[μ₃-cis-N-(2-Aminoethyl)-N′-(2-carboxylatophenyl)oxamidato(3−)]bis(2,2′-diamino-4,4′-bi-1,3-thiazole)tetracopper(II) bis(2,4,6-trinitrophenolate)

Abstract

The title complex, [Cu(4)(C(11)H(10)N(3)O(4))(2)(C(6)H(6)N(4)S(2))(2)](C(6)H(2)N(3)O(7))(2), consists of a circular tetracopper(II) cation with an embedded inversion centre and two uncoordinated picrate (2,4,6-trinitrophenolate) anions. The Cu(II) cations at the inner sites of N-(2-aminoethyl)-N'-(2-carboxylatophenyl)oxamidate(3-) (oxbe) have square-planar environments and those at the outer sites are in square-pyramidal geometries. The separations of pairs of Cu(II) cations bridged by cis-oxamide and carboxylate groups are 5.2217 (5) and 5.2871 (5) A, respectively. The tetracopper(II) cations and picrate anions are connected by N-H...O hydrogen bonds into a two-dimensional network parallel to the (010) plane, and these two-dimensional networks are assembled by two types of pi-pi stacking interactions into a three-dimensional supramolecular structure.