Synthesis of Novel Chiral Semicrown Ether‐Like Bis(oxazoline) Ligands and Application in Enantioselective Cyclopropanation of Styrene
作者:Zhan‐Yue Wang、Da‐Ming Du、Jia‐Xi Xu
DOI:10.1081/scc-200048469
日期:2005.1
Abstract A series of chiral C2‐symmetric bis(oxazoline) ligands containing semicrown ether unit were synthesized. The copper complexes prepared in situ from copper(I)‐triflate, and the new chiraloxazoline ligands were assessed as chiral catalysts in the enantioselective cyclopropanation of styrene with diazoacetates. Enantioselectivities up to 84% and up to 65%, respectively, for trans‐ and cis‐2