SYNTHESES AND CHARACTERISATION OF , 2-H)Os3(CO)10(μ2-PRH)> (R=C6H5, p-CH3OC6H4, C6H11) AND 2-H)2Os3(CO)9(μ2-PR)> (R=C6H5, C6H11). INTERCONVERSION OF CLUSTER-BOUND PHOSPHINE AND PHOSPHIDO LIGANDS. CRYSTAL AND MOLECULAR STRUCTURES OF2-H).....

Article abstract of DOI:10.1016/S0022-328X(00)82289-5

Monoorganophosphines react with Os3(CO)12 in presence of trimethylamine oxide to give the phosphine-substituted cluster and the phosphido-bridged hydrido cluster <(μ2-H)Os3(CO)10(μ2-PRH)> (R=C6H5, p-CH3OC6H4, C6H11).The thermolysis of gave, under different conditions, <(μ2-H)Os3(CO)10(μ2-PRH)> and <(μ2-H)2Os3(CO)9(μ3-PR)>, and the thermolysis of <(μ2-H)Os3(CO)10(μ2-PRH)> gave <(μ2-H)2Os3(CO)9(μ3-PR)> (R=C6H5, C6H11).All the compounds have been studied by IR, NMR (31P and 1H) and mass spectrometry.The structures of <(μ2-H)Os3(CO)10(μ2-P(C6H5)H> and <(μ2-H)2Os3(CO)9(μ3-PC6H5)> have been determined by X-ray crystallography.The results obtained for the system Os3(CO)12/PRH2 demonstrate a stepwise transformation of a terminally bonded PRH2 ligand to a doubly bridging μ2-PRH unit and finally to a triply bridging μ3-PR group by successive hydrogen transfer and CO substitution processes.