Poly[[bis(μ-4,4′-bipyridine-κ2 N:N′)copper(I)] perchlorate 0.24-hydrate]

The title copper(I) polymeric compound, {[Cu(C10H8N2)2]ClO4·0.24H2O}n, obtained by the reaction of Cu(ClO4)2 and 4,4′-bipyridine (4,4′-bpy) under hydrothermal conditions, features a fourfold-interpenetrated diamondoid coordination framework. The asymmetric unit consists of two CuI atoms, three 4,4′-bpy ligands in general positions and two halves of two centrosymmetric 4,4′-bpy ligands, two ClO4 − anions and water molecule with a site-occupancy factor of 0.480 (17). The CuI atoms are in a distorted tetrahedral coordination environment and are bridged by 4,4′-bpy ligands, forming a diamondoid cationic polymeric framework that encloses two symmetry-independent channels along [100], which accommodate perchlorate anions and water molecules.

metal ions into open frameworks with channels (Yaghi & Li, 1996;MacGillivray et al., 1994;Xie et al., 2010). On the other hand, it has been found that under hydrothermal conditions used for preparation of MOFs many interesting phenomena including ligand oxidative coupling, hydrolysis, substitution and redox processes can occur (Liu et al., 2001;Xie et al., 2008). Encouraged by several recent reports on reduction of Cu II to Cu I under basic hydrothermal conditions (Yang et al., 2010;Xie et al., 2006), we designed and synthesized the title three-dimensional copper(I) coordination polymer and determined its crystal structure.

Experimental
A mixture of Cu(ClO 4 ) 2 . 6H 2 O (0.186 g, 0.5 mmol), 4,4′-bipy (0.192 g, 1 mmol) and H 2 O (18.0 ml) in the molar ratio of 1:2:1000 was sealed in a 25 mL stainless steel reactor with Teflon liner, and heated directly to 180°C. After keeping at 180°C for 72 h it was cooled slowly to 30°C at a rate of 2°C/h. The resulting orange block crystals were washed and dried in air (yield: 15%.).

Refinement
The H atoms of the aromatic rings were placed at calculated positions, with C-H = 0.93 Å and assigned U iso (H) = 1.2Ueq(C). A high peak in a difference Fourier map was interpreted as a water molecule with partial occupancy. The occupancy factor of water molecule refined at 0.480 (17). Hydrogen atoms of water molecule could not be located. O1W was refined with isotropic displacement parameter.

Data collection
Rigaku R-AXIS RAPID IP area-detector diffractometer Radiation source: fine-focus sealed tube Graphite monochromator ω scans Absorption correction: multi-scan (ABSCOR; Higashi, 1995) T min = 0.732, T max = 0.877 29543 measured reflections 6849 independent reflections 4507 reflections with I > 2σ(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 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq Occ.