Homochiral Tetraphenylethene-Based Metal–Organic Frameworks with Circularly Polarized Luminescence for Enantioselective Recognition

A pair of water-stable and highly porous homochiral fluorescent silver–organic framework enantiomers, namely, R-Ag-BPA-TPyPE (R-1) and S-Ag-BPA-TPyPE (S-1), had been prepared as enantioselective fluorescence sensors. Combining homochiral 1,1′-binaphthyl-2,2′-diyl hydrogen phosphate (BPA) with an AIE-based ligand tetrakis[4-(pyridin-4-yl)phenyl]ethene (TPyPE) in complexes R-1 and S-1 made them possess favorable circularly polarized luminescence (CPL) properties, and their CPL spectra were almost mirror images of each other. The luminescence dissymmetry factors (glum) are ±2.2 × 10–3 for R-1 and S-1, and the absolute fluorescence quantum yields (ΦFs) are 32.0% for R-1 and S-1, respectively. Complex R-1 could enantioselectively recognize two enantiomers of amino acids in water or DMF with high Stern–Volmer constants of 236–573 M–1 and enantioselectivity ratios of 1.40–1.78.