Luminescent Metal–Organic Frameworks with Anthracene Chromophores: Small-Molecule Sensing and Highly Selective Sensing for Nitro Explosives

Five new luminescent metal–organic frameworks (MOFs), [Cd­(bdc)­(dia)0.5(MeOH)]­(DMA)0.5 (1), [Cd2O­(1,4-ndc)2(dia)2(H2O)]·DMA (2), [Cd­(1,4-ndc)­(dia)]·MeOH (3), [Cd­(bpdc)­(dia)0.5]·DMF (4), [Cd­(bpdc) (dia)]·DEF (5) (dia = 9,10-bis­(1H-imidazol-1-yl)­anthracene), were obtained from solvothermal conditions and characterized by PXRD, IR, TG, and PL spectra. Single-crystal X-ray diffraction analyses showed that all compounds 1–5 display three-dimensional architectures with diverse topologies. Compound 1 was a 6-con pcu network based on dinuclear Cd cluster. Compound 2 features an eight-connected network constructed from a binuclear Cd cluster. Compound 3 presents a 3-fold interpenetrated four-connected dia topology. Compounds 4 and 5 exhibit a 3-fold interpenetrated six-connected pcu framework and a 3-fold interpenetrated four-connected dia net, respectively. Because compounds 3–5 have one-dimensional (1D) channels, the luminescence properties of 3–5 in different solvents were investigated systematically. Furthermore, compounds 3–5 display highly sensitive, selective, and well-recyclable properties in the detection of nitrobenzene (NB) and 2,4,6-trintrophenol (TNP) as fluorescent sensors.