cyclo-Tetra-kis(μ-3-acetyl-4-methyl-1H-pyrazole-5-carboxyl-ato-κN,O:N,O)tetra-kis[aqua-copper(II)] tetra-deca-hydrate.

The title compound, [Cu(4)(C(7)H(6)N(2)O(3))(4)(H(2)O)(4)]·14H(2)O, a tetra-nuclear [2†×†2] grid-type complex with S4 symmetry, contains four Cu(II) atoms which are bridged by four pyrazole-carboxyl-ate ligand anions and are additionally bonded to a water molecule. Each Cu(II) atom is coordinated by two O atoms of the carboxyl-ate and acetyl groups, two pyrazole N atoms of doubly deprotonated 3-acetyl-4-methyl-1H-pyrazole-5-carb-oxy-lic acid and one O atom of a water mol-ecule. The geometry at each Cu(II) atom is distorted square-pyramidal, with the two N and two O atoms in the equatorial plane and O atoms in the axial positions. O-H⋯O hydrogen-bonding interactions additionally stabilize the structure. One of the uncoordinated water molecules shows half-occupancy.