[Bis(4-methyl-1,3-thiazol-2-yl-κN)methane]tricarbonyldichloridotungsten(II)

The title compound, [WCl2(C9H10N2S2)(CO)3], is a heptacoordinate tungsten(II) complex with a capped–octahedral coordination sphere in which one CO ligand caps a face formed by a chloro ligand and the two other carbonyls. The chloro ligands are mutually trans positioned at an angle of 156.98 (7)°. The chelating bis(4-methyl-1,3-thiazol-2-yl)methane ligand coordinates with the imine N atoms. In the crystal, molecules are linked into chains parallel to [201] by weak C—H⋯O contacts between the CH2 group of the bis(4-methylthiazol-2-yl)methane ligand and the O atom of the capping CO group.

The title compound, [WCl 2 (C 9 H 10 N 2 S 2 )(CO) 3 ], is a heptacoordinate tungsten(II) complex with a capped-octahedral coordination sphere in which one CO ligand caps a face formed by a chloro ligand and the two other carbonyls. The chloro ligands are mutually trans positioned at an angle of 156.98 (7) . The chelating bis(4-methyl-1,3-thiazol-2-yl)methane ligand coordinates with the imine N atoms. In the crystal, molecules are linked into chains parallel to [201] by weak C-HÁ Á ÁO contacts between the CH 2 group of the bis(4methylthiazol-2-yl)methane ligand and the O atom of the capping CO group.
Crystal and molecular structures of seven-coordinate complexes of the type [WX 2 (CO) 3 (RCN) 2 ] (RCN is an organic nitrile) have been reported by Baker et al. (1986Baker et al. ( , 1996Baker et al. ( , 2000 and Drew et al. (1988Drew et al. ( , 1995. The W-N bond distances in these nitrile complexes are shorter than those found in the title compound while other geometrical parameters are similar. The nitrile complexes also exhibit capped-octahedral geometry with trans-disposed iodo ligands. They possess a mirror plane that bisects the molecule while in the title compound the whole molecule is asymmetric; the position of the carbonyl ligands with respect to the bidentate bis(thiazolyl)methane is incompatible with C s symmetry. Hillhouse et al. (1982) report coordination of a tetraarylphosphazide (PhNNNPPh 3 ) to a dibromotricarbonyltungsten fragment which is different from the title compound and the structures mentioned here in that it contains a set of cis-bromo ligands, possibly caused by the smaller bite angle of the tetraarylphosphazide (N-W-N angle of 56.7 (2)° as opposed to the N1-W1-N2 angle measuring 83.3 (2)° in the title compound). Finally, a geometrically very similar complex to the one reported here but utilizing a bis(azolyl)methane ligand was prepared by Shiu et al., (1990) [WBr 2 (CO) 3 (CH 2 R 2 )] (R = 3,4,5-trimethyl-1H-pyrazol-1-yl-κN 2 ).
The significantly longer W1-Cl2 bond (2.528 (2)Å) in the title compound is adjacent to the capping CO ligand while the W1-Cl1 bond is undisturbed by a capping ligand and measures 2.4708 (17)

Refinement
All H atoms were positioned geometrically (C-H = 0.95Å, 0.99Å and 0.98Å for CH, CH 2 and CH 3 groups, respectively) and constrained to ride on their parent atoms; U iso (H) values were set at 1.2U eq (C) for CH-and CH 2 -groups and 1.5U eq (C) for CH 3 -groups.
The maximum residual electron density of 3.92 e×Å -3 is located 0.79Å near W1. Fig. 1. Molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. Hydrogen atoms are shown as spheres of arbitrary radius.