Intra- and intermolecular reactions of nucleophilic carbenes

General properties of nucleophilic carbenes are addressed briefly. The preparation of oxadiazoline precursors of such carbenes, and some of their chemical reactions, are presented. Intramolecular reactions include rearrangement and attack by the carbene center on a tethered functional group. Intermolecular reactions include nucleophilic attack at the carbonyl carbon of isocyanates and at the triple bond of dimethyl acetylenedicarboxylate.