JP2001163880A - METHOD FOR PRODUCING THIOCHROMAN-6-CARBOXYLIC ACID DERIVATIVE OR DIHYDROBENZO[b]THIOPHENE-5-CARBOXYLIC ACID DERIVATIVE - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for inexpensively producing a thiochroman-6- carboxylic acid derivative and a dihydrobenzo[b]thiophene-5-carboxylic acid derivative having high usability as intermediates for producing a pyrazole derivative and a cyclohexanedione derivative which are active ingredients for herbicides in small environmental load. SOLUTION: This method for producing a thiochroman-6-carboxylic acid derivative or a dihydrobenzo[b]thiophene-5-carboxylic acid derivative comprises reducing a halide represented by the general formula [1], wherein R1 is a halogen atom or an alkyl group; R2 to R5 are each hydrogen atom or an alkyl group; Z1 is C(R6R7) group, wherein R6 and R7 are each hydrogen atom, an alkyl group or an alkoxy group; X is Cl, Br or I atom; (n) is 0 or 1 in an aqueous solution of an alkali in the presence of zinc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a thiochroman-6-carboxylic acid derivative and dihydrobenzo [b] thiophen-5- highly useful as intermediates for producing pyrazole derivatives and cyclohexanedione derivatives which are active ingredients of herbicides. The present invention relates to a method for producing a carboxylic acid derivative with low environmental load and low production cost.

[0002]

2. Description of the Related Art Herbicides are extremely important agents for saving labor for weed control and improving productivity of agricultural and horticultural crops.
For this reason, research and development of herbicides have been actively carried out for many years, and various kinds of drugs have been put to practical use. However, even today, there is a demand for the development of a new drug having more excellent herbicidal properties, particularly a drug capable of controlling only the target weed selectively and at a low dose without causing phytotoxicity to cultivated crops. .

Conventionally, at the time of cultivation of corn and the like, atrazine, which is a triazine herbicide, and arachlor and metolachlor, which are acid anilide herbicides, have been used. Conversely, chlor and metolachlor have low activity against broadleaf weeds. Therefore, it is currently difficult to control grasses and broadleaf weeds at once with a single agent. In addition, these herbicides require high doses,
Not good for environmental hygiene.

[0004] In order to solve such a problem, international application WO 93/18031 and international application WO 94/01 have been proposed.
431, International Application WO 96/25412,
International application WO96 / 30368, International application WO9
JP-A-7 / 03064 proposes a novel pyrazole derivative and a novel cyclohexanedione derivative having a thiochroman ring and a dihydrobenzo [b] thiophene ring.

[0005] The novel pyrazole derivatives and novel cyclohexanedione derivatives described in these international application specifications are:
General formula (A),

[0006]

Embedded image

The thiochroman-6-carboxylic acid derivative and dihydrobenzo [b] thiophen-5-carboxylic acid derivative represented by the general formula (B) or the general formula (C) are prepared in the presence of a dehydrating agent and a base.

[0008]

Embedded image

It is produced by reacting with a pyrazole derivative or a cyclohexanedione derivative represented by Further, in International Application WO 93/18031, the compound (a) wherein X ⁴ in the thiochroman-6-carboxylic acid derivative and the dihydrobenzo [b] thiophen-5-carboxylic acid derivative (A) is hydrogen
The following reaction is disclosed as a method for producing.

[0010]

Embedded image

In the above-mentioned production method, zinc is used in an amount of 3.0 equivalents to the raw material, and ethanol as a solvent is used in an amount of 2 equivalents to the raw material.
It is necessary to use 5 equivalents, which is not industrially advantageous.
Further, since the amount of waste liquid accompanying the reaction is large, there are disadvantages in that the equipment cost and utility cost required for the treatment are increased, and the environmental load is increased due to the treatment.

Further, International Application WO 96/30368 discloses the following reaction.

