Schutte M, Visser H G, Roodt A
Department of Chemistry, University of the Free State, PO Box 339, Bloemfontein, 9301, South Africa.
Acta Crystallogr Sect E Struct Rep Online. 2012 Nov 1;68(Pt 11):m1359-60. doi: 10.1107/S1600536812041700. Epub 2012 Oct 13.
In the title compound, [Re(2)(CH(3)O)(2)(CO)(6)(C(4)H(6)N(3)O)], the two Re(I) atoms are linked by a methoxo and methanolato bridge, as well as by a creatinine ligand that coordinates in a bidentate fashion. Three fac-carbonyl ligands occupy the rest of the slightly distorted octa-hedral geometry around each Re(I) atom. The bridging methanolato and methoxo ligands are bent out of the Re(2)O(2) plane by 49.2 (4) and 47.8 (3)° respectively. This is normally associated with a methanolato-bridging-type coordination rather that the more planar methoxo-type bridging. Furthermore, the creatinine bridging molecule is very slightly distorted from the Re(2)N(2)C plane, indicating that the pyrazolo N atom bonded to the Rh(I) atom is not protonated. Charge balance can thus only be attained if one assumes a positional disorder for the methanolato/methoxo H atom. All attempts to locate disordered protons around these O atoms were unsuccessful. Four hydrogen bonds, one N-H⋯O and three C-H⋯O, are observed in the structure. The mol-ecules pack in a head-to-head and tail-to-tail fashion when viewed along the c axis, in alternating columns.
