A Route to Regioselectively Functionalized Carbazoles, Dibenzofurans, and Dibenzothiophenes through Anionic Cyclization of Benzyne-Tethered Aryllithiums

The treatment of 2-fluorophenyl 2-iodophenylamines, ether, and thioether, easily prepared from commercially available products, with 3.3 equiv of t-BuLi and further reaction with selected electrophiles gives rise to functionalized carbazole, dibenzofuran, and dibenzothiophene derivatives in a direct and regioselective manner. The process involves an anionic cyclization on a benzyne-tethered aryllithium intermediate.