Benziodoxole Triflate as a Versatile Reagent for Iodo(III)cyclization of Alkynes.

The utility of benziodoxole triflate, derived from α,α-bis(trifluoromethyl)-2-iodobenzyl alcohol, as a versatile reagent for iodo(III)cyclization via electrophilic activation of alkyne, is reported herein. The reagent promotes cyclization of alkynes tethered to a variety of nucleophilic moieties, affording benziodoxole-appended (hetero)arenes such as benzofurans, benzothiophenes, isocoumarins, indoles, and polyaromatics under mild conditions. This unprecedented class of (hetero)aryl-IIII compounds proved easy to purify, stable, and amenable to various synthetic transformations.