Mo(CO)6- and [Rh(CO)2Cl]2-catalyzed allenic cyclocarbonylation reactions of alkynones: efficient access to bicyclic dienediones.

Allenyl alkynones are efficiently transformed into fused bicyclic dienediones via cyclocarbonylation reaction conditions. Mo(CO)6/DMSO reaction conditions result in the formation of a bicyclo[3.3.0]octenone ring system, and the [Rh(CO)2Cl]2-catalyzed reaction affords bicyclo[4.3.0]nonenone and bicyclo[5.3.0]decenone scaffolds.