Pd(II)-catalyzed double C–H activation of 1-aryl-7-azaindoles for the rollover annulation of γ-hydroxy-α,β-acetylenic esters

Abstract

A diverse range of polycyclic azaindole frameworks has been synthesized from 1-aryl-7-azaindoles and γ-hydroxy-α,β-acetylenic esters using a catalytic amount of Pd(OAc)₂and 2 equiv Cu(OAc)₂. This is the first report on the rollover C–H annulation of 1-aryl-7-azaindoles with γ-hydroxy-α,β-acetylenic esters. This method provides a direct access to angularly fused azaindoles that are closely resemble to biologically active structural scaffolds.