JP2016147939A - Nitrophenol compound and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an azo bond-free red pigment free from the risk that toxic organic amines are discharged into the environment by decomposition or the like.SOLUTION: Provided is a nitrophenol compound represented by formula (1)(R,R,Rand Rare respectively independently H or a nitro group; where all of R, R, Rand Rcannot be H, simultaneously; Rdenotes H or a 1 to 12C alkyloxy group, independently; Y denotes a chalcogen atom or a nitrogen atom may be substituted with a 1 to 6C alkyl group; and n denotes the integer of 1 to 5).SELECTED DRAWING: None

Description

  The present invention relates to nitrophenol compounds useful as red pigments, and methods for producing these nitrophenol compounds.

  Dye compositions containing red pigments are widely used in various paints, water-based or oil-based inks, inkjet inks, display element color filters, and the like. As such a red pigment, for example, CI Pigment Red (Patent Documents 1 and 2) and the like are known, and all of them are characterized by containing an azo bond as a chromophore exhibiting a red color. On the other hand, when a dye containing an azo bond is released to the environment, the azo bond undergoes reductive degradation by microorganisms to produce organic amines. However, there is a concern that the organic amines may have mutagenic properties. There is. For this reason, it is desired to use an alternative for a dye containing an azo bond.

US Pat. No. 4,224,221 JP 61-181864 A

  The object is to provide a red pigment that does not contain an azo bond and that does not release toxic organic amines into the environment by decomposition or the like.

  As a result of intensive studies to solve the above problems, the present inventors have found that the following general formula (1)

（式中、Ｒ^２ａ、Ｒ^２ｂ、Ｒ^２ｃ及びＲ^２ｄは、各々独立に、水素原子又はニトロ基を表す。但し、Ｒ^２ａ、Ｒ^２ｂ、Ｒ^２ｃ及びＲ^２ｄは、全てが同時に水素原子とは成り得ない。Ｒ^３は、各々独立に、水素原子又は炭素数１〜１２のアルキルオキシ基を表す。Ｙはカルコゲン原子又は炭素数１〜６のアルキル基で置換されていてもよいニクトゲン原子を表す。ｎは１〜５の整数を表す。）
で表されるニトロフェノール化合物（以下、「ニトロフェノール化合物（１）」とも称する）が、一般的な発色団であるアゾ結合によることなく、赤色の呈色に有効であることを見出し、本発明を完成するに至った。

(In the formula, R ^2a , R ^2b , R ^2c and R ^2d each independently represent a hydrogen atom or a nitro group, provided that R ^2a , R ^2b , R ^2c and R ^2d are all hydrogen atoms at the same time. R ³ each independently represents a hydrogen atom or an alkyloxy group having 1 to 12 carbon atoms, and Y represents a nicotine atom which may be substituted with a chalcogen atom or an alkyl group having 1 to 6 carbon atoms. N represents an integer of 1 to 5.)
The nitrophenol compound represented by the following (hereinafter also referred to as “nitrophenol compound (1)”) is found to be effective for coloration of red without being caused by an azo bond which is a general chromophore, and the present invention. It came to complete.

  That is, this invention relates to said nitrophenol compound and its manufacturing method.

  Since the nitrophenol compound of the present invention does not have an azo bond, it is useful as a red pigment that does not release toxic organic amines due to microbial degradation.

  The present invention is described in further detail below.

The definitions of R ³ , Y and n in the nitrophenol compound (1) of the present invention will be described.

R < ³ > represents a hydrogen atom or a C1-C12 alkyloxy group each independently.

The alkyloxy group having 1 to 12 carbon atoms represented by R ³ may be any of a linear, branched or cyclic alkyloxy group, and is not particularly limited, but specifically includes a methoxy group and cyclohexyl. Methyloxy group, ethoxy group, 2-cyclopentylethyloxy group, propyloxy group, 1-methylpropyloxy group, 1-ethylpropyloxy group, 1,1-diethylpropyloxy group, 2,2-dimethylpropyloxy group, 2,2-dimethyl-1-tert-butylpropyloxy group, 3-cyclopropylpropyloxy group, isopropoxy group, cyclopropyloxy group, butoxy group, 1-methylbutyloxy group, 2-methylbutyloxy group, 3 -Methylbutyloxy group, 2-butoxy group, cyclobutyloxy group, pentyloxy group, 1-methyl Pentyloxy group, 2-methylpentyloxy group, 3-ethylpentyloxy group, 2,4-dimethylpentyloxy group, cyclopentyloxy group, 2,5-dimethylcyclopentyloxy group, 1,2,3,4,5- Pentamethylcyclopentyloxy group, 3-ethylcyclopentyloxy group, 3-butylcyclopentyloxy group, hexyloxy group, 1-methylhexyloxy group, 2-methylhexyloxy group, 3-methylhexyloxy group, 3,3-dimethyl Hexyloxy group, 4-ethylhexyloxy group, cyclohexyloxy group, 4-ethylcyclohexyloxy group, 4,4-dimethylcyclohexyloxy group, 2,2,6,6-tetramethylcyclohexyloxy group, heptyloxy group, 1- Methylheptyloxy group, 2-methyl Ptyloxy group, 3-methylheptyloxy group, bicyclo [2.2.1] heptyloxy group, octyloxy group, cyclooctyloxy group, bicyclo [2.2.2] octyloxy group, nonanyloxy group, decyloxy group, dodecyl An oxy group etc. can be illustrated.

R ³ is also preferably a hydrogen atom.

R ³ is preferably a hydrogen atom, a methoxy group, an ethoxy group, or a hexyloxy group, more preferably a hydrogen atom, in terms of a large extinction coefficient.

  Y represents a chalcogen atom or a nictogen atom which may be substituted with an alkyl group having 1 to 6 carbon atoms.

  Although it does not specifically limit as a chalcogen atom represented by Y, For example, an oxygen atom, a sulfur atom, a selenium atom, a tellurium atom etc. can be illustrated.

  The nictogen atom represented by Y is not particularly limited, and examples thereof include a nitrogen atom, a phosphorus atom, an arsenic atom, an antimony atom, and a bismuth atom. These nictogen atoms may be substituted with an alkyl group having 1 to 6 carbon atoms. Examples of such an alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, and a cyclopropyl group. , A butyl group, a 2-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a cyclohexyl group and the like, and an alkyl group having 1 to 4 carbon atoms is preferable in terms of good coloring as a dye, More preferred is a methyl group.

  Y is preferably a nitrogen atom which may be substituted with a sulfur atom or an alkyl group having 1 to 6 carbon atoms, and may be substituted with a sulfur atom or a methyl group in terms of good coloring as a dye. More preferred is a good nitrogen atom.

  n represents an integer of 1 to 5. In terms of easy synthesis, n is preferably 1.

  Although it does not specifically limit as a nitrophenol compound of this invention, For example, the compound of the structure shown below can be illustrated concretely.

次に、本発明のニトロフェノール化合物（１）の製造方法について説明する。

Next, the manufacturing method of the nitrophenol compound (1) of this invention is demonstrated.

  The nitrophenol compound (1) of the present invention can be produced by Step 1 shown in the following reaction formula.

（式中、Ｒ^１はｔｅｒｔ−ブチルオキシカルボニル基又は炭素数１〜４のアルキル基を表す。Ｒ^２ａ、Ｒ^２ｂ、Ｒ^２ｃ、Ｒ^２ｄ、Ｒ^３、Ｙ及びｎは前記と同じ意味を表す。Ｒ^４は、各々独立して、炭素数１〜４のアルキル基又はフェニル基を表す。Ｌは脱離基を表す。）
工程１は、スズ化合物（２ａ）とベンゼン化合物（３ａ）とを、パラジウム触媒の存在下にカップリング反応させ、本発明のニトロフェノール化合物（１）を製造する工程であり、一般的なＳｔｉｌｌｅ反応の反応条件を適用することにより、収率よく目的物を得ることができる。

(In the formula, R ¹ represents a tert-butyloxycarbonyl group or an alkyl group having 1 to 4 carbon atoms. R ^2a , R ^2b , R ^2c , R ^2d , R ³ , Y and n represent the same meaning as described above. R ⁴ each independently represents an alkyl group having 1 to 4 carbon atoms or a phenyl group, and L represents a leaving group.)
Step 1 is a step for producing a nitrophenol compound (1) of the present invention by coupling a tin compound (2a) and a benzene compound (3a) in the presence of a palladium catalyst. By applying the above reaction conditions, the target product can be obtained in good yield.

The alkyl group having 1 to 4 carbon atoms represented by R ¹ may be any of a linear, branched or cyclic alkyl group, and is not particularly limited. Specifically, a methyl group, an ethyl group, Examples include propyl group, isopropyl group, cyclopropyl group, butyl group, 2-butyl group, tert-butyl group, cyclobutyl group and the like.

