Rhodium(III)/Chiral Carboxylic Acid Catalyzed Enantioselective C(sp3)-H Alkylation of 8-Ethylquinolines with α,β-Unsaturated Carbonyl Compounds.

The enantioselective C-H alkylation of 8-ethylquinolines with enones or acrolein using a RhIII catalyst and a chiral carboxylic acid is described. Under mild reaction conditions, a binaphthyl-based chiral carboxylic acid enables the enantioselective cleavage of the 8-ethylquinoline C(sp3)-H bond. The obtained results demonstrate the utility of the combination of a high-valent group 9 metal catalyst and a chiral carboxylic acid for the enantioselective C(sp3)-H activation and the subsequent C-C bond formation.