title: pH-Dependent isotope exchange and hydrogenation catalysed by water-soluble NiRu complexes as functional models for [NiFe]hydrogenases.
abstract: The pH-dependent hydrogen isotope exchange reaction between gaseous isotopes and medium isotopes and hydrogenation of the carbonyl compounds have been investigated with water-soluble bis(mu-thiolate)(mu-hydride)NiRu complexes, Ni(II)(mu-SR)(2)(mu-H)Ru(II) {(mu-SR)(2) = N,N'-dimethyl-N,N'-bis(2-mercaptoethyl)-1,3-propanediamine}, as functional models for [NiFe]hydrogenases. In acidic media (at pH 4-6), the mu-H ligand of the Ni(II)(mu-SR)(2)(mu-H)Ru(II) complexes has H(+) properties, and the complexes catalyse the hydrogen isotope exchange reaction between gaseous isotopes and medium isotopes. A mechanism of the hydrogen isotope exchange reaction between gaseous isotopes and medium isotopes through a low-valent Ni(I)(mu-SR)(2)Ru(I) complex is proposed. In contrast, in neutral-basic media (at pH 7-10), the mu-H ligand of the Ni(II)(mu-SR)(2)(mu-H)Ru(II) complexes acts as H(-), and the complexes catalyse the hydrogenation of carbonyl compounds.
authors: Center for Future Chemistry, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan.
authors: Bunsho
authors: B
authors: Kure
authors: Takahiro
authors: T
authors: Matsumoto
authors: Koji
authors: K
authors: Ichikawa
authors: Shunichi
authors: S
authors: Fukuzumi
authors: Yoshiki
authors: Y
authors: Higuchi
authors: Tatsuhiko
authors: T
authors: Yagi
authors: Seiji
authors: S
authors: Ogo
mesh_terms: D002384:Catalysis; D006863:Hydrogen-Ion Concentration; D006864:Hydrogenase / Q000737:chemistry* / Q000378:metabolism*; D006865:Hydrogenation; D007554:Isotopes / Q000737:chemistry; D008954:Models, Biological; D008956:Models, Chemical; D009532:Nickel / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D011522:Protons; D012428:Ruthenium / Q000737:chemistry*; D012995:Solubility; D014867:Water / Q000737:chemistry*
chemical_list: D007554:Isotopes; D009942:Organometallic Compounds; D011522:Protons; D014867:Water; D009532:Nickel; D012428:Ruthenium; C043296:nickel-iron hydrogenase; D006864:Hydrogenase