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在水热条件下,合成了2个含柔性配体柠檬酸和酒石酸的二价铅配位聚合物[Pb6(H2O)2(cit)4].3H2O(1)(H3cit=citricacid)及Pb(tar)(H2O)2(2)(tar=tartaricacid).用红外光谱、差热-热重、元素分析、粉末X射线衍射及单晶X射线衍射等手段对化合物进行了表征.化合物1属三斜晶系,P1空间群,a=0.97053(19)nm,b=0.9764(2)nm,c=1.0955(2)nm,α=109.016(3)°,β=98.380(3)°,γ=92.136(3)°,V=0.9671(3)nm3,Z=2,R1=0.0420,wR2=0.1049,GOF=1.064.在化合物1的不对称结构单元中,有3个铅离子以及2个柠檬酸阴离子和2个游离的水分子.铅离子分别以4,5,7配位与柠檬酸配合形成了中性的三维骨架结构.化合物2属于正交晶系,Pbca空间群,a=1.39739(6)nm,b=0.64922(2)nm,c=1.80354(10)nm,V=1.63620(13)nm3,Z=8,R1=0.0283,wR2=0.0649,GOF=1.014.在化合物2的不对称结构单元中,有1个铅离子、1个酒石酸分子和1个水分子,六配位的铅和酒石酸形成了一维外消旋的无限长链,链与链之间通过氢键连接成一个三维超分子结构.在化合物1和2中,两种配体均出现了α羟基和α羧基螯合的配位模式,铅的6s孤电子对均显示了立体化学活性,使配位键分布于半球区域.
Under hydrothermal conditions, two dibasic lead coordination polymers [Pb6 (H2O) 2 (cit) 4] and3H2O (H3cit = citric acid) and Pb The compounds were characterized by FT-IR, TG-DTA, elemental analysis, powder X-ray diffraction and single crystal X-ray diffraction. Compound 1 belongs to tris (tartaric acid) A = 0.97053 (19) nm, b = 0.9764 (2) nm, c = 1.0955 (2) nm, α = 109.016 (3) °, β = 98.380 92.136 (3) °, V = 0.9671 (3) nm3, Z = 2, R1 = 0.0420, wR2 = 0.1049 and GOF = 1.064 In the unsymmetrical building block of compound 1, there are 3 lead ions and 2 citric acid Anions and two free water molecules.The lead ions coordinated with citric acid to form a three-dimensional framework with neutral structure.The compounds 2 belong to orthorhombic system, Pbca space group, a = 1.39739 (6 ), b = 0.64922 (2) nm, c = 1.80354 (10) nm, V = 1.63620 (13) nm3, Z = 8, R1 = 0.0283, wR2 = 0.0649, GOF = 1.014. In the asymmetric structure of compound 2 Unit, there is a lead ion, a tartaric acid molecule and a water molecule, hexacoordinated lead and tartaric acid to form a one-dimensional racemic infinite chain, chain and chain between Hydrogen bond to form a three-dimensional supramolecular structure.In compounds 1 and 2, both ligands showed the coordination mode of α-hydroxyl and α-carboxyl groups, and the 6s lone pairs of lead showed stereochemical activity Coordination keys distributed in the hemisphere area.