Crystal and Molecular Structures of Two Isomers for Chlorobis-(2-methyl-8-quinolinolato)nitrosylruthenium(III)

Two isomers of [RuCl(2mqn)2(NO)] (2mqn=2-methyl-8-quinolinolate ion) were isolated and their crystal structures were determined by X-ray diffraction. In both the isomers, the Cl atom lies cis to the NO group and the O atom of one of the quinolinolato ligands lies trans to the NO group. One of the two isomers, (1), is in cis(O,O) and trans(N,N) configuration for the two quinolinolato ligands, another, (2), being in cis(O,O) and cis(N,N). Crystal data: 1, space group P21⁄c (monoclinic), a=7.412(1), b=27.241(6), c=9.752(1) Å, β=105.49(1)°; 2, space group P21⁄c (monoclinic), a=7.157(2), b=20.205(4), c=13.359(3) Å, β=107.70(2)°. The final R values for 1 and 2 are 0.044 for non-hydrogen atoms and 0.037 for all the atoms, respectively. The coordination geometries of 1 and 2 are distorted octahedron. The interatomic distances are qualitatively discussed on the basis of π- and σ-bonding abilities of the NO group, the Cl, and the coordinating atoms, N and O, of the quinolinolato ligands.