Axial ligand effect on the reaction mechanism of head-to-head pivalamidato-bridged Pt(III) binuclear complex containing an equatorial bromide ligand with acetone

The axial ligand substitution reactions of head-to-head (HH) pivalamidato-bridged platinum(III) binuclear complexes containing equatorial Br− ligands, ([(H2O)(NH3)2Pt(μ-pivalamidato)2Pt(Br)2(OH2)]2+ (complex 1) and [(Br)(NH3)2Pt(μ-pivalamidato)2Pt(Br)2(Br)] (complex 2)) with acetone were kinetically investigated in acidic aqueous solutions. A reaction mechanism involving an intermediate with one π-coordinated acetone molecule was proposed for complex 1, in contrast, a reaction mechanism involving an intermediate with two π-coordinated acetone molecules on the axial sites was proposed for complex 2.