Coordination chemistry of a model for the GP cofactor in the Hmd hydrogenase: hydrogen-bonding and hydrogen-transfer catalysis.
Cp(*)M(2+) complexes (M = Rh, Ir; Cp(*) = C(5)Me(5)) are described for 6-(carboxymethyl)-4-methyl-2-hydroxypyridine (cmhpH(2)), an analogue of the guanylylpyridone cofactor in the hydrogenase Hmd. Three findings indicate that Cp(*)M(Hcmhp)(+) stabilizes the binding of hydrogen-bond acceptors to the sixth coordination site: (i) water binds in preference to Cl-, (ii) the adduct Cp(*)Rh(cmhp)(2-hydroxypyridine) exhibits a very short intramolecular hydrogen bond (r(o-o) = 2.38 A; (1)H NMR delta(H) 17.2), and (iii) Cp(*)Ir(cmhpH)Cl efficiently catalyzes the dehydrogenation of PhCH(OH)Me to PhC(O)Me.
Royer
Aaron M
AM
Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
Rauchfuss
Thomas B
TB
Wilson
Scott R
SR
D002384:Catalysis; D006860:Hydrogen Bonding; D006864:Hydrogenase / Q000737:chemistry*; D008958:Models, Molecular
D006864:Hydrogenase