Inter- and Intramolecular Cyclopropanations of Diazo Weinreb Amides Catalyzed by Ruthenium(II)-Amm-Pheox

Inter- and intramolecular cyclopropanations of a series of diazo Weinreb amides and trans-allylic diazo Weinreb amide derivatives have been achieved using chiral ruthenium(II)-Amm-Pheox catalyst to give the corresponding chiral cyclopropyl Weinreb amides in excellent yield (up to 99%) with excellent enantioselectivity (up to 99% ee). The chiral products could easily undergo useful synthetic transformations to give the corresponding aldehydes, alcohols and ketones in high yields and enantioselectivities.