新型除草剂唑啉草酯的合成工艺

Synthetic Process of Novel Herbicides Pinoxaden

[目的]旨在探索一条适合工业化生产唑啉草酯的工艺路线。[方法]一缩二乙二醇与甲烷磺酰氯反应,生成甘二醇二甲烷磺酸酯,再与叠氮二羧酸二叔丁酯环化得到4,5-双-叔丁氧基羰基-[1,4,5]氧杂二氮杂草,然后在乙酸溴化氢溶液中脱羧得到中间体[1,4,5]-氧杂二氮杂草二氢溴酸盐;2,6-二乙基-4-甲基苯胺经过Sandmeyer反应,得到2,6-二乙基-4-甲基溴苯,与丙二腈在碘化亚铜催化下偶合,得到2,6-二-乙基-4-甲基苯基丙二腈,最后在过氧化氢溶液中水解得到2,6-二乙基-4-甲基苯基丙二酰胺;在三乙胺的作用下,2,6-二-乙基-4-甲基苯基丙二腈与[1,4,5]-氧杂二氮杂草二氢溴酸盐反应得到8-(2,6-二乙基-4-甲基苯)四氢吡唑[1,2d][1,4,5]-氧杂二氮杂草-7,9-二酮,在4-二甲氨基吡啶的催化下,与新戊酰氯反应,得到目的产物唑啉草酯。[结果]经1H NMR光谱鉴定,产品结构与唑啉草酯结构一致。[结论]该工艺简单经济、条件温和、适合工业化生产。

[Aims] This article aims to explore and optimize a reasonable route of pinoxaden on industrial scale. [Methods] Diethylene glycol dimcthanesulfonate was prepared by the reaction of diethylene glcycol with methanesulfonyl chloride, then reacted with ditert-butyl hydrazine-l,2-dicarboxylate to give the 4,5-bis-tert- butyloxycarbonyl- [ 1,4,5]oxadiazcpan, which was decarboxylated in the solution of hydrogen bromide in glacial acetic acid to get [1,4,5] oxadiazcpane dihydrobromide; 2,6-diethyl-4-mcthyl-bromobenzene was prepared from 2,6-diethyl- 4-methyl-aniline by the Sandmeyer reaction, coupled with malononitrile under CuI catalysis to give the 2,6-diethyl- 4-mcthyl-phenyl-malononitrile, which was hydrolyzed in H202 to get the product of 2,6-diethyl-4-methylphcnylmalonic acid diamide; in the present of triethylamine, the 8-（2,6-diethyl-4-methylphenyl）tetrahydropyrazolo [1,2-d] [1,4,5] oxadiazepine-7,9-dione was prepared by the reaction of 2,6-diethyl-4-methylphenylmalonic acid diamide with [1,4,5] oxadiazepane dihydrobromide, then reacted with pivaloy chloride to give the target product ofpinoxaden; [Results] The product thus obtained is identified with tH NMR. [Gonelusions] This process is simple, warm and economical, which is suitable for industrial scale manufacture.