possible to trap some of the initially formed carbonyl ylide dipoles with a reactive dipolarophile such as DMAD. In other cases, cyclization of the dipole to the epoxide is much faster than bimolecular trapping. A related cyclization/rearrangement sequence occurred when diazo ketoamides derived from the cyclic pyrrolidone and piperidone ring systems were subjected to catalytic quantities of Rh(II) acetate