JPH05320096A - Production of glycollic acids - Google Patents

Abstract

PURPOSE:To industrially and advantageously obtain a glycollic acid useful as an intermediate for agricultural chemicals, especially herbicides by reacting specific alpha-halogenoacetic acids with a specific carboxylic acid salt using a mixed solvent of methanol and water as a solvent. CONSTITUTION:An alpha-halogenoacetic acid expressed by formula I [X is chlorine or bromine; R1 and R2 are H or alkyl; R3 is the formula OR' (R' is alkyl) or the formula NR'' R''' (R'' and R''' are H, alkyl or aryl)] (e.g. N,N- methylphenyl-alpha-chloroacetic acid amide) is made to react with a carboxylic acid salt expressed by formula II (R is H or alkyl; M is alkali metal or alkaline earth metal) (e.g. sodium acetate) using a mixed solvent of methanol and water as a solvent at 67 deg.C for 22hr and then methanol is distilled off under reduced pressure and ethyl acetate and water are added to the residue and hydrochloric acid is dropped thereto to control pH to 4 and an organic layer is separated and the solvent is distilled off under reduced pressure to provide the objective glycollic acid expressed by formula III in ordinary reaction without using the catalyst.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a glycol acetic acid represented by the following general formula 3 by reacting an α-halogenoacetic acid represented by the following general formula 1 with a carboxylic acid salt represented by the general formula 2. The present invention relates to a method for producing a high yield.

[0002]

[Chemical 1] [In the above formula, X is chlorine or bromine, R ₁ and R ₂ are hydrogen or an alkyl group, R ₃ is OR ', or NR "R""
(R 'is an alkyl group, R''andR''' are hydrogen or an alkyl group or an aryl group). ]

[0003]

[Chemical 2] [However, in the above formula, R represents hydrogen or an alkyl group, and M represents an alkali metal or an alkaline earth metal. ]

[0004]

[Chemical 3] [However, in said formula, R <1> -R < ₃ > shows the same group as Formula _{1 and} Formula 2. ]

[0005]

Glycolacetic acids are useful as intermediates for agricultural chemicals, especially herbicides. Thus, as a method for producing the compound, a method for producing an acyloxyacetic acid represented by the following general formula 4 by hydrolysis is conventionally known.

[0006]

[Chemical 4] [However, in said formula, R <1> -R < ₃ >, R shows the group same as Formula _{1 and} Formula 2. ]

[0007]

However, since the industrially advantageous method for producing the acyloxyacetic acid has not been established, the glycol acetic acid which is the object of the present invention cannot be efficiently produced. That is, as a method for producing an acyloxyacetic acid, a method of reacting the above α-halogenoacetic acid with a carboxylic acid salt is conventionally known. However,
In such a method, in order to prevent the polymerization of the raw material α-halogenoacetic acid, a large amount of 4-5 times as much carboxylic acid salt is indispensable, and even if such preventive measures are taken, the yield of the target compound is increased. Is only about 70 to 80%. In the case of industrially producing acyloxyacetic acids, the above-mentioned yield is not always satisfactory, and it is naturally necessary to recover the unreacted carboxylic acid salt, which causes many problems.

[0008]

SUMMARY OF THE INVENTION However, the inventors of the present invention have found that a target product can be efficiently obtained by using a quaternary ammonium salt or a phosphonium salt as a catalyst as a solution to such a problem. First filed as 58-66133. However, as a result of further research conducted by the present inventor, when a mixed solvent of methanol and water is used in carrying out the reaction, the reaction proceeds to glycolacetic acid in one step extremely efficiently without using the catalyst. The surprising fact was discovered and the present invention was completed.

The α-halogenoacetic acids referred to in the present invention are represented by the following general formula 1.

[Chemical 1]

However, in the formula, X is chlorine or bromine, R ₁ ,
R ₂ is hydrogen or an alkyl group, R ₃ is OR ′ or NR ″
R '''(R' is an alkyl group, R '' and R '' are hydrogen or an alkyl group or an aryl group). The number of carbon atoms of the alkyl group in R _{1 to} R ₃ and R ′ to R ″ ″ is generally 1
However, the present invention is not limited thereto. Further, the aryl group may be a substituted aryl group substituted with chlorine, bromine or the like.

Specific examples of the compound having such a structure include α-halogenoacetic acid such as methyl α-chloro (or bromo) acetate, ethyl α-chloro (or bromo) acetate, and propyl α-chloro (or bromo) acetate. Alkyl ester of α-position further substituted with a methyl group, an ethyl group or the like at the α-position, and N-monomethyl-α-chloro (or bromine)
Acetamide, N-monoethyl-α-chloro (or bromo) acetic acid amide, N, N-dimethyl-α-chloro (or bromo) acetic acid amide, N, N-diethyl-α-chloro (or bromo) acetic acid amide, N , N-methylethyl-α
-Chloro (or bromo) acetic acid amide, N-monophenyl-α-chloro (or bromo) acetic acid amide, N, N-methylphenyl-α-chloro (or bromo) acetic acid amide,
N, N-ethylphenyl-α-chloro (or bromo) acetic acid amide, N, N-diphenyl-α-chloro (or bromo) acetic acid amide, N-monomethyl- (α-chloro (or bromo) -α-methyl) Acetamide, N-monomethyl-
(Α-chloro (or bromine) -α-dimethyl) acetic acid amide, N-monoethyl- (α-chloro (or bromine) -α
-Methyl) acetic acid amide, N-monoethyl- (α-chloro (or bromo) -α-dimethyl) acetic acid amide, N, N-
Dimethyl- (α-chloro (or bromine) -α-dimethyl) acetic acid amide, N-monomethyl- (α-chloro (or bromo) -α-diethyl) acetic acid amide, N-monoethyl- (α-chloro (or bromo)) -Α-diethyl) acetic acid amide, N, N-diethyl- (α-chloro (or bromine)
-Α-diethyl) acetic acid amide, N-monophenyl- (α
-Chlor (or bromo) -α-methyl) acetic acid amide, N
-Monophenyl- (α-chloro (or bromine) -α-dimethyl) acetic acid amide, N-monophenyl- (α-chloro (or bromo) -α-ethyl) acetic acid amide, N-monophenyl- (α-chloro) (Or bromine) -α-diethyl)
Acetamide, N, N-methylphenyl- (α-chloro (or bromine) -α-dimethyl) acetic acid amide, N, N-
Methylphenyl- (α-chloro (or bromo) -α-diethyl) acetic acid amide, N, N-ethylphenyl- (α-
Chloro (or bromo) -α-dimethyl) acetic acid amide,
N, N-ethylphenyl- (α-chloro (or bromine)
-Α-diethyl) acetic acid amide, N, N-diphenyl-
(Α-chloro (or bromine) -α-dimethyl) acetic acid amide, N, N-diphenyl- (α-chloro (or bromine)
Examples include α-halogenoacetic acid derivatives such as -α-diethyl) acetic acid amide.

The carboxylic acid salt to be reacted with the α-halogenoacetic acid is represented by the following general formula. RCO
However, in the formula, R represents hydrogen or an alkyl group, and M represents an alkali metal or an alkaline earth metal. The alkyl group in R usually has 1 to 5 carbon atoms. As the alkali metal or alkaline earth metal, sodium, potassium, calcium, magnesium or the like is generally used, and the alkali metal is particularly preferably used.

Specific examples of the compound having such a structure include alkali metal salts or alkaline earth metal salts of formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid and the like. Most practical.
Such a carboxylic acid salt is usually used in a proportion of 1 to 2 mol based on the α-halogenoacetic acid. The most important feature of the present invention is that the reaction of the α-halogenoacetic acid and the carboxylate is carried out in a mixed solvent of methanol and water.

The mixing ratio of methanol and water is (9 by weight).
8: 2) to (60:40), preferably (95: 5) to
(75:25). When the amount of water is less than the above blending ratio, the acyloxyacetic acid component is present, and a step of re-hydrolyzing later is required, which is not practical. If the blending ratio of water exceeds the above range, the yield of the target product decreases, which is not preferable. By using such a mixed solvent of methanol and water, as described above, the amount of the carboxylic acid can be reduced without using a catalyst, and the generation of by-products due to the polymerization of α-halogenoacetic acids is prevented. As a result, the desired glycol acetic acid can be efficiently obtained in a high yield. Of course, if necessary, a catalyst such as a quaternary ammonium salt or a phosphonium salt may be used.

In carrying out the method of the present invention, there is no particular problem as long as the reaction temperature is not higher than the boiling point of the above-mentioned compound (α-halogenoacetic acid, carboxylic acid salt), usually 0 to 200 ° C., more preferably 20 to 120 Good results are obtained in the range of ° C. The reaction time cannot be limited because it depends on the type of compound, solvent, etc. used, but usually 0.5-2
It ends in 4 hours. The reaction solution is filtered, washed, if necessary,
After treatment such as dehydration and the like, the solvent is distilled off under reduced pressure to obtain glycol acetic acid represented by the following general formula 3, which is the object of the present invention.

[0016]

[Chemical 3] However, in the formula, R _{1 to} R ₃ correspond to the aforementioned α-halogenoacetic acid and carboxylic acid salt. Further, if necessary, it can be purified by a known method such as recrystallization.

Representative examples of such glycolic acids include methyl glycolate, ethyl glycolate,
Propyl glycolate, N-monomethyl-glycolic acid amide, N-monoethyl-glycolic acid amide, N, N
-Dimethyl-glycolic acid amide, N, N-diethyl-
Glycolic acid amide, N, N-methylethyl-glycolic acid amide, N-monophenyl-glycolic acid amide,
N, N-methylphenyl-glycolic acid amide, N, N-
Ethylphenyl-glycolic acid amide, N, N-diphenyl-glycolic acid amide, N-monomethyl-α-methylglycolic acid amide, N-monomethyl-α-dimethylglycolic acid amide, N-monoethyl-α-methylglycolic acid amide, N-monoethyl-α-dimethylglycolamide, N, N-dimethyl-α-dimethylglycolamide, N-monomethyl-α-ethylglycolamide, N-monomethyl-α-diethylglycolamide, N-monoethyl- α-Ethylglycolamide, N-monoethyl-α-diethylglycolamide, N, N-diethyl-α-diethylglycolamide, N-monophenyl-α-methylglycolamide, N-monophenyl-α- Dimethylglycolamide, N-monophenyl-α-ethyl Licolic acid amide, N-monophenyl-α-diethylglycolamide, N, N-methylphenyl-α-dimethylglycolamide, N, N-methylphenyl-α-diethylglycolamide, N, N-ethyl Phenyl-α-dimethylglycolamide, N, N-ethylphenyl-α
-Diethylglycolamide, N, N-diphenyl-
Examples include α-dimethyl glycolic acid amide and N, N-diphenyl-α-diethyl glycolic acid amide. The glycol acetic acid thus obtained is useful as an intermediate for various agricultural chemicals, pharmaceuticals and the like.

[0018]

[Operation] The mixed solvent of methanol and water used in the method for producing glycol acetic acid of the present invention can produce a desired glycol acetic acid in a high yield in a one-step reaction without using a catalyst. Has the effect of.

[0019]

The present invention will be described in more detail with reference to the following examples. Example 3 3.673 g (0.02 mol) of N, N-methylphenyl-α-chloroacetic acid amide and 1.804 g (0.022 mol) of sodium acetate were added to a mixed solvent of 20 ml of methanol and 5.6 ml of water. The reaction was carried out at 67 ° C for 22 hours. After the reaction was completed, methanol was distilled off under reduced pressure,
100 ml of ethyl acetate and 50 ml of water were added to the residue, and hydrochloric acid was added dropwise with stirring to adjust the pH to 4.

After standing, the ethyl acetate layer and the aqueous layer were separated, and the aqueous layer was extracted twice with 50 ml of ethyl acetate in total to combine with the ethyl acetate layer. The ethyl acetate layer was washed with 20 ml of a 1N aqueous hydrochloric acid solution, then neutralized with saturated aqueous sodium carbonate, and 2
It was washed twice with 0 ml of water. The ethyl acetate was distilled off under reduced pressure to obtain 3.07 g of white (colorless) crystals. The crystals had a melting point of 49 to 50 ° C. and were analyzed by NMR. The following results were obtained, and it was confirmed that the crystals were N, N-methylphenylglycolic acid amide. The yield of the compound based on N, N-methylphenyl-α-chloroacetic acid amide was 9
It was 4.0 mol%. NMR spectrum (δ pp
m, in CDCl ₃ )

[0021]

[Chemical 5]

(A): 3.5 (d: 1
H) (b): 3.37 (s: 3H) (c):
3.87 (d: 2H) (d): 7.1-7.
7 (m: 5H)

[0023]

INDUSTRIAL APPLICABILITY The method for producing glycol acetic acid according to the present invention uses a mixed solvent of methanol and water to obtain α
-Half-acetic acid and carboxylic acid salt have the effect that the desired glycol acetic acid can be produced in a high yield in a single step reaction without using a catalyst.

Claims (1)

[Claims] 1. To produce a glycol acetic acid represented by the following general formula 3 by reacting an α-halogenoacetic acid represented by the following general formula 1 with a carboxylic acid salt represented by the following general formula 2, A method for producing glycol acetic acid, which comprises using a mixed solvent of methanol and water as a solvent. [Chemical 1] [In the above formula, X is chlorine or bromine, R ₁ and R ₂ are hydrogen or an alkyl group, R ₃ is OR ', or NR "R""
(R 'is an alkyl group, R''andR''' are hydrogen or an alkyl group or an aryl group). ] [Chemical 2] [However, in the above formula, R represents hydrogen or an alkyl group, and M represents an alkali metal or an alkaline earth metal. ] [Chemical 3] [However, in the above formula, R ₁ , R ₂ and R ₃ represent the same groups as those in formulas ₁ and ₂ . ]