Efficient Synthesis of Maleimides and Carbazoles via Zn(OTf)₂-Catalyzed Tandem Annulations of Isonitriles and Allenic Esters

Abstract

Lewis acid Zn(OTf)(2)-catalyzed tandem annulations of isonitriles and allenic esters which lead to efficient and flexible syntheses of a range of biologically significant maleimides and carbazoles and related compounds are reported. A mechanistic rationale is proposed to account for the observed reactivity.