Unprecedented cadmium(II) complex with (44.66) net topology and in situ ligand synthesis

Hydrothermal reactions of 4,4'-bipyridine-2,2'-dicarboxylic acid (H(2)BPDCA) with Cu(II) and Cd(II) nitrate salts result in the formation of two complexes [Cu(2,4-Hpydca)(2)(H2O)(2)] (1) and [Cd(2,4-pydca)](n) (2) with pyridine-2,4-dicarboxylate (2,4-pydca(2-)), rather than BPDCA(2-), as ligand, namely the in situ transformation of H(2)BPDCA to H(2)pydca occurred under the hydrothermal conditions. Complex 1 has been previously reported from different synthetic route, however, complex 2 is the first binodal 5-connecting 3D frame-work with unprecedented (4(4) . 6(6)) net topology. The results provide a new strategy for in situ ligand synthesis and construction of coordination polymers with specific topology. (C) 2008 Elsevier B.V. All rights reserved.