Electrocatalytic intramolecular cross-dehydrogenative coupling for synthesis of fused heterocyclic compounds bearing tetrahydroisoquinoline core

Abstract

An intramolecular cross-dehydrogenative coupling of N-aryl substituted tetrahydroisoquinolines under electrooxidation condition was developed. The addition of TEMPO and BINOL-derived phosphoric acids allowed the reaction to proceed at low electrode potentials and without the need of additional oxidizers and metals. The corresponding fused heterocyclic products were obtained in good to excellent yields under mild conditions. In addition, the catalysis of chiral 3,3-triazolyl BINOL-derived phosphoric acids enabled this coupling reaction in moderate enantioselectivity.