摘要
在溶剂热条件下,将一个V-型双咪唑配体1.1’-(5-甲基-1,3-亚苯基)二(1H-咪唑)(Bim)与其它V-型辅助配体(具有不同的对称性和功能基团的芳香羧酸)一起与金属盐ZnSO4·6H2O进行反应,分别得到2个新的配位聚合物{[Zn(Bim)(Bra)2]·CH3OH}n(1)和{[Zn(Bim)(Mpa)]·H2O}n(2)(Bra-=5-溴烟酸根,Mpa2-=5-甲基间苯二甲酸根)。采用红外光谱、元素分析、X射线粉末衍射、X射线单晶衍射和热重分析对配合物进行了表征。配合物1是由配体Bim桥联形成的一维链状结构并进一步通过链间的π…π、C-H…π和Br…π作用堆积成一个三维超分子。在2中,Zn(Ⅱ)离子通过Mpa^2-桥联形成左手和右手螺旋链.这些具有不同手性的螺旋链进一步通过Bim联接形成具有(4,4)拓扑结构的内消旋的二维层。相邻的二维层之间的交错对插、层间配体分子Bim的咪唑环和苯环的双重π…π作用最终形成了三维超分子。固态荧光测试结果表明:在室温条件下,配体Bim和配合物1-2均出现了有趣的多重发射峰.而且在配合物1中四配位的Zn(Ⅱ)离子中心能显著地敏化配体Bim的高强度发射峰。
A V-shaped bis-imidazole ligand 1,1'-(5-methyl-1,3-phenylene)-bis(1H-imidazole) (Bim) in combination with auxiliary V-shaped ligands aromatic carboxylic acids of different symmetry and functional groups was selected to react with ZnSO4· 6H2O under solvothermal condition, and two new coordination polymers, {[Zn(Bim) (Bra)2]· CH3OH}n (1) and {[Zn (Sire) (Mpa)]· H2O}, (2), were obtained (Bra-=5-bromonicotinate and MpaZ-=5- methylisophthalate). The two compounds were characterized by IR spectra, element analysis, powder X-ray diffraction, single-crystal X-ray diffraction, and thermogravimetric analysis. Compound 1 features Bim-hridged one-dimensional chain structures which stack up through interchain π…π, C-H…π and Br…π interactions to form a three-dimensional supramolecule. In 2, zinc(Ⅱ) ions are bridged by Mpa2- ligands to form left- and righthanded helical chains which are further linked into (4,4) meso layers through Bim molecules. Finally, a 3D supramolecular framework forms through the interdigitation and double π…π interactions between the imidazole and phenyl of Bim molecules in adjacent layers. Solid state fluorescence measurements confirm that at room temperature both free ligand Bim and complexes 1-2 displays interesting multiple emissions, and the four- coordinated Zn(Ⅱ) center in 1 can notably sensitize the high-energy emission of Bim. CCDC: 1061914, 1; 1061915, 2.
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2016年第2期360-368,共9页
Chinese Journal of Inorganic Chemistry
基金
国家自然科学基金(No.21271157)
河南省基础与前沿技术研究计划项目(No.122300410092)
河南省科技攻关计划项目(No.122102210415)资助
关键词
配位聚合物
晶体结构
热稳定性
荧光
双咪唑配体
coordination polymers
crystal structure
thermal stability
fluorescence
bis-imidazole ligand