摘要
A new flexible double betaine L （L = 1,4-bis（pyridinio-4-carboxylato-N-methyl）benzene, C20H16N2O4） and its cadmium（Ⅱ） complex [Cd（H2O）aL（NO3）]NO3.H2O 1 were synthesized. Complex 1 was obtained by self-assembly reaction of [Cd（NO3）2]-4H2O and L in hot water,and its crystal structure was determined by single-crystal X-ray diffraction analysis. Crystallographic data for complex 1： C20H24CdN4O14.H2O, Mr = 674.85, monoclinic, space group P21/c, a =13.7854（3）, b = 14.2820（3）, c = 14.9188（4） ,A°, β = 116.418（1）°, V = 2630.5（1）A°^3, Z = 4, Dc= 1.704g/cm^3,/J（MoKα） = 0.911 mm^-1, F（000） = 1368, the final R = 0.0315 and wR = 0.0768 for 3637 observed reflections with I 〉 2σ（I）. In complex 1, L acts as a monodentate ligand to link a Cd（Ⅱ） ion in a novel coordination mode of double betaines. The mononuclear [Cd（H2O）aL（NO3）] units are connected through intermolecular hydrogen bonds and π-π stacking reactions to generate a 3D network.
A new flexible double betaine L （L = 1,4-bis（pyridinio-4-carboxylato-N-methyl）benzene, C20H16N2O4） and its cadmium（Ⅱ） complex [Cd（H2O）aL（NO3）]NO3.H2O 1 were synthesized. Complex 1 was obtained by self-assembly reaction of [Cd（NO3）2]-4H2O and L in hot water,and its crystal structure was determined by single-crystal X-ray diffraction analysis. Crystallographic data for complex 1： C20H24CdN4O14.H2O, Mr = 674.85, monoclinic, space group P21/c, a =13.7854（3）, b = 14.2820（3）, c = 14.9188（4） ,A°, β = 116.418（1）°, V = 2630.5（1）A°^3, Z = 4, Dc= 1.704g/cm^3,/J（MoKα） = 0.911 mm^-1, F（000） = 1368, the final R = 0.0315 and wR = 0.0768 for 3637 observed reflections with I 〉 2σ（I）. In complex 1, L acts as a monodentate ligand to link a Cd（Ⅱ） ion in a novel coordination mode of double betaines. The mononuclear [Cd（H2O）aL（NO3）] units are connected through intermolecular hydrogen bonds and π-π stacking reactions to generate a 3D network.
基金
This work was supported by the NSF for Distinguished Young Scientist of China (20425104) and the NSF of Fujian Province (2005I017, A0420002)
