摘要
在溶剂热条件下,由2-(4′-羧基苯基)咪唑-4,5-二羧酸(H_4L,C_(12)H_8N_2O_6),合成了4个配位聚合物{[M(H_3L)_2]·2H_2O}_n(M=Zn(1),Cd(2),Co(3)),[Cd(H_2L)(H_2O)]_n(4)。用元素分析、红外光谱、热重分析和单晶X射线衍射对配合物进行了表征和结构分析。结构分析结果表明:1～3是异质同晶。配体失去1个质子以H_3L^-的形式通过单齿和N,O-双齿螯合的配位模式与中心金属离子配位,构成一个略有变形的八面体结构。对于配合物4来说,配体失去2个质子以H_2L^(2-)的形式分别通过单齿和N,O-双齿螯合的配位方式与Cd^(2+)配位,中心离子采取扭曲的七配位五角双锥配位模式,并且通过配体苯环上羧基氧原子的双齿桥联作用连接2个中心离子,形成四元环的双核结构;同时呈现双节点(3,6)-连接的二维拓扑网络(4.4.4)(4.4.4.4.4.4.5.6.6.6.6.6)。测定了产物的固体荧光光谱;用EtBr荧光探针法研究了配体及配合物与ct-DNA的相互作用。
Four transition metal coordination polymers of two series,{[M(H3L)2]·2H2O}n (M=Zn (1), Cd (2), Co (3)) and [Cd(H2L)(H2O)]n (4), have been synthesized by solvothermal reaction from 2-(4′-carboxyphenyl)-1H-imidazole-4,5-dicarboxylic acid (H4L, C12H8N2O6) and characterized by IR, EA, TG. Single crystal X-ray diffraction shows that 1~3 are heterogeneous. Every ligand loses one proton in the form of H3L^-, and coordinates with the central metal ion by the coordination mode of monodentate and N, O-double-dentate chelate to form a slightly deformed octahedral structure. In complex 4, every ligand loses two protons in the form of H2L^2-, which coordinates with the central metal ion by the coordination mode of monodentate and N,O-double-dentate chelation. The central ion adopts a twisted seven-coordinate pentagonal double-cone coordination mode, and the two central ions are connected by the double-tooth bridging of the carboxyl oxygen atom on the ligand benzene ring to form a dinuclear structure of a four-membered ring, meanwhile they exhibit 2D structures with two-node (3,6)-connected frameworks with (4.4.4)(4.4.4.4.4.4.5.6.6.6.6.6) topology. The fluorescence spectra in the solid state and DNA binding properties of the polymers and ligand were investigated. CCDC: 1882051, 1;1882049, 2;1882052, 3;1882080, 4.
作者
鲁雅
管全银
张敏芝
赵国良
LU Ya;GUAN Quan-Yin;ZHANG Min-Zhi;ZHAO Guo-Liang(Xingzhi College, Zhejiang Normal University, Jinhua, Zhejiang 321004, China;College of Chemistry and Life Science, Zhejiang Normal University, Jinhua, Zhejiang 321004, China)
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2019年第5期855-864,共10页
Chinese Journal of Inorganic Chemistry
基金
浙江省自然科学基金(No.LY12B01003)资助项目
