Song Tian-Qun, Dong Jie, Yang An-Fei, Che Xue-Jing, Gao Hong-Ling, Cui Jian-Zhong, Zhao Bin
Department of Chemistry, National Demonstration Center for Experimental Chemistry & Chemical Engineering Education, National Virtual Simulation Experimental Teaching Center for Chemistry & Chemical Engineering Education , Tianjin University , Tianjin 300072 , P. R. China.
Department of Chemistry , Nankai University , Tianjin 300071 , P. R. China.
Inorg Chem. 2018 Mar 19;57(6):3144-3150. doi: 10.1021/acs.inorgchem.7b03142. Epub 2018 Feb 26.
Two isostructural 2D MOFs ([Ln(CDA)(HCOO)(μ-OH)(HO)] , abbreviated as 1-Gd and 2-Dy) were successfully synthesized under solvothermal conditions. The self-assembly of lanthanide(III) nitrate and 1,1'-cyclopropane-dicarboxylic acid (HCDA) resulted in wheel-like Ln cluster second building units (SBU), which are further linked to six neighboring wheels to generate a 2D ordered honeycomb array. Both 1-Gd and 2-Dy exhibit high thermal stability and decompose above 330 °C. Moreover, they have good solvent stability in ten common solvents and pH stability with pH values from 1 to 13. Magnetic studies reveal that 1-Gd exhibits weak antiferromagnetic coupling between adjacent Gd ions and has a large magnetocaloric effect of 47.30 J kg K (Δ H = 7.0 T at 2 K), while 2-Dy shows ferromagnetic interaction between adjacent Dy ions. Interestingly, 1-Gd and 2-Dy can catalyze the cycloaddition of CO to epoxides under mild conditions and can be reused at least five rounds with negligible loss of catalytic performance.
在溶剂热条件下成功合成了两种同构的二维金属有机框架化合物（[Ln(CDA)(HCOO)(μ-OH)(HO)]，简称为1-Gd和2-Dy）。硝酸镧(III)与1,1'-环丙烷二羧酸（HCDA）自组装形成轮状的Ln簇二级构筑单元（SBU），这些单元进一步与六个相邻的轮相连，形成二维有序蜂窝状阵列。1-Gd和2-Dy均表现出高热稳定性，在330℃以上分解。此外，它们在十种常见溶剂中具有良好的溶剂稳定性，在pH值为1至13的范围内具有pH稳定性。磁性研究表明，1-Gd在相邻Gd离子之间表现出弱反铁磁耦合，在2 K时具有47.30 J kg K的大磁热效应（ΔH = 7.0 T），而2-Dy在相邻Dy离子之间表现出铁磁相互作用。有趣的是，1-Gd和2-Dy可以在温和条件下催化CO与环氧化物的环加成反应，并且可以重复使用至少五轮，催化性能损失可忽略不计。
