Synthesis process of 2-amino-5-chloro-3-methylbenzoic acid intermediate 2-(hydroxyimino)-N-(2-methylphenyl)acetamide

The invention discloses a novel process for synthesizing a 2-amino-5-chloro-3-methylbenzoic acid intermediate, namely 2-(hydroxyimino)-N-(2-methylphenyl)acetamide. According to the process, o-aminotoluene is used as a main starting raw material, and synthesis of 2-(hydroxyimino)-N-(2-methylphenyl)acetamide is realized through two steps including amino acetylation and oximation. Compared with the prior art, the process of the invention has the advantages that product yield reaches 97% or above, the generation of waste salt sodium chloride and sodium sulfate is reduced by three times or above, intermediate raw materials are low in price, process is simple, cost is reduced, and environmental and economic benefits are improved. 本发明公开了一种K胺中间体2-(羟基亚氨基)-N-(2-甲基苯基)乙酰胺合成新工艺。该工艺以邻氨基甲苯为主要起始原料，通过氨基乙酰化和肟化两步，实现2-(羟基亚氨基)-N-(2-甲基苯基)乙酰胺的合成。与现有工艺相比产品收率达到97％以上同时减少3倍以上废盐氯化钠和硫酸钠的产生，且中间原料价格低，工艺简单，成本下降，实现环境与经济效益双方面提高。