The heterocyclic aryne precursors, (phenyl)[1-phenyl-6-(trimethylsilyl)benzotriazol-5-yl] iodonium triflate and [3-ethoxycarbonyl-6-(trimethylsilyl)indazol-5-yl](phenyl)iodonium triflate, were prepared from the cycloadducts of 4,5-bis(trimethylsilyl)benzyne generated from (phenyl)[2,4,5-tris(trimethylsilyl)phenyl]iodonium triflate. These precursors provide the corresponding arynes, 1-phenyl-5,6-didehydrobenzotriazole and 3-ethoxycarbony1-5,6-didehydroindazole, to give the corresponding polycyclic heteroaromatic compounds in good to high yields.