Di­aqua­bis(4,4′-bi­pyridine-N)­bis­(di­hydrogenphosphato-O)copper(II): blocking of extended metal–ligand coordination by hydrogen bonding

The title compound, Cu(H₂PO₄)₂(C₁₀H₈N₂)₂(H₂O)₂], is a mononuclear complex in which the Cu atom is square-planar coordinated by two di­hydrogenphosphate anions and two monodentate 4,4′-bi­pyridine (4,4′-bipy) groups, and by two more distant aqua ligands to complete a distorted octahedral coordination. Metal–metal bridging by 4,4′-bipy is blocked by inter­molecular hydrogen bonding from the di­hydrogen­phosphate to the second N atom of 4,4′-bipy. The crystal packing is controlled both by additional hydrogen bonding between the aqua and phosphate ligands and by π-stacking. These hydrogen-bonding interactions create two-dimensional networks which are connected by the bi­pyridine ligands.