Density functional studies on copper-catalyzed asymmetric cyclopropanation of diazoacetate with alkene

摘要

The chiral bisoxazoline-copper(I)-catalyzed asymmetric cyclopropanation of diazoacetate with alkene was studied by means of the density functional theory (DFT). All the intermediates and the transition states were optimized completely at the B3LYP/6-31G level. As shown, this asymmetric. cyclopropanation is exothermic. The turnover-limiting step for the cyclopropanation is the formation of chiral catalyst-cyclopropyl carboxylate complexes. The dominant products predicted theoretically are (R,R)-cyclopropane, which is in agreement with the experiment. (C) 2004 Elsevier B.V. All rights reserved.