Rh(III)-Catalyzed [4 + 2] Annulation of Indoles with Diazo Compounds: Access to Pyrimido[1,6-<i>a</i>]indole-1(2<i>H</i>)-ones

Abstract

The Rh(III)-catalyzed regioselective C2-H bond carbenoid insertion/cyclization of N-amidoindoles with α-acyl diazo compounds has been developed. This method provides a novel approach to 2H-pyrimido[1,6-a]indol-1-ones with a broad range of functional group tolerance. The synthetic utilities of the approach are demonstrated by versatile chemical transformations.