CN-109651190-B - Synthesis method of kresoxim-methyl

CN109651190BCN 109651190 BCN109651190 BCN 109651190BCN-109651190-B

Abstract

The invention belongs to the technical field of fine chemical industry, relates to a pesticide chemical synthesis technology, and in particular relates to a method for synthesizing kresoxim-methyl. The method takes 2- (2-methyl phenoxymethyl) benzoyl cyanide as a starting material, reacts with methoxyamine hydrochloride, and then introduces hydrochloric acid gas into a system after the reaction is finished.

Inventors

WANG SHUAISHUAI
CHENG DAOQUAN
WEI NENGCHUN
ZHANG YAOZHONG

Assignees

山东京博农化科技股份有限公司
京博农化科技有限公司

Dates

Publication Date: 20260421
Application Date: 20181228
Priority Date: 20181228

Claims (6)

1. A synthetic method of kresoxim-methyl is characterized in that 2- (2-methyl phenoxymethyl) benzoyl cyanide and methoxyamine hydrochloride are taken as raw materials, 2-methoxyimino-2- [2- (2-methyl phenoxymethyl) phenyl ] acetonitrile is obtained through oximation reaction, and then hydrochloric acid gas is introduced to perform pinner reaction to obtain kresoxim-methyl; The method comprises the following specific steps: (1) Adding 2- (2-methyl phenoxymethyl) benzoyl cyanide and methoxyamine hydrochloride into methanol, adding a catalyst, heating to 55-65 ℃, and preserving heat until the reaction is complete to obtain a methanol solution of 2-methoxyimino-2- [2- (2-methyl phenoxymethyl) phenyl ] acetonitrile; (2) Preparing kresoxim-methyl through pinner reaction, namely cooling a methanol solution of 2-methoxyimino-2- [2- (2-methylphenoxymethyl) phenyl ] acetonitrile to 5-10 ℃, introducing hydrochloric acid gas into a system, controlling a certain temperature range until the reaction is completed after the hydrochloric acid gas is introduced, cooling and suction-filtering after the reaction is completed to obtain a kresoxim-methyl crude product, adding the kresoxim-methyl crude product into aqueous methanol, cooling to 0-20 ℃ after pulping is completed, and suction-filtering to obtain refined kresoxim-methyl; The catalyst in the step (1) is a phase transfer catalyst; The phase transfer catalyst is benzyl triethyl ammonium chloride or tetrabutyl ammonium bromide, and the molar ratio of the catalyst to 2- (2-methyl phenoxymethyl) benzoyl cyanide is 1:0.01.
2. The method for synthesizing kresoxim-methyl according to claim 1, wherein the ratio of 2- (2-methyl phenoxymethyl) benzoyl cyanide to methoxyamine hydrochloride to catalyst to hydrochloric acid gas in the steps (1) and (2) is 1 (1.02-1.1): 0.005-1.05): 1.1 in terms of the molar ratio of pure substances.
3. The method for synthesizing kresoxim-methyl according to claim 2, wherein the ratio of 2- (2-methyl phenoxymethyl) benzoyl cyanide to methoxyamine hydrochloride to hydrochloric acid gas in the steps (1) and (2) is 1:1.05:1.1 based on the molar ratio of pure substances.
4. The method for synthesizing kresoxim-methyl according to claim 1, wherein the phase transfer catalyst is tetrabutylammonium bromide.
5. The method for synthesizing kresoxim-methyl according to claim 1, wherein the water content of the aqueous methanol in the step (2) is 10% -50%.
6. The method for synthesizing kresoxim-methyl according to claim 5, wherein the water content of the aqueous methanol in the step (2) is 20%.

Description

Synthesis method of kresoxim-methyl Technical Field The invention belongs to the technical field of fine chemical industry, relates to a pesticide chemical synthesis technology, and in particular relates to a method for synthesizing kresoxim-methyl. Background The kresoxim-methyl is the earliest discovered methoxy acrylic bactericide, has bactericidal effect, can promote the growth of a plurality of cereal crops, can delay plant senescence and enhance the absorption and utilization of nitrogen and carbon dioxide by plants, and has great application prospect in the market. At present, the main method for preparing kresoxim-methyl is as follows: the synthesis route I is as follows: the method comprises the steps of taking phthalide as a raw material, reacting the phthalide with o-cresol to generate 2- (2-methyl phenoxymethyl) benzoic acid, then chloridizing to obtain acyl chloride, then carrying out cyanidation reaction with sodium cyanide to obtain 2- (2-methyl phenoxymethyl) benzoyl cyanide, adding methanol into the 2- (2-methyl phenoxymethyl) benzoyl cyanide to obtain 2- (2-methyl phenoxymethyl) benzoyl methyl formate, then carrying out oximation reaction with methoxyamino hydrochloride, and carrying out configuration conversion with the hydrochloric acid to obtain kresoxim-methyl. In the preparation method, the total reaction yield is low, the total yield is only 55 percent, the reaction steps and the period are long, and a large amount of hydrochloric acid gas is used in the synthesis method, cannot be recovered after being used and causes great pollution to the environment. The synthesis route II is as follows: the method comprises the steps of preparing acyl chloride by chlorination reaction of o-methylbenzoic acid serving as a raw material through thionyl chloride, then preparing o-methylbenzoyl cyanide by reaction of the acyl chloride and sodium cyanide, then introducing hydrochloric acid gas to obtain o-methylbenzoyl methyl formate, oximating the o-methylbenzoyl methyl formate with methoxylamine hydrochloride, introducing the hydrochloric acid gas to perform configuration transposition to obtain (E) -2-methoxyimino- [ (2-o-methylphenyl) ] methyl acetate, then reacting the (E) -2-methoxyimino- [ (2-o-methylphenyl) ] methyl acetate with bromine, and finally reacting the (E) -2-methoxyimino- [ (2-o-methylphenyl) ] methyl acetate with o-cresol to obtain kresoxim-methyl. The total yield of the process route is only 35%, the cost is high, and a large amount of hydrochloric acid gas is still used. Therefore, the synthesis process with low cost, simple operation, safety, environmental protection and short period is selected to have great economic value. Disclosure of Invention Aiming at the problems, the invention provides a synthetic method of kresoxim-methyl, which has the characteristics of high yield, short reaction period, environmental protection, energy conservation and low cost, and the invention takes 2- (2-methyl phenoxymethyl) benzoyl cyanide and methoxyamine hydrochloride as raw materials, firstly, oximation dehydration is carried out to obtain 2-methoxyimino-2- [2- (2-methyl phenoxymethyl) phenyl ] acetonitrile, and then pinner reaction is carried out to obtain kresoxim-methyl. The specific synthetic route is as follows: The method comprises the following steps: (1) Preparation of 2-methoxyimino-2- [2- (2-methylphenoxymethyl) phenyl ] acetonitrile Adding 2- (2-methyl phenoxymethyl) benzoyl cyanide and methoxyamine hydrochloride into methanol, adding a catalyst, heating to 55-65 ℃, and preserving heat until the 2- (2-methyl phenoxymethyl) benzoyl cyanide remains 0.5% to obtain a methanol solution of 2-methoxyimino-2- [2- (2-methyl phenoxymethyl) phenyl ] acetonitrile; (2) Preparation of kresoxim-methyl by pinner reaction Cooling a methanol solution of 2-methoxyimino-2- [2- (2-methylphenoxymethyl) phenyl ] acetonitrile to 5-10 ℃, introducing hydrochloric acid gas into the system, slowly heating to 15-30 ℃ after the hydrochloric acid gas is introduced, carrying out heat preservation reaction until 10-15% of 2-methoxyimino-2- [2- (2-methylphenoxymethyl) phenyl ] acetonitrile is remained, slowly heating to reflux until 0.5% of 2-methoxyimino-2- [2- (2-methylphenoxymethyl) phenyl ] acetonitrile is remained, carrying out reaction, cooling and suction filtering to obtain a kresoxim-methyl crude product, adding the kresoxim-methyl crude product into aqueous methanol, cooling to 0-20 ℃ after pulping, and suction filtering to obtain the refined kresoxim-methyl. Further, in the steps (1) and (2), the molar ratio of 2- (2-methyl phenoxymethyl) benzoyl cyanide to methoxyamine hydrochloride to catalyst to hydrochloric acid gas is 1 (1.02-1.1): (0.005-1.05): 1.1, and the preferred ratio of 2- (2-methyl phenoxymethyl) benzoyl cyanide to methoxyamine hydrochloride to catalyst to hydrochloric acid gas is 1:1.05:0.01:1.1. Further, the catalyst in the step (1) is at least one of organic base or phase transfer catal