Hydrothermal synthesis of a 1D paddle-wheel Cu(II) coordination polymer {[Cu2(NBDOA)2•(H2O)2]•2(H2O)}n constructed by flexible carboxylic acid

A 1-D paddle-wheel copper (II) coordination polymer constructed by 2-nitrobenzene-1,4-di(oxyacetic) acid has been synthesized by hydrothermal reaction, and its crystal structure was determined by X-ray diffraction. The crystal is of triclinic, space group P1 with a = 7.7257(12), b = 8.3648(13), c = 11.5516(18) angstrom, alpha = 76.654(2), beta = 82.088(2), gamma = 63.636(2)degrees, C20H22Cu2N2O20, M-r = 737.48, V = 650.27(18) angstrom(3), D-c = 1.883 g/cm(3), F(000) = 374, mu = 1.737 cm(-1) and Z = 1. The final refinement gave R = 0.0345 and wR = 0.0995 for 1996 observed reflections with I > 2 sigma(I). The coordination polymer demonstrates a 1-D microporous structure, and the channel is formed by two NBDOA(2-) and two Cu2+ ions. The ligand NBDOAH(2) displays a good flexible characteristic. The 1-D chains are connected to a 3-D supramolecular network by hydrogen bonds.