镍(Ⅱ)/2,4,6-吡啶三酸配合物的合成和结构(英文)

采用水热方法合成了镍(Ⅱ)/2,4,6-吡啶三酸(H3L=2,4,6-pyridinetricarboxylic acid)的配合物(1);利用红外光谱和单晶X射线衍射表征了其晶体结构.配合物1属三斜晶系,P-1空间群,晶胞参数为:a=1.020 27(15)nm,b=1.112 93(17)nm,c=1.461 6(2)nm,α=75.026(3)°,β=78.291(2)°,γ=65.384(2)°,V=1.449 0(4)nm3,Z=2.配合物中的镍(Ⅱ)离子处于两种不同的配位环境.其中部分镍(Ⅱ)离子与配体中的两个羧基及氮原子配位,其余的镍(Ⅱ)离子与六个水分子配位;而配体吡啶环上的4-位羧基未与Ni(Ⅱ)离子配位.与此同时,配合物中形成复杂的氢键,通过氢键连接形成三维结构.

Synthesis and Structure of Ni(Ⅱ)Complex With Pyridine-2,4,6-tricarboxylic Acid

Ni(Ⅱ)complex with 2,4,6-pyridinetricarboxylic acid,Ni2.5(L)(HL)(H2O)9]·3.5H2O(1)H3L = 2,4,6-pyridinetricarboxylic acid), was synthesized by using hydrothermal method. The product was characterized by means of infrared spectrometry and single crystal X-ray diffraction. Results show that the complex crystallizes in triclinic crystal system and P-1 space group, with crystallographic data being a = 1.020 27(15)nm, b = 1.112 93(17)nm, c = 1.461 6(2)nm, α = 75.026(3)°, β = 78.291(2)°, γ = 65.384(2)°, V = 1.449 0(4)nm3 and Z = 2. Ni(Ⅱ)ions in the complex have two different coordination environments. Namely, some Ni(Ⅱ)ions coordinate with ligand H3L by way of two carboxyl groups and one nitrogen atom, the others coordinate with six water molecules. Besides, 4-carboxyl group of H3L does not coordinate with Ni(Ⅱ)ion, and complicated hydrogen bonds are formed in the crystal, resulting in three-dimensional structure.