以廉价易得的3,5-二溴甲苯和1,3,5-三溴苯为初始原料,通过两步反应设计合成了二种含120°夹角的刚性羧酸桥联配体L1-H2(2a)和L2-H2(2b);并利用水热-溶剂热反应与镉离子合成了两种新颖的镉基配位聚合物[CdL1]·DMF·H2O(3a)和[CdL2]·DMF·H2O(3b),其结构经X-射线单晶衍射、X-射线粉末衍射和IR表征.3a和3b均属于正交晶系,Pbca空间群,中心金属镉离子采取扭曲的五角双锥配位构型,两个镉离子所形成的双核Cd2(OAc)2单元与周围的四个配体相互连接而成二维的网状结构.TGA显示配合物3a和3b的网络结构的热分解温度分别为355℃和360℃,具有较好的热稳定性.配体2a和2b的荧光光谱显示最大发射波长分别位于415和383 nm处,而3a和3b的最大发射波长分别位于362 nm和357 nm处,发生了明显蓝移.%Two rigid bridging ligands, L1-H2(2a) and L2-H2(2b), were synthesized using 1,3-dibro-mo-5-methylbenzene and 1,3,5-tribromobenzene as starting materials , respectively, which were em-ployed to prepare two Cd-based coordination polymers, [CdL1]· DMF· H2O(3a) and [CdL2]· DMF· H2O(3b).The structures were characterized by IR, TGA, single and powder X-ray diffrac-tion.3a is isostructural with 3b, and they crystallize in the orthorhombic space group Pbca.The Cd ( II) centers adopt a distorted pentagonal bipyramid geometry .The dinuclear Cd 2 ( OAc ) 2 units con-structed by two Cd ( II) ions are linked by four ligands to generate a two dimensional network .Thermo-gravimetric analysis showed that 3a and 3b are thermally robust with network decomposition tempera-ture up to 355 ℃ and 360 ℃, respectively.The fluorescence spectra of 2a and 2b in solid state at room temperature showed their major emission peaks located at approximately 415 and 383 nm, respec-tively.Compared with the two free ligands , the fluorescence spectra of 3a and 3b showed a marked blue shift, with their major emission peaks centered at 362 nm and 357 nm, respectively .
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