Asymmetric Catalysis of Intramolecular Cyclopropanation of 5-Aryl-1-diazo-1-mesitylsulfonyl-5-hexen-2-ones
作者:Takashi Sawada、Masahisa Nakada
DOI:10.1002/adsc.200505173
日期:2005.10
We have examined the catalytic asymmetric intramolecular cyclopropanation (IMCP) reactions of 5-aryl-1-diazo-1-mesitylsulfonyl-5-hexen-2-ones, and found that the substituent of the 5-aryl group dramatically changes the enantioselectivity. That is, no enantioselectivity was observed when the substituent was a methoxy group; however, enantioselectivity was moderate when the substituent was a methylenedioxy
我们检查了5-芳基-1-重氮-1-间苯磺酰基磺酰基-5-己烯-2-酮的催化不对称分子内环丙烷化(IMCP)反应,发现5-芳基的取代基极大地改变了对映选择性。即,当取代基为甲氧基时,没有观察到对映选择性。然而,当取代基为亚甲基二氧基或叔丁基二甲基甲硅烷氧基时,对映选择性适中,而当缺少(96%ee)或苯甲酰氧基(93%ee)时,对映选择性显着增加。