{2-[(2-Aminocyclohexyl)iminomethyl]phenolato}dioxidovanadium(V)

In the title dioxidovanadium complex, [V(C13H17N2O)O2], the VV atom is in a square-based pyramidal coordination: the basal plane is defined by the phenolate O, imine N and amine N atoms of the tridentate Schiff base ligand, and by one oxide O atom. The apical position is occupied by the other oxide O atom. In the crystal, molecules are connected by N—H⋯O and N—H⋯(O,O) hydrogen bonds, forming a tetramer.

In the title dioxidovanadium complex, [V(C 13
In the title dioxovanadium complex, Fig. 1, the V atom is in a square pyramidal coordination. The basal plane of the square pyramid is defined by one phenolate O, one imine N, and one amine N atoms of a Schiff base ligand, and by one oxo O atom. The apical position of the square pyramid is occupied by the other oxo O atom. The bond lengths (Table 1) are comparable to those observed in similar oxovanadium complexes (Xie et al., 2004;Jing et al., 2005;Huo et al., 2004). In the crystal, adjacent molecules are linked through N-H···O and N-H···(O,O) hydrogen bonds (Table 2) to form a tetramer (Fig. 2).

Experimental
To a MeOH solution (30 ml) of salicylaldehyde (0.122 g, 1.0 mmol) was added a MeOH solution (20 ml) of cyclohexane-1,2-diamine (0.114 g, 1.0 mmol) with stirring. To the above mixture was added a MeOH solution (10 ml) of VO(acac) 2 (0.265 g, 1.0 mmol) with stirring. The mixture was refluxed for 1 h, affording a clear yellow solution. This was allowed to stand at room temperature for a week and block-shaped single crystals were obtained by slow evaporation.

Refinement
H atoms attached to C and N atoms were placed in geometrically idealized positions with Csp 2 -H = 0.93 Å, Csp 3 -H = 0.97-0.98 Å, N-H = 0.90 Å, and constrained to ride on their parent atoms, with U iso (H) = 1.2U eq (C and N). Apparent disorder was evident in the cyclohexyl ring.  The structure of the title compound, with displacement ellipsoids drawn at the 30% probability level for Non-H atoms.

Figure 2
The tetrameric unit in the crystal, with hydrogen bonds shown as double-dashed lines.

{2-[(2-Aminocyclohexyl)iminomethyl]phenolato}dioxidovanadium(V)
Crystal data [V(C 13  where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.44 e Å −3 Δρ min = −0.30 e Å −3 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.