(Acetonitrile)[bis(2-pyridylmethyl)amine]bis(perchlorato)copper(II)

In the title compound, [Cu(ClO4)2(C12H13N3)(C2H3N)], the CuII atom is six-coordinate in a Jahn–Teller distorted octahedral geometry, with coordination by the tridentate chelating ligand, an acetonitrile molecule, and two axial perchlorate anions. The tridentate ligand bis(2-pyridylmethyl)amine chelates meridionally and equatorially while an acetonitrile molecule is coordinated at the fourth equatorial site. The two perchlorate anions are disordered with site occupancy factors of 0.72/0.28. The amine H is involved in intramolecular hydrogen bonding to the perchlorate O atoms and there are extensive but weak intermolecular C—H⋯O interactions.

In the title compound, [Cu(ClO 4 ) 2 (C 12 H 13 N 3 )(C 2 H 3 N)], the Cu II atom is six-coordinate in a Jahn-Teller distorted octahedral geometry, with coordination by the tridentate chelating ligand, an acetonitrile molecule, and two axial perchlorate anions. The tridentate ligand bis(2-pyridylmethyl)amine chelates meridionally and equatorially while an acetonitrile molecule is coordinated at the fourth equatorial site. The two perchlorate anions are disordered with site occupancy factors of 0.72/0.28. The amine H is involved in intramolecular hydrogen bonding to the perchlorate O atoms and there are extensive but weak intermolecular C-HÁ Á ÁO interactions.

S1. Comment
Bis(2-pyridylmethyl)amine (L 1 ) has been used as a chelating ligand for several metal ions, as a single unit, or as two or more units bridged by other groups (such as m-xylyl spaces or aliphatic hydrocarbon chains) through the amine N atom (Gultneh et al., 1999;Palaniandavar et al., 1995;Belle et al., 2002;Humphreys et al., 2002). We report here the structure of the copper (II) complex of the ligand L 1 . The complex was synthesized by the reaction of L 1 with Cu(ClO 4 ) 2 .6H 2 O in acetonitrile.
The crystal structure shows that Cu II is six-coordinate in a Jahn-Teller distorted geometry with coordination by the tridentate chelating ligand, an acetonitrile molecule, and two axial perchlorate anions ( Fig. 1.). The tridentate ligand L 1 is chelating meridionally and equatorially while an acetonitrile molecule is coordinated at the fourth equatorial site. One axial perchlorate group is at a Cu II -OClO 3distance of 2.455 (9) Å while the other is at 2.828 (5) Å consistent with its ( Table 1.).

S2. Experimental
The title compound, bis(2-pyridylmethyl)amine copper(II) acetonitrile bis(perchlorate), was obtained by refluxing bis(2pyridylmethyl)amine (2 mmol) and copper(II) perchlorate hexahydrate (2 mmol) in 200 ml of acetonitrile for 1 h. The product deposited on cooling the solution. Suitable crystals suited for crystallographic structure determination were obtained by slow diffusion of diethyl ether into the nitromethane solution of the complex.

S3. Refinement
The two perchlorate anions are disordered such that O11 and O21 are unique and the remaining O atoms are disordered over two conformations with occupancy factors of 0.708 (9), 0.292 (9)  The title compound with numbering scheme used. Ellipsoids are drawn at the 20% probability level.

Figure 2
The packing arrangement viewed down the c axis showing the intramolecular N-H···O and intermolecular C-H···O interactions in dashed lines. where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max = 0.001 Δρ max = 0.49 e Å −3 Δρ min = −0.46 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.