Reaction of Diaryl-1,2-diones with Triphenylphosphine and Diethyl Azodicarboxylate Leading to N,N-Dicarboethoxy Monohydrazones via a Novel Rearrangement

A mechanistically novel reaction of diaryl-1,2-diones with diethyl azodicarboxylate and triphenylphosphine to afford N,N-dicarboethoxy monohydrazones is described. The reaction proceeds via a nitrogen to nitrogen migration of a carboethoxy group.