HEPTACOORDINATE CU-II IN CATENA-POLY[AQUABIS(BENZIMIDAZOLE-N-3)COPPER(II)MU-ADIPATO-O,O'O'',O''']

The title compound, [Cu(C6H8O4)(C7H6N2)(2)(H2O)], has been synthesized and its crystal structure determined by single-crystal X-ray diffraction at room temperature. The seven-coordinate Cu-II complexes adopt a C-2 elongated tetragonal pyramidal geometry with double-capped base, The Cu atoms are located on the twofold axes and are connected by bridging tetradentate adipate ions to form polymeric chains. In the base of the coordination polyhedron, the two short Cu-N bonds are 2.007 (2) Angstrom in length and the two short Cu-O bonds are 2.010 (2) Angstrom. The length of the apical Cu-H2O bond is 2.245 (4) Angstrom; the lengths of the two long semicoordinate Cu-O bonds which complete the seven coordination, are 2.930 (2) Angstrom. The intermolecular hydrogen bonds and geometry of the carboxylate group are discussed.