A One-dimensional Cobalt Coordination Polymer Based on Biphenyl-2,3,3?,5?-tetracarboxylic Acid and N-donor Ancillary Ligands: Crystal Structure and Magnetic Property

李荣芳王玉芳刘新芳冯勋张晓宇杜德光

College of Chemistry and Chemical Engineering,Luoyang Normal University Food and Bioengineering Department, Henan University of Science and Technology Luoyang Huier Nano Science and Technology Co Ltd

摘要：Hydrothermal reactions of biphenyl-2,3,3?,5?-tetracarboxylic acid（H4bptc） with cobalt salt in the presence of 1,4-bis（2-pyridylmethyl）piperazin（bpmp） afforded one novel coordination polymer, namely, [Co（H2bptc）（bpmp）0.5（H2O）]n（1）. Its structure was established by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectra and TG analysis. Complex 1 crystallizes in monoclinic, space group P21/c with a = 11.4839（11）, b = 16.6690（16）, c = 11.5559（11） ?, V = 2201.8（4） ?3, Mr = 539.35, Dc = 1.627 g/cm3, μ（MoK α） = 0.841 mm-1, F（000） = 1108, Z = 4, the final R = 0.0309 and w R = 0.0705 for 4090 observed reflections（I ＞ 2σ（I））. Complex 1 displays a one-dimensional（1D） chain bridged by bpmp. Two carboxylic groups of H4 bptc ligand adopt μ01-η1:η1 and μ1-η1:η coordination modes to bridge adjacent Co（Ⅱ） ions together with bpmp ligand to give alternately arranged left- and right-handed helical chains. In addition, variable-temperature magnetic susceptibility measurements indicate that complex 1 shows weak antiferromagnetic interactions between the adjacent Co（Ⅱ） ions.

基金资助：

supported by the National Natural Science Foundation of China（No.21273101 and 21302082）； the Foundation of the Program for Backbone Teachers in Universities of Henan Province（No.2012GGJS158）；