n-butyllithium (1.6M hexane solution) (3.9 ml) was added dropwise over 30 minutes. After completion of addition, the mixture was stirred at '78 °C for 2 hour, and isopropoxyboronic acid pinacol ester (1.16 g, 6.8 mmol) was added dropwise for 20 minutes. Thereafter, stirring was continued overnight, and a reaction temperature was returned to room temperature. Water (50ml) was added to the reaction solution, and the crude product was extracted with ethyl acetate, dried with magnesium sulfate, and concentrated under reduced pressure to obtain

4-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)"N,N-bis(4 -((2-ethylhexyl)oxy) phenyDaniline (14) as a white solid (2.9 g, 90%).

This aniline (14) (0.63 g, 1 mmol), the aldehyde (2) (0.3 g, 1 mmol) and Pd (PPhs)4 (50 mg) were suspended in toluene (50 ml) and 2M K2CO3 aqueous solution (10 ml), and the resulting mixture was heated at reflux for 16 hours under the argon atmosphere. After completion of the reaction, water (120 ml) was added to the reaction solution, and the crude product was extracted with dichloromethane, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate/hexane=l/10) to obtain

6-(4-(N,N"bis(4-((2-ethylhexyl)oxy)phenyl)amino)phenyl)-4 -oxo-4H-cyclopent a[2,l-b: 3,4-b'] dithiophene-2-carbaldehyde (15) as a dark red solid (0.55 g, 77%).

Ή NMR (600MHz, CDCI3) δ: 9.75 (s, 1H), 7.57 (s, 1H), 7.33 (d, J = 8.0Hz, 2H), 7.13 (s, 1H), 7.08 (d, J = 8.4Hz, 4H), 6.89 (d, J = 8.4Hz, 2H), 6.86 (d, J = 8.4Hz, 4H),3.83 (m, 4H), 1.71 (m, 2H), 1.51 (m, 8H), 1.33 (m, 8H), 0.93 (m, 12H).

The aldehyde (15) and cyanoacetic acid were treated as in Synthesis Example 1 to obtain

3-(6-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl)amino)phenyl)-4 -oxo-4H-cyclope nta[2,l-b: 3,4-b']dithiophen-2-yl)-2-cyanoacrylic acid (NSQ9) (yield 69%). Ή NMR (600MHz, DMSO-d6) 8: 8.24 (s, 1H), 7.57 (s, 1H), 7.34 (s, 2H), 7.37 15 (s, 1H), 7.06 (m, 4H), 6.89 (m, 6H), 3.83 (m, 4H), 1.73 (m, 2H), 1.48 (m, 8H), 1.43 (m, 8H), 0.94 (m, 12H).

(Synthesis Example 8)

According to the following scheme,

3-(5-(6-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl)amino)phe nyl)-4-oxo'4H-cycl openta[2,l-b ' - 3,4-b']dithiophen-2-yl)thiophen-2-yl)-2-cyanoacrylic acid (NSQ10) was obtained.

[Chemical formula 48]

NSQ10

o Synthesis of

3-(5-(6-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl)amino)phenyl )-4-oxo-4H-cycl openta[2,l-b: 3,4-b']dithiophen-2-yl)thiophen-2-yl)-2-cyanoacrylic acid

(NSQ10) (see Chemical formula 48)

The aniline (14) (0.63 g, 1 mmol), 2,6-dibromo-4H-cyclopenta[2,l-b"- 3,4-b']dithiophen-4-one (0.35 g, 1 mmol) and Pd (PPh 3 )4 (50 mg) were suspended in toluene (50 ml) and 2M K2CO3 aqueous solution (10 ml), and the resulting mixture was heated at reflux for 16 hours under the argon atmosphere. After completion of the reaction, water (120 ml) was added to the reaction solution, and the crude product was extracted with

dichlorome thane, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column

chromatography (ethyl acetate/hexane = 1/20) to obtain

2-bromo-6-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl) amino)

phenyl)-6-bromo-4H-cyclopenta[2,l-b: 3,4-b']dithiophen-4-one (16) as a dark red solid (0.5 g, 65%).

NMR (600MHz, CDCI3) δ: 7.47 (s, 1H), 7.31 (d, J = 8.0Hz, 2H), 7.13 (s, 1H), 7.08 (d, J = 8.4Hz, 4H), 6.89 (d, J = 8.4Hz, 2H), 6.86 (d, J = 8.4Hz, 4H),3.83 (m, 4H), 1.71 (m, 2H), 1.51 (m, 8H), 1.33 (m, 8H), 0.93 (m, 12H).

