APPLICATION OF NMR TECHNIQUES TO ORGANOME TALLIC COMPOUNDS

Application of NMR techniques, especially a spin saturation transfer t echnique, to several organometallic compounds are reported with emphas is on compounds undergoing fluxional behavior with two-electron-three- centered bonds such as a M-H-C bond, i.e. agostic interaction, and a M -H-H bond, i.e. a molecular hydrogen ligand. C-13 spin saturation tran sfer experiments on the tautomers of H2Os3 (CO)10 (mu-CH2) and HOs (CO )10 (mu-CH3) show intramolecular hydrogen exchange to convert all of t he four isomers. H-1 spin saturation tranfer experiments on [RuH(diop) 2]PF6 show intramolecular hydrogen exchange between the hydride ligand and an aliphatic proton, presumably involving an agostic interaction, of the phosphine ligand. H-1 spin saturation transfer experiments on [RuH(eta2-H-2)(dppp)2]PF6 show intramolecular hydrogen exchange betwee n the molecular hydrogen and the hydride ligand. Application of isotop ic perturbation of resonance to agostic interaction is mentioned as a method to show the presence of a proton of an agostic interaction unde rgoing a rapid exchange.