Direct Assembly of Polysubstituted Naphthalenes via a Tandem Reaction of Benzynes and α-Cyano-β-methylenones.

A mild and transition-metal-free benzannulation reaction for the construction of the naphthalene skeleton has been described. Benzynes react with α-cyano-β-alkylenones through a tandem nucleophilic addition/cyclization/aromatization process to afford polysubstituted naphthalenes in 50-94% yields.