Synthesis of Dihalonaphthalenes via Silver-Catalyzed Halogenation and Electrophilic Cyclization of Terminal Alkynols.

Herein, we report a silver-catalyzed halogenation and electrophilic cyclization reaction based on the trifunctionalization of terminal alkynols with NBS or iodine monochloride in a step-efficient synthetic way to produce homo/heterodihalogenated naphthalene derivatives bearing two different halogen atoms in moderate to good yields. This methodology readily accommodates various functional groups, including electron-withdrawing nitro, cyano, acid-sensitive dioxazolyl, and alkoxy groups.