The aniline (16) (0.39 g, 0.5 mmol), 5-formylthiophen-2-ylboronic acid (0.156 g, 1 mmol) and Pd(PPh3) (10 mg) were dissolved in toluene (30 ml) and 2M K2CO3 aqueous solution (5 ml), and the solution was heated at reflux for 24 hours under the argon atmosphere. To the reaction solution was added water (50 ml), and the crude product was extracted with

dichloromethane, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column

chromatography (hexane/dichloromethane = 1/2) to obtain 5-(6-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl)

amino)phenyl)-4-oxo-4H-cyclopenta[2,l-b:

3,4-b']dithiophen-2-yl)thiophene-2-carbaldehyde (17) (0.28 g, 71%).

iH NMR (600MHz, CDC1 3 ) 6: 9.83 (s, 1H), 7.64 (s, 1H), 7.55 (m, 2H),

7.47-7.29 (m, 3H), 7.13 (s, 2H), 7.08 (d, J = 8.4Hz, 4H), 6.86 (d, J = 8.4Hz, 4H), 3.83 (m, 4H), 1.73 (m, 2H), 1.44 (m, 8H), 1.32 (m, 8H), 0.94 (m, 12H).

The aldehyde (17) (0.2 g, 0.25 mmol) and cyanoacetic acid (68 mg, 0.8 mmol) were dissolved in chloroform (10 ml), piperidine (0.14 g, 1.6 mmol) was added, and the resulting mixture was heated at reflux for 12 hours under the argon atmosphere. To the reaction solution was added 2N HC1 (10 ml), water (80 ml) was added, and the crude product was extracted with chloroform, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (methanol/chloroform = 1/10) to obtain

3-(5-(6-(4-(N,N-bis(4-((2-ethylhexyl)oxy)

phenyl)amino)phenyl)-4-oxo-4H-cyclopenta[2,l-b:

3,4-b']dithiophen-2-yl)thiophen-2-yl)-2-cyanoacrylic acid (NSQIO) as a dark red solid (0.16 g, 73%).

Ή NMR (600MHz, CDC1 3 ) δ: 8.21 (s, 1H), 7.58 (s, 1H), 7.29-7.23 (m, 2H), 7.13 (s, 1H), 7.02 (m, 5H), 6.85 (m, 6H), 4.35 (s, 4H), 3.84 (d, J = 6 Hz, 4H), 1.71 (m, 2H), 1.48 (m, 8H), 1.32 (m, 8H), 0.92 (m, 12H).

Light absorption spectra of synthesized dyes, NSQ1, NSQ2, NSQ3, NSQ4, NSQ5, NSQ6, NSQ7, NSQ8, NSQ9 and NSQ10 are shown in Fig. 1 and Fig. 2. As is seen from two figures, a maximum absorption wavelength shifted to a long wavelength side in all synthesized dyes, and a broad absorption band could be obtained in a visible light region. Particularly, in NSQ2, 4, 5, 7, 9 and 10, an absorption band is recognized also in a near infrared region.

Example 2

o Manufacturing of organic dye-sensitized solar cell

A metal oxide semiconductor electrode was made using a

commercially available titanium oxide paste (manufactured by Solaronix). Specifically, a titanium oxide paste was coated on a tin oxide -coated electrically conductive glass by a screen printing method, and this was fired at 500°C for 1 hour in the air, thereby, a titanium oxide semiconductor electrode having a film thickness of 5 to 25 micron was obtained. This electrode was soaked in a 0.3 mM solution of the organic dye of the present invention (solvent was t-butanol and acetonitrile 1 1 mixed solvent), and this was allowed to stand at room temperature for 10 to 30 hours, thereby, an organic dye-adsorbed titanium oxide semiconductor electrode was obtained.

A titanium oxide semiconductor electrode (film thickness 15pm) on which a dye being the 4H-cyclopentadithiophene-4-one derivative of the present invention had been adsorbed, and a counter electrode of a

platinum-sputtered electrically conductive glass were piled by holding a thermally pressed spacer therebetween, this was closely sealed to make a cell, and a mixed solution of l,2-dimethyl-3-propylimidazolium iodide (0.6M), lithium iodide (0.1M), iodine (0.05M), and t-butylpyridine (0.5 M) in acetonitrile which is an electrolyte was injected into cell gaps.

oAssessment of photoelectric conversion property of manufactured solar cell Photoelectric conversion property of the manufactured cell was measured using a xenon lamp as a light source, and a solar simulator (AMI.5, 100 mWcm '2 ) consisting of an AM filter, and photocurrent voltage property was measured using s source meter.

