4,4′-Bipyridinium bis(oxalato-κ2O1,O2)cuprate(II): an ion-pair complex

Abstract

The title compound, (C10H10N2)[Cu(C2O4)2] or (4,4′-H2bpy)[Cu(ox)2] (bpy is 4,4′-bipyridine and ox is oxalate), is an ion-pair complex comprising a protonated 4,4′-bipyridinium dication and a square-planar dioxalatocopper(II) dianion. In the centrosymmetric dianion, the CuII centre is coordinated by four O atoms from the two dicrete oxalate ligands [Cu—O = 1.9245 (19) and 1.9252 (17) Å], while the planar dications are also centrosymmetric. Inter-species N—H...O hydrogen bonds link the cations and anions into one-dimensional chains and, together with weak intra-ion C—H...O interactions, give a two-dimensional sheet structure.