Enantioselective Catalytic Ring Expansion of Methylenecyclopropane Carboxamides Promoted by a Chiral Magnesium Lewis Acid
作者:Catherine Taillier、Mark Lautens
DOI:10.1021/ol0628614
日期:2007.2.1
A catalytic enantioselective ring expansion of monoactivated methylenecyclopropanes (MCP) in the presence of N-tosyl aldimines was developed using a chiral bis(oxazoline) ligand-MgI2 complex. After evaluation of ligands and optimization of the reaction conditions, the reaction has been applied to a variety of aromatic and heteroaromatic aldimines providing the corresponding trans-C2,C3-disubstituted
使用手性双(恶唑啉)配体-MgI2配合物,开发了在N-甲苯磺酰基醛亚胺存在下单活化亚甲基环丙烷(MCP)的催化对映选择性环扩展。在评估了配体并优化了反应条件后,该反应已应用于多种芳族和杂芳族亚胺,可提供相应的反式C2,C3-二取代亚甲基吡咯烷类化合物,收率通常较高(大于52%),最高可达86% ee。[反应:请参见文字]。