The single crystal X-ray structure of the supramolecular complex formed between diphenyl-λ³-iodane (Ph₂IBF₄) or 1-alkynyl(phenyl)-λ³-iodane [Bu^tCCI(Ph)BF₄] and 1,10-phenanthroline indicates a hitherto unknown distorted trigonal bipyramidal geometry around iodine(III), in which 1,10-phenanthroline acts as a bidentate ligand and occupies equatorial sites.