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Efficient and energy‐saving separation of benzene isomers bearing a diverse range of functional groups is a great challenge due to their overlapping physicochemical properties. Here, we report the successfully use of a water‐soluble pillar[5]arene (WP5) as a multifunctional material for the separation and detection of meta/ortho‐substituted benzene isomers in water. A liquid‐liquid extraction strategy was used for the separation of these benzene isomers based on their different affinity for WP5 in water. The selectivities for the meta over the ortho isomer for xylenes, chlorotoluene, and bromotoluene was 88.6 %, 88.3 %, and 95.0 % respectively, in one extraction cycle. Furthermore, a fluorescence indicator system based on WP5 and a fluorescent dye molecule (10‐methylacridinium, D) was adopted and exhibited significant fluorescence and optical discrimination upon the addition of meta‐ compared to ortho‐xylene, which implies that a simple "turn‐on" detection can be performed prior to engaging in the separation process. [ABSTRACT FROM AUTHOR]

Herein, we report the synthesis of a new class of functional silver nanoclusters (AgNCs) capped with pillar[5]arene (P5)‐based host ligands. These NCs are readily prepared through direct synthesis or ligand exchange synthesis and are stable at room temperature for over 4 months. The pillar[5]arene‐stabilized NCs (Ag29(LA‐P5)12(TPP)2) endorse reversible host–guest interactions with neutral alkylamines and cationic quaternary ammonium guests. This results in the formation of spherical assemblies with unparalleled changes in their optical properties including an astonishing circa 2000‐fold luminescence enhancement. This is the highest luminescence enhancement ratio reported so far for such atomically precise NCs. Our synthetic protocol paves the way for the preparation of a new generation of metal nanoclusters protected by macrocyclic ligands with molecular recognition and selectivity toward specific guests. [ABSTRACT FROM AUTHOR]

Engineering membranes for molecular separation in organic solvents is still a big challenge. When the selectivity increases, the permeability tends to drastically decrease, increasing the energy demands for the separation process. Ideally, organic solvent nanofiltration membranes should be thin to enhance the permeant transport, have a well-tailored nanoporosity and high stability in harsh solvents. Here, we introduce a trianglamine macrocycle as a molecular building block for cross-linked membranes, prepared by facile interfacial polymerization, for high-performance selective separations. The membranes were prepared via a two-in-one strategy, enabled by the amine macrocycle, by simultaneously reducing the thickness of the thin-film layers (<10 nm) and introducing permanent intrinsic porosity within the membrane (6.3 Å). This translates into a superior separation performance for nanofiltration operation, both in polar and apolar solvents. The hyper-cross-linked network significantly improved the stability in various organic solvents, while the amine host macrocycle provided specific size and charge molecular recognition for selective guest molecules separation. By employing easily customized molecular hosts in ultrathin membranes, we can significantly tailor the selectivity on-demand without compromising the overall permeability of the system. Engineering thin membranes for molecular separation with well tailored nanoporosity and which can withstand harsh conditions is still a big challenge. Here, the authors introduce a trianglamine macrocycle as a molecular building block for cross-linked membranes, prepared by facile interfacial polymerization, for high performance selective separations. [ABSTRACT FROM AUTHOR]