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A homochiral metal-organic framework, [Ni(D-L)(py)2(H2O)2]n (1) [D-H2L = 4,4′-[[(1R,3S)-1,2,2-trimethylcyclopentane-1,3-dicarbonyl]bis-(azanediyl)]dibenzoic acid], has been successfully synthesized based on D-camphorate-derived enantiopure ligand. 1 was characterized by single-crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), Fourier transform infrared spectral analysis (FTIR), thermogravimetric analysis (TGA) and the circular dichroism (CD) spectrum. The experimental results show that 1 features a homochiral triple helix and is formed a 3D supramolecular framework by supramolecular interactions. In addition, the circular dichroism (CD) spectrum verifies the chirality introduction from the ligand to crystal. The successful preparation of the homochiral Ni-MOF provides more possibilities of employing the chiral ligand to produce various chiral MOFs. [ABSTRACT FROM AUTHOR]

The development of a highly selective and sensitive optical method for quantitative enantioselective sensing of chiral amino acids in the presence of other amino acid interferences has remained a major challenge to date. Herein, a homochiral metal–organic framework (MOF), [Zn(L)(2,2′‐bipy)]·H2O (LNNU‐1) (H2L = HOOCC6H4CH2PO(OH)(OC2H5), 2,2′‐bipy = 2,2′‐bipyridine), is designed to interact with tryptophan via multiple noncovalent interactions. The interactions result in the emergence of a strong induced circular dichroism signal. This enables accurate determination of the absolute configuration and enantiomeric ratio of chiral tryptophan in water, mixed natural amino acids, and blood plasma components without any interference from other coexistent species. A simple device with advantageous characteristics of reusability and simple manipulation is designed for enantioselective sensing assay. The obtained results suggest that the rationally designed homochiral MOF is a promising candidate for enantioselective sensing of chiral species. [ABSTRACT FROM AUTHOR]