异噁唑草酮中间体合成技术综述

A Summary of the Synthesis of the Intermediate of Isoxaflutole

异噁唑草酮是广泛使用的除草剂,根据硫醚基团氧化的先后顺序,其合成路线可分为前氧化法和后氧化法。两种路线中均涉及到中间体1-环丙基-3-(2-甲磺酰基-4-三氟甲基苯基)丙-1,3-二酮。该1,3-二酮的制备方法主要集中在2-硫甲基-4-三氟甲基苯甲酸或酯与环丙基甲酸酯缩合、2-硫甲基-4-三氟甲基苯乙酮与环丙基甲酸酯缩合、2-硝基-4-三氟甲基苯甲酯或酸与环丙基甲基酮缩合以及β-氨基乙烯基酮水解等。以酮和酯进行缩合反应,反应收率较高,纯度较好,易于工业化生产。

Isoxaflutole is widely used herbicide.According to the order of oxidation of thioether group,the synthetic route of isoxaflutole can be divided into pre-oxidation and post-oxidation.Both routes involve the intermediate 1-cyclopropyl-3-(2-methanesulfonyl-4-trifluoromethylphenyl)propan-1,3-dione.Preparation methods of 1,3-dione can be classif ied as the condensation of 2-thiomethyl-4-trifluoromethyl benzoic acid or ester and cyclopropyl formate,2-thiomethyl-4-trifluoromethyl acetophenone and cyclopropyl formate,2-nitro-4-trifluoromethyl benzyl ester or acid and cyclopropyl methyl ketone,hydrolysis ofβ-amino vinyl ketone,etc.The condensation reaction of ketone and ester has high reaction yield,good purity,suitable for industrial production.