The double-stranded ladder-like structure of poly[[bis(μ2-acetato-κ(2)O:O')bis(acetato-κO)bis(μ-4,4'-bipyridine-κ(2)N:N')dicopper(II)] 4-nitrophenol disolvate tetrahydrate].

The reaction of 4,4'-bipyridine with copper acetate in the presence of 4-nitrophenol led to the formation of the title compound, {[Cu(CH3COO)2(C10H8N2)]·C6H5NO3·2H2O}n. The complex forms a double-stranded ladder-like coordination polymer extending along the b axis. The double-stranded polymers are separated by 4-nitrophenol and water solvent molecules. The two Cu(II) centres of the centrosymmetric Cu2O2 ladder rungs have square-pyramidal coordination environments, which are formed by two acetate O atoms and two 4,4'-bipyridine N atoms in the basal plane and another acetate O atom at the apex. The ladder-like double strands are separated from each other by one unit-cell length along the c axis, and are connected by the water and 4-nitrophenol molecules through a series of O-H···O and C-H···O hydrogen-bonding interactions and two unique intermolecular π-π interactions.