Asymmetric ?-Chlorination of ?-Keto Esters Using Hypervalent Iodine-Based Cl-Transfer Reagents in Combination with Cinchona Alkaloid Catalysts

ABSTRACT: We herein report an unprecedented strategy for the asymmetric ?-chlorination of ?-keto esters with hypervalent iodine-based Cl-transfer reagents using simple Cinchona alkaloid catalysts. Our investigations support an ?-chlorination mechanism where the Cinchona species serves as a nucleophilic catalyst by reacting with the chlorinating agent to generate a chiral electrophilic Cl-transfer reagent in situ. Using at least 20 mol-% of the alkaloid catalyst allows for good yields and enantioselectivities for a variety of different ?-keto esters-under operationally simple conditions.

SUBMITTER: Stockhammer L 

PROVIDER: S-EPMC7116688 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature