Bis(N-nitroso-N-pentylhydroxylaminato-κ2 O,O′)copper(II)

In the centrosymmetric title compound, [Cu(C5H11N2O2)2], the Cu2+ ion, located on an inversion centre (Wyckoff position 2b), is in a square-planar environment, surounded by four O atoms of the N—O groups of two N-nitroso-N-pentylhydroxylaminate ligands [Cu—O = 1.9042 (17) and 1.9095 (16) Å]. The hydroxylaminate monoanions are bidentate chelating ligands. The Cu2+ cations form stacks along [010], with intermolecular Cu⋯N contacts of 3.146 (2) and 3.653 (2) Å.

In the centrosymmetric title compound, [Cu(C 5

Experimental
The title compound was obtained in accordance with the previously published procedure (Zyuzin et al., 1997) with some modifications. A solution of n-pentylmagnesium chloride was prepared from magnesium (12.2 g, 0.5 mol) and 1-bromopentane (75.5 g, 0.5 mol) in the dry Et 2 O (0.5 L). The NO gas was bubbled through the solution under vigorous stirring and cooling at such a rate that NO was almost entirely absorbed. The reaction mixture temperature was maintained in the range 248 to 243 K. After the period of a rapid NO absorption (1 h), stirring was continued in an NO atmosphere for 0.5 h until the NO absorption was completed, with a gradual increase in temperature to 263 K. The reaction mixture was purged with Ar, treated with MeOH (100 mL), poured into ice (300 g) and acidified with 2 M H 2 SO 4 . The organic layer was separated, and the aqueous layer was extracted with Et 2 O (100 mL × 3). The combined extracts were washed with 50 mL 1 M NaOH and 50 mL H2O. The aqueous layer was neutralized with 2 M H 2 SO 4 until pH 4 and treated with 20 per cent CuSO 4 solution (120 g, 0.2 mol). The blue precipitate was washed with water, dried and crystallized from EtOH.

Refinement
The structure of of C 10 H 22 CuN 4 O 4 was solved by direct method and all non-hydrogen atoms were located and refined anisotropically. All the hydrogen atoms added using a riding model.

Figure 1
ORTEP view of C 10 H 22 CuN 4 O 4 with atom labeling scheme (displacement ellipsoids are drawn at the 50% probability level for non-hydrogen atoms). The second half of the molecule is generated by the symmetry operator 1-x, 1-y,1-z.

Figure 2
Mutual arrangement of neighboring complexes in a stack.