A Late-Transition Metal Oxo Complex: K 7 Na 9 [O=Pt IV (H 2 O)L 2 ], L = [PW 9 O 34 ] 9-

Abstract

Terminal mono-oxo complexes of the late transition metal elements have long been considered too unstable to synthesize because of repulsion between the oxygen electrons and the mostly filled metal d orbitals. A platinum(IV)-oxo compound flanked by two polytungstate ligands, K ₇ Na ₉ [O=Pt(H ₂ O)L ₂ ], L = [PW ₉ O ₃₄ ^9– ], has now been prepared and isolated at room temperature as air-stable brown crystals. X-ray and neutron diffraction at 30 kelvin revealed a very short [1.720(18) angstrom] Pt–O bond and no evidence of a hydrogen atom at the terminal oxygen, ruling out a better precedented Pt–OH complex. Density functional theory and spectroscopic data account for the stability of the Pt(IV)-oxo unit by electron withdrawal into delocalized orbitals of the polytungstates.