Synthesis of imine–amine type of chiral ligands and their application in the asymmetric cyclopropanation of olefins with diazoacetates
作者:Jun-An Ma、Li-Xin Wang、Wei Zhang、Qi-Lin Zhou
DOI:10.1016/s0957-4166(01)00513-4
日期:2001.11
Novel chiral ligands 1, which possess both imine and amine moieties, were prepared from readily available homochiral materials. Copper complexes of 1 were prepared in situ and used in the asymmetriccyclopropanation of olefins with alkyl diazoacetates to give cyclopropanecarboxylates, inducing e.e. values of up to 87%. The size of the chelate ring in the copper complexes influenced the enantioselectivity