Bis[N,N-bis(2-hydroxyethyl)glycinato]cobalt(II)

The asymmetric unit of the title compound, [Co(C6H12NO4)2], contains one half-molecule with the CoII ion situated on an inversion center. Intermolecular O—H⋯O hydrogen bonds generate a three-dimensional hydrogen-bonding network, which consolidates the crystal packing.

The asymmetric unit of the title compound, [Co(C 6 H 12 NO 4 ) 2 ], contains one half-molecule with the Co II ion situated on an inversion center. Intermolecular O-HÁ Á ÁO hydrogen bonds generate a three-dimensional hydrogen-bonding network, which consolidates the crystal packing.
In (I) (Fig. 1), the Co(II) ions are located on the inversion centers and are coordinated by two L ligands forming an octahedral enviromental geometry with four oxygen and two nitrogen atoms. The bond lengths are: Co1-N1 = 2.172 (3) Å, Co1-O2 = 2.088 (3) Å and Co1-O4 = 2.046 (2) Å. Though ML 2 complexes (M = Co, Ni, Cu) have similar structures, there are some differences. The Co and Ni centers are in a regular octahedron coordinated geometry, while the Cu center has an elongated octahedral coordination with two hydroxy atoms in axial positions.
Red crystals of the title complex were collected after the bomb was allowed to cool to room temperature.Yield 20% based on metal salt.

Refinement
C-bound H atoms were included in calculated positions and treated as riding on their parent atoms, with C-H = 0.93Å and U iso (H) = 1.2U eq (C). Hydroxy H atoms were located on difference Fourier maps, but placed in idealized positions (O-H = 0.85Å) and refined as riding, with U iso (H) = 1.2U eq (O). Fig. 1. The molecular structure of the title complex. Displacement ellipsoids are drawn at the 30% probability level. H atom have been omitted for clarity. Symmetry code: (A) -x+1, -y-1, -z+1.

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq