离子液体中氧化锰八面体分子筛催化醇的氧化

按文献方法制备了3种八面体MnO6分子筛催化剂K-OMS-2、H-K-OMS-2和Cu-OMS-2,用SEM和XRD测试技术表征了它们的结构和组成。考察了这3种催化剂对用氧气选择性氧化醇为相应的醛或酮的催化作用,研究了采用不同OMS-2在离子液体bmim]PF6中反应时间和反应温度对催化反应的影响。其中H-K-OMS-2对苄醇和烯丙醇氧化的转化率和选择性均超过90%。催化剂和离子液体可分别用萃取法和减压蒸馏法从反应体系中回收,其中减压蒸馏法回收循环使用效果较好。

Selective Aerobic Oxidation of Alcohols Catalyzed by Octahedral Molecular Sieves in Ionic Liquids

Three manganese oxide octahedral molecular sieves(OMS2), K-OMS2, H-K-OMS-2 and Cu-OMS-2, were synthesized according to the literature. The structure and composition of the obtained materials were characterized by SEM and XRD. OMS-2 was applied to the selective oxidation of alcohols to generate corresponding aldehydes or ketones. The effects of reaction time and temperature on the catalytic reactions were investigated in ionic liquid bmim]PF6 when different OMS-2 materials were used as catalysts. The conversion and selectivity of benzylic or allylic alcohols catalyzed by H-K-OMS-2 both reached over 90%. The solvent and catalyst could be recovered from the reaction system by extraction method and vacuum distillation method respectively. The catalytic system recovered by vacuum distillation method showed better recycling performance.