JPH11302233A - Fluorine-containing aniline compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new compound useful as an intermediate for agrochemicals and chemicals, etc., especially agricultural and horticultural insecticides, etc. SOLUTION: This compound is represented by formula I (R<1> is a halogen, a 1-6C alkyl, a 1-6C alkoxy or the like; R<2> to R<4> are each H or a 2-6C perfluoroalkyl, with the proviso that R<4> is pentafluoroethyl or the like when R<1> is F atom and R<2> and R<3> are each H), e.g. 2-methyl-4-pentafluoroethylaniline. Furthermore, the compound represented by formula I is preferably obtained by reacting an aniline derivative represented by formula II (X1 , X2 and X3 are each H, I or Br, with the proviso that X1 , X2 and X3 are not simultaneously H) with a perfluoroalkyl iodide such as R<2> -I in the presence of an activated copper powder and an inert solvent such as N,N-dimethylformamide at a reactional temperature within the range of ambient temperature to 200 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a novel fluorine-containing aniline compound which is useful as an intermediate for pharmaceuticals, agricultural chemicals, chemicals and the like, and which has not been described in the literature, and particularly relates to Japanese Patent Application No. 9-339393.
It is a compound useful as a raw material compound for agricultural and horticultural insecticides filed as No.

[0002]

2. Description of the Related Art JP-A-63-99046 and JP-A-6-1840065 disclose that anilines similar to the fluorine-containing aniline compound of the present invention are useful as intermediates of benzoylurea-based insecticides. Are listed.

[0003]

The present invention provides a compound represented by the general formula (I):

Embedded image (Wherein R ¹ is a halogen atom, a C ₁ -C ₆ alkyl group, a C ₁ -C ₆
Represents an alkoxy group or a trifluoromethyl group, R ² ,
R ³ and R ⁴ represent a hydrogen atom or a C ₂ -C ₆ perfluoroalkyl group. However, when R ² , R ³ and R ⁴ do not simultaneously represent a hydrogen atom, R ¹ represents a fluorine atom, and R ² and R ⁴ represent a hydrogen atom, R ³ represents a pentafluoroethyl group or n- Excluding heptafluoropropyl group. )).

[0004]

BEST MODE FOR CARRYING OUT THE INVENTION The fluorine-containing aniline compound of the present invention can be produced, for example, by the following production method.

[0005] Manufacturing method

Embedded image (In the formula, X ¹ , X ² and X ³ represent a hydrogen atom, an iodine atom or a bromine atom. However, X ¹ , X ² and X ³ do not represent a hydrogen atom at the same time. R ¹ , R ² , R ³ and R ⁴ are the same as above.)

An aniline derivative represented by the general formula (II) is converted into a compound represented by the general formula (III) in the presence of an active copper powder and an inert solvent.
By reacting with a perfluoroalkyl iodide represented by the general formula (IV) or (V), a fluorine-containing aniline compound represented by the general formula (I) can be produced. The amount of the perfluoroalkyl iodide represented by the general formula (III), (IV) or (V) and the amount of active copper powder used is usually 1 to 5 times the amount of the aniline derivative represented by the general formula (II). May be used by appropriately selecting from the range. The inert solvent used in this reaction may be any inert solvent that does not significantly inhibit the progress of this reaction, and examples thereof include aprotic polar solvents such as N, N-dimethylformamide (DMF) and dimethylsulfoxide (DMSO). Can be used. The reaction temperature can be appropriately set within a range from room temperature to 200 ° C.
After completion of the reaction, it may be isolated from the reaction system containing the target substance by a conventional method, and if necessary, purified by a method such as silica gel chromatography, distillation, or recrystallization. This reaction is described in Bull. Chem. Soc. Jpn. ,
65 , 2141 to 2144 (1992).

Manufacturing method 2.

Embedded image (In the formula, R ¹ , R ² , R ³ , R ⁴ , X ¹ , X ² and X ³ are the same as described above, and R ⁵ represents a protecting group such as an acyl group.)

