A facile three-component [3+2]-cycloaddition/annulation domino protocol for the regio- and diastereoselective synthesis of novel penta- and hexacyclic cage systems, involving the generation of two heterocyclic rings and five contiguous stereocenters

An expedient, three-component, [3+2]-cycloaddition/annulation domino protocol for the synthesis of a series of cage penta- and hexacyclic compounds in good to excellent yields is described. The ring systems thus generated contain as structural elements bridged, fused and spiro rings and were obtained with complete selectivity through the creation of two C–C and two C–N bonds, which led to the generation of two azaheterocyclic rings, four carbon and one nitrogen adjacent stereocentres, three of which are quaternary.