catena-Poly[[bromidocopper(I)]-μ-η2,σ1-3-(2-allyl-2H-tetrazol-5-yl)pyridine]

The title compound, [CuBr(C9H9N5)]n, has been prepared by the solvothermal treatment of CuBr with 3-(2-allyl-2H-tetrazol-5-yl)pyridine. It is a new homometallic CuI olefin coordination polymer in which the CuI atoms are linked by the 3-(2-allyl-2H-tetrazol-5-yl)pyridine ligands and bonded to one terminal Br atom each. The organic ligand acts as a bidentate ligand connecting two neighboring Cu centers through the N atom of the pyridine ring and the double bond of the allyl group. A three-dimensional structure is formed through weak Cu—Br [3.1579 (8) Å], C—H⋯Br and C—H⋯N interactions.

The title compound, [CuBr(C 9 H 9 N 5 )] n , has been prepared by the solvothermal treatment of CuBr with 3-(2-allyl-2H-tetrazol-5-yl)pyridine. It is a new homometallic Cu I olefin coordination polymer in which the Cu I atoms are linked by the 3-(2allyl-2H-tetrazol-5-yl)pyridine ligands and bonded to one terminal Br atom each. The organic ligand acts as a bidentate ligand connecting two neighboring Cu centers through the N atom of the pyridine ring and the double bond of the allyl group. A three-dimensional structure is formed through weak Cu-Br [3.1579 (8) Å ], C-HÁ Á ÁBr and C-HÁ Á ÁN interactions.

Related literature
For the solvothermal synthesis and related structures, see: Ye et al. (2005Ye et al. ( , 2007.
The copper(I) is coordinated to two olefinic ligands and one terminal Br atom in a trigonal environment (Fig 1). The olefin ligands link the neighbouring Cu centers to form an homometallic Cu I coordination polymer developping along the c axis. The 3-(2-allyl-2H-tetrazol-5-yl) pyridine ligands coordinate to copper (I) centers through N atom of pyridine ring and double bond of allyl group. Unfortunately, the N atoms of tetrazole ring fail to coordinate to Cu(I).

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