Synthesis of 2,4-diiodoquinolines via the photochemical cyclization of o-alkynylaryl isocyanides with iodine.

Upon photoirradiation of o-alkynylaryl isocyanides in the presence of iodine, the intramolecular cyclization of o-alkynylaryl isocyanides proceeds to afford the corresponding 2,4-diiodoquinolines in good yields. 2,4-Diiodoquinolines can be employed in transition metal-catalyzed cross-coupling reactions.