阅读说明：本技术 一种草铵膦中间体的合成方法 (Synthesis method of glufosinate-ammonium intermediate ) 是由 姜宇华 陈佳 陶亚春 栾小兵 纪雷 于 2019-09-30 设计创作，主要内容包括：本发明涉及一种草铵膦中间体的合成方法,使甲基丙醛基磷酸乙酯和NH<Sub>4</Sub>CN在氯化铵和氨水的存在下反应制得草铵膦中间体草铵膦氨基腈。本发明的方法能够有效避免传统工艺中生成氯化铵和氯化钠的混盐,从源头上解决了处理混盐的难题,也能够避免使用价格昂贵的三甲基硅氰作为氰化试剂,并且,本发明的方法具有反应条件温和、收率高的特点,从而降低了生产成本,工业化前景好。(The invention relates to a synthesis method of glufosinate-ammonium intermediate, which is used for synthesizing methyl propionaldehyde ethyl phosphate and NH 4 CN reacts in the presence of ammonium chloride and ammonia water to prepare glufosinate-ammonium aminonitrile as a glufosinate-ammonium intermediate. The method can effectively avoid the generation of mixed salt of ammonium chloride and sodium chloride in the traditional process, solves the problem of treating the mixed salt from the source, and can also avoid the use of expensive trimethylsilylcyanide as a cyaniding reagent.)

1. A synthetic method of a glufosinate-ammonium intermediate is characterized by comprising the following steps: reacting methylpropionaldehyde ethyl phosphate and NH₄CN reacts in the presence of ammonium chloride and ammonia water to prepare glufosinate-ammonium aminonitrile as a glufosinate-ammonium intermediate.

2. A synthesis method of a glufosinate intermediate according to claim 1, characterized in that: the methyl propyl aldehyde ethyl phosphate and the NH₄The feeding molar ratio of CN is 1: 1-6.

3. A synthesis method of a glufosinate intermediate according to claim 1, characterized in that: the reaction temperature is 15-30 ℃.

4. A synthesis method of a glufosinate intermediate according to claim 1, characterized in that: the feeding molar ratio of the methyl propyl aldehyde ethyl phosphate to the ammonium chloride is 1: 1-6.

5. The method of synthesizing a glufosinate intermediate according to claim 4, characterized in that: the feeding molar ratio of the methyl propyl aldehyde ethyl phosphate to the ammonium chloride is 1: 1.5-3.

6. A synthesis method of a glufosinate intermediate according to claim 1, characterized in that: the feeding molar ratio of the methyl propyl aldehyde ethyl phosphate to the ammonia in the ammonia water is 1: 1-6.

7. A synthesis method of a glufosinate intermediate according to claim 1, characterized in that: after the reaction is finished, adding hydrochloric acid into the reaction solution, heating up and refluxing, then cooling down, introducing ammonia gas, filtering out ammonium chloride, adding methanol and recrystallizing to obtain the glufosinate-ammonium aminonitrile.

8. A synthesis method of a glufosinate intermediate according to claim 1, characterized in that: the NH₄CN is fed in the form of an ammonium cyanide aqueous solution, wherein the mass content of the ammonium cyanide in the ammonium cyanide aqueous solution is 20-35%.

9. A synthesis method of a glufosinate intermediate according to claim 1 or 8, characterized in that: the NH₄The preparation method of CN comprises the following steps: mixing NaCN and ammonium bicarbonate in water, stirring and reacting at 10-20 ℃ to form sodium bicarbonate precipitate, and filtering to obtain NH₄And (3) CN aqueous solution.

10. A synthesis method of a glufosinate intermediate according to claim 1, characterized in that: the preparation method of the methyl propionaldehyde ethyl phosphate comprises the following steps: the methyl diethyl phosphite and acrolein are subjected to Michael reaction in the presence of ethanol, and then are hydrolyzed under acidic conditions to generate the methyl propionaldehyde ethyl phosphate.

11. A synthesis method of a glufosinate intermediate according to claim 10, characterized in that: the feeding molar ratio of the diethyl methylphosphite to the acrolein is 1: 1-1.2.

12. A synthesis method of a glufosinate intermediate according to claim 10, characterized in that: the feeding temperature of the reaction is controlled to be 10-20 ℃, and the reaction temperature is controlled to be 20-50 ℃.

Technical Field

The invention particularly relates to a synthesis method of a glufosinate-ammonium intermediate.

Background

The glufosinate ammonium salt is developed and produced by German Hurst company in the last 80 century, and has the characteristics of high efficiency, low toxicity, easy degradation and the like besides the herbicidal activity.

Glufosinate-ammonium cyanamide is an important intermediate in the glufosinate-ammonium synthesis process, methyl phosphite and acrolein are subjected to addition reaction and then subjected to acidolysis, and then react with cyanide and ammonia/ammonium chloride to obtain intermediate glufosinate-ammonium cyanamide, the traditional cyanides are sodium cyanide and potassium cyanide, so that the problem of separation of ammonium chloride and sodium chloride or potassium chloride is faced, and CN109879910A discloses that trimethylsilyl cyanide is used as a cyaniding reagent, but the price is high, the atom economy is poor, and the industrial production is not suitable.

At present, ammonium cyanide is not reported to be used for synthesizing cyanamide as an intermediate of glufosinate-ammonium.

Disclosure of Invention

The invention aims to provide a method for synthesizing a glufosinate-ammonium intermediate with a cyanide reagent, which is cheap.

In order to solve the technical problems, the invention adopts the following technical scheme:

a synthetic method of glufosinate-ammonium intermediate, which is to make methyl propionaldehyde ethyl phosphate and NH₄CN reacts in the presence of ammonium chloride and ammonia water to prepare glufosinate-ammonium aminonitrile as a glufosinate-ammonium intermediate.

The reaction equation of this step is:

preferably, said methylpropionaldehyde ethyl phosphate and said NH₄The feeding molar ratio of CN is 1: 1-6, and the preferable ratio is 1: 1.5-3; more preferably 1: 1.5-2.5.

Preferably, the reaction temperature is 15-30 ℃.

Preferably, the feeding molar ratio of the methylpropionaldehyde ethyl phosphate to the ammonium chloride is 1: 1-6, further preferably 1: 1.5-3, and more preferably 1: 1.5-2.5.

Preferably, the feeding molar ratio of the methylpropionaldehyde ethyl phosphate to ammonia in the ammonia water is 1: 1-6, further preferably 1: 1.5-5.5, and more preferably 1: 1.5-4.5.

Preferably, after the reaction is finished, adding hydrochloric acid into the reaction solution, heating and refluxing, then cooling, introducing ammonia gas, filtering out ammonium chloride, adding methanol, and recrystallizing to obtain the glufosinate-ammonium aminonitrile.

Preferably, said NH₄CN is fed in the form of an ammonium cyanide aqueous solution, wherein the mass content of the ammonium cyanide in the ammonium cyanide aqueous solution is 20-35%.

Preferably, said NH₄The preparation method of CN comprises the following steps: mixing NaCN and ammonium bicarbonate in water, stirring and reacting at 10-20 ℃ to form sodium bicarbonate precipitate, and filtering to obtain NH₄And (3) CN aqueous solution.

Preferably, the preparation method of the methyl propionaldehyde ethyl phosphate comprises the following steps: the methyl diethyl phosphite and acrolein are subjected to Michael reaction in the presence of ethanol, and then are hydrolyzed under acidic conditions to generate the methyl propionaldehyde ethyl phosphate.

The reaction equation of this step is:

further preferably, the feeding molar ratio of the diethyl methylphosphite to the acrolein is 1: 1-1.2.

Further preferably, the feeding temperature of the reaction is controlled to be 10-20 ℃, and the reaction temperature is controlled to be 20-50 ℃.

The invention takes methyl diethyl phosphite as a raw material to perform Michael reaction with acrolein to obtain intermediate acetal, the acetal is hydrolyzed under acidic condition to produce phosphor-aldehyde, and the phosphor-aldehyde is reacted in NH₄And performing Strecker reaction in ammonia water solution of CN and ammonium chloride to obtain the key intermediate of glufosinate-ammonium aminonitrile. The synthetic route has the advantages of few steps, short reaction period, simple and convenient operation, cheap raw materials, reaction cost reduction, avoidance of mixed salt generation of ammonium chloride and sodium chloride, suitability for large-scale industrial production and capability of solving the problem that waste salt cannot be treated from the source.

Due to the implementation of the technical scheme, compared with the prior art, the invention has the following advantages:

the method can effectively avoid the generation of mixed salt of ammonium chloride and sodium chloride in the traditional process, solves the problem of treating the mixed salt from the source, and can also avoid the use of expensive trimethylsilylcyanide as a cyaniding reagent.

Detailed Description

The present invention will be described in further detail with reference to specific examples. It is to be understood that these embodiments are provided to illustrate the basic principles, essential features and advantages of the present invention, and the present invention is not limited by the following embodiments. The implementation conditions used in the examples can be further adjusted according to specific requirements, and the implementation conditions not indicated are generally the conditions in routine experiments. The contents are all mass contents.