三苯甲基取代烯烃的环氧化研究

Study on the Epoxidation of Triphenylmethyl Substituted Olefins

合成了6种三苯甲基取代烯烃.以二甲基二氧杂环丙烷作为主要氧化剂,在催化剂(R,R)-salen Mn(III)的催化下,进行不对称环氧化,其不对称环氧化产物ee值较高(81%).初步研究表明,二甲基二氧杂环丙烷(DMD)和(R,R)-salen Mn(III)的环氧化体系对于含亚甲基的三苯甲基取代的烯烃的氧化产率高但对映选择性差,对于不含亚甲基的三苯甲基取代的烯烃的氧化产率低但对映选择性好.

Six olefins bearing triphenylmethyl group were synthesized. High enantioselectivities （81%） have been obtained for asymmetric epoxidation of the olefins using the （R,R）-salen Mn（Ⅲ） complex as catalyst and dimethyldioxirane （DMD） as primary oxidant. The epoxides were obtained in good yields and low enantioselectivities by the oxidation of olefins having methylene using the （R,R）-salen Mn（Ⅲ） complex as catalyst and dimethyldioxirane （DMD） as oxygen donor, the opposite results were obtained by the oxidation of olefins no having methylene by the same way.