Five-coordinate pentafluorobenzothiolate osmium(IV) complexes [Os(SC6F5)4(P(C6H4X-4)3)] (XÂ =Â OCH3, CH3, F, Cl or CF3): Solid and solution structural characterization

X-ray diffraction studies of [Os(SC6F5)4(P(C6H4X-4)3)] exhibit a tbp coordination with the three eq-C6F5-rings towards the ax-thiolate (isomers “3-up”). NMR studies at r.t. reveal in addition the “2-up, 1-down” isomer with two eq-C6F5-rings towards the ax-thiolate and the third eq-C6F5-ring towards the phosphane. At low temperatures are observed restricted rotations about specific bonds in these molecules.