Syntheses, crystal structures, and properties of four two-dimensional network complexes with multidentate bis(Schiff base) ligands

Four novel two-dimensional coordination polymers [Ag-2(L1)(2)](CF3SO3)(2)(H2O)-H-. (1), [Ag-3(L1)(2)](NO3)(3)(H2O)-H-. (2), [Co(L1)(2)(SCN)(2)](EtOH)-Et-. (3), and [Co(L2)(2)(SCN)(2)] (4) were obtained by reactions of the bis(Schiff base) ligand 1,2-bis(4'-pyridylmethyleneamino) ethane (L1) with silver(i) trifluoromethanesulfonate, silver(i) nitrate, and cobalt(ii) thiocyanate, and 1, 2-bis (3'-pyridylmethyleneamino) ethane (L2) with cobalt(ii) thiocyanate, respectively. In complex 1, a 2D network structure was achieved by hydrogen bonding interactions between the two 1D chains, consisting of double-stranded helicates, through solvate water molecules. The 2D network of complex 2 was formed by the coordination to a two-coordinate silver(i) ion instead of hydrogen bonds as in complex 1. Complex 3 contains molecular square units, which are occupied by disordered ethanol molecules. Complex 4 exhibits a classic square-grid network which is different from that of 3 due to the different terminal pyridyl groups in Ll (4-pyridyl) and L2 (3-pyridyl). These coordination polymers were characterized by X-ray crystallography, electrospray mass spectrometry, cyclic voltammetry and magnetic measurements. The results show a 2D network superstructural diversity by the fine-tuning of construction components. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003).