[0013]

Embedded image

In this production method, the reaction is carried out using tetrahydrofuran as a reaction solvent and pyridine as an organic base. However, since these solvents and organic bases are expensive, the production cost increases. In addition, the amount of waste liquid generated in the course of this reaction is large, so that equipment costs and utility costs required for the treatment are increased, and there is a problem that these treatments increase the environmental load.

[0015]

DISCLOSURE OF THE INVENTION The present invention relates to a thiochroman-6-carboxylic acid derivative and dihydrobenzo [b] which are highly useful as intermediates for producing pyrazole derivatives and cyclohexanedione derivatives as active ingredients of herbicides.
A method for producing an industrially advantageous thiochroman-6-carboxylic acid derivative and dihydrobenzo [b] thiophen-5-carboxylic acid derivative, which is a thiophen-5-carboxylic acid derivative which has a small environmental load and a low production cost. The purpose is to provide.

[0016]

Means for Solving the Problems The inventors of the present invention have conducted various studies to solve the above-mentioned problems, and as a result, have found that the precursor of the target compound is reduced in an aqueous alkaline solution to produce the target compound. The present inventors have found that the object of the present invention can be achieved, and have completed the present invention based on these findings.

That is, the gist of the present invention is as follows. (1) General formula [1],

[0018]

Embedded image

Wherein R ¹ represents a halogen atom or an alkyl group having 1 to 4 carbon atoms, and R ² , R ³ , R ⁴ , R ⁵
Each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, X represents a chlorine atom, a bromine atom or an iodine atom, and n represents 1 or 0. Z ¹ is a general formula [2],

[0020]

Embedded image

(Wherein R ⁶ and R ⁷ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or
Represents an alkoxy group. Further, when R ⁶ and R ⁷ are each independently both alkyl groups or together alkoxy group having 1 to 4 carbon atoms 1 to 4 carbon atoms, R ⁶ and R ⁷ and are each optionally on the carbon atoms To form a spiro type 3 ~
It may form a 7-membered ring. ). In an aqueous alkali solution,
General formula [3], characterized in that reduction is performed using zinc.

[0022]

Embedded image

[Wherein, R ¹ represents a halogen atom or an alkyl group having 1 to 4 carbon atoms, and R ² , R ³ , R ⁴ , R ⁵
Each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and n represents 1 or 0. Z ¹ is a general formula [2],

[0024]

Embedded image

(Wherein R ⁶ and R ⁷ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or
Represents an alkoxy group. Further, when R ⁶ and R ⁷ are each independently both alkyl groups or together alkoxy group having 1 to 4 carbon atoms 1 to 4 carbon atoms, R ⁶ and R ⁷ and are each optionally on the carbon atoms To form a spiro type 3 ~
It may form a 7-membered ring. ). The method for producing a thiochroman-6-carboxylic acid derivative or a dihydrobenzo [b] thiophen-5-carboxylic acid derivative represented by the following formula: (2) General formula [4],

[0026]

Embedded image

[Wherein R ¹ represents a halogen atom or an alkyl group having 1 to 4 carbon atoms, and R ² , R ³ , R ⁴ , R ⁵
Each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, X represents a chlorine atom, a bromine atom or an iodine atom, and n represents 1 or 0. Z ² has the general formula [5] or [6],

[0028]

Embedded image

(Wherein, R ⁸ and R ⁹ each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group wherein both R ⁸ and R ⁹ have 1 to 4 carbon atoms. R ⁸
And R ⁹ are each independently an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, R ⁶ and R ⁷ are bonded to each other on an arbitrary carbon atom. To form a spiro-type saturated hydrocarbon ring having a 3 to 7-membered ring structure or an oxygen-containing saturated hydrocarbon ring. Also R
¹⁰ represents an oxygen atom, a sulfur atom or an alkoxyimino group having 1 to 4 carbon atoms. ). General formula [7], characterized in that the halide represented by the formula (1) is reduced with hydrogen in an aqueous alkali solution in the presence of a metal catalyst.