The acylaniline derivative represented by the general formula (VI) is prepared by reacting the acylaniline derivative represented by the general formula (I) in the presence of an active copper powder and an inert solvent.
II), by reacting with a perfluoroalkyl iodide represented by the general formula (IV) or (V) to obtain an acylaniline derivative represented by the general formula (VII), and the acylaniline derivative (VI
By isolating or de-acylating I), the fluorine-containing aniline compound represented by the general formula (I) can be produced. General formula (VI) → General formula (VII) This reaction can be produced according to Production method 1. . General formula (VII) → General formula (I) This reaction is usually carried out under acidic conditions. As the acid, for example, a mineral acid aqueous solution such as a 5-35% hydrochloric acid aqueous solution is used. Alcohols, such as
An inert solvent such as tetrahydrofuran (THF) and acetonitrile can be used in combination. The reaction can be performed at a temperature ranging from room temperature to the boiling point of the solvent used. The target product can be produced by post-processing in the same manner as in Production Method 1.

Manufacturing method 3.

Embedded image (Wherein, R ¹ , R ² , R ³ , R ⁴ , X ¹ , X ² and X ³ are the same as above.)

The nitrobenzene derivative represented by the general formula (VIII) is converted to a compound represented by the general formula (IV) in the presence of an active copper powder and an inert solvent.
(III), a nitrobenzene derivative represented by the general formula (IX) by reacting with a perfluoroalkyl iodide represented by the general formula (IV) or (V), and the nitrobenzene derivative (IX)
Can be isolated or subjected to a reduction reaction without isolation to produce a fluorine-containing aniline compound represented by the general formula (I). General formula (VIII) → General formula (IX) This reaction can be produced according to Production method 1. . General formula (IX) → General formula (I) The reduction reaction is usually carried out by catalytic hydrogenation in the presence of a catalyst such as 5% palladium carbon at a weight ratio of 1 to 5% in an alcohol solvent, or a solvent such as ethanol. The target substance can be produced by reducing the medium with an aqueous solution of stannous chloride in hydrochloric acid. This reaction is described in The Chemical Society of Japan, 1973, 235
It can be produced according to the method described in 1.

The typical examples of the fluorine-containing aniline compound represented by the general formula (I) of the present invention are shown in Table 1 below, but the present invention is not limited thereto. "I" in the table below
Represents iso. General formula (I)

Embedded image

[0012]

[Table 1]

[0013]

[Table 2]

[0014]

The present invention will now be described by way of representative examples and reference examples, but the present invention is not limited thereto. Example 1.2 Preparation of 2-methyl-4-pentafluoroethylaniline (Compound No. 3).

Embedded image 11.7 g of 2-methyl-4-iodoaniline (0.05
Mol), copper powder 6.4 g, iodopentafluoroethane 1
8.5 g and 100 ml of DMSO were put in an autoclave, and the reaction was carried out with stirring for 6 hours while keeping the internal temperature at 120 ° C. After completion of the reaction, the reaction solution is returned to room temperature, and ice water 500
After stirring sufficiently, insoluble materials were removed, and the desired product was extracted with 300 ml of ethyl acetate. Wash the extract with water,
After drying over anhydrous sodium sulfate and concentration, the residue was purified by distillation under reduced pressure to obtain 9.8 g of the desired product. Physical properties: b. p. 95-105 ° C / 10 mmHg Yield: 87%

Embodiment 2 FIG. Preparation of 2-1.2-ethyl-4-pentafluoroethylacetanilide.

Embedded image 4.0 g of 2-ethyl-4-iodoacetanilide (0.
0138 mol), 1.8 g of copper powder, 5.1 g of iodopentafluoroethane and 40 ml of DMSO were placed in an autoclave, and the reaction was carried out with stirring for 6 hours while maintaining the internal temperature at 120 ° C. After completion of the reaction, the reaction solution is returned to room temperature, and ice water 2
After the mixture was poured into 00 ml and stirred sufficiently, the insoluble matter was removed, and the desired product was extracted with 200 ml of ethyl acetate. The extract was washed with water, dried over anhydrous sodium sulfate, concentrated, and the residue was purified by silica gel column chromatography to obtain 0.7 g (yield: 18%) of the desired product.

