具有新颖金属咪唑构筑单元的金属有机框架材料合成与性能  

Synthesis and properties of metal organic frameworks with novel metal-imidazolate secondary building units

作　　者：唐玉环 王飞[1] 张健[1] Yuhuan Tang;Fei Wang;Jian Zhang(State Key Laboratory of Structural Chemistry,Fujian Institute of Research on the Structure of Matter,Chinese Academy of Sciences,Fuzhou 350002,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院福建物质结构研究所结构化学国家重点实验室,福州350002 [2]中国科学院大学,北京100049

出　　处：《科学通报》2018年第22期2264-2271,共8页Chinese Science Bulletin

基　　金：国家自然科学基金(21425102;21573236)资助

摘　　要：利用咪唑衍生物2-(1-羟基-乙基)-3氢-苯并咪唑-5-羧酸(Hebimc)和金属锌盐反应得到一种新颖的次级构筑单元Zn_2(ebimc)_2.在此基础上,通过加入辅助配体和条件优化,成功合成了4例结构新颖的金属有机框架(MOFs)材料,其分子式分别为:Zn_2(Hebimc)4(1),Zn_2(Hebimc)2(BDC)?x G(2,BDC=对苯二甲酸,G=客体分子),Zn_2(Hebimc)_2(NDC)?xG(3,NDC=2,6-萘二酸),Zn_8(ebimc)_6(DOBDC)(OH)_2(H_2O)_2?x G(4,DOBDC=2,5-二羟基对苯二甲酸).其中,化合物1由Zn2(Hebimc)2单元自身首尾相连形成一维链结构;在化合物2和3中,通过加入辅助羧酸配体BDC或NDC,Zn_2(Hebimc)_2单元被辅助配体连接形成二维层状结构;在化合物4中,有机碱的加入使得Hebimc配体上的羧基和咪唑基同时脱去质子,表现出高的配位能力,Zn_2(Hebimc)_2单元和单核Zn相互连接形成层状结构,再通过DOBDC配体链接形成柱层式的三维框架.有意思的是,利用化合物4中的羟基官能团-OH和孔道限域效应,可以还原Ag^+离子形成均匀分散的纳米粒子,得到的复合材料Ag~@4对结晶紫水溶液有较好的光催化降解效果.本文对于金属有机框架材料的结构调控提供了新思路.Metal-organic frameworks（MOFs） are a class of inorganic-organic hybrid materials and have potential applications in many fields such as gas adsorption and storage,catalysis,ion exchange and separation,chemical sensing and so on.It has attracted a great deal of chemists＇ attention.Moreover,the development of new secondary building units（SBUs） is of great importance for the synthesis of MOFs.In this work,we choose 2-（1-hydroxy-ethyl）-3 H-benzo-imidazole-5-carboxylic acid（Hebimc） as organic ligand,which is a trifunctional imidazolate derivative comprising metal coordination groups and diverse functional sites.In this ligand,the imidazolate unit can provide μ2-bridging coordination mode to form zeolitic MOFs,the hydroxy unit could offer active site for further reactions,the benzene ring may offer π-π interaction with guest molecules for fascinating structures,and the carboxy unit also could coordinate to metal center.So far,MOFs assembled by Hebimc ligand and auxiliary dicarboxylic ligands have not been reported yet.By employing the Hebimc ligand and introduce auxiliary dicarboxylic ligands to assemble with different transition metal salts,respectively,four MOFs from one-dimensional（1 D） to three-dimensional（3 D）,namely,Zn_2（Hebimc）_4（1）,Zn_2（Hebimc）_2（BDC）？xG（2,BDC=terephthalic acid,G=guest molecule）,Zn_2（Hebimc）_2（NDC）？xG（3,NDC=2,6-naphthalene diacid）,Zn_8（Hebimc）_6（DOBDC）（OH）_2（H_2O）_2？x G（4,DOBDC=2,5-dih-ydroxyterephthalic acid）,have been synthesized under different reaction conditions.1 was synthesized by the reaction of Hebimc and Zn SiF_6·6H_2O in H_2O at 100°C for 3 d（yield：40% based on Hebimc）;2 was prepared by the reaction of Hebimc and BDC and Zn Si F6·6 H_2O in isopropanol/water（6：3,v：v） at 100°C for 3 d（yield：65% based on Hebimc）;3 was prepared by the reaction of Hebimc,NDC,pyrazine,tetraethylammonium bromide（TEAB） and Zn（NO_3）_2·6 H_2O in N,N-dimethyl formamide（DMF）/water（3：1.5

关 键 词：金属-有机框架材料 晶体工程 可控合成 单晶结构 染料降解 

分 类 号：O641.4[理学—物理化学]