A New Case of Asymmetric Synthesis Using Circularly Polarized Light

Abstract

Abstract Asymmetric photocyclization of N‐methyl N‐aryl enamines by circularly polarized light gives several optically active N‐methyl dihydroindoles. In the synthesis of N‐methyl 2‐phenyl dihydroindole, the optical yield was evaluated to be 0.20%, which is the same order of magnitude as in the asymmetric synthesis of helicenes. The mechanisms of these reactions are discussed.