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The trifluoromethyl group widely prevails in pharmaceutical and agrochemical compounds, while accompanying by the development of new methodologies for trifluoromethylation. Recently, the radical trifluoromethylation by photoredox catalysis has emerged. This Article describes several pioneering works and their representative mechanisms via generation of the trifluoromethyl radical based on photoredox processes. [ABSTRACT FROM AUTHOR]

Novel immobilized metallocomplex catalyst based on bio-inspired concept has been developed. The allyl functional group in the anionic chelating ligand reacts with thiols to give the linker for immobilization. The immobilization of the chelating ligand onto amorphous silica supports results in the isolated metal-binding sites giving the coordinatively unsaturated metal center. The biomimetic iron complex-immobilized silica exhibits the catalysis for olefin epoxidation with aqueous H2O2 at ambient temperature. [ABSTRACT FROM AUTHOR]

Molecular containers that provide both stimuli-responsive assembly/disassembly properties and wide-ranging host capabilities in aqueous medium still remain a current synthetic challenge. Herein we report polyaromatic nanocapsules assembled from V-shaped amphiphilic molecules bearing a photoresponsive ortho-dianthrylbenzene unit in water. Unlike previously reported supramolecular capsules and cages, the nanocapsules quickly and quantitatively disassemble into monomeric species by a non-invasive light stimulus through structural conversion from the open to the closed form of the amphiphiles. Regeneration of the nanocapsules is demonstrated by light irradiation or heating of the closed amphiphiles. With the aid of the wide-ranging host capability, the photo-induced release of various encapsulated guest molecules (e.g., Nile red, Cu(II)-phthalocyanine, and fullerene C60) can be achieved by using the present nanocapsule in water. This feature can furthermore be utilized to switch the fluorescence of encapsulated coumarin guests through their controlled release. Photoresponsive molecular capsules that can be used in water are rare. Here, the authors construct polyaromatic nanocapsules via self-assembly from photoswitch-bearing amphiphilic molecules in water. Light induces a structural change in the amphiphiles, triggering the capsule to disassemble into monomers and release encapsulated guests. [ABSTRACT FROM AUTHOR]

Oligo(ethylene oxide)s are known as widely useable yet not very interactive amphiphilic compounds. Here we report that the long amphiphilic oligomers are bound by a polyaromatic capsule in two different manners, depending on the chain length. For instance, the shorter pentamer is crammed into the isolated cavity of the capsule, whereas the longer decamer is threaded into the capsule to form a 1:1 host-guest complex in a pseudo-rotaxane fashion. These unusual bindings occur instantly, spontaneously, and quantitatively even in water at room temperature, with relatively high binding constants (Ka > 106 M-1). Isothermal titration calorimetry (ITC) studies reveal that enthalpic stabilization is a dominant driving force for both of the complexations through multiple host-guest CH-π and hydrogen-bonding interactions. Furthermore, long oligomers with an average molecular weight of 1000 Da (e.g., 22-mer) are also threaded into the capsules to give pseudo-rotaxane-shaped 2:1 host-guest complexes in water, selectively. Molecular capsules typically bind only guests with volumes smaller than their cavities. Here, the authors find that a polyaromatic capsule accommodates linear amphiphilic oligomers in a length-dependent manner, whereas short chains are fully crammed into the cavity, long chains can be incorporated into the capsule in a threaded fashion. [ABSTRACT FROM AUTHOR]

Mimicking biological structures such as fruits and seeds using molecules and molecular assemblies is a great synthetic challenge. Here we report peanut-shaped nanostructures comprising two fullerene molecules fully surrounded by a dumbbell-like polyaromatic shell. The shell derives from a molecular double capsule composed of four W-shaped polyaromatic ligands and three metal ions. Mixing the double capsule with various fullerenes (that is, C60, C70 and Sc3N@C80) gives rise to the artificial peanuts with lengths of ∼3 nm in quantitative yields through the release of the single metal ion. The rational use of both metal-ligand coordination bonds and aromatic-aromatic π-stacking interactions as orthogonal chemical glue is essential for the facile preparation of the multicomponent, biomimetic nanoarchitectures. [ABSTRACT FROM AUTHOR]