Di-μ-oxido-bis({2,2′-[ethane-1,2-diylbis(nitrilomethanylylidene)]diphenolato}titanium(IV)) chloroform disolvate

In the title compound, [Ti2(C16H14N2O2)2O2]·2CHCl3, the TiIV atom in the centrosymmetric complex has a distorted octahedral N2O4 coordination environment and is linked via two μ2-oxido bridges into a dinuclear centrosymmetric complex, with a Ti⋯Ti separation of 2.7794 (8) Å. In the salen (N,N′-ethylenebis(salicylimine)) ligand, the two salicylimine units make a dihedral angle of 45.31 (5)°. The complex molecules are stacked parallel to [100], forming channels in which the solvent chloroform molecules are located. C—H⋯O hydrogen-bonding interactions between the complex molecules and the solvent molecules consolidate the crystal packing.

In the title compound, [Ti 2 (C 16 H 14 N 2 O 2 ) 2 O 2 ]Á2CHCl 3 , the Ti IV atom in the centrosymmetric complex has a distorted octahedral N 2 O 4 coordination environment and is linked via two 2 -oxido bridges into a dinuclear centrosymmetric complex, with a TiÁ Á ÁTi separation of 2.7794 (8) Å . In the salen (N,N 0 -ethylenebis(salicylimine)) ligand, the two salicylimine units make a dihedral angle of 45.31 (5) . The complex molecules are stacked parallel to [100], forming channels in which the solvent chloroform molecules are located. C-HÁ Á ÁO hydrogen-bonding interactions between the complex molecules and the solvent molecules consolidate the crystal packing.
This work was partially supported by a grant from the President of the Russian Federation to support the research of young Russian scientists and doctors (MD-3634.2012.3).

Comment
As a part of our investigation on the chemistry of titanium complexes based on tridentate or tetradentate ligands (Zaitsev et al., 2006(Zaitsev et al., , 2008  that crystallizes with two chloroform solvent molecules. For general background to the chemistry of titanium complexes based on salen-type ligands, see: Gupta & Sutar (2008).
In the crystal, solvent chloroform molecule are linked via C-H···O hydrogen bonding interactions with the main molecule ( Table 1). The solvent molecules fill channels spreading parallel to [100] (Fig. 2). The adjacent titanium complexes are connected by T-shaped C-H···π interactions. However, no π···π-stacking interactions are observed in this structure.

Experimental
The title compound was obtained from reaction of equimolar amounts of Ti(O-iPr) 4 and salen in chloroform as a solid which is insoluble in common organic solvents. The crystals suitable for X-Ray analysis crystallized from the reaction mixture.

Refinement
All hydrogen atoms were placed in calculated positions and refined using a riding model with C-H = 1.00 Å and U iso (H) = 1.2U eq (C) for chloroform molecule; C-H = 0.99 Å and U iso (H) = 1.2U eq (C) for methylene groups; C-H = 0.95 Å and U iso (H) = 1.2U eq (C) for sp 2 carbon atoms.

Special details
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s 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 > σ(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.