R ¹ is preferably a tert-butyloxycarbonyl group or a linear alkyl group having 1 to 4 carbon atoms, and more preferably a methyl group in terms of easy synthesis.

The alkyl group having 1 to 4 carbon atoms represented by R ^4, is not particularly limited, and may be exemplified by the same alkyl group having 1 to 4 carbon atoms exemplified by the R ¹ . Among them, a linear alkyl group is preferable in terms of a good yield, and a methyl group or a butyl group is more preferable in terms of easy handling.

  Examples of the leaving group represented by L include halogen atoms such as chlorine atom, bromine atom and iodine atom, sulfonates such as p-toluenesulfonate, methanesulfonate and trifluoromethanesulfonate, and hydrogen atoms. Etc. Of these, a bromine atom or an iodine atom is preferable in terms of good reactivity.

  The tin compound (2a) used in Step 1 is manufactured using, for example, the method disclosed in Chemistry of Materials, 2002, Vol. 14, pp. 1884-1890, or the method shown in Reference Example 1 described later. Can do.

  The benzene compound (3a) used in Step 1 can be produced, for example, using the method shown in Reference Example 2 or 3 described later. Moreover, you may use a commercial item. Although there is no restriction | limiting in particular in the molar ratio of a tin compound (2a) and a benzene compound (3a), 1: 10-10: 1 are preferable and 1: 5-2: 1 are more preferable at the point with a sufficient yield.

  Specific examples of the palladium catalyst used in Step 1 include salts of palladium chloride, palladium acetate, palladium trifluoroacetate, palladium nitrate, and the like. Further, complex compounds such as π-allyl palladium chloride dimer, palladium acetylacetonate, tris (dibenzylideneacetone) dipalladium, dichlorobis (triphenylphosphine) palladium, tetrakis (triphenylphosphine) palladium, dichloro (1,1 Palladium complexes having a tertiary phosphine as a ligand such as' -bis (diphenylphosphino) ferrocene) palladium and bis (tri-tert-butylphosphine) palladium can be exemplified. Among them, a palladium complex having a tertiary phosphine as a ligand is preferable in terms of a good yield, and a palladium complex having triphenylphosphine as a ligand is more preferable. Although there is no restriction | limiting in the quantity of the palladium catalyst used at the process 1, The molar ratio of a palladium catalyst and a tin compound (3a) has a preferable yield ratio, and 1: 50-1: 10 are preferable.

  In addition, the palladium complex which has these tertiary phosphine as a ligand can also add a tertiary phosphine to a palladium salt or a complex compound, and can also prepare it in a reaction system. Specific examples of the tertiary phosphine include triphenylphosphine, trimethylphosphine, tributylphosphine, tri (tert-butyl) phosphine, tricyclohexylphosphine, tert-butyldiphenylphosphine, 9,9-dimethyl-4,5- Bis (diphenylphosphino) xanthene, 2- (diphenylphosphino) -2 ′-(N, N-dimethylamino) biphenyl, 2- (di-tert-butylphosphino) biphenyl, 2- (dicyclohexylphosphino) biphenyl Bis (diphenylphosphino) methane, 1,2-bis (diphenylphosphino) ethane, 1,3-bis (diphenylphosphino) propane, 1,4-bis (diphenylphosphino) butane, 1,1′- Bis (diphenylphosphino) ferrocene, Li (2-furyl) phosphine, tri (o-tolyl) phosphine, tris (2,5-xylyl) phosphine, (±) -2,2′-bis (diphenylphosphino) -1,1′-binaphthyl, 2 -Dicyclohexylphosphino-2 ', 4', 6'-triisopropylbiphenyl and the like can be exemplified. Of these, triphenylphosphine is preferable because it is readily available and yields are good. The molar ratio of the tertiary phosphine to the palladium salt or complex compound is preferably 1: 2 to 20: 1 for the tertiary phosphine: palladium salt or complex compound, and 1: 2 in terms of good yield. A range of 10: 1 is more preferred.

  Step 1 can be carried out in a solvent. There is no restriction | limiting in particular in the solvent which can be used, What is necessary is just a solvent which does not inhibit reaction. Specific examples of such solvents include diethyl ether, tetrahydrofuran (THF), ethers such as 1,2-dimethoxyethane, 1,4-dioxane, and aromatic hydrocarbons such as toluene, xylene, and mesitylene. Examples thereof include amides such as dimethylformamide (DMF), dimethylacetamide, N-methylpyrrolidone and tetramethylurea, dimethyl sulfoxide, and the like, and these may be mixed at an arbitrary ratio. There is no restriction | limiting in particular in the usage-amount of a solvent. Of these, THF, 1,4-dioxane, DMF and a mixed solvent thereof are preferably used in terms of good yield, and DMF is more preferable.

