The first direct synthesis of an alkynyl(phenyl)iodonium salt from iodobenzene and an unprotected alkyne is described. The synthesis of the corresponding alkenyl(phenyl)iodonium salt is achieved from the TMS-alkyne, simply by means of changing the solvent. The one-pot synthesis of 1-arylbenziodoxolones and other iodine(III) compounds from iodine(I) precursors is also presented.