A Capped Octahedral MHC6 Compound of a Platinum Group Metal

A MHC6 complex of a platinum group metal with a capped octahedral arrangement of donor atoms around the metal center has been characterized. This osmium compound OsH{kappa(2)-C,C-(PhBIm-C6H4)}(3), which reacts with HBF4 to afford the 14e(-) species [Os{kappa(2)-C,C-(PhBIm-C6H4)}(Ph(2)BIm)(2)]BF4 stabilized by two agostic interactions, has been obtained by reaction of OsH6(PiPr(3))(2) with N,N'-diphenylbenzimidazolium chloride ([Ph(2)BImH]Cl) in the presence of NEt3. Its formation takes place through the C,C,C-pincer compound OsH2{kappa(3)-C,C,C-(C6H4-BIm-C6H4)}(PiPr(3))(2), the dihydrogen derivative OsCl{kappa(2)-C,C-(PhBIm-C6H4)}(eta(2)-H-2)(PiPr(3))(2), and the five-coordinate osmium(II) species OsCl{kappa(2)-C,C-(PhBIm-C6H4)}(PiPr(3))(2).