Multinuclear NMR and Thermal Studies of New Silver(I)Silylated Carboxylates with Triphenylphosphine

摘要

Me_3SiCH_2COOAg,[Ag(Me_3SiCH_2COO)(PPh_3)] and [Ag(Me_3SiCH_2CH_2COO)(PPh_3)] were prepared and characterized in solution by ~1H,~(13)C,~(29)Si,~(31)P and ~(29)Si,~(31)P CPMAS NMR.Spectral analysis suggests bidentate bridging carboxylates and monodentately bonded PPh_3 in solution and in the solid state.Two crystallographically inequivalent molecules of PPh_3 appeared in the solid state,what is evident from ~(31)P CPMAS NMR.Thermal studies of both complexes demonstrate two stage decomposition process(exothermic followed by endothermic)with formation of metallic silver in the range 48_3-548 K.TGA/IR and MS studies of Me_3SiCH_2COOAg and [Ag(Me_3SiCH_2COO)(PPh_3)] revealed volatile products of decomposition(CO_2,Me_3Si-)and recombination reactions such as(Me_3SiCH_2CO)_2O,(Me_3Si)_2O.The mechanism of complexes thermal decomposition is proposed.