Functionalization of Diazo Groups by the Nucleophilic Addition of Two Molecules of a Dimethylsulfonium Ylide to α-Diazo-ß-ketoesters/ketones: Synthesis of Highly Functionalized Hydrazones.

The intrinsic electrophilic feature for the terminal nitrogen of α-diazo-ß-ketoesters/ketones has been elucidated by the intermolecular nucleophilic addition of two molecules of a dimethylsulfonium ylide. This methodology allows for access to highly functionalized hydrazones with a broad scope and good functional group tolerance. The reaction operates under simple and mild conditions without using a catalyst.