μ-Oxalato-κ⁴O¹,O²:O^1′,O^2′-bis­[aqua­(2,2′-bipyridyl-κ²N,N′)copper(II)] bis­(hydrogen squarate)

The title compound, [Cu₂(C₂O₄)(C₁₀H₈N₂)₂(H₂O)₂](C₄HO₄)₂, contains a dinuclear μ-oxalato–dicopper(II) complex cation in which the oxalate ligand (ox) bridges the Cu atoms in a bis-bidentate fashion. The square-pyramidal environment of each Cu atom is completed by the two N atoms of the 2,2′-bipyridine ligand (bpy) and by one apical water mol­ecule. The hydrogen squarate counter-anions (Hsq) form cyclic dimeric units through strong O—H...O hydrogen bonds. The crystal structure shows alternating hydrogen-bonded complex cations and cyclic anionic units.

(2,2′-Bipyridyl-κ²N,N′)(chloranilato-κ²O,O′)copper(II)

The Cu atom in the title complex, [Cu(C₆Cl₂O₄)(C₁₀H₈N₂)], has a square-planar CuN₂O₂ environment. The structure is built of monomeric neutral, essentially planar, mol­ecules stacked along the b axis, with the stacks held together by means of weak π–π, π...Cl, and π...Cu inter­actions. The mol­ecules of neighbouring stacks are linked via C—H...O hydrogen bonds.