From results of such the measurement, performance of the

manufactured electric conversion element was assessed. Specifically, current -voltage property was measured at room temperature, a short-circuit current (Jsc), an open-circuit voltage (Voc), and a fill factor (FF) were obtained, and a photocurrent conversion efficiency ( ) was obtained from them. Herein, the photo-current conversion efficiency η (%) was calculated by the following equation,

η = 100 x(JscxVocxFF)/P

In the above equation, P denotes an incident light intensity (mW/cm 2 ), Voc denotes an open-circuit voltage (V), Jsc denotes a short-circuit current density (mA/cm 2 ), and FF denotes a fill factor.

Results of photocurrent conversion element assessment of the dye-sensitized solar cell using dyes, NSQ1, NSQ2, NSQ3, NSQ4, NSQ5, NSQ6, NSQ7, NSQ8, NSQ9 and NSQ10 which are the

4H-cyclopentadithiophene-4-one-based organic dyes of the present invention synthesized in Example 1 are shown in Table 1.

[Table l]

Example 3

(Synthesis Example 9)

According to the following scheme,

2-cyano-3-(4-(7-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl)amin o)phenyl)-9-oxo -9H- fluoren-2-yl)phenyl)acrylic acid (HIQFl) was obtained.

[Chemical formula 49]

HIQF1 o Synthesis of

2-cyano-3-(4-(7-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl)amin o)phenyl)-9-oxo -9H- fluoren-2-yDphenyl)acrylic acid (HIQFl)

4-Bromo-N,N-bis(4-((2-ethylhexyl)oxy) phenyl) aniline (3 g, 5.2 mmol) was dissolved in dry THF (100 ml), the solution was cooled to -78°C under the argon atmosphere, and n-butyllithium (1.6M hexane solution) (3.9 ml) was added dropwise over 30 minutes. After completion of addition, the mixture was stirred at -78°C for 2 hour, and isopropoxyboronic acid pinacol ester (1.16 g, 6.8 mmol) was added dropwise for 20 minutes. Thereafter, stirring was continued overnight, and a reaction temperature was returned to room temperature. Water (50ml) was added to the reaction solution, and the crude product was extracted with ethyl acetate, dried with magnesium sulfate, and concentrated under reduced pressure to obtain

4-(4,4,5,5-tetramethyl-l,3,2

dioxaborolan-2-yl)-N,N-bis(4-((2-ethylhexyl)oxy)phenyl )aniline (l) as a white solid (2.9 g, 90%).

The aniline (l) (0.63 g, 1 mmol), 2,7-dibromo -9H-fluoren-9 one (0.34 g, 1 mmol) and Pd (PPhs)4 (50 mg) were suspended in toluene (50 ml) and 2M K2CO3 aqueous solution (10 ml), and the resulting mixture was heated at reflux for 16 hours under the argon atmosphere. After completion of the reaction, water (120 ml) was added to the reaction solution, and the crude product was extracted with dichloromethane, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane/dichloromethane = 1/2) to obtain 2-bromo-7-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl)amino)phen yl)-9-oxo- 9H-fluorene (2) as a red solid (0.68 g, 89.6%).

Ή NMR (600MHz, CDCI3) δ: 7.85 (s, 1H), 7.76 (d, J = 1.8Hz, 1H), 7.68 (d, J = 7.2Hz, 1H), 7.61 (dd, J = 7.8Hz, J = 1.8Hz, 1H), 7.52 (d, J = 7.8Hz, 1H), 7.41 (m, 3H), 7.08 (s, 4H), 6.97 (s, 2H), 6.85 (d, J = 8.4Hz, 4H), 3.82 (s, 4H), 1.72 (m, 2H), 1.49 (m, 8H), 1.32 (m, 8H), 0.92 (m, 12H).

The fluorenone (2) (0.38 g, 0.5 mmol), p-formylphenylboronic acid (0.3 g, 1 mmol) and Pd(PPli3)4 (10 mg) were dissolved in toluene (30 ml) and 2M K2CO3 aqueous solution (5 ml), and the solution was heated at reflux for 24 hours under the argon atmosphere. To the reaction solution was added water (50 ml), and the crude product was extracted with dichloromethane, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography

(hexane/dichlorome thane = 1/2) to obtain

4-(7-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl)amino)phenyl)-9 -oxo-9H- fluoren-2-yl) phenylcarbaldehyde (3) (0.28 g, 72.7%).

Ή NMR (600MHz, CDC1 3 ) δ: 10.06 (s, 1H), 7.98 (d, J = 8.4 Hz, 2H), 7.93 (d, J = 1.8 Hz, 1H), 7.89 (d, J = 1.8 Hz, 1H), 7.79 (s, 1H), 7.77 (m, 2H), 7.70 (dd, J = 7.8 Hz, J = 1.8 Hz, 1H), 7.61 (d, J = 7.8 Hz, 1H), 7.57 (d, J = 7.8 Hz, 1H), 7.09 (dd, J = 6.6 Hz, J = 1.8 Hz, 4H), 6.99 (d, J = 7.2 Hz, 2H), 6.86 (dd, J = 7.2 Hz, J = 1.8 Hz, 4H), 3.83 (m, 4H), 1.73 (m, 2H), 1.44 (m, 8H), 1.32 (m, 8H), 0.94 (m, 12H).

The aldehyde (3) (0.2 g, 0.25 mmol) and cyanoacetic acid (68 mg, 0.8 mmol) were dissolved in chloroform (10 ml), piperidine (0.14 g, 1.6 mmol) was added, and the resulting mixture was heated at reflux for 12 hours under the argon atmosphere. To the reaction solution was added 2N HC1 (10 ml), water (80 ml) was added, and the crude product was extracted with chloroform, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (methanol/chloroform = l/lO) to obtain

2-cyano-3-(4-(7-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl)amin o)phenyl)-9-oxo -9H- fluoren-2-yl)phenyl)acrylic acid (HIQFl) as a red solid (0.11 g, 56.4%). Ή NMR (600MHz, DMSO-de) δ: 8.29 (s, 1H), 8.11 (d, J = 8.4 Hz, 2H), 8.04 (dd, J = 8.4 Hz, J = 1.8 Hz, lH), 7.98 (s, lH), 7.96 (m, 2H), 7.90 (s, lH), 7.85 (m, 2H), 7.79 (s, 1H), 7.59 (d, J = 9 Hz, 2H), 7.03 (m, 4H), 6.92 (m, 4H), 6.81 (d, J = 8.4 Hz, 2H), 3.83 (d, J = 6 Hz, 4H), 1.77 (m, 2H), 1.41 (m, 8H), 1.28 (m, 8H), 0.88 (m, 12H).

(Synthesis Example 10)

According to the following scheme,

2-cyano-3-(5-(7-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl)a mino)phenyl)-9-oxo -9H-fluoren-2-yl)thiophen-2-yl)acrylic acid (HIQF2) was obtained.

[Chemical formula 50]

oSynthesis of

2-cyano-3-(5-(7-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl)amin o)phenyl)-9-oxo 9H-fluoren-2-yl)thiophen-2-yl)acrylic acid (HIQF2)

The fluorenone (2) (0.38 g, 0.5 mmol) (see Chemical formula 49),

5-formylthiophen-2-ylboronic acid (0.156 g, 1 mmol) and Pd(PPhs)4 (10 mg) were dissolved in toluene (30 ml) and 2M K2CO3 aqueous solution(5 ml), and the solution was heated at reflux for 24 hours under the argon atmosphere. To the reaction solution was added water (50 ml), and the crude product was extracted with dichloromethane, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane/dichloromethane = 1/2) to obtain

5-(7-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl)amino)phenyl )-9-oxo'9H-fluoren -2-yl)thiophene-2-carbaldehyde (4) (0.3 g, 75%).

1 H NMR (600MHz, CDC1 3 ) δ: 9.89 (s, 1H), 7.92 (s, 1H), 7.86 (s, 1H), 7.75 (m, 2H), 7.67 (m, 1H), 7.54 (d, J = 7.8 Hz, 1H), 7.41 (m, 4H), 7.09 (d, J = 8.4 Hz, 4H), 6.98 (d, J = 8.4 Hz, 2H), 6.86 (d, J = 8.4 Hz, 4H), 3.83 (m, 4H), 1.73 (m, 2H), 1.44 (m, 8H), 1.32 (m, 8H), 0.94 (m, 12H).

