Hypervalent Iodine(III)-Mediated Benzannulation of Enamines with Alkynes for the Synthesis of Polysubstituted Naphthalene Derivatives

A series of functionalized 1-amino-2-naphthalenecarboxylic acid derivatives were synthesized from enamines and alkynes via a benzannulation strategy mediated by iodosylbenzene and BF₃·Et₂O. The advantages of this novel benzannulation process include broad substrate scope, good functional group tolerance, and mild reaction conditions without the use of heavy metals.