Enantioselective synthesis of 4,5,6,7-tetrahydroindoles via olefin cross-metathesis/intramolecular Friedel–Crafts alkylation reaction of pyrroles

Abstract

A sequential catalysis involving olefin cross-metathesis/asymmetric intramolecular Friedel–Crafts alkylation of pyrrole derivatives has been developed. A variety of enantioenriched 4,5,6,7-tetrahydroindoles were obtained in good yields and enantioselectivity by combining a Zhan-1B catalyst with a chiral phosphoric acid.