Dimethanolbis[4,4,5,5-tetramethyl-2-(5-methylimidazol-4-yl)-2-imidazoline-1-oxyl-3-oxide-κ2 O,N]cobalt(II) diperchlorate

In the mononuclear title complex, [Co(C11H17N4O2)2(CH3OH)2](ClO4)2, the cobalt(II) atom lies on a symmetry centre and is coordinated by two O,N-bidentate ligands and two trans-arranged O atoms of the methanol molecules in a slightly distorted octahedral geometry. In the crystal structure, cations and anions are linked by N—H⋯O and O—H⋯O hydrogen bonds into layers parallel to the bc plane.

In the mononuclear title complex, [Co(C 11 H 17 N 4 O 2 ) 2 -(CH 3 OH) 2 ](ClO 4 ) 2 , the cobalt(II) atom lies on a symmetry centre and is coordinated by two O,N-bidentate ligands and two trans-arranged O atoms of the methanol molecules in a slightly distorted octahedral geometry. In the crystal structure, cations and anions are linked by N-HÁ Á ÁO and O-HÁ Á ÁO hydrogen bonds into layers parallel to the bc plane.

Experimental
Crystal data [Co(C 11 Table 1 Hydrogen-bond geometry (Å , ). Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: publCIF (Westrip, 2009). acting as useful paramagnetic building blocks have been extensively used to assemble molecular magnetic materials, because many of them are good stable spin carriers even when coordinated to metal ions. Various substitutions on radical ligands can lead to large change in not only coordination modes but also electronic behaviours, so a large number of investigations on various properties of metal-radicals complexes have been carried out and aroused intense interest and far-ranging studies (Chang et al., 2009;Zhang et al., 2007;Omata et al., 2001;Fokin et al., 2004;Wang et al., 2005). In this article, we report the synthesis and crystal structure of a novel cobalt(II) complex with the nitronyl nitroxide radical.
The crystal structure of the title compound is shown in Figure. (Table   1) into layers parallel to the bc plane.

Refinement
The H atoms were positioned geometrically and refined using a riding-model approximation, with C-H = 0.93-0.96 Å, N-H = 0.86 Å, O-H = 0.85 Å, and with U iso (H) = 1.2 U eq (C, N) or 1.5 U eq (C, O) for hydroxy and methyl H atoms.
supplementary materials sup-2 Figures Fig. 1. The molecular structure of the title compound with the atom-labeling scheme. Displacement ellipsoids are drawn at the 30% probability level. Unlabelled atoms are generated by the symmetry operation (-x+1,-y+1,-z+1).
Crystal data [Co(C 11