Bis[μ-N′-(2-oxidobenzylidene)thiophene-2-carbohydrazidato]bis[dimethanolnickel(II)]

In the crystal structure of the centrosymmetric binuclear title complex, [Ni2(C12H8N2O2S)2(CH3OH)4], there are intermolecular O—H⋯O, O—H⋯N and O—H⋯S hydrogen bonds. These help to stabilize the structure and link the molecules, forming a three-dimensional network structure. The Ni2+ cation exists in a slightly distorted octahedral NiNO5 coordination environment. The thiophene rings are disordered over two equivalent conformations with occupancies of 0.881 (3) and 0.119 (3).

In the crystal structure of the centrosymmetric binuclear title complex, [Ni 2 (C 12 H 8 N 2 O 2 S) 2 (CH 3 OH) 4 ], there are intermolecular O-HÁ Á ÁO, O-HÁ Á ÁN and O-HÁ Á ÁS hydrogen bonds. These help to stabilize the structure and link the molecules, forming a three-dimensional network structure. The Ni 2+ cation exists in a slightly distorted octahedral NiNO 5 coordination environment. The thiophene rings are disordered over two equivalent conformations with occupancies of 0.881 (3) and 0.119 (3).

Related literature
For the structure of the related Cu complex, see: Lu et al. (2006). For the synthesis of the ligand, see: Wu et al. (2004).

Comment
The structure of [Cu(C 12 H 9 N 2 O 2 S)Cl].H 2 O (II), which is closely related to the title comlex has already been reported (Lu et al., 2006). In this article, we report the crystal structure of the realted nickel complex, I.

Experimental
The ligand was synthesized according to the method of Wu et al., (2004). NiCl 2 (1 mmol) and the ligand were separately dissolved in 20 ml methanol and the resulting solutions mixed slowly, stirred at room temperature for one hour, and then filtered. The filtrate was allowed to stand at room temperature for ten days, yielding deep-blue crystals of the title compound by slow evaporation.

Refinement
The C-bound H atoms were included in the riding model approximation with C-H = 0.93 -0.96 Å, all these H atoms included in the final refinement. The U iso of each H atom = 1.2U eq (C) [1.5U eq (C) for CH 3 ]. The methanol H atoms were refined isotropically. Fig. 1. The molecular structure (at 30% probability) of the title compound.

Special details
Experimental. 2011-03-01 # Formatted by IUCr publCIF system Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.
Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > 2sigma(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.