Efficient synthesis of maleimides and carbazoles via Zn(OTf) 2-catalyzed tandem annulations of Lsonitriles and allenic esters
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.