  Although there is no restriction | limiting in particular in the reaction temperature at the time of implementing the process 1, It can implement at the temperature suitably selected from 0-200 degreeC. It is preferable to carry out at a temperature appropriately selected from 40 to 130 ° C. in terms of a good yield.

  The nitrophenol compound (1) of the present invention can be obtained by performing ordinary treatment after completion of the reaction in Step 1. You may refine | purify by neutralization, recrystallization, column chromatography, or sublimation as needed. Moreover, you may use for the following process, without refine | purifying.

  In the above step 1, in addition to the nitrophenol compound (1), the following general formula (1b)

（式中、Ｒ^１、Ｒ^２ａ、Ｒ^２ｂ、Ｒ^２ｃ、Ｒ^２ｄ、Ｒ^３、Ｙ及びｎは前記と同じ意味を表す。）
で示されるフェニルエーテル化合物（以下、「フェニルエーテル化合物（１ｂ）」とも称する）が併産される場合があるが、該フェニルエーテル化合物（１ｂ）は次の反応式に示される工程２によって、本発明のニトロフェノール化合物（１）へと変換することができる。

(In the formula, R ¹ , R ^2a , R ^2b , R ^2c , R ^2d , R ³ , Y and n represent the same meaning as described above.)
In some cases (hereinafter also referred to as “phenyl ether compound (1b)”), the phenyl ether compound (1b) is produced by step 2 shown in the following reaction formula. It can be converted to the nitrophenol compound (1) of the invention.

（式中、Ｒ^１、Ｒ^２ａ、Ｒ^２ｂ、Ｒ^２ｃ、Ｒ^２ｄ、Ｒ^３、Ｙ、Ｌ及びｎは前記と同じ意味を表す。）
工程２は、第三級アミン及びハロゲン化金属塩の存在下、フェニルエーテル化合物（１ｂ）を反応させ、本発明のニトロフェノール化合物（１）を製造する工程である。

(In the formula, R ¹ , R ^2a , R ^2b , R ^2c , R ^2d , R ³ , Y, L and n represent the same meaning as described above.)
Step 2 is a step for producing the nitrophenol compound (1) of the present invention by reacting the phenyl ether compound (1b) in the presence of a tertiary amine and a metal halide salt.

  The tertiary amine that can be used in Step 2 is not particularly limited. For example, tertiary alkylamines such as trimethylamine, triethylamine, diisopropylethylamine, and tributylamine, cyclic azines such as pyridine, pyrazine, and quinoline, Tertiary cyclic amines such as N-methylpyrrolidine, N-methylpiperidine, N, N′-dimethylpiperazine, N-methylmorpholine, diazabicycloundecene, 1,4-diazabicyclo [2.2.2] octane It can be illustrated. Among these, a cyclic azine is preferable in terms of good reaction yield, and pyridine or quinoline is more preferable in terms of low cost.

  There is no restriction | limiting in particular in the quantity of the tertiary amine used for the process 2, You may use as a reaction solvent.

  The metal halide salt that can be used in the step 2 is not particularly limited, but lithium chloride, lithium fluoride, lithium bromide, lithium iodide, sodium chloride, sodium fluoride, sodium bromide, iodide. Sodium metal halides such as potassium chloride, potassium fluoride, potassium bromide, potassium iodide, cesium chloride, cesium fluoride, cesium bromide, cesium iodide, magnesium chloride, magnesium fluoride, magnesium bromide, Examples thereof include alkaline earth metal halides such as magnesium iodide, calcium chloride, calcium fluoride, calcium bromide, calcium iodide, barium chloride, barium fluoride, barium bromide and barium iodide. Of these, alkali metal halides are preferred in terms of good solubility, and lithium iodide is more preferred in terms of good reaction yield. The molar ratio between the metal halide salt and the phenyl ether compound (1b) is not particularly limited, but is preferably 10: 1 to 1: 2, and more preferably 5: 1 to 1: 1 in terms of a good yield.

  Step 2 can be carried out in a solvent. There is no restriction | limiting in particular in the solvent which can be used, What is necessary is just a solvent which does not inhibit reaction.

  Although there is no restriction | limiting in particular in the reaction temperature at the time of implementing the process 2, It can implement at the temperature suitably selected from 0-200 degreeC. It is preferable to carry out at a temperature appropriately selected from 40 to 130 ° C. in terms of a good yield.