[0030]

Embedded image

[Wherein, R ¹ represents a halogen atom or an alkyl group having 1 to 4 carbon atoms, and R ² , R ³ , R ⁴ , R ⁵
Each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. n represents 1 or 0, and Z ² represents the general formula [5] or [6],

[0032]

Embedded image

(Wherein, R ⁸ and R ⁹ each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group wherein both R ⁸ and R ⁹ have 1 to 4 carbon atoms. R ⁸
And R ⁹ are each independently an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, R ⁶ and R ⁷ are bonded to each other on an arbitrary carbon atom. To form a spiro-type saturated hydrocarbon ring having a 3 to 7-membered ring structure or an oxygen-containing saturated hydrocarbon ring. Also R
¹⁰ represents an oxygen atom, a sulfur atom or an alkoxyimino group having 1 to 4 carbon atoms. ). The method for producing a thiochroman-6-carboxylic acid derivative or a dihydrobenzo [b] thiophen-5-carboxylic acid derivative represented by the following formula:

[0034]

DETAILED DESCRIPTION OF THE INVENTION The thiochroman-6-carboxylic acid derivative of the present invention or dihydrobenzo [b] thiophene-
In the method for producing a 5-carboxylic acid derivative, a halide represented by the general formula [1] is used as a raw material. In the compound represented by the general formula [1], examples of the halogen atom represented by R ¹ include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. In addition, general formulas [1], [2], [4] and [5]
Wherein the alkyl group having 1 to 4 carbon atoms represented by R ^{1 to} R ⁹ includes a methyl group, an ethyl group, an n-propyl group,
Propyl and n-butyl, such as -propyl, i
And butyl groups such as -butyl group, sec-butyl group and t-butyl group.

The alkoxy groups having 1 to 4 carbon atoms represented by R ⁶ and R ⁷ in the general formula [2] and R ⁸ and R ⁹ in the general formula [5] include methoxy, ethoxy, n- And propoxy groups such as propoxy group and i-propoxy group, butoxy groups such as n-butoxy group, i-butoxy group, sec-butoxy group and t-butoxy group. In addition, the number of carbon atoms represented by R ¹⁰ in the general formula [6] is 1
Examples of the alkoxyimino groups (1) to (4) include a methoxyimino group, an ethoxyimino group, an n-propoxyimino group, and an i-
And propoxy imino groups such as propoxy imino group, butoxy imino groups such as n-butoxy imino group, i-butoxy imino group, sec-butoxy imino group and t-butoxy imino group.

Further, R ⁶ and R ⁷ in the general formula [2]
And R ⁸ and R ⁹ in the general formula [5] are those R
^{When 6} and R ⁷ or R ⁸ and R ⁹ are each independently an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, they are bonded to each other on an arbitrary carbon atom. To form a spiro-type 3- to 7-membered ring.
When R ⁶ and R ⁷ or R ⁸ and R ⁹ are both an alkyl group having 1 to 4 carbon atoms, examples of the cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group and a cycloheptyl group. Is mentioned. The cycloalkyl group formed here may be substituted by an alkyl group having 1 to 3 carbon atoms, and the total number of carbon atoms of the alkyl-substituted cycloalkyl group is 9 or less.

Further, R ⁶ and R ⁷ or R ⁸ and R ⁹
When both are alkoxy groups having 1 to 4 carbon atoms, examples of the cyclic acetal group include an ethylenedioxy group, a propylenedioxy group, and a butylenedioxy group. The cyclic acetal group formed here may be substituted with an alkyl group having 1 to 3 carbon atoms, and the alkyl-substituted cyclic acetal group may have a total carbon number of 9 or less.

Then, a halide represented by the general formula [1] or [4] of these raw materials, that is,
8-halogenothiochroman-6-carboxylic acid derivative or 7-halogenodihydrobenzo [b] thiophen-5-
Carboxylic acid derivatives are described in the international application WO 93/180 mentioned above.
It can be produced by a production method described in Japanese Patent Application Publication No. 31 or International Application No. WO94 / 01431 or International Application No. WO96 / 25412.

Next, in the first production method of the present invention, the halide represented by the general formula [1] is
By reducing with zinc in an alkaline aqueous solution,
The desired thiochroman-6-carboxylic acid derivative, that is, thiochroman-6 optionally having various substituents
-Carboxylic acid-1,1-dioxide and dihydrobenzo [b] thiophene-5-carboxylic acid derivatives, that is, dihydrobenzo [b] thiophen-5-carboxylic acid-1, which may have various substituents Produce 1-dioxide.

As the alkali compound used for preparing the above-mentioned aqueous alkali solution, a hydroxide salt such as sodium hydroxide and potassium hydroxide and a carbonate salt such as sodium carbonate and potassium carbonate are preferable. Among these compounds, sodium hydroxide or potassium hydroxide is particularly preferred. The use ratio of the alkali compound is 2 to 5 equivalents, preferably 3 to 4 equivalents, relative to the halide represented by the general formula [1] of the raw material. The concentration of the alkaline aqueous solution is preferably 5 to 30% by weight.

Further, the proportion of zinc used here is as follows:
The amount is 1 to 2 equivalents, preferably 1.5 to 2 equivalents, based on the halide of the raw material. If the proportion of zinc used is less than 1 equivalent to the halide of the raw material, the raw material may remain in the product, and the proportion of zinc used may be 2 equivalents to the halide of the raw material. Since the effect corresponding thereto cannot be obtained even if it is used more than that, it is desirable to set it within the above-mentioned usage ratio.

In the reduction reaction, an alcoholic solvent such as methanol or ethanol may be added in an amount of 10 equivalents or less, preferably 4 to 8 equivalents to the halide.

The reaction temperature in this reduction reaction is from 20 ° C. to the reflux temperature of the solvent, preferably from 50 ° C. to 80 ° C. The reaction time is usually 1 to 16
The time is preferably 5 to 10 hours.

In this reaction, in addition to the desired thiochroman-6-carboxylic acid derivative or dihydrobenzo [b] thiophen-5-carboxylic acid derivative, by-products may be produced depending on the reaction conditions. For example,
The following formula,

[0045]

Embedded image

[Wherein R ^{1 to} R ⁵ , Z ¹ and n have the same meanings as R ^{1 to} R ⁵ , Z ¹ and n in the general formula [1]. The dimer of the starting compound represented by the formula

Such compounds include, for example, 8,
8'-bi (4,4,5-trimethylthiochroman-6-
Carboxylic acid-1,1-dioxide), 7,7 ′-(2,
3-dihydro-3,3,4-trimethylbenzo [b] thiophen-5-carboxylic acid-1,1-dioxide),
8,8'-bi (4-methoxy-5-methylthiochroman-6-carboxylic acid-1,1-dioxide), 7,7'-
2,3-dihydro-3-methoxy-4-methylbenzo [b] thiophen-5-carboxylic acid-1,1-dioxide) and the like.

Next, in the second production method of the present invention, the halide represented by the general formula [4] is
Reduction with hydrogen in an aqueous alkali solution in the presence of a metal catalyst allows the desired thiochroman-6-carboxylic acid derivative or dihydrobenzo [b] thiophene-
A 5-carboxylic acid derivative can be obtained.

Regarding the aqueous alkali solution used here,
What is necessary is just to use the same thing as the alkaline aqueous solution in the said 1st manufacturing method. Examples of the metal catalyst used here include a base metal catalyst such as Raney nickel and nickel diatomaceous earth, and a noble metal catalyst such as palladium and platinum oxide. Among these metal catalysts, a noble metal catalyst is preferable, and among them, a palladium catalyst is particularly preferable. It is preferable that these metal catalysts are supported on a carrier such as activated carbon, alumina, silica gel, and barium sulfate. Among these carriers, activated carbon is particularly preferably used. Further, the use ratio of this metal catalyst is 0.1% with respect to the halide represented by the general formula [4] as a raw material.
0 to 3% by weight, preferably 0.35 to 1% by weight.

