液相氧化法制备维生素K中间体β-甲基萘醌的研究

Study on preparation of vitamin K intermediates β-methy-1,4-naphthoquinone with liquid phase oxidation

用溴酸钾氧化β-甲基萘制备β-甲基萘醌。考察了相转移催化剂种类、反应温度、反应时间、氧化剂与原料的配比等因素对目标产物收率的影响,从而获得了最佳反应条件:相转移催化剂为四丁基溴化铵,反应温度80℃,反应时间5 h,氧化剂与原料的配比2.5∶1。在以上较优条件下,得到目标产物β-甲基萘醌的收率为48.12%。比传统的工业生产大约高出10个百分点。

β-Methy-1,4-naphthoquinone was prepared by oxidating β-methylnaphthalene with KBrO3 in this paper first. The effects of phase transfer catalysts, temperature, time and mole ratio of oxidant to raw material on the yield have been investigated. The optimal conditions were determined as follows： phase transfer catalyst NH4BrE[C4H9]4, reaction temperature 80℃ , reaction time 5 h and mole ratio of oxidant to raw material 2.5： 1. The yield of menadione was 48.12% under above conditions,which was higher 10% than the traditional method.