(Me4N)2[Pt(CO3)2(OH)2]: The Isolated PtIVO6 Carbonato-Complex

The first fully inorganic Pt(IV) carbonato-complex trans-[Pt(CO3)(2)(OH)(2)](2-) with a {PtO6} coordination sphere was isolated as the (Me4N)(2)[Pt(CO3)(2)(OH)(2)] (1) salt. The compound 1 was characterized using single-crystal and powder X-ray diffraction, Raman spectroscopy, infrared spectroscopy (FTIR), electrospray ionization mass spectrometry (ESI-MS), nuclear magnetic resonance spectroscopy (NMR), and thermogravimetric analysis (TG). Density functional theory (DFT) calculations were also performed to analyze the spectral features of the complex. 1 crystallizes in the triclinic system (P-1) with a Z of 1. The trans-[Pt(CO3)(2)(OH)(2)](2-) anion has axial hydroxo ligands and kappa(2)-CO3 ligands, which form an equatorial plane. This anionic complex exhibits notable stability in aqueous solutions, while the axial hydroxo ligand can be readily modified, as exemplified by the acylation of the trans-[Pt(CO3)(2)(OH)(2)](2-) into trans-[Pt(CO3)(2)(OAc)(2)](2-) anion. Furthermore, it has been shown that rigid and glittering platinum coatings can be electrochemically deposited from an aqueous solution of 1 without the addition of surfactants.