  The nitrophenol compound (1) of the present invention can be obtained by performing a normal treatment after completion of the reaction in Step 2. You may refine | purify by neutralization, recrystallization, column chromatography, or sublimation as needed. Moreover, you may use for the following process, without refine | purifying.

  When the nitrophenol compound (1) of the present invention is used in various paints, water-based or oil-based inks, ink jet inks, color filters for display elements, etc., the nitrophenol compound (1) of the present invention is prepared according to the following method. A dye composition containing the composition (hereinafter referred to as “the dye composition”) can be produced.

  The dye composition can be produced by kneading the nitrophenol compound (1) of the present invention, a solvent, an emulsifier and a thickener.

  The content of the nitrophenol compound (1) of the present invention relative to the dye composition is 1 to 50% by weight, preferably 5 to 20% by weight.

  Examples of the solvent used in the production of the dye composition include water and other hydrophilic solvents such as alcohols having 1 to 4 carbon atoms, DMF, and dimethyl sulfoxide, and these may be used in combination. The content of the solvent with respect to the dye composition is 1 to 99% by weight, preferably 50 to 70% by weight.

  Examples of emulsifiers used in the production of the dye composition include anionic surfactants such as carboxylates, sulfonates, and nitrate esters, cationic surfactants such as quaternary ammonium salts, and non-valent agents such as polyhydric alcohols. An ionic surfactant can be mentioned, and these may be mixed and used in an arbitrary ratio. The content of the emulsifier in the dye composition is 0.1 to 30% by weight, preferably 1 to 15% by weight.

  Examples of the thickener used in the production of the dye composition include polyethylene glycol (PEG), polypropylene glycol (PPG), polyvinyl chloride, polyethylene, polymethacrylate, and the like. You may mix and use by arbitrary ratios. The content of the thickener in the dye composition is 0.1 to 30% by weight, preferably 1 to 15% by weight.

  As a kneading method used for the production of the dye composition, a general method such as stirring, shaking, or ball mill can be used.

  EXAMPLES Hereinafter, although an Example and a reference example demonstrate this invention further in detail, this invention is limited to these and is not interpreted.

  Example-1

アルゴン雰囲気下、参考例−２にて合成した４−ブロモ−２−ニトロ−（Ｏ−ｔｅｒｔ−ブチルオキシカルボニル）フェノール（３７２μＬ，１．５ｍｍｏｌ）及びビス（トリフェニルホスフィン）パラジウムジクロリド（２１ｍｇ，０．０３ｍｍｏｌ）を参考例−１にて合成した５−［４−（Ｎ，Ｎ−ジフェニルアミノ）フェニル］−２−（トリメチルスタニル）チオフェン（１．０ｍｍｏｌ）のＤＭＦ（１０ｍＬ）溶液に加えた。この混合物を９０℃にて２０時間撹拌した。放冷後、反応混合物に水を加え、クロロホルムで有機層を抽出した。有機層に硫酸マグネシウムを加えて撹拌した後、ろ液を取得し、該ろ液から溶媒を減圧留去した。得られた粗生成物をシリカゲルカラムクロマトグラフィー（溶離液：ヘキサン／クロロホルム）により精製することで、目的の４−｛５−［４−（Ｎ，Ｎ−ジフェニルアミノ）フェニル］チオフェン−２−イル｝−２−ニトロフェノールを赤色固体として得た（２０９ｍｇ，４５％）。

Under an argon atmosphere, 4-bromo-2-nitro- (O-tert-butyloxycarbonyl) phenol (372 μL, 1.5 mmol) and bis (triphenylphosphine) palladium dichloride (21 mg, 0) synthesized in Reference Example-2 were used. .03 mmol) was added to a DMF (10 mL) solution of 5- [4- (N, N-diphenylamino) phenyl] -2- (trimethylstannyl) thiophene (1.0 mmol) synthesized in Reference Example-1. . The mixture was stirred at 90 ° C. for 20 hours. After allowing to cool, water was added to the reaction mixture, and the organic layer was extracted with chloroform. After adding magnesium sulfate to the organic layer and stirring, a filtrate was obtained, and the solvent was distilled off from the filtrate under reduced pressure. The obtained crude product was purified by silica gel column chromatography (eluent: hexane / chloroform) to give the desired 4- {5- [4- (N, N-diphenylamino) phenyl] thiophen-2-yl. } -2-Nitrophenol was obtained as a red solid (209 mg, 45%).