The hydrogen used for the reduction reaction may be supplied to the reaction system at normal pressure or under pressure. Preferred is a pressurizing condition in which the hydrogen pressure is 4 MPa or less. In addition, the reaction temperature at the time of performing this reduction reaction is 20 ° C. to the reflux temperature of water, preferably 70 ° C. in the reaction at normal pressure.
To 80 ° C, and in the case of pressurization, 20 ° C to 150 ° C, preferably 50 ° C to 120 ° C. The reaction time is generally 1 to 16 hours, preferably 5 to 10 hours.

Further, a small amount of an alcohol solvent such as methanol or ethanol may be added to the reaction system. In this second production method, in addition to the objective thiochroman-6-carboxylic acid derivative or dihydrobenzo [b] thiophen-5-carboxylic acid derivative represented by the general formula [7], the reaction conditions May produce by-products. For example,

[0052]

Embedded image

Wherein R ^{1 to} R ⁵ , Z ² and n have the same meanings as R ^{1 to} R ⁵ , Z ² and n in the general formula [4]. ] May be formed in some cases.

Such compounds include, for example, 8,
8'-bi (4-methoxyimino-5-methylthiochroman-6-carboxylic acid-1,1-dioxide), 7,7 '
-Bi (2,3-dihydro-3-methoxyimino-4-methylbenzo [b] thiophene-5-carboxylic acid-1,1
-Dioxide), 8,8'-bi (6-carboxy3,3)
3,5-trimethylthiochroman-4-one-1,1-
Dioxide), 7,7'-bi (5-carboxy-2,3
-Dihydro-2,2,4-trimethylbenzo [b] thiophen-3-one-1,1-dioxide).

[0055]

EXAMPLES Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

Example 1 Production of 4,4,5-trimethylthiochroman-6-carboxylic acid-1,1-dioxide 8-chloro-4,4,5-trimethylthiochroman-6-carboxylic acid was used as a raw material. Acid-1,1-dioxide 7.2
3 g (24 mmol) was dissolved in 37 ml (88 mmol, 3.7 equivalents) of a 12% by weight aqueous potassium hydroxide solution.
3 mmol, 1.8 equivalents) and stirred at 80 ° C. for 9 hours.

Then, the obtained reaction mixture was cooled to room temperature, and the solid was removed by filtration. 10 mL of concentrated hydrochloric acid was added to the obtained filtrate to adjust the pH to 1, and the mixture was diluted with ethyl acetate to 2 mL.
After extraction twice, the organic layer was washed with saturated saline and dried over anhydrous sodium sulfate. Further, the solvent is distilled off under reduced pressure to give 4,4,5-trimethylthiochroman-6-.
6.22 g of carboxylic acid-1,1-dioxide (yield 83
%, HPLC purity 86%). Table 1 shows the structural formula and ¹ H-NMR data of the obtained compound.

Example 2 Production of 4-methoxy-5-methylthiochroman-6-carboxylic acid-1,1-dioxide In Example 1, 8-chloro-4,
4,5-trimethylthiochroman-6-carboxylic acid-
8-chloro-4-methoxy-5-methylthiochroman-6-carboxylic acid-1,1 in place of 1,1-dioxide
4-methoxy-5-methylthiochroman-6-carboxylic acid-1,1 in the same manner as in Example 1 except that -dioxide was used and ethanol (6.8 equivalents to the starting material) was added as a solvent. -Dioxide was obtained in 98% yield. The structural formula and ¹ H-NMR data of the obtained compound were
It is shown in the table.

Example 3 Preparation of 5-chloro-4,4-dimethylthiochroman-6-carboxylic acid-1,1-dioxide In Example 1, 8-chloro-4,4-chloro-4,4-dimethylthiochroman-6
4,5-trimethylthiochroman-6-carboxylic acid-
Instead of 1,1-dioxide, 5,8-dichloro-4,
4-dimethylthiochroman-6-carboxylic acid-1,1-
Other than using a dioxide and setting the reaction temperature to 50 ° C,
In the same manner as in Example 1, 5-chloro-4,4-dimethylthiochroman-6-carboxylic acid-1,1-dioxide was obtained with a yield of 72%. Structural formula and ¹ H of the obtained compound
Table 1 shows the NMR data.

