Sythesis, characterization and reactivity of platinum (II) peroxo, alkoxide and triflate compunds

Abstract

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] The chemistry of a collection of platinum(II) compounds, including peroxo, alkoxide and triflate compounds, were synthesized and studied. This involved a rather wide range of platinum chemistry, but the overall mindset was always directed toward functionalization of small molecules, particularly alkenes. The synthesis of the first bidentate phosphine platinum(II) peroxo compounds were achieved from the metathesis of bidentate phosphine platinum dichloride with potassium superoxide in DMF. A high quality crystal structure of the dpppPtO2 derivative was solved. The O-O bond length, 1.523 Å, supported the assignment of the peroxo ligand. Furthermore, the reactivity of these compounds with CO, CO2, SO2, PPh3 and alkenes was studied. All derivatives oxidized triphenylphosphine to triphenylphosphine oxide. None of the derivatives were successful in oxidizing an alkene. Addition of CO resulted in the formation of a carbonato compound for all 4 derivatives and the reduction of dppe and dppp peroxo compounds to the dicarbonyl. Addition of CO2 to the peroxo compounds resulted in the formation of the peroxycarbonate species. The addition of SO2 to the peroxo compounds resulted in the formation of the dppm, dppe or dppp, dichloride starting materials. This was likely through oxidation of the SO2 to SO3, which further reacted to form sulfuric acid. The acid then reacted with the KCl present to generate the dichloride starting materials. Unfortunately, isolation of all the species was unsuccessful, therefore independent syntheses of the expect products were performed.