A porous Cu(ii)-MOF shows an adsorption of 6.6 wt% of H at 77 K and 62 bar and a very high 60 wt% of CO at 298 K and 32 bar. When air is bubbled into a suspension of the activated MOF in the presence of different epoxides at room temperature, the CO in air is readily converted into the corresponding cyclic carbonates.

The solvothermal reaction of Zn(NO)·6HO and a linear dicarboxylate ligand HL, in the presence of urotropine in N,N'-dimethylformamide (DMF), gives rise to a new porous two-dimensional (2D) coordination network, {[Zn(L)(urotropine)]·2DMF·3HO} (1), with hxl topology. Interestingly, framework 1 exhibits excellent emission properties owing to the presence of naphthalene moiety in the linker HL, that can be efficiently suppressed by subtle quantity of nitro explosives in aqueous medium. Furthermore, presence of urotropine molecules bound to the metal centers, 1 is found to be an excellent heterogeneous catalyst meant for atom-economical C-C bond-forming Baylis-Hillman reactions. Additionally, crystals of 1 undergo complete transmetalation with Cu(II) to afford isostructural 1. Moreover, the 2D framework of 1 allows replacement of urotropine molecules by 4,4'-azopyridine (azp) linker resulting in a three-dimensional (3D) metal-organic framework, {[Zn(L)(azp)]·4DMF 2HO} (2). The 1→2 transformation takes place in single-crystal-to-single crystal manner supported by powder X-ray diffraction, atomic force microscopy, high-resolution transmission electron microscopy, and morphological studies. Remarkably, during this 2D→3D transformation, the original trinuclear [Zn(COO)] secondary building unit changes to a mononuclear node, which is unprecedented.

A novel 2(2′-hydroxyphenyl) benzothiazole-based cryptand (L) exhibits high fluorescence intensity in the presence of Zn2+ ions by stopping the excited state intramolecular proton transfer (ESIPT) process with a detection limit of 0.20 μM.

A series of three positional isomers of organic cages namely o -OC, m -OC, and p -OC, have been self-assembled using dynamic covalent chemistry. Their room temperature controlled fabrication with palladium gives ultrafine diameter (1–2 nm) of palladium nanoparticles (Pd NPs). We observed that the shape-flexibility of cages have great impact on the formation of Pd NPs. Theoretical calculations reveals that theoretically obtainable size of Pd NPs for each cage which was complementary to the experimental results. Theoretical studies indicate that the driving forces for the specific orientational preference may be ascribed to subtle variations on the level of π–π interactions, which ultimately governs the growth of Pd NPs therein. It is the first example of shape-flexible synthesis of organic cages where flexibility governs the nanoparticle growth. Pd NPs have shown excellent catalysis of Tsuji–Trost allylation at room temperature and pressure in water.

A robust paddle-wheel Cu(II)-based metal-organic framework (MOF) 1, having dual functionalities, namely, Lewis acid and basic sites, has been explored as a heterogeneous catalyst. This MOF, because of its large void volume (10298 Å, 67.6%), large surface area (1480 m/g), and high thermal stability, encouraged us to see its applicability in two catalytic reactions, namely, oxidative C-O coupling (cross-dehydrogentaive coupling reaction) involving direct C-H activation and Friedländer reaction under solvent free and ambient conditions. This study demonstrates the green aspect of MOFs in coupling reactions because of the simplified recovery, shorter reaction time, minimum waste, and smooth activation of the C-H bond, which is very challenging in synthetic chemistry.

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The evolution of the chemical and pharmaceutical industry requires effective and less energy-intensive separation technologies. Engineering smart materials at a large scale with tunable properties for molecular separation is a challenging step to materialize this goal. Herein, we report thin film composite membranes prepared by the interfacial polymerization of porous organic cages (POCs) (RCC3 and tren cages). Ultrathin crosslinked polycage selective layers (thickness as low as 9.5 nm) are obtained with high permeance and strict molecular sieving for nanofiltration. A dual function is achieved by combining molecular separation and catalysis. This is demonstrated by impregnating the cages with highly catalytically active Pd nanoclusters ( ~ 0.7 nm). While the membrane promotes a precise molecular separation, its catalytic activity enables surface self-cleaning, by reacting with any potentially adsorbed dye and recovering the original performance. This strategy opens opportunities for the development of other smart membranes combining different functions and well-tailored abilities.

Porous shape-persistent organic cages can anchor metal nanoparticles either inside the cavity or in the external cavity generated through self-assembly. The size of these nanoparticles range within 1-2 nm depending...