title: Hydrogen-mediated metal-carbon to metal-boron bond conversion in metal-carboranyl complexes.
abstract: A hydrogen-mediated Ru-C to Ru-B bond conversion was observed experimentally and supported by the theoretical calculations. Treatment of [eta(5):sigma(C)-Me(2)C(C(5)H(4))(C(2)B(10)H(10))]Ru(COD) (1) bearing a Ru-C(cage) sigma bond with PR(3) in the presence of H(2) gave Ru-B(cage) bonded complexes [eta(5):sigma(B)-Me(2)C(C(5)H(4))(C(2)B(10)H(10))]RuH(2)(PR(3)) (R = Cy (2), Ph (3)) (sigma(C): Ru-C(cage) sigma bond; sigma(B): Ru-B(cage) sigma bond). Complex 3 was converted to [eta(5):sigma(B)-Me(2)C(C(5)H(4))(C(2)B(10)H(10))]Ru(L(2)) in the presence of L(2) (L(2) = dppe (4), PPh(3)/P(OEt)(3) (5), PPh(3)/pyridine (6)) via liberation of H(2) upon heating. These complexes were fully characterized by various spectroscopic techniques, elemental analyses, and single-crystal X-ray diffraction studies. DFT calculations show that this conversion process is both kinetically and thermodynamically favorable and requires involvement of a hydride ligand.
authors.affiliation: Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
authors.forename: Dongmei
authors.initials: D
authors.lastname: Liu
authors.forename: Li
authors.initials: L
authors.lastname: Dang
authors.forename: Yi
authors.initials: Y
authors.lastname: Sun
authors.forename: Hoi-Shan
authors.initials: HS
authors.lastname: Chan
authors.forename: Zhenyang
authors.initials: Z
authors.lastname: Lin
authors.forename: Zuowei
authors.initials: Z
authors.lastname: Xie