Asymmetric epoxidation of styrene in chiral microreactor of cyclodextrin

作者：Xiao Zisheng^*; Lan Zhili; Yin Dulin; Liu Fang; Li Chuanhua

来源：Chinese Journal of Catalysis, 2007, 28(5): 469-473.

• styrene
• cyclodextrin
• inclusion complex
• dioxirane
• epoxidation
• synergistic catalysis
• epoxyethylbenzene

The asymmetric epoxidation of styrene included by cyclodextrins with dioxirane produced in situ from ketones and potassium peroxymonosulfate (Oxone((R))) was achieved. The effects of different cyclodextrins and ketones on the epoxidation of styrene were investigated, and the possible mechanism for the synergistic catalysis of cyclodextrins and ketones was suggested. The results indicated that beta-cyclodextrin had good ability of chiral recognition to dioxirane that was generated in situ from methyl isobutyl ketone (MIBK) and Oxone((R)). Various factors, such as molar ratio of MIBK to cyclodextrin inclusion complex, NaHCO3 amount, reaction time, and reaction temperature, that affected the enantiometric excess of the reaction products were examined, and the maximum enantiometric excess of 1,2-epoxyethylbenzene was up to 46 % under the optimal reaction conditions.

• 出版日期2007-5
• 单位湖南师范大学