Catena-Poly[[bis-(μ-5-bromo-pyridine-3-carboxyl-ato-κ² O:O′)dicopper(II)]-bis-(μ-5-bromo-pyridine-3-carboxyl-ato) -κ³ O,O′:N;κ³ N:O,O′]

The title compound [Cu₂(C₆H₃BrNO ₂)₄]_n, forms sheets in the bc plane. The structure features the dinuclear paddle-wheel cage motif common to copper(II) carboxyl-ates. The polymeric structure is achieved through bridging between binuclear units by the pyridyl donors of two of the four carboxyl-ates of the cage. Each cage engages in axial bonding at each copper atom to a pyridyl nitro-gen donor and extends two 5-bromo-pyridine-3-carboxyl-ate groups to bridge to adjacent binuclear sites in the bc plane. Each cage is linked to four adjacent cages in the plane. The intra-dimer Cu⋯Cu distance is 2.6465 (5) Å. The remaining 5-bromo-pyridine-3-carboxyl-ate groups project into the inter-lamellar domain and inter-digitate in pairs from each neighboring layer.