Highly stereoselective cyclopropanation of diazo Weinreb amides catalyzed by chiral Ru(ii)–Amm–Pheox complexes†
Abstract
The first highly stereoselective cyclopropanation of diazo Weinreb amides with olefins was accomplished using chiral Ru(II)–Amm–Pheox complex 7a to give the corresponding chiral cyclopropyl Weinreb amides in high yields (up to 99%) with excellent diastereoselectivities (up to 99 : 1 dr) and enantioselectivities (up to 96% ee).