Synthesis, characterization and hindered rotation of triosmium clusters (μ-H)Os3(CO)10L[ON(CF3)2] [L CO, CH3CN and PhCN]

Abstract

Bis(trifluoromethyl)nitroxyl radical reacts with H2OS3(CO)10L (L CH3CN, PhCN) to afford the stable derivatives (μ-H)Os3(CO)10L[ON(CF3) 2] in which single crystal X-ray structural analysis reveals that the (CF3)2 NO moiety assumes an axial terminal position. Variable-temperature 19F NMR spectra suggest that rotations of the (CF3)2N moiety about the OsO bond are hindered due to its proximity to the neighbouring CO groups. The activation energies were estimated from the coalescence temperatures. © 1992.