New coordination polymers with acylhydrazidate molecules as the linkers

Abstract

By employing the hydrothermal in situ acylation of N2H4 with aromatic polycarboxylic acids, three new acylhydrazidate-extended coordination polymers (CPs) [Pb2(3-cppth)2(phen)2] (3-cppth=4-(3-carboxyphenoxy)phthalhydrazidate, phen=1,10-phenanthroline) 1, [Cd(4-cppth)(bpy)(H2O)]·H2O (4-cppth=4-(4-carboxyphenoxy)phthalhydrazidate, bpy=2,2′-bipyridine) 2 and [Zn(dcpth)2] (dcpth=4,5-dichlorophthalhydrazidate) 3 were obtained. X-ray single-crystal diffraction analysis revealed that (i) compound 1 possesses a one-dimensional (1-D) double-chain structure. Via the N–H⋯O interactions between the neighboring acylamino groups, two such double chains aggregate together into a 1-D supramolecular chain. The phen molecules are distributed on the outer side of the supramolecular chain, hindering the further extension of the 1-D supramolecular chain; (ii) compound 2 exhibits a 1-D zigzag-type single-chain structure. Via the hydrogen-bonded interactions between the acylamino groups, compound 2 self-assembles into a two-dimensional (2-D) grid-like supramolecular layer network. The π⋯π interactions between the bpy molecules are observed between the supramolecular layers; (iii) in compound 3, two hydroxylimino groups for the dcpth I molecules link first the Zn2+ ions into a dimer, which can be viewed as a tetrahedral node. The dcpth II molecules act as the linkers, extending the tetrahedral nodes into another 1-D double-chain structure, different from that of compound 1.