Osmium(VI) Nitrido Complexes with Perfluorinated Alcoholate Ligands: Expanding Ligand Scope through a Simple Silver Oxide-Mediated Synthesis Route

Abstract

The coordination of perfluorinated alcohols toward an osmium(VI) nitrido center is described. Herein, [NBu4][OsNCl4] is reacted with hexafluoroacetone hydrate (HFA), perfluoropinacol (PFP), or pentafluorophenol (C6F5OH) in the presence of Ag2O to obtain the stable complexes [NBu4][Os(N)(O2C(CF3)2)2] (1), [NBu4][Os(N)(O2C2(CF3)4)2] (2), [NBu4][Os(N)(OC6F5)4] (3), and [NBu4][Os(N)(Cl)2(O2C(CF3)2)] (4) in overall good yields. These complexes represent rare examples of Os(VI) nitrido complexes that carry four O-donor ligands, as no examples have been reported for perfluorinated alcoholates so far. Complexes 1 and 4 extend the coordination chemistry of the otherwise underrepresented O2C(CF3)2 ligand. The latter offers the potential for further functionalization of the osmium(VI) nitrido complex through substitution of the remaining chloride ligands. The compounds are fully characterized, and the crystal structures of compounds 1, 2, and 3 are analyzed.