申请人:Zhang X. Peter
公开号:US20120077959A1
公开(公告)日:2012-03-29
Cobalt(II) complexes of the D
2
-symmetric chiral porphyrins are effective catalysts for asymmetric cyclopropanation reactions with succinimidyl diazoacetate. The Co-catalyzed reaction is suitable for various olefins, providing the corresponding cyclopropane succinimidyl esters in high yields and excellent diastereo- and enantio-selectivity. The resulting enantioenriched cyclopropane succinimidyl esters can serve as convenient synthons for the general synthesis of optically active cyclopropyl carboxamides through mild reactions with a wide range of amine derivatives, including unprotected peptides and amino sugars