Palladium-catalyzed cascade cyclization/intramolecular redox-relay Heck arylation of alkenols: access to tetrahydro-β-carbolines from 2-(hydroxyalkenynyl)sulfonanilides†

Abstract

A palladium-catalyzed cascade reaction for the synthesis of tetrahydro-β-carbolines and other polycyclic indoles from 2-(hydroxyenyl)sulfonanilides by combining the Pd(ii)-catalyzed cyclization of alkynes and intramolecular redox-relay Heck arylation of alkenols is presented. This method enables the construction of two rings and installs a remote carbonyl group in a single operation, offering broad synthetic utility for further elaborations.