Synthesis of cyclometalated (8-methoxynaphthyl)- and [8-(dimethylamino)naphthyl]platinum compounds and their reactivity toward electrophiles. X-ray molecular structures of square-planar (8-methoxynaphthyl)platinum(II) chloride bis(diethyl sulfide) and bis(8-methoxynaphthyl)platinum(II) diethyl sulfide and octahedral fac-bis(8-methoxynaphthyl)methylplatinum(IV) iodide