[2-(Dimethylamino)ethanol-κ2 N,O][2-(dimethylamino)ethanolato-κ2 N,O]iodidocopper(II)

The title compound, [Cu(C4H10NO)I(C4H11NO)], was obtained unintentionally as the product of an attempted synthesis of a Cu/Zn mixed-metal complex using zerovalent copper, zinc(II) oxide and ammonium iodide in pure 2-(dimethylamino)ethanol, in air. The molecular complex has no crystallographically imposed symmetry. The coordination geometry around the metal atom is distorted square-pyramidal. The equatorial coordination around copper involves donor atoms of the bidentate chelating 2-(dimethylamino)ethanol ligand and the 2-(dimethylamino)ethanolate group, which are mutually trans to each other, with four approximately equal short Cu—O/N bond distances. The axial Cu—I bond is substantially elongated. Intermolecular hydrogen-bonding interactions involving the –OH group of the neutral 2-(dimethylamino)ethanol ligand to the O atom of the monodeprotonated 2-(dimethylamino)ethanolate group of the molecule related by the n-glide plane, as indicated by the O⋯O distance of 2.482 (12) Å, form chains of molecules propagating along [101].

The title compound, [Cu(C 4 H 10 NO)I(C 4 H 11 NO)], was obtained unintentionally as the product of an attempted synthesis of a Cu/Zn mixed-metal complex using zerovalent copper, zinc(II) oxide and ammonium iodide in pure 2-(dimethylamino)ethanol, in air. The molecular complex has no crystallographically imposed symmetry. The coordination geometry around the metal atom is distorted squarepyramidal. The equatorial coordination around copper involves donor atoms of the bidentate chelating 2-(dimethylamino)ethanol ligand and the 2-(dimethylamino)ethanolate group, which are mutually trans to each other, with four approximately equal short Cu-O/N bond distances. The axial Cu-I bond is substantially elongated. Intermolecular hydrogen-bonding interactions involving the -OH group of the neutral 2-(dimethylamino)ethanol ligand to the O atom of the monodeprotonated 2-(dimethylamino)ethanolate group of the molecule related by the n-glide plane, as indicated by the OÁ Á ÁO distance of 2.482 (12) Å , form chains of molecules propagating along [101].

Related literature
For background to the synthesis, see: Vinogradova et al. (2002). Buvaylo et al. (2009Buvaylo et al. ( , 2011. Elongation of the axial Cu-I bond is common in this kind of compound, see: Wells (1986 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Johnson (1976); software used to prepare material for publication: WinGX (Farrugia, 1999 (Vinogradova et al., 2002). Reactions employing elemental copper and aminoalcohol allow in situ formation of the metal aminoalkoxo species -key building blocks that can subsequently self-assemble with other metal centres present in the reaction vessel (Buvaylo et al., 2009;Buvaylo et al., 2011). The title compound was isolated from the solution obtained by reacting copper powder and zinc oxide with ammonium iodide in pure 2-(dimethylamino)ethanol. It can be considered as an intermediate, a building block that failed self-organization with another metal species produced in the reaction medium. To the best of our knowledge the title compound has not been structurally characterized.
The molecular complex has no crystallographically imposed symmetry (Fig. 1). The coordination geometry around the metal atom is distorted square pyramidal. The equatorial coordination around Cu(1) involves donor atoms of bidentate chelating 2-(dimethylamino)ethanol and 2-(dimethylamino)ethanolato group, which are mutually trans to each other, with four approximately equal short distances. The axial Cu(1)-I(1) bond is substantially elongated [2.928 (2) Å], and it is common for this kind of compounds (Wells, 1986).

Experimental
Copper powder (0.16 g, 2.5 mmol), ZnO (0.20 g, 2.5 mmol), NH 4 I (1.45 g, 10 mmol), HMe 2 Ea (15 ml) were heated to 323-333 K and magnetically stirred until total dissolution of the copper and ZnO was observed (95 min). The resulting blue solution was filtered and allowed to stand at room temperature. Green-blue microcrystals of the title compound were formed after one day. They were collected by filter-suction, washed with dry Pr i OH and finally dried in vacuo (yield: 0.23 g).

Refinement
The non-hydrogen atoms were refined anisotropically. The hydrogen atom on O2 atom was located and its position constrained with the isotropic displacement parameter allowed to refine. Other hydrogen atoms were placed at idealized positions (C-H = 0.95 Å, U iso H = 1.20U eq C for CH 2 , 1.5U eq C for CH 3 ) and not refined. ; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Johnson (1976); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figure 1
Molecular structure of the complex with the numbering scheme (the non-hydrogen atoms shown as 20% thermal ellipsoids).

Figure 2
Hydrogen-bonding interactions between Cu(Me 2 Ea)(HMe 2 Ea)I molecules within a polymeric chain.

[2-(Dimethylamino)ethanol-κ 2 N,O][2-(dimethylamino)ethanolato-κ 2 N,O]iodidocopper(II)
Crystal data [Cu(C 4  where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max = 0.013 Δρ max = 1.80 e Å −3 Δρ min = −0.83 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.