¹ H-NMR (400 MHz, CDCl ₃ ): δ 10.6 (s, 1H), 8.31 (d, J = 2.3 Hz, 1H), 7.83 (dd, J = 8.8, 2.3 Hz) , 1H), 7.48 (d, J = 8.8 Hz, 2H), 7.25-7.30 (m, 5H), 7.20 (d, J = 3.8 Hz, 1H), 7.20 (D, J = 8.8 Hz, 1H), 7.13 (dd, J = 8.6, 1.1 Hz, 4H), 7.08 (d, J = 8.8 Hz, 2H), 7.05- 7.08 (m, 2H).
The maximum absorption wavelength of this compound was 378 nm, and the absorption edge was 568 nm. The molar extinction coefficient at the maximum absorption wavelength was 33200 [L · mol ⁻¹ · cm ⁻¹ ].

  Example-2

アルゴン雰囲気下、参考例−３にて合成した４−ブロモ−２，６−ジニトロアニソール（４０ｍｇ，０．１４ｍｍｏｌ）及びビス（トリフェニルホスフィン）パラジウムジクロリド（３．１ｍｇ，０．００５ｍｍｏｌ）を、参考例−１にて合成した２−［４−（Ｎ，Ｎ−ジフェニルアミノ）フェニル］チオフェン（１．０ｍｍｏｌ）のＤＭＦ（１０ｍＬ）溶液に加えた。この混合物を９０℃にて２０時間撹拌した。放冷後、反応混合物に水を加え、クロロホルムで有機層を抽出した。有機層に硫酸マグネシウムを加えて撹拌した後、ろ液を取得し、該ろ液から溶媒を減圧留去した。得られた粗生成物をシリカゲルカラムクロマトグラフィー（溶離液：ヘキサン／クロロホルム）により精製することで、目的の２，６−ジニトロ−４−｛５−［４−（Ｎ，Ｎ−ジフェニルアミノ）フェニル］チオフェン−２−イル｝フェノールを赤色固体として得た（３５ｍｇ，４９％）。

Reference was made to 4-bromo-2,6-dinitroanisole (40 mg, 0.14 mmol) and bis (triphenylphosphine) palladium dichloride (3.1 mg, 0.005 mmol) synthesized in Reference Example-3 under an argon atmosphere. 2- [4- (N, N-diphenylamino) phenyl] thiophene (1.0 mmol) synthesized in Example-1 was added to a DMF (10 mL) solution. The mixture was stirred at 90 ° C. for 20 hours. After allowing to cool, water was added to the reaction mixture, and the organic layer was extracted with chloroform. After adding magnesium sulfate to the organic layer and stirring, a filtrate was obtained, and the solvent was distilled off from the filtrate under reduced pressure. The obtained crude product was purified by silica gel column chromatography (eluent: hexane / chloroform) to obtain the desired 2,6-dinitro-4- {5- [4- (N, N-diphenylamino) phenyl. ] Thiophen-2-yl} phenol was obtained as a red solid (35 mg, 49%).

¹ H-NMR (400 MHz, CDCl ₃ ): δ 11.4 (s, 1H), 8.49 (s, 2H), 7.4 (d, J = 8.7 Hz, 2H), 7.34 (d, J = 3.9 Hz, 1H), 7.25-7.30 (m, 4H), 7.23 (d, J = 3.9 Hz, 1H), 7.13 (dd, J = 8.6, 1 .1 Hz, 4H), 7.07-7.09 (m, 2H), 7.05-7.08 (m, 2H).
The maximum absorption wavelength of this compound was 388 nm, and the absorption edge was 577 nm. The molar extinction coefficient at the maximum absorption wavelength was 29600 [L · mol ⁻¹ · cm ⁻¹ ].

  Reference Example-1

アルゴン雰囲気下、４−ブロモトリフェニルアミン（４．８０ｇ，１３．９ｍｍｏｌ）、ビス（トリフェニルホスフィン）パラジウムジクロリド（２８１ｍｇ，０．４ｍｍｏｌ）及び２−（トリブチルスタニル）チオフェン（８．８０ｍＬ，２７．７ｍｍｏｌ）を、ＤＭＦ（５０ｍＬ）に溶解した。この混合物を１００℃にて２０時間撹拌した。放冷後、反応混合物に水を加え、クロロホルムで有機層を抽出した。有機層に硫酸マグネシウムを加えて撹拌した後、ろ液を取得し、該ろ液から溶媒を減圧留去した。得られた粗生成物をシリカゲルカラムクロマトグラフィー（溶離液：ヘキサン／酢酸エチル）により精製することで黄褐色固体の２−［４−（Ｎ，Ｎ−ジフェニルアミノ）フェニル］チオフェンを得た（３．５０ｇ，７８％）。

Under an argon atmosphere, 4-bromotriphenylamine (4.80 g, 13.9 mmol), bis (triphenylphosphine) palladium dichloride (281 mg, 0.4 mmol) and 2- (tributylstannyl) thiophene (8.80 mL, 27 0.7 mmol) was dissolved in DMF (50 mL). The mixture was stirred at 100 ° C. for 20 hours. After allowing to cool, water was added to the reaction mixture, and the organic layer was extracted with chloroform. After adding magnesium sulfate to the organic layer and stirring, a filtrate was obtained, and the solvent was distilled off from the filtrate under reduced pressure. The obtained crude product was purified by silica gel column chromatography (eluent: hexane / ethyl acetate) to obtain 2- [4- (N, N-diphenylamino) phenyl] thiophene as a tan solid (3 .50 g, 78%).

¹ H-NMR (400 MHz, CDCl ₃ ): δ 7.47 (d, J = 8.8 Hz, 2H), 7.24-7.28 (m, 4H), 7.21-7.23 (m, 2H) ), 7.12 (dd, J = 8.1, 1.1 Hz, 4H), 7.03-7.08 (m, 3H), 7.07 (d, J = 8.8 Hz, 2H).
Under an argon atmosphere, synthesized 2- [4- (N, N-diphenylamino) phenyl] thiophene (654 mg, 2.0 mmol) was added in THF (20 mL) and cooled to -78 ° C. An n-BuLi hexane solution (1.62M, 1.9 mL, 3.0 mmol) was added thereto and stirred for 15 minutes, and then trimethyltin chloride (1.10 g, 5.7 mmol) was further added. The mixture was stirred at the above temperature for 30 minutes and then at room temperature for 12 hours. After completion of the reaction, water was added to the reaction mixture, and the organic layer was extracted with chloroform. After adding magnesium sulfate to the organic layer and stirring, a filtrate is obtained, and the solvent is distilled from the filtrate under reduced pressure to obtain the desired 5- [4- (N, N-diphenylamino) phenyl] -2- (Trimethylstannyl) thiophene was obtained as a tan oil. This compound was used in the next step without purification.

¹ H-NMR (400 MHz, CDCl ₃ ): δ 7.47 (d, J = 8.7 Hz, 2H), 7.33 (d, J = 3.4 Hz, 1H), 7.28 (m, 4H), 7.14 (d, J = 3.4 Hz, 1H), 7.11 (dd, J = 8.7, 1.1 Hz, 4H), 7.06 (d, J = 8.8 Hz, 2H), 7 .00-7.05 (m, 2H), 0.38 (s, 9H).
Reference example-2

アルゴン雰囲気下、４−ブロモ−２−ニトロフェノール（１．０ｇ，４．６ｍｍｏｌ）及びジ−ｔｅｒｔ−ブチルジカルボネート（１．６ｍＬ，６．９ｍｍｏｌ）をヘキサン（１２ｍＬ）及びクロロホルム（１２ｍＬ）の混合溶媒に溶解し０℃に冷却した。ここに４−ジメチルアミノピリジン（２８ｍｇ，０．２ｍｍｏｌ）を加え、７０℃にて２４時間撹拌した。放冷後、反応混合物に飽和食塩水を加え、酢酸エチルで有機層を抽出した。有機層に硫酸マグネシウムを加えて撹拌した後、ろ液を取得し、該ろ液から溶媒を減圧留去することで、目的の４−ブロモ−２−ニトロ−（Ｏ−ｔｅｒｔ−ブチルオキシカルボニル）フェノールを黄色油状物として得た（１．５ｇ，ｑｕａｎｔ．）。

Under an argon atmosphere, 4-bromo-2-nitrophenol (1.0 g, 4.6 mmol) and di-tert-butyl dicarbonate (1.6 mL, 6.9 mmol) were mixed with hexane (12 mL) and chloroform (12 mL). It melt | dissolved in the solvent and cooled to 0 degreeC. 4-Dimethylaminopyridine (28 mg, 0.2 mmol) was added here, and it stirred at 70 degreeC for 24 hours. After allowing to cool, saturated brine was added to the reaction mixture, and the organic layer was extracted with ethyl acetate. Magnesium sulfate is added to the organic layer and stirred, and then a filtrate is obtained. The solvent is distilled off from the filtrate under reduced pressure to obtain the desired 4-bromo-2-nitro- (O-tert-butyloxycarbonyl). Phenol was obtained as a yellow oil (1.5 g, quant.).