Example 4 2,3-dihydro-3,
Production of 3,4-trimethylbenzo [b] thiophene-5-carboxylic acid-1,1-dioxide 7-chloro-2,3-dihydro-3,3,3
Using 1.5 g (5.2 mmol) of 4-trimethylbenzo [b] thiophene-5-carboxylic acid-1,1-dioxide, 9.8 ml (16 mmol, 3.0 equivalents) and 0.3 g of 5% palladium carbon as a metal catalyst
Was added, and a hydrogen balloon was connected. Then, the pressure inside the reaction system was reduced to perform hydrogen replacement. Thereafter, the reaction was performed while stirring at 70 ° C. for 9 hours.

Then, the reaction mixture was cooled to room temperature,
% Palladium carbon was removed by filtration. The obtained filtrate was adjusted to pH 1 by adding 6 ml of concentrated hydrochloric acid, extracted twice with ethyl acetate, and the organic layer was washed with saturated saline.
Dry over anhydrous sodium sulfate. Further, by distilling off the solvent under reduced pressure, the desired 2,3-dihydro-3,
1.32 g of 3,4-trimethylbenzo [b] thiophene-5-carboxylic acid-1,1-dioxide (94% yield,
HPLC purity 94%). Table 1 shows the structural formula and ¹ H-NMR data of the obtained compound.

Example 5 2,3-dihydro-3,4
-Dimethylbenzo [b] thiophen-5-carboxylic acid-
Production of 1,1-dioxide In an autoclave, 7-chloro-2,3-
Dihydro-3,4-dimethylbenzo [b] thiophene-
2.1 g of 5-carboxylic acid-1,1-dioxide (7.6 g)
Mmol), and 14 ml (39 mmol, 5 mmol) of a 10% by weight aqueous sodium hydroxide solution.
1 equivalent), and 0.42 g of 5% palladium carbon was added as a metal catalyst. Then, the inside of the reaction system was pressurized to perform nitrogen replacement three times and hydrogen replacement three times, and then pressurized to 0.4 MPa with hydrogen, and then reacted by stirring at 70 ° C. for 9 hours.

Next, the obtained reaction mixture was cooled to room temperature, and 5% palladium carbon was removed by filtration. The obtained filtrate was adjusted to pH 1 with 8 ml of concentrated hydrochloric acid, extracted twice with ethyl acetate, and the organic layer was washed with saturated saline and dried over anhydrous sodium sulfate. Furthermore, 2,3-dihydro-3,
1.84 g of 4-dimethylbenzo [b] thiophen-5-carboxylic acid-1,1-dioxide (98% yield, HPL
C purity 97%). Structural formula of the obtained compound and
Table 1 shows the ¹ H-NMR data.

Example 6 4-methoxyimino-5
Production of methylthiochroman-6-carboxylic acid-1,1-dioxide In Example 5, 7-chloro-2,
Instead of 3-dihydro-3,4-dimethylbenzo [b] thiophene-5-carboxylic acid-1,1-dioxide, 8
-Chloro-4-methoxyimino-5-methylthiochroman-6-carboxylic acid-1,1-dioxide was used, and the reaction temperature was changed to 60 ° C.
4-methoxyimino-5-methylthiochroman-6-carboxylic acid-1,1-dioxide was obtained in a yield of 66%. The structural formula and ¹ H-NMR data of the obtained compound were
It is shown in the table.

[0065]

[Table 1]

[0066]

Industrial Applicability According to the present invention, thiochroman-6-carboxylic acid derivatives and dihydrobenzo [b] thiophen-5- highly useful as intermediates for producing pyrazole derivatives and cyclohexanedione derivatives as active ingredients of herbicides. It is possible to provide a method for producing a carboxylic acid derivative which has a small environmental load and can keep production costs low.

