Bis[N-benzyl-2-(quinolin-8-yloxy)acetamide]dichloridocopper(II) acetonitrile solvate monohydrate

In the title complex, [CuCl2(C18H16N2O2)2]·CH3CN·H2O, the six-coordinated Cu atom is in a distorted octahedral geometry with the donor centers of two O atoms and two N atom from two bidentate ligands, and two chloride ions. In the crystal, pairs of intermolecular N—H⋯ Cl hydrogen bonds form centrosymmetric dimers and intermolecular O—H⋯ O hydrogen bonds between the ligand and the uncoordinated water molecules link the dimers into chains parallel to the c axis.

In the title complex, [CuCl 2 (C 18 H 16 N 2 O 2 ) 2 ]ÁCH 3 CNÁH 2 O, the six-coordinated Cu atom is in a distorted octahedral geometry with the donor centers of two O atoms and two N atom from two bidentate ligands, and two chloride ions. In the crystal, pairs of intermolecular N-HÁ Á Á Cl hydrogen bonds form centrosymmetric dimers and intermolecular O-HÁ Á Á O hydrogen bonds between the ligand and the uncoordinated water molecules link the dimers into chains parallel to the c axis.

Comment
The luminescent properties of the lanthanide complexes with amide type ligands have been investigated in our previous work (Wu, Yuan et al., 2006;Wu et al., 2008). As part of our ongoing studies of the amide type ligands, the title complex was synthesized and characterized by X-ray diffraction.
As shown in Fig. 1, in the title complex, the six-coordinated Cu atom is in a distored octahedral geometry with the donor centers of two O atoms and two N atom from two ligands, and two chloride ions. It is worth noting that the O3 atom of the ligand also participates coordination since the distance of Cu1-O3 are 2.446 (3) Å. A longer Cu-O distance of 2.586 Å has been reported in complex [Cu 3 (L 1 ) 2 Cl 6 ].2DMF, where L 1 = 1,3,5-tris(2-pyridylmethoxyl)benzene (Wu, G. et al. 2006).
Other features of the structure are similar to those found in other sixcoordinate copper(II) complexes with similar donor sets (Al-Mandhary et al., 2002;Wu, Wang et al., 2006& Zhu et al., 2005. In the crystal, two intermolecular N-H··· Cl hydrogen bonds between two molecules create centrosymmetric dimers. and the dimers are linked into chains via the intermolecular O-H··· O hydrogen bonds between the ligand and the uncoordinated water molecules. Intermolecular N-H··· Cl hydrogen bonds are also present (Fig. 2). -benzyl-2-(quinolin-8-yloxy)acetamide (Wu, Yuan et al., 2006) (0.292 g, 1 mmol) was dissolved in acetonitrile (10 ml), then an acetonitrile solution (10 ml) containing copper(II) chloride dihydrate (0.179 g, 1 mmol) was added dropwise at room temperature. After stirring for 2 h, the mixture was filtered and set aside to crystallize at room temperature for 10 d, giving blue block crystals.

Refinement
The C31 phenyl ring was refined as rigid hexagon of 1.39 Å sides as there was a slight spread of C-C distances. The water H-atoms were located in a difference Fourier map and refined with an O-H distance restrain of 0.85 (2) Å. Other H atoms attached to C and N atoms were placed in calculated positions and treated using a riding-model approximation (C-H=0.93 for aromatic ring H atoms with U iso (H)=1.2Ueq(C); N-H=0.86 with U iso (H)=1.5Ueq(N)). Fig. 1. The molecular structure shown with 30% probability displacement ellipsoids.

Special details
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 > σ(F 2 ) is used only for calculating Rfactors(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.