Achiral Cp*Rh(III)/Chiral Lewis Base Cooperative Catalysis for Enantioselective Cyclization via C–H Activation
Takumaru Kurihara, M. Kojima, Tatsuhiko Yoshino, Shigeki Matsunaga
Abstract
)-H activation with a cooperative catalytic system consisting of a Cp*Rh(III) complex and a chiral Lewis base is described. An α,β-unsaturated acyl ammonium intermediate is generated from a chiral isochalcogenurea catalyst and an acyl fluoride reacts with a metallacycle generated from the Cp*Rh catalyst and a benzylamine derivative. This cooperative catalytic system gives a variety of benzolactams in good yields with excellent enantioselectivities (up to 99:1 er). The results demonstrated that chiral Lewis base catalysis is a powerful tool for controlling the enantioselectivity of transition metal-catalyzed C-H functionalizations.
Topics & Concepts
ChemistryEnantioselective synthesisCatalysisLewis acids and basesBenzylamineChiral Lewis acidMedicinal chemistryOrganic chemistryStereochemistryCombinatorial chemistryCatalytic C–H Functionalization MethodsCyclopropane Reaction MechanismsSynthesis and Catalytic Reactions