¹ H-NMR (400 MHz, CDCl ₃ ): δ 8.25 (d, J = 2.4 Hz, 1H), 7.76 (dd, J = 8.6, 2.4 Hz, 1H), 7.21 (d , J = 8.6 Hz, 1H), 1.57 (s, 9H).
Reference example-3

４−ブロモ−２−ニトロフェノール（３．０ｇ，１３．８ｍｍｏｌ）をジクロロメタン（７０ｍＬ）に溶解し０℃に冷却した。ここに発煙硝酸（１．５Ｍ，２０ｍＬ，３０ｍｍｏｌ）を滴下した後、室温にて３時間撹拌した。次いで、反応混合物を氷水に加え、クロロホルムを用いて有機層を抽出した。有機層に硫酸マグネシウムを加えて撹拌した後、ろ液を取得し、該ろ液から溶媒を減圧留去することで、橙色固体の４−ブロモ−２，６−ジニトロフェノールを得た（１．９ｇ，５３％）。

4-Bromo-2-nitrophenol (3.0 g, 13.8 mmol) was dissolved in dichloromethane (70 mL) and cooled to 0 ° C. Fuming nitric acid (1.5 M, 20 mL, 30 mmol) was added dropwise thereto, followed by stirring at room temperature for 3 hours. The reaction mixture was then added to ice water, and the organic layer was extracted with chloroform. After adding magnesium sulfate to the organic layer and stirring, the filtrate was obtained, and the solvent was distilled off from the filtrate under reduced pressure to obtain 4-bromo-2,6-dinitrophenol as an orange solid (1. 9g, 53%).

¹ H-NMR (400 MHz, CDCl ₃ ): δ 11.3 (s, 1H), 8.44 (s, 2H).
Under an argon atmosphere, the synthesized 4-bromo-2,6-dinitrophenol (367 mg, 1.4 mmol) was dissolved in a mixed solvent of acetonitrile (20 mL) and methanol (2.2 mL). Trimethylsilyldiazomethane-hexane solution (2M, 2.4 mL, 4.8 mmol) was added thereto, and the mixture was stirred at room temperature for 13 hours. Next, water was added to the reaction mixture, and the organic layer was extracted with chloroform. After adding magnesium sulfate to the organic layer and stirring, a filtrate was obtained, and the solvent was distilled off from the filtrate under reduced pressure to obtain the desired 4-bromo-2,6-dinitroanisole as a red solid ( 338 mg, 87%).

¹ H-NMR (400 MHz, CDCl ₃ ): δ 8.17 (s, 2H), 4.07 (s, 3H).

Claims (4)

General formula (1)

(In the formula, R ^2a , R ^2b , R ^2c and R ^2d each independently represent a hydrogen atom or a nitro group, provided that R ^2a , R ^2b , R ^2c and R ^2d are all hydrogen atoms at the same time. R ³ each independently represents a hydrogen atom or an alkyloxy group having 1 to 12 carbon atoms, and Y represents a nicotine atom which may be substituted with a chalcogen atom or an alkyl group having 1 to 6 carbon atoms. N represents an integer of 1 to 5.)
A nitrophenol compound represented by The nitrophenol compound according to claim 1, wherein the chalcogen atom is a sulfur atom. The nitrophenol compound according to claim 1 or 2, wherein n is 1. General formula (2a)

(In the formula, each R ³ independently represents a hydrogen atom or an alkyloxy group having 1 to 12 carbon atoms. Each R ⁴ independently represents an alkyl group having 1 to 4 carbon atoms or a phenyl group. Y Represents a chalcogen atom or a nictogen atom optionally substituted with an alkyl group having 1 to 6 carbon atoms, and n represents an integer of 1 to 5.)
A tin compound represented by the general formula (3a)

(In the formula, R ¹ represents an alkyl group having 1 to 4 carbon atoms or a tert-butyloxycarbonyl group. R ^2a , R ^2b , R ^2c and R ^2d each independently represents a hydrogen atom or a nitro group. (However, R ^2a , R ^2b , R ^2c and R ^2d cannot all be hydrogen atoms at the same time. L represents a leaving group.)
The method for producing a nitrophenol compound according to claim 1, wherein a coupling reaction is carried out with a benzene compound represented by the formula (I) in the presence of a palladium catalyst.