Bis[mu(3)-cis-N-(2-aminopropyl)-N'-(2-carboxylatophenyl)oxamidato(3-)]bis(2,2'-bipyridine)dichloridotetracopper(II) dihydrate.

The title complex, bis[mu(3)-cis-N-(2-aminopropyl)-N'-(2-carboxylatophenyl)oxamidato(3-)]-1:2:4kappa(7)N,N',N'',O:O',O'':O''';2:3:4kappa(7)O''':N,N',N'',O:O',O''-bis(2,2'-bipyridine)-2kappa(2)N,N';4kappa(2)N,N'-dichlorido-1kappaCl,3kappaCl-tetracopper(II) dihydrate, [Cu(4)(C(12)H(12)N(3)O(4))(2)Cl(2)(C(10)H(8)N(2))(2)].2H(2)O, consists of a neutral cyclic tetracopper(II) system having an embedded centre of inversion and two solvent water molecules. The coordination of each Cu(II) atom is square-pyramidal. The separations of Cu(II) atoms bridged by cis-N-(2-aminopropyl)-N'-(2-carboxylatophenyl)oxamidate(3-) and carboxyl groups are 5.2096 (4) and 5.1961 (5) A, respectively. A three-dimensional supramolecular structure involving hydrogen bonding and aromatic stacking is observed.