Claims (2)

[Claims] 1. A compound represented by the general formula [1]: [Wherein, R ¹ represents a halogen atom or an alkyl group having 1 to 4 carbon atoms, and R ² , R ³ , R ⁴ and R ⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. X
Represents a chlorine atom, a bromine atom or an iodine atom, and n
Represents 1 or 0. Z ¹ is a group represented by the general formula [2], (Wherein, R ⁶ and R ⁷ each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, and R ⁶ and R ⁷ each independently represent When an alkyl group having 1 to 4 carbon atoms or both alkoxy groups having 1 to 4 carbon atoms, R ⁶ and R ⁷ are bonded to each other on an arbitrary carbon atom to form a spiro-type 3- to 7-membered ring. May be formed.). Wherein the halide represented by the general formula [3] is reduced using zinc in an aqueous alkali solution. [Wherein, R ¹ represents a halogen atom or an alkyl group having 1 to 4 carbon atoms, and R ² , R ³ , R ⁴ and R ⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. And n
Represents 1 or 0. Z ¹ is a group represented by the general formula [2]: (Wherein, R ⁶ and R ⁷ each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, and R ⁶ and R ⁷ each independently represent When an alkyl group having 1 to 4 carbon atoms or both alkoxy groups having 1 to 4 carbon atoms, R ⁶ and R ⁷ are bonded to each other on an arbitrary carbon atom to form a spiro-type 3- to 7-membered ring. May be formed.). The method for producing a thiochroman-6-carboxylic acid derivative or a dihydrobenzo [b] thiophen-5-carboxylic acid derivative represented by the following formula: 2. A compound of the general formula [4] [Wherein, R ¹ represents a halogen atom or an alkyl group having 1 to 4 carbon atoms, and R ² , R ³ , R ⁴ and R ⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. X
Represents a chlorine atom, a bromine atom or an iodine atom, and n
Represents 1 or 0. Z ² is a group represented by the general formula [5] or [6], (Wherein, R ⁸ and R ⁹ are shown each independently represent a hydrogen atom, an alkyl group, or R ⁸ and R ⁹ are both alkoxy groups having 1 to 4 carbon atoms having 1 to 4 carbon atoms. Further, R ⁸ and When R ⁹ is each independently an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, both R ⁶ and R 9
^{And 7} may be bonded to each other on arbitrary carbon atoms to form a spiro-type saturated hydrocarbon ring having a 3 to 7-membered ring structure or an oxygen-containing saturated hydrocarbon ring. R ¹⁰ represents an oxygen atom, a sulfur atom or an alkoxyimino group having 1 to 4 carbon atoms. ). Wherein the halide represented by the general formula [7] is reduced in an aqueous alkaline solution in the presence of a metal catalyst using hydrogen. [Wherein, R ¹ represents a halogen atom or an alkyl group having 1 to 4 carbon atoms, and R ² , R ³ , R ⁴ and R ⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. And n
Represents 1 or 0. Z ² is a group represented by the general formula [5] or [6], (Wherein, R ⁸ and R ⁹ are shown each independently represent a hydrogen atom, an alkyl group, or R ⁸ and R ⁹ are both alkoxy groups having 1 to 4 carbon atoms having 1 to 4 carbon atoms. Further, R ⁸ and When R ⁹ is each independently an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, both R ⁶ and R 9
^{And 7} may be bonded to each other on arbitrary carbon atoms to form a spiro-type saturated hydrocarbon ring having a 3 to 7-membered ring structure or an oxygen-containing saturated hydrocarbon ring. R ¹⁰ represents an oxygen atom, a sulfur atom or an alkoxyimino group having 1 to 4 carbon atoms. ). The method for producing a thiochroman-6-carboxylic acid derivative or a dihydrobenzo [b] thiophen-5-carboxylic acid derivative represented by the following formula: