New 3-D supramolecular networks formed via hydrogen bonding and π-π stacking interactions:: Synthesis, characterization and crystal structures

Two new 3-D supramolecular networks, {[Cd-2(dap)(2)(tp)(2)(H2O)(2)]center dot 2H(2)O}(n) (1) and {[Cu-3(tp)(2)(dpq)(2)(OH)(2)]}, (2) (tp, terephthalate; dap, 5,6-diamino-1,10-phenanthroline; dpq, dipyrido[3,2-d:2',3'-f]quinoxaline), have been synthesized and structurally characterized by X-ray diffraction. Single-crystal X-ray analyses show that complex 1 is constructed by Cd-II and mixed ligands of daps and tps to form a 1-D polymer chain. In complex 2, a tetra-coordinated Cull and two penta-coordinated Cu-II are linked by two bridging hydroxyl oxygen atoms to form a Cu-3(OH)(2)(dpq)(2) unit, which is a noteworthy feature in the framework, and such units are connected through tp to form a 2-D lamellar polymer. Moreover, complexes 1 and 2 are further extended into 3-D supramolecular networks by H-bonding and pi-pi stacking interactions, respectively. (c) 2006 Elsevier B.V. All rights reserved.