We report five novel uranyl coordination polymers, [(CH)NH]UO(BTPCA) (1), [(CH)NH]UO(BTPCA) (2), [(CH)NH][UO(BTPCA)][UO(BTPCA)]·(HO) (3), [(CH)NH](UO)(BTPCA)·(HO) (4), and [(CH)NH]UO(BTPCA) (5), by the utilization of semirigid ligand 1,1',1″-(benzene-1,3,5-triyl)tripiperidine-4-carboxylic acid (HBTPCA) and uranyl nitrate through solvothermal reactions. Single-crystal X-ray diffraction analysis reveals that the five compounds share a similar structure composition and local coordination mode to the exclusion of disordered water or DMF molecules. Each UO(COO) motif is connected to six neighboring units through three BTPCA ligands, generating an infinite uranyl honeycomb (6, 3) net. The structures of all the five compounds consist of 2D honeycomb nets of various degrees of distortions, which are induced by the flexibility of piperidine rings. The dimethylamine cations and solvent molecules fill in the space between layers. Therefore, these five compounds are isomers in a broad sense. Notably, both compounds 3 and 4 possess 2-fold interpenetrated structures. For compound 5, the distance between the neighboring 2D honeycomb nets is 7.253 Å. This is the largest distance between the 2D honeycomb nets in uranyl-based coordination polymers, to the best of our knowledge. In addition, compounds 1, 2, and 4 are also characterized by infrared spectroscopy (IR), thermogravimetric analysis (TG), powder X-ray diffraction (PXRD), and luminescence properties.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.