Cobalt-catalyzed enantioselective reductive addition of ketimine with cyclopropyl chloride to construct chiral amino esters bearing cyclopropyl fragments

Abstract

Chiral amino acid derivatives containing cyclopropyl fragments are high-value drug candidates, but their synthesis is still challenging. We herein report an efficient construction of chiral α-tertiary amino acid derivatives containing cyclopropane fragments, which has been achieved via a cobalt-catalyzed asymmetric reductive addition of α-iminoesters with cyclopropyl chloride. This strategy enables the formation of these valuable motifs with broad functional group tolerance under mild conditions with good yields and excellent enantioselectivities.