Novel high-yield method for the synthesis of [Os-3(CO)(10)(mu-H)(mu-OSiR2R')] species and X-ray characterization of [Os-3(CO)(10)(mu-H)(mu-OSiPh2OSiPh2OH)] and [Os-3(CO)(10)(mu-H)(mu-OSiPh2OH)], first molecular models of osmium surface species anchored to vicinal and geminal surface silanols

The easy replacement of the hydroxy ligand in [Os-3(CO)(10)(mu-H)(mu-OH)] b y siloxy ligands affords a high-yield procedure to model compounds of the t ype [Os-3(CO)(10)(mu-H)(mu-OSiR2R')] (R = Et, Ph; R' = Et, Ph, OH, OSiPh2OH ), a springboard to better understand the reactivity of osmium carbonyl spe cies on the silica surface. The new clusters [Os-3(CO)(10)(mu-H)(mu-OSiPh2O H)] and [Os-3(CO)(10)(mu-H)(mu-OSiPh2OSiPh2OH)], characterized by X-ray cry stallography, represent the first molecular models of silica-anchored [Os-3 (CO)(10)(mu-H)(mu-OSi=)] having a ligand that mimics surface geminal and vi cinal silanols, respectively.