JPH07188140A - Production of phenoxybenzoylformic acid amide - Google Patents

Abstract

PURPOSE:To provide an industrially highly valuable method for producing a phenoxybenzoylformic acid amide useful as a production intermediate for agrochemicals, medicines, dyestuffs, etc. CONSTITUTION:A phenoxybenzoylnitrile compound as a raw material is reacted in the presence of a small amount of water in an ether solvent containing hydrogen chloride and subsequently hydrolyzed to obtain the objective phenoxybenzoylformic acid amide in a high yield and in a high selectivity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing phenoxybenzoylformic acid amides which are useful as intermediates for the production of agricultural drugs, dyes and the like. More specifically, it relates to an improved process for producing phenoxybenzoylformamides, which comprises reacting phenoxybenzoylnitriles with hydrogen chloride in the presence of a small amount of water in an ether solvent, followed by hydrolysis.

[0002]

2. Description of the Related Art Conventionally, as a method of hydrolyzing nitriles to obtain amides, a method of hydrolyzing sodium hydroxide in a tert-butanol solvent [J. Or
g. Chem. , 41 , 3769 (1976)], or a method of using hydrogen peroxide to lead to an amide in the presence of sodium carbonate [Helv. , 39 , 1233 (1956)]
Such methods are known. However, when phenoxybenzoyl nitrites are exposed to such an alkaline aqueous solution, there is a problem that the target phenoxybenzoylformic acid amide cannot be obtained because the phenoxybenzoyl nitrites are rapidly hydrolyzed to phenoxybenzoic acids.

Further, a method of reacting under acidic conditions, for example, a method of hydrolyzing benzoyl nitrites in concentrated hydrochloric acid as a method of leading to benzoyl formate amide [Can.
J. Chem. , 49 , 919 (1971)], 85%
A method of obtaining amides by hydrolyzing sodium bromide in sulfuric acid as a catalyst [Tetrahedron lett. ，
1980, 21 (37), 3539] and the like are known. However, even in these methods, when applied to phenoxybenzoylnitriles, there is a problem that the target amide compound is hardly obtained, and phenoxybenzoic acid is obtained as a main product, and these methods are preferable methods. is not. Therefore, a method capable of efficiently converting phenoxybenzoylnitriles into phenoxybenzoylformamides has not been found yet.

[0004]

The object of the present invention is to solve the above-mentioned problems of the prior art, and phenoxybenzoylformic acid useful as an intermediate for the production of agricultural drugs, dyes and the like. It is an object of the present invention to provide an improved and more industrial process for producing amides.

[0005]

Means for Solving the Problems As a result of intensive studies to solve the problems of the prior art, the present inventors have found that when phenoxybenzoylnitriles are hydrolyzed into amides, they are phenoxybenzoylnitriles. It has been found that a good method is to react the compounds in an ether solvent in which hydrogen chloride is dissolved to form a chlorimino body, and then to react with water to hydrolyze the chlorimino body to form an amide body. At this time, it was found that the coexistence of a lower alcohol in the reaction solution improves the reaction rate and the conversion rate. However, there is a problem that phenoxybenzoic acid alkyl ester and benzoylformic acid alkyl ester are by-produced under the condition that alcohol coexists.

In the present reaction, the present inventors proceeded in the same manner even if the lower alcohol was replaced with a small amount of water, and the benzoylformic acid alkyl ester was not produced as a by-product in a high yield and a high selectivity. The present invention has been completed by finding that the desired phenoxybenzoylformic acid amides can be obtained.

That is, according to the present invention, in converting phenoxybenzoylnitriles into phenoxybenzoylformamides, phenoxybenzoylnitriles are reacted with hydrogen chloride in the presence of a small amount of water in an ether solvent and then hydrolyzed. And a method for producing phenoxybenzoylformic acid amides. The method of the present invention is an industrially applicable excellent method. According to the method of the present invention, it is possible to obtain phenoxybenzoylformic acid amides with high yield and high selectivity. Further, phenoxybenzoic acid, which is a by-product during the reaction, can be used again as a raw material for phenoxybenzoylnitrile, which is a raw material, which is an industrially efficient production method.

Further, in the method of the present invention, in order to isolate the desired product after the reaction, water is added to the reaction mixture and the mixture is extracted with an organic solvent. After that, a simple operation of distilling off the solvent is sufficient. At this time, by adjusting the pH of the alkaline washing water with a mineral acid such as hydrochloric acid, the phenoxybenzoic acid produced as a by-product can be easily collected by filtration as crystals.
The phenoxybenzoylformic acid amides obtained by the method of the present invention have a quality that can be sufficiently utilized as an intermediate for the production of agricultural drugs, dyes and the like.

The method of the present invention will be described below. The phenoxybenzoyl nitriles used in the method of the present invention are
A benzoylnitrile substituted by an alkyl group, an alkoxy group or a phenoxy group substituted by a halogen or an unsubstituted phenoxybenzoylnitrile. Specifically, 2-phenoxybenzoyl nitrile, 2
-(4-methylphenoxy) benzoylnitrile, 2-
(3-methylphenoxy) benzoyl nitrile, 2-
(3,4-dimethylphenoxy) benzoyl nitrile,
2- (4-ethylphenoxy) benzoyl nitrile, 2
-(3-Ethylphenoxy) benzoyl nitrile, 2-
(3,4-diethylphenoxy) benzoyl nitrile,
2- (4-methoxyphenoxy) benzoyl nitrile,
2- (3-methoxyphenoxy) benzoyl nitrile,
2- (3,4-dimethoxyphenoxy) benzoylnitrile, 2- (4-chlorophenoxy) benzoylnitrile, 2- (4-bromophenoxy) benzoylnitrile, 2- (3-chlorophenoxy) benzoylnitrile, 2- (3 , 4-dichlorophenoxy) benzoyl nitrile and the like. However, as long as it is a phenoxybenzoinitrile, it is not limited by the compounds listed here.

The ether solvent used for the reaction with phenoxybenzoyl nitriles is diethyl ether, di-n.
-Propyl ether, diisopropyl ether, di-n
-Butyl ether, tetrahydrofuran or 1,4-
Examples include dioxane. However, it is not limited as long as it is an ether solvent. There is no particular limitation on the amount of these ether solvents used. Usually, the amount of phenoxybenzoyl nitrile is 1 times or more by weight,
It is preferably used in an amount of 2 times by weight or more.

Further, hydrogen chloride is 0.1 equivalent or more, preferably 0.2 equivalent or more with respect to the phenoxybenzoyl nitriles, and the concentration of hydrogen chloride in the ether solvent is 0.2.
It is used at a concentration above the specified level, preferably 1N to a saturated concentration. If the concentration and amount of hydrogen chloride are too low or too low, chlorinimilation of the nitrile is less likely to occur. Therefore, a certain concentration or more is required.

If the amount of water added to the reaction system is too small, the conversion will not be improved, and if it is too large, a large amount of phenoxybenzoic acid will be easily produced as a by-product, so that the amount of water usually added to the raw material phenoxybenzoylnitriles is 0. .About.1 to 20% by weight is preferable, and more preferably 0.5 to 10% by weight. The reaction temperature is suitably in the range of 0 ° C. to the boiling point of the ether solvent used. The range of 10 ° C. to the boiling point of the ether solvent is preferable.

The hydrolysis carried out after the reaction with hydrogen chloride is carried out by adding water in an equimolar amount or more to the phenoxybenzoylnitrile as a raw material. The amount of water is not particularly limited as long as it is equimolar or more. The temperature at which water is added is not particularly limited, but is preferably in the range of 0 ° C to the boiling point of the ether solvent. The range of 0 to 50 ° C is more preferable. The reaction time is not uniquely determined by the raw material concentration and the reaction temperature, but in the reaction at room temperature, the reaction is usually completed within 5 days, and phenoxybenzoylformic acid amides can be obtained in high yield and high quality.

A specific embodiment of the method of the present invention is as follows. A predetermined amount of phenoxybenzoyl nitrites is added to an ether solvent in which a predetermined amount of hydrogen chloride is dissolved, and then a predetermined amount of water is added, followed by stirring at room temperature for a predetermined time to react. After that, a predetermined amount of water is added and stirred to hydrolyze. Here, the charging order of the raw material, catalyst, solvent and water is not limited to the above method. In the present invention, the progress of the reaction can be known using a means such as high performance liquid chromatography.

The phenoxybenzoylformic acid amides obtained by the method of the present invention are obtained after the reaction, after cooling the reaction mixture, if necessary, and after adding an organic solvent insoluble or sparingly soluble in water to the reaction solution for extraction. The organic phase can be isolated by a simple operation of subjecting the organic phase to alkali washing and water washing, then drying the organic phase with a desiccant and distilling off the solvent. In order to obtain higher-purity phenoxybenzoylformic acid amides, a method of purifying the phenoxybenzoylformic acid amides obtained by the above method by a purification means such as recrystallization using an appropriate solvent can be mentioned. Further, the phenoxybenzoic acid produced as a by-product can be easily isolated by an operation of adjusting the pH of the resulting alkaline washing liquid using a mineral acid such as hydrochloric acid during the isolation operation and collecting the precipitated phenoxybenzoic acid by filtration. . The phenoxybenzoic acid obtained by this operation can be sufficiently used as a raw material for the phenoxybenzoylnitrile which is the raw material of the present invention. The phenoxybenzoylformic acid amides obtained by the present invention have a quality that can be sufficiently used as an intermediate for the production of agricultural drugs, dyes and the like.

[0016]

EXAMPLES The present invention will be specifically described below with reference to examples.
However, the present invention is not limited to these examples. Example 1 A 100 ml round-bottomed flask was charged with 24 ml of 6N hydrochloric acid dioxane solution, then 5.4 g (24 mmol) of 2-phenoxybenzoylnitrile and 0.22 g (12 mmol) of water. The container was sealed and stirred at room temperature for 2 days. After cooling the reaction mixture with ice, water 50 m
1 was added and the mixture was stirred at room temperature for 30 minutes. The organic phase obtained by charging 50 g of toluene into the reaction solution and performing liquid separation and extraction was washed with 30 ml of a saturated aqueous solution of sodium hydrogen carbonate, and then with water.
It was washed with 0 g of water. After the organic phase was dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure to obtain 5.0 g of the desired 2-phenoxybenzoylformamide (purity conversion yield 85
%)Obtained. 6 including alkali cleaning solution and water cleaning solution
The pH was adjusted to 1 with N hydrochloric acid, and the precipitated crystals were collected by filtration to 0.7.
2 g (purity conversion yield 14%) of phenoxybenzoic acid was obtained.

[Examples 2 and 3 and Comparative Example 1] Example 2
3 and Comparative Example 1, the amount of water added was examined.
The other conditions were the same as in Example 1. The results are shown in Table 1.

[Table 1] ((w%) ^* : wt% relative to the raw material 2-phenoxybenzoylnitrile)

Comparative Example 2 In Comparative Example 2, water was changed to methanol. The other conditions were the same as in Example 1. The results are shown in Table 2.

[Table 2]

[Examples 4 to 7] The types of phenoxybenzoylnitriles used in the reaction in Examples 4 to 7 were examined. The other conditions were the same as in Example 1. The results are shown in Table 3.

[Table 3]

[0020]

According to the present invention, in converting phenoxybenzoyl nitrites to phenoxybenzoyl formate amides, they are efficiently reacted in an ether solvent in which hydrogen chloride is dissolved in the presence of a small amount of water, and then Phenoxybenzoylformic acid amides can be obtained by hydrolysis. The method of the present invention is an industrially applicable excellent method, and according to the method of the present invention, phenoxybenzoylformic acid amides can be obtained in a high yield and a high selectivity under relatively mild conditions. It is also possible to isolate the target compound after the reaction by a simple operation of distilling the solvent after washing the reaction mixture with water and the organic phase obtained by liquid separation with an organic solvent and washing with an alkali. it can. Therefore, the present invention is an industrially valuable method for producing phenoxybenzoylformic acid amides, which are production intermediates useful for agricultural medicine and dyes.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ryuichi Mita 30 Asamu-cho, Omuta-shi, Fukuoka Mitsui Toatsu Chemical Co., Ltd.

Claims (4)

[Claims] 1. A phenoxybenzoylnitrile compound
In a tellurium solvent, in the presence of a small amount of water, reacted with hydrogen chloride,
Then, the method for producing phenoxybenzoylformic acid amides is characterized by hydrolyzing. 2. The method according to claim 1, wherein the phenoxybenzoylnitriles are benzoylnitrile substituted by an alkyl group, an alkoxy group or a phenoxy group substituted by a halogen or an unsubstituted phenoxybenzoylnitrile. 3. The method according to claim 1, wherein the amount of water coexisted is 0.1 to 20% by weight based on the phenoxybenzoylnitriles. 4. The concentration of hydrochloric acid in the ether solvent is from 1N to
The method of claim 1, wherein the method is saturated.