2-2-2 Preparation of 2-ethyl-4-pentafluoroethylaniline (Compound No. 18)

Embedded image 0.6 g (2.1 mmol) of 2-ethyl-4-pentafluoroethylacetanilide in 10 ml of 6N hydrochloric acid aqueous solution
And the reaction was carried out under reflux for 2 hours. After completion of the reaction, the reaction solution was ice-cooled, neutralized with a 10% aqueous sodium hydroxide solution, and the desired product was extracted with ethyl acetate. The extract was washed with water, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to obtain 0.4 g of the desired product. Physical properties: ¹ H-NMR (δ, ppm): 1.29 (t.3H), 2.52 (q.2H), 3.95 (br.2H), 6.8 (d.1H), 7.2-7.26 (m.2H). Rate: 80%

Example 3 Preparation of 2-chloro-4-pentafluoroethylaniline (Compound No. 11)

Embedded image 5.0 g (19.7 mmol) of 2-chloro-4-iodoaniline, 2.8 g of copper powder, 10.0 g of iodopentafluoroethane and 50 ml of DMF were put in an autoclave, and the mixture was stirred for 20 hours while maintaining the internal temperature at 135 ° C. The reaction was performed. After completion of the reaction, the reaction solution is returned to room temperature, and ice water 20
After pouring the mixture into 0 ml and thoroughly stirring, the insoluble matter was removed, and the target substance was extracted with 200 ml of ethyl acetate. The extract was washed with water, dried over anhydrous sodium sulfate, concentrated, and the residue was purified by silica gel column chromatography to obtain 4.2 g of the desired product. Physical properties: ¹ H-NMR (δ, ppm): 4.4 (br.2H), 6.8 (d.1H), 7.27 (dd.1H), 7.47 (d.1H). Yield: 87%

EXAMPLE 4.2 2-trifluoromethyl-4-
Production of pentafluoroethylaniline (Compound No. 22).

Embedded image 6.0 g of 2-trifluoro-4-iodoaniline (2
0.9 mol), 2.8 g of copper powder, 11.1 g of iodopentafluoroethane and 40 ml of DMF were placed in an autoclave, and the reaction was carried out with stirring for 7 hours while keeping the internal temperature at 135 ° C. After completion of the reaction, the reaction solution is returned to room temperature, and ice water 20
After pouring the mixture into 0 ml and thoroughly stirring, the insoluble matter was removed, and the target substance was extracted with 200 ml of ethyl acetate. The extract was washed with water, dried over anhydrous sodium sulfate, concentrated, and the residue was purified by silica gel column chromatography to obtain 3.9 g of the desired product. Physical properties: ¹ H-NMR (δ, ppm): 4.52 (br. 2 H), 6.81 (d, 1 H), 7.27 (dd. 1 H), 7.48 (d. 1 H), 7.63 (br, 1 H). Yield: 67%

Embodiment 5 FIG. 5-1.2-methyl-4- (heptafluoropropane-
Production of 2-yl) nitrobenzene.

Embedded image 12.0 g of 4-iodo-2-methylnitrobenzene
(0.0456 mol), 11.6 g of copper powder, 40 g of 2-iodoheptafluoropropane and 200 ml of DMF were placed in an autoclave, and the reaction was carried out with stirring for 6 hours while keeping the internal temperature at 140 ° C. After the reaction was completed, the reaction solution was returned to room temperature, poured into ice water (600 ml), and sufficiently stirred. After removing insolubles, the target substance was extracted with hexane (300 ml). The extract was washed with water, dried over anhydrous sodium sulfate, and concentrated.
Purification was performed by distillation under reduced pressure to obtain 11.4 g of the desired product. Physical properties: b. p. 120-125 / 10 mmHg Yield: 82%

5.2.2 Preparation of 2-methyl-4- (heptafluoropropan-2-yl) aniline (Compound No. 4)

Embedded image 11.4 g (0.0374 mol) of 2-methyl-4- (heptafluoropropan-2-yl) nitrobenzene was dissolved in 60 ml of ethanol, and hydrochloric acid was added to the solution under ice cooling.
A solution in which 29.5 g of SnCl ₂ .2H ₂ O was dissolved in 0 ml was added dropwise over 30 minutes. After completion of the dropwise addition, the reaction was performed at room temperature for 2 hours. After completion of the reaction, add 200 ml of ice water to the reaction solution.
The solution was neutralized by adding a 40% aqueous sodium hydroxide solution under ice-cooling, and then a 40% aqueous sodium hydroxide solution was added until a homogeneous solution was obtained, and the desired product was extracted with 100 ml of ether. The extract was washed with water, dried over anhydrous sodium sulfate, concentrated and purified by distillation under reduced pressure to obtain 9.8 g of the desired product
I got Physical properties: b. p. 100-110 / 10 mmHg Yield: 95%

Reference Example 1.3 Production of 3-bromo-N ^1- (4-nonafluorobutyl-2-methylphenyl) -N ² -isopropyl-phthalic diamide (hereinafter referred to as reference compound). 0.54 g of 6-bromo-N-isopropyl-phthalic acid isoimide was dissolved in 10 ml of tetrahydrofuran, 0.65 g of 4-nonafluorobutyl-2-methylaniline was added to the solution, and the reaction was carried out with stirring for 1 hour.
After completion of the reaction, the solvent of the reaction solution was distilled off under reduced pressure, and the obtained residue was washed with ether-n-hexane to obtain a residue.
1.1 g of the desired product was obtained. Physical properties: m. p. 190-191 ° C, 94% yield

Reference Example 2 Diamondback moth (Plutella xylostella)
Insecticidal test against Chinese cabbage seedlings was released to adult Chinese moths and laid eggs. Two days after release, Chinese cabbage seedlings with spawning eggs were added to a drug solution diluted to 500 ppm with a drug containing a reference compound as an active ingredient. It was immersed for 30 seconds, air-dried, and allowed to stand in a constant temperature room at 25 ° C. Six days after the immersion in the drug solution, the number of hatching insects was investigated, the mortality was calculated by the following equation, and the judgment was made according to the following criteria.
One ward three consecutive system

(Equation 1) As a result, the reference compound showed 100% mortality.

Reference Example 3 Spodoptera l
Insecticidal test on itura) Cabbage leaf pieces (variety: four seasons harvest) were immersed in a chemical solution diluted to 500 ppm with a drug containing a reference compound as an active ingredient for about 30 seconds, air-dried, and then placed in a plastic petri dish with a diameter of 9 cm covered with wet filter paper. After inoculating the third instar larvae of the cutworm, Spodoptera litura, they were allowed to stand in a constant temperature room at 25 ° C. and 70% humidity. Four days after the inoculation, the number of live and dead insects was examined, and the mortality was calculated according to Reference Example 2. As a result, the reference compound showed a mortality rate of 100%.

Claims (4)

[Claims] 1. A compound of the general formula (I) (Wherein R ¹ is a halogen atom, a C ₁ -C ₆ alkyl group, a C ₁ -C ₆
Represents an alkoxy group or a trifluoromethyl group, R ² ,
R ³ and R ⁴ represent a hydrogen atom or a C ₂ -C ₆ perfluoroalkyl group. However, when R ² , R ³ and R ⁴ do not simultaneously represent a hydrogen atom, R ¹ represents a fluorine atom, and R ² and R ⁴ represent a hydrogen atom, R ³ represents a pentafluoroethyl group or n- Excluding heptafluoropropyl group. A) a fluorine-containing aniline compound represented by the formula: 2. The fluorine-containing aniline compound according to claim _{1, wherein} R ¹ is a C ₁ -C ₆ alkyl group. 3. The fluorine-containing aniline compound according to claim 1, wherein R ¹ is a chlorine atom or a bromine atom. 4. The fluorine-containing aniline compound according to claim 1, wherein R ¹ represents a fluorine atom, R ² and R ⁴ represent a hydrogen atom, and R ³ represents a heptafluoropropan-2-yl group.