A New Route for Preparing Coordination Polymers from Hydrothermal Reactions Involving in Situ Ligand Synthesis

The coordination chemistry of inorganic cobalt salt and the organic ligands H4bbh (=benzene-1,2,4,5-bihydrazide)
and H3bcbh (=benzene-4-carboxylate-1,2-bihydrazide) generated through the in situ hydrothermal acylate reaction
of H4bta (=benzene-1,2,4,5-tetracarboxylic acid) and H3btc (=benzene-1,2,4-tricarboxylic acid) with hydrazine hydrate,
respectively, has been investigated. Three new coordination polymers were prepared and fully characterized by
infrared spectroscopy, elemental analysis, and single-crystal X-ray diffraction. The compound [Co(μ3-H2bbh)(phen)]n
(1) (triclinic space group P1̄ with a = 9.762(4) Å, b = 10.169(4) Å, c = 11.143(4) Å, α = 80.96(3)°, β =
64.49(3)°, γ = 71.88(3)°, Z = 2) was synthesized from the reaction of CoCl2·6H2O, H4bta (=benzene-1,2,4,5-tetracarboxylic acid), N2H4·H2O, phen (=1,10-phenanthroline) and H2O, and consists of one-dimensional double-chains. [Co(μ4-H2bbh)(H2O)2]n (2) (monoclinic space group P2(1)/c with a = 6.8687(5) Å, b = 7.5943(6) Å, c =
10.0401(6) Å, β = 95.250(4)°, Z = 2) was generated by the combination of CoCl2·6H2O, H4bta, N2H4·H2O, and
H2O. It adopts a three-dimensional structural motif in the solid state with channels consisting of 20-numbered rings.
[Co(μ3-Hbcbh)(bpy)]n (3) (monoclinic space group Cc with a = 9.9464(13) Å, b = 23.685(5) Å, c = 7.9491 (16)
Å, β = 117.677(13)°, Z = 4) was obtained from the mixture of CoCl2·6H2O, N2H4·H2O, H3btc (=benzene-1,2,4-tricarboxylic acid), bpy (=2,2‘-dipyridyl), and H2O, and features a two-dimensional plane. The results of magnetic
research indicate that there exist antiferromagnetic interactions between Co centers in both compounds 1 and 2.

本研究针对无机钴盐与有机配体H4bbh（苯-1,2,4,5-双酰肼，benzene-1,2,4,5-bihydrazide）、H3bcbh（苯-4-甲酸酯-1,2-双酰肼，benzene-4-carboxylate-1,2-bihydrazide）的配位化学展开探究，其中上述两种有机配体分别由H4bta（苯-1,2,4,5-四甲酸，benzene-1,2,4,5-tetracarboxylic acid）、H3btc（苯-1,2,4-三甲酸，benzene-1,2,4-tricarboxylic acid）与水合肼通过原位水热酰化反应生成。我们成功合成了三种新型配位聚合物，并通过红外光谱、元素分析及单晶X射线衍射对其进行了全面表征。配合物[Co(μ3-H2bbh)(phen)]n（1）属于三斜晶系，空间群为P1̄，晶胞参数为a=9.762(4) Å，b=10.169(4) Å，c=11.143(4) Å，α=80.96(3)°，β=64.49(3)°，γ=71.88(3)°，Z=2，该配合物以CoCl2·6H2O、H4bta、水合肼、phen（1,10-邻菲啰啉，1,10-phenanthroline）与水为原料合成，结构为一维双链。配合物[Co(μ4-H2bbh)(H2O)2]n（2）属于单斜晶系，空间群为P2(1)/c，晶胞参数为a=6.8687(5) Å，b=7.5943(6) Å，c=10.0401(6) Å，β=95.250(4)°，Z=2，该配合物由CoCl2·6H2O、H4bta、水合肼与水反应制得，固态下呈现三维骨架结构，含有由20元环构成的孔道。配合物[Co(μ3-Hbcbh)(bpy)]n（3）属于单斜晶系，空间群为Cc，晶胞参数为a=9.9464(13) Å，b=23.685(5) Å，c=7.9491(16) Å，β=117.677(13)°，Z=4，该配合物以CoCl2·6H2O、水合肼、H3btc、bpy（2,2’-联吡啶，2,2‘-dipyridyl）与水为原料制备，结构为二维平面。磁学研究结果表明，配合物1和2中的钴中心之间均存在反铁磁相互作用。