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Multinary intermetallic compounds with rich chemical compositions enable one to achieve a logical design for desired materials based on the required function. In this work, we have demonstrated a step-by-step strategy to design a quaternary intermetallic compound that exhibits highly active and stable performance for the hydrogen evolution reaction (HER). With binary intermetallic TaCo2 as the starting point, the minor inclusion of a ductile Cu element in TaCo2 to form ternary TaCu0.25Co1.75 can substantially lower the degradation rate from ca. 20% to 5% after sintering treatment (i.e., enhance connectivity between particles). However, the overpotential at a current density of 10 mA cm−2 (η10) increases by ca. 20 mV from TaCo2 to TaCu0.25Co1.75. Further incorporation of a HER active Ru element to cast quaternary TaCu0.125Ru0.125Co1.75 can decrease ca. 70 mV of η10 while maintaining long-term stability. This proves that one can design functional intermetallic compounds intentionally, which may be extended to different fields of application. [ABSTRACT FROM AUTHOR]

We report the design and synthesis of a redox-active thianthrenium-containing sulfoximination reagent. Photo-catalyzed acetoxysulfoximination of styrene with various functional groups is described. Preliminary mechanistic studies indicated that the sulfoximination reagent (2aa) received a single electron transfer (SET) from the photo-excited Ir(ppy)3 catalyst to produce a sulfoximidoyl radical as a key intermediate in this transformation. [ABSTRACT FROM AUTHOR]

The high performance of the photoelectrochemical (PEC) properties of AuNCs can be achieved with 6-aza-2-thio-thymine–AuNCs (ATT–AuNCs) as a photoactive material. The ATT–AuNCs yielded a cathodic photocurrent density as high as 88 μA cm−2 with O2 as electron acceptor, which is three orders of magnitude higher than those of other AuNCs in aqueous solutions. Moreover, ATT–AuNCs also show a higher carrier density, shorter Debye length, and smaller depletion layer width than those of reported AuNCs. This work not only reveals the PEC performance and mechanism of ATT–AuNCs, but also establishes a framework for in-depth design and studying the PEC performance of AuNCs. [ABSTRACT FROM AUTHOR]

Herein, we have synthesized successfully a three-dimensional/two dimensional (3D/2D) core–shell Cu2O@Fe–Ni3S2 nanoflower on copper foam at room temperature. Remarkably, by virtue of rich active sites and vacancies, large surface area, high conductivity and close contact with the electrolyte, the Cu2O@Fe–Ni3S2 catalyst exhibits superior stability and oxygen evolution reaction performance. [ABSTRACT FROM AUTHOR]

A new all-hydrocarbon macrocycle, cyclo[8](1,3-(4,6-dimethyl)benzene) (CDMB-8) has been reported. As prepared, it exists in Cs symmetry and shows no interaction with fullerenes (e.g., C60 or C70). High temperature (573 K) treatment induces thermal conversion of the material to an isomeric conformer with D4d symmetry as a receptor for fullerene separation. [ABSTRACT FROM AUTHOR]

This feature article summarises recent contributions of the authors in the area of anion-induced supramolecular self-assembly. It is based on the chemistry of a set of tetracationic imidazolium macrocycles, specifically the so-called ‘Texas-sized’ molecular box, cyclo[2](2,6-di(1H-imidazol-1-yl)pyridine)[2](1,4-dimethylenebenzene) (14+), and its congeners, cyclo[2](2,6-di(1H-imidazol-1-yl)pyridine)[2](1,2-dimethylenebenzene) (24+), cyclo[2](2,6-di(1H-imidazol-1-yl)pyridine)[2](1,3-dimethylenebenzene) (34+), and cyclo[2](2,6-di(1H-imidazol-1-yl)pyridine)[2](2,6-dimethylenepyridine) (44+). These systems collectively have been demonstrated as being versatile building blocks that interact with organic carboxylate or sulfonate anions, as well as substrates (e.g., neutral molecules or metal cations). Most work to date has been carried out with 14+, a system that has been found to support the construction of a number of stimuli responsive self-assembled ensembles. This macrocycle and others of the ‘Texas-sized’ box family also show the potential to react as carbene precursors and to undergo post-synthetic modification (PSM) to produce new functional macrocycles, such as trans- and cis-cyclo[2]((Z)-N-(2-((6-(1H-imidazol-1-yl)pyridin-2-yl)amino)vinyl)formamide)[2](1,4-bismethylbenzene) (52+ and 62+, respectively). On the basis of the work reviewed in this Feature article, we propose that the imidazolium macrocycles 14+–44+ can be considered as useful tools for the construction of ensembles with environmentally responsive features, including control over self-assembly and an ability to undergo precursor-specific PSM. [ABSTRACT FROM AUTHOR]

A series of π-conjugated 3,10-dialkyl-dinaphtho[1,2-b:2′,1′-d]chalcogenophenes incorporating S, Se, and Te as the central chalcogen atom was newly synthesized, and their optoelectronic and charge-transport properties were systematically investigated. High carrier mobilities of up to 4.7 cm2 V−1 s−1 were achieved for solution-processed organic field-effect transistors using these materials as p-channel organic semiconductors. [ABSTRACT FROM AUTHOR]

An efficient manganese(II)/O2-promoted oxidative radical cascade reaction was developed for the modular synthesis of multi-substituted isoquinolines from easily accessible vinyl isocyanides and boronic acids. [ABSTRACT FROM AUTHOR]

A bioinspired "point-and-shoot" molecular strategy is described for engineering noncovalent aptamers via K+-induced reassembly of a split G-quadruplex sequence at the end of monomeric aptamers. This design compensates for insufficient cell recognition of monovalent aptamers in biological environments and minimizes structure-induced nonspecific cell binding, expending the aptamer toolbox available for complex systems. [ABSTRACT FROM AUTHOR]

The unique reactivity of indolyl-substituted p-QMs as a new type of two-carbon synthon has been explored for the first time in a novel iron(III)-catalyzed tandem annulation. This (2+2) annulation/retro-4π electrocyclization/imino-Nazarov cyclization cascade reaction is characterized by an unusual structural reconstruction of indolyl-substituted p-QMs, leading to an expeditious assembly of synthetically important functionalized cyclopenta[b]indoles. [ABSTRACT FROM AUTHOR]

The unified Ir-catalyzed enantioselective allylic substitution reactions of silyl enol ethers derived from ketones and α,β-unsaturated ketones with branched, racemic allylic alcohols are described. This transformation is catalyzed by the Carreira system and proceeds without fluoride, and with high ee and b : l ratio. The synthetic utility of this method was illustrated by the concise enantioselective total synthesis of marine natural products calyxolane A, B and by the assignment of the absolute configuration of calyxolane A. [ABSTRACT FROM AUTHOR]

A robust hafnium-based metal organic framework, Hf-PBTA, with sensitive and self-calibrating dual-emissive fluorescence response towards sulfite and sulfonic derivatives, including antibiotic sulfamethazine, has been developed, which shows fast detection of sulfite ions at a concentration as low as 76 ppb. The opposite response tendency from two radiative pathways towards aromatic sulfonic molecules and sulfite anions stems from the synergistic effect of the pyridine protonation effect, π–π stacking interaction and intramolecular twist motion. [ABSTRACT FROM AUTHOR]

We realized that tailoring the pore size/geometry and chemistry, by virtue of alkynyl or naphthalene replