Hydrogen bonding in the crystal structure of bis[3-([thiomethyl]methyl)pyrazole]copper(II) perchlorate

The ability of a metal-coordinated pyrazole to engage in hydrogen bonding has been explored by synthesis of the title complex, bis3-(thiomethyl]methyl)pyrazole]copper(II) perchlorate (3). The coordination in 3 can be described as pseudo-octahedral, with two relatively tightly-bound 3-(thiomethyl)methyl]pyrazole ligands occupying the equatorial plane, forming a CuN(2)S(2)](2+) unit with the S donors mutually trans to each other. The axial positions are each filled by a weakly bound perchlorate counterion, one oxygen of which forms a hydrogen bond with the pyrazole N-H moiety on an adjacent CuN(2)S(2)](2+) unit.