Regioselective synthesis of vinyl halides, vinyl sulfones, and alkynes: a tandem intermolecular nucleophilic and electrophilic vinylation of tosylhydrazones.

A diazo species is trapped in an intermolecular fashion by two independent ion species in tandem at the carbene center to install an electrophile and a nucleophile on the same carbon. This metal-free concept, which is unprecedented, has been illustrated by regioselective synthesis of a variety of vinyl halides, vinyl sulfones, and alkyne derivatives.