The aldehyde (4) (0.2 g, 0.25 mmol) and cyanoacetic acid (68 mg, 0.8 mmol) were dissolved in chloroform (10 ml), piperidine (0.14 g, 1.6 mmol) was added, and the resulting mixture was heated at reflux for 12 hours under the argon atmosphere. To the reaction solution was added 2N HC1 (10 ml), water (80 ml) was added, and the crude product was extracted with chloroform, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (methanol/chloroform = l/lO) to obtain

2-cyano-3-(5-(7-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl)amin o)phenyl)-9-oxo -9H-fluoren-2-ylHhiophen-2-yl)acrylic acid (HIQF2) as a dark red solid (0.13 g, 79.2%).

Ή NMR (600MHz, DMSO-d 6 ) δ: 8.43 (s, 1H), 8.01 (d, J = 9Hz, 1H), 7.98 (d, J = 9Hz, 1H), 7.95 (s, 1H), 7.92 (d, J = 3.6Hz, 1H), 7.91 (d, J = 7.8Hz, 1H), 7.86 (s, 2H), 7.82 (s, 1H), 7.61 (d, J = 9 Hz, 2H), 7.06 (d, J = 8.4Hz, 4H), 6.94 (d, J = 9Hz, 4H), 6.82 (d, J = 9Hz, 2H), 3.84 (d, J = 6 Hz, 4H), 1.67 (m, 2H), 1.43 (m, 8H), 1.29 (m, 8H), 0.88 (m, 12H). (Synthesis Example 11)

According to the following scheme,

2-cyano-3-(5-(7-(5-(4-(N,N-bis(4-((2-ethylhexyl)oxy)pheny l)amino)phenyl)-3,4 (ethylenedioxy)thiophen-2-yl)-9-oxo-9H-fluoren-2-yl)th iophen-2-yl)acrylic acid (HIQF3) was obtained.

[Chemical formula 51]

HIQF3 oSynthesis of

2 yano-3-(5-(7-(5-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl)amin o)phenyl)-3,4

-(ethylenedioxy)thiophen-2-yl)-9-oxo-9H-fluoren-2-yl)thio ^

acid (HIQF3)

4-Bromo-N,N-bis(4-((2-ethylhexyl)oxy)phenyl)aniline (1 g, 1.7 mmol), 2-(tributylstannyl)-3,4-(ethylenedioxy)thiophene (0.86 g, 2 mmol) and

Pd(PPb.3)4 (20 mg) were suspended in dry toluene (20 ml), and the suspension was heated at reflux for 24 hours under the argon atmosphere. After completion of the reaction, water (30 ml) was added to the reaction solution, and the crude product was extracted with dichlorome thane, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (dichloromethane/hexane = 1/20) to obtain

4-(3,4-(ethylenedioxy)thiophen-2-yl)-N,N-bis(4-((2-ethylhexy l)oxy)phenyl)ani line (5) as a yellow oily solid (0.8 g, 72%).

NMR (600 MHz, DMSO-d6) 8: 7.45 (d, J = 8.8 Hz, 2H), 6.99 (d, J = 8.8 Hz, 4H), 6.91 (d, J = 8.8 Hz, 4H), 6.78 (d, J = 8.8 Hz, 2H), 6.48 (s, 1H), 4.25 (m, 2H), 4.24 (m, 2H), 3.82 (t, J=6.0 Hz, 4H), 1.66 (m, 2H), 1.40 (m, 8H), 1.31 (m, 8H), 0.89 (m, 12H).

The aniline (5) (0.64 g, 1 mmol) was dissolved in dry THF (20 ml), the solution was cooled to -78°C under the argon atmosphere, and n-butyllithium (1.6M hexane solution) (0.68 ml) was added dropwise over 15 minutes.

After addition, the mixture was stirred at -78°C for 1 hour, and

tributylstannyl chloride (0.39 g, 1.2 mmol) was added dropwise over 10 minutes. Thereafter, stirring was continued overnight, and a temperature was returned to room temperature. To the reaction solution was added water (10 ml), and the crude product was extracted with ethyl acetate, dried with magnesium sulfate and concentrated under reduced pressure to obtain 4-(5-tributylstannyl-3,4-(ethylenedioxy)thiophen-2-yl)-N,N-b is(4-((2-ethylhe xyl)oxy)phenyl)aniline (6) as a colorless oil (0.65 g, 70%).

Ή NMR (600MHz, CDCls) δ'· 7.42 (d, J = 6.6Hz, 2H), 7.08 (d, J = 8.4Hz, 4H), 6.99 (m, 7H), 6.92 (d, J = 3.6Hz, 1H), 6.48 (s, 1H), 4.26 (m, 2H), 4.24 (m, 2H), 3.83 (d, J = 6 Hz, 4H), 2.32 (m, 6H), 1.77 (m, 2H), 1.62-1.48 (m, 6H), 1.41 (m, 8H), 1.38-1.22 (m, 6H), 1.28 (m, 8H), 1.10 (t, 9H), 0.89 (q, 6H), 0.86 (m, 12H).

The aniline (6) (0.6 g, 0.65 mmol), 2,7-dibromo-9-oxy9H-fluorene (0.34 g, 1 mmol) and Pd (PPh3) 4 (50 mg) were dissolved in dry toluene (20 ml), and the solution was heated at reflux for 24 hours under the argon

atmosphere. To the reaction solution was added water (50 ml), and the crude product was extracted with dichloromethane, dried with magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate/hexane = l/lO) to obtain 2-bromo-7-(5-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl)amino)p henyl)-3,4-(eth ylenedioxy) thiophen-2-yl)-9-oxo-9H-fluorene (7) (0.48 g, 82%).

NMR (600MHz, CDCls) δ= 8.07 (d, J = 1.8 Hz, 1H), 7.80 (dd, J = 8.4 Hz, J = 1.8 Hz, 1H), 7.75 (d, J = 1.8 Hz, 1H), 7.58 (dd, J = 7.8 Hz, J = 1.8 Hz, 1H), 7.53 (d, J = 8 Hz, 2H), 7.45 (d, J = 7.8 Hz, 1H), 7.35 (d, J = 7.8 Hz, 1H), 7.07 (dd, J = 12 Hz, J = 3 Hz, 4H), 6.93 (d, J = 8.4 Hz, 2H), 6.84 (dd, J = 12 Hz, J = 3 Hz, 4H), 4.38 (d, J = 4.2 Hz, 2H), 4.33 (d, J = 4.2 Hz, 2H), 3.82 (m, 4H), 1.71 (m, 2H), 1.49 (m, 8H), 1.32 (m, 8H), 0.92 (m, 12H).

The fluorenone (7) (0.45 g, 0.5 mmol), 5-formylthiophen-2-ylboronic acid (0.156 g, 1 mmol) and Pd(PPh 3 ) 4 (10 mg) were dissolved in toluene (30 ml) and 2M K2CO3 aqueous solution (5 ml), and the solution was heated at reflux for 24 hours under the argon atmosphere. To the reaction solution was added water (50 ml), and the crude product was extracted with dichloromethane, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column

chromatography (hexane/dichloromethane = 1/2) to obtain

5-(7-(5-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl)amino)phe ny)-3,4-(ehylenedi oxy)thiophen-2-yl)-9-oxo-9H-fluoren-2-yl)thiophene-2-carbald ehyde (8) (0.39 g, 84%).

Ή NMR (600MHz, CDC1 3 ) δ: 9.90 (s, 1H), 8.12 (s, 1H), 7.95 (s, 1H), 7.84 (d, J = 7.8 Hz, 1H), 7.78 (d, J = 7.8 Hz, 1H), 7.76 (m, 1H), 7.55 (m, 4H), 7.47 (m, 4H), 7.06 (d, J = 8.4 Hz, 4H), 6.93 (d, J = 8.4 Hz, 2H), 6.83 (d, J = 8.4 Hz, 4H), 4.40 (d, J = 4.2 Hz, 2H), 4.35 (d, J = 4.2 Hz, 2H), 3.82 (m, 4H), 1.71 (m, 2H), 1.49 (m, 8H), 1.32 (m, 8H), 0.92 (m, 12H).

The aldehyde (8) and cyanoacetic acid were treated as in Synthesis Example 9 to obtain

2-cyano-3-(5-(7-(5-(4-(N,N-bis(4-((2-ethylhexyl)oxy)phenyl)a mino)phenyl)-3,4 -(ethylenedioxy)thiophen-2-yl)-9-oxo-9H-fluoren-2-yl)thiophe n-2-yl)acrylic acid (HIQF3) (yield 79%).

Ή NMR (600MHz, DMSO-d 6 ) 8: 8.30 (s, 1H), 7.94 (d, J = 7.8 Hz, 1H), 7.90 (s, 1H), 7.88 (m, 3H), 7.80 (m, 3H), 7.50 (s, 1H), 7.48 (s, 1H), 7.01 (d, J = 8 Hz, 4H), 6.91 (d, J = 8 Hz, 4H), 6.78 (d, J = 8 Hz, 2H), 4.45 (s, 2H), 4.37 (s, 2H), 3.83 (d, J = 6 Hz, 4H), 1.68 (m, 2H), 1.45 (m, 8H), 1.31 (m, 8H), 0.91 (m, 12H). (Synthesis Example 12) According to the following scheme,

2-cyano-3-(5-(7-(4-(N,N-di-p-tolylamino)phenyl)-9-oxo-9H- fluoren-2-yl)thioph en-2-yl)acrylic acid (HIQF4) was obtained.

[Chemical formula 52]

HIQF4

o Synthesis of

2-cyano-3"(5-(7-(4-(N,N-di-p-tolylamino)phenyl)-9-oxo-9H-flu oren-2-yl)thioph en-2-yDacrylic acid (HIQF4)

4-(N,N-Di-p-tolylamino)phenylboronic acid pinacol ester (0.4 g, 1 mmol), 2,7-dibromo-9-oxo-9H-fluorene (0.34 g, 1 mmol) and Pd (PPh 3 )4 (50 mg) were suspended in toluene (50 ml) and 2M K2CO3 aqueous solution (10 ml), and the resulting mixture was heated at reflux for 16 hours under the argon atmosphere. After completion of the reaction, water (120 ml) was added to the reaction solution, and the crude product was extracted with dichloromethane, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column

chromatography (hexane/dichloromethane = 1/2) to obtain

2-bromo-7-(4-(N,N-di-p-tolylamino)phenyl)-9'Oxo-9H-fluore ne (9) as a red solid (0.36 g, 68%).

Ή NMR (600MHz, CDCI3) 6: 7.86 (d, J = 1.8Hz, 1H), 7.77 (d, J = 1.8Hz, 1H), 7.69 (dd, J = 7.8Hz, J = 1.8Hz, 1H), 7.61 (d, J = 1.8Hz, 1H), 7.69 (dd, J = 7.8Hz, J =1.8 Hz, 1H), 7.53 (d, J = 7.8Hz, 1H), 7.45 (d, J = 7.8Hz, 2H), 7.41 (d, J =7.8 Hz, 1H), 7.07 (m, 5H), 7.06 (s, 1H), 7.04 (s, 1H), 7.03 (s, 1H), 2.33 (s, 6H).

The fluorenone (9) (0.27 g, 0.5 mmol), 5-formylthiophen-2-ylboronic acid (0.156 g, 1 mmol) and Pd(PPhs)4 (10 mg) were dissolved in toluene (30 ml) and 2M K2CO3 aqueous solution (5 ml), and the solution was heated at reflux for 24 hours under the argon atmosphere. To the reaction solution was added water (50 ml), and the crude product was extracted with dichloromethane, dried with magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column

chromatography (hexane/dichloromethane = 1/2) to obtain

5-(7-(4-(N,N-di-p-tolylamino)phenyl)-9"oxo-9H-fluoren-2-y l)thiophene-2-carb aldehyde (10) (0.48 g, 85%).

NMR (600MHz, CDC1 3 ) 8= 9.91 (s, 1H), 7.96 (d, J = 1.8Hz, 1H), 7.91 (d, J = 1.8Hz, 1H), 7.80 (dd, J = 7.8Hz, J = 1.8Hz, 1H), 7.77 (d, J = 3.6Hz, 1H), 7.73 (dd, J = 7.8Hz, J =1.8 Hz, 1H), 7.59 (d, J = 7.8Hz, J = 1.8Hz, 2H), 7.45 (d, J = 7.8Hz, 2H), 7.41 (s, 1H), 7.07 (m, 5H), 7.05 (m, 5H), 2.33 (s, 6H).

The aldehyde (10) and cyanoacetic acid were treated as in Synthesis Example 9 to obtain

2-cyano-3-(5-(7-(4-(N,N-di-p-tolylamino)phenyl)-9-oxo-9H-flu oren-2-yl)thioph en-2-yDacrylic acid (HIQF4) (yield 75%).

NMR (600MHz, DMSO-d 6 ) δ: 8.37 (s, 1H), 8.32 (s, 1H), 8.01 (d, J = 7.8Hz, 1H), 7.95 (m, 2H), 7.89 (m, 4H), 7.85 (s, 1H), 7.66 (d, J = 8.4Hz, 2 H), 7.16 (d, J = 8.4Hz, 4H), 6.98 (d, J = 8.4Hz, 4H), 6.95 (d, J = 8.4Hz, 2H), 2.26 (s, 6H). (Synthesis Example 13)

As shown in the scheme of Chemical formula 53, by reacting the aldehyde intermediates (10) of Synthesis Example 4 with rhodanine-3-acetic acid in place of cyanoacetic acid as in Synthesis Example 9,

2-(5-(5-(7-(4-(N,N-di-p-tolylamino)phenyl)-9-oxo-9H-fluor en-2-yl)thiophen'2- yl)methylene-4-oxo-2-thioxothiazolidin-3-yl)acetic acid (HIQF5) was obtained.

[Chemical formula 53]

HIQF5

HIQF5 (Yield 73%)

NMR (600MHz, DMSO-d 6 )8: 8.32 (s, 1H), 8.15 (s, 1H), 8.05 (d, J = 7.8Hz, 1H), 8.02 (s, 1H), 7.96 (d, J = 4.2Hz, 1H), 7.84 (m, 3H), 7.81 (m, 2H), 7.66 (d, J = 9Hz, 2H), 7.16 (d, J = 8.4Hz, 4H), 7.00 (d, J = 8.4Hz, 4H), 6.94 (d, J = 8.4Hz, 2H), 4.64 (s, 2H), 2.28 (s, 6H).

Light absorption spectra of synthesized dyes, HIQF1, HIQF2, HIQF3, HIQF4 and HIQF5 are shown in Fig. 3. As is seen from Fig. 3, a maximum absorption wavelength shifted to a long wavelength side in all synthesized dyes, and a broad absorption band could be obtained in a visible light region. Example 4

o Manufacturing of organic dye-sensitized solar cell

A metal oxide semiconductor electrode was made using a

commercially available titanium oxide paste (manufactured by Solaronix). Specifically, a titanium oxide paste was coated on a tin oxide-coated electrically conductive glass by a screen printing method, and this was fired at 500°C for 1 hour in the air, thereby, a titanium oxide semiconductor electrode having a film thickness of 5 to 25 micron was obtained. This electrode was soaked in a 0.3 mM solution of the organic dye of the present invention (solvent was t-butanol and acetonitrile 1:1 mixed solvent), and this was allowed to stand at room temperature for 10 to 30 hours, thereby, an organic dye-adsorbed titanium oxide semiconductor electrode was obtained.

A titanium oxide semiconductor electrode (film thickness 15μηι) on which a dye being the fluorenone derivative of the present invention had been adsorbed, and a counter electrode of a platinum-sputtered electrically conductive glass were piled by holding a thermally pressed spacer

therebetween, this was closely sealed to make a cell, and a mixed solution of l,2-dimethyl-3-propylimidazolium iodide (0.6M), lithium iodide (0.1M), iodine (0.05M), and t-butylpyridine (0.5 M) in acetonitrile, which is an electrolyte, was injected into cell gaps. oAssessment of photoelectric conversion property of manufactured solar cell

Photoelectric conversion property of the manufactured cell was measured using a xenon lamp as a light source, and a solar simulator (AMI.5, 100 mWcm '2 ) consisting of an AM filter, and photocurrent voltage property was measured using s source meter.

From results of such the measurement, performance of the

manufactured electric conversion element was assessed. Specifically, current -voltage property was measured at room temperature, a short-circuit current (Jsc), an open-circuit voltage (Voc), and a fill factor (FF) were obtained, and a photocurrent conversion efficiency (n) was obtained from them. Herein, the photo-current conversion efficiency η (%) was calculated by the following equation,

η = 100 x(JscxVocxFF)/P

In the above equation, P denotes an incident light intensity (mW/cm 2 ), Voc denotes an open-circuit voltage (V), Jsc denotes a short-circuit current density (mA/cm 2 ), and FF denotes a fill factor.

Results of photocurrent conversion element assessment of the dye-sensitized solar cell using dyes, HIQF1, HIQF2, HIQF3, HIQF4, and HIQF5 which are the fluorenone -based organic dyes of the present invention synthesized in Example 3 are shown in Table 2. [Table 2]

Industrial Applicability

As explained in detail above, the present invention is expected to greatly contribute to solar light electric generation industry whose importance has particularly increased in recent years.