catena-Poly[[(2-phenyl-1H-1,3,7,8-tetraazacyclopenta[l]phenanthrene-kappa2N7,N8)cadmium(II)]-di-mu-chlorido-[(2-phenyl-1H-1,3,7,8-tetraazacyclopenta[l]phenanthrene-kappa2N7,N8)cadmium(II)]-mu-fumarato-kappa4O1,O1':O4,O4']: a coordination polymer with a two-dimensional supramolecular architecture.

The title cadmium(II) coordination polymer, [Cd(2)(C(4)H(2)O(4))Cl(2)(C(19)H(12)N(4))(2)](n), (I), was obtained by the reaction of CdCl(2) x 2.5 H(2)O, fumaric acid (H(2)fum) and 2-phenyl-1H-1,3,7,8-tetraazacyclopenta[l]phenanthrene (L) under hydrothermal conditions. The fum dianion is situated across an inversion centre in the space group P1. The Cd(II) atom is six-coordinated by two L N atoms, two fum O atoms and two Cl atoms in a distorted octahedral geometry. The mu(2)-Cl atoms and the bis-chelating fum dianions bridge neighbouring Cd(II) centres, yielding a coordination polymer chain structure along the c axis. N-H...O hydrogen bonds between the N atoms of L and the carboxylate O atoms of fum lead to a sheet structure in the bc plane. Compound (I) represents a rare example of a supramolecular structure constructed by a chloride anion, a dicarboxylate anion and a 1,10-phenanthroline derivative. This work may further the development of the coordination chemistry of 1,10-phenanthroline derivatives.