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 chiral oxazoline 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
摘要 合成了一系列含有半冠醚单元的手性C2对称双(恶唑啉)配体。由铜(I)-三氟甲磺酸盐原位制备的铜配合物和新的手性恶唑啉配体被评估为苯乙烯与重氮乙酸酯对映选择性环丙烷化反应中的手性催化剂。观察到反式和顺式 2-苯基环丙烷羧酸酯的对映选择性分别高达 84% 和 65%。