Resorcin[4]arene-Based Microporous Metal-Organic Framework as an Efficient Catalyst for CO2 Cycloaddition with Epoxides and Highly Selective Luminescent Sensing of Cr2O72.

A stable microporous anionic metal-organic framework (MOF), [(CH3)2NH2]6[Cd3L(H2O)2]·12H2O (1), has been synthesized via solvothermal assembly of a new resorcin[4]arene-functionalized dodecacarboxylic acid (H12L) and Cd(II) cations. The constructed MOF (1) was characterized by single-crystal X-ray diffraction and other physicochemical analyses. 1 exhibits a fascinating 3D microporous framework structure, in which the free water molecules and the [(CH3)2NH2]+ cations were located. Remarkably, the exposed Lewis acid Cd(II) sites of activated 1 make it an efficient heterogeneous catalyst for the cycloaddition of CO2 with epoxides at 1 and 20 atm. Importantly, the activated samples of 1 can be reused at least five circles with excellent catalytic performance. Moreover, the fluorescence detection of Cr2O72- and Fe3+ was studied by using 1 as a potential luminescent sensor.