The photohydrochlorination of platinum(IV) chloride in chloroform

Abstract

When irradiated at 240 nm, PtCl 4 in CHCl 3 is converted to H 2PtCl 6. When irradiated at wavelengths longer than 265 nm, PtCl 4 is converted to H 2PtCl 4 and H 2PtCl 6 in equal amounts. The latter reaction is suggested to proceed by dissociation of chlorine from a ligand to metal charge transfer excited state of Pt(IV) through a Pt(III) intermediate that disproportionates. The 240 nm photoreaction includes a second, solvent-initiated pathway, suggested to involve CCl 3 radicals from the photolysis of chloroform, which attack the PtCl 4 oligomer to create a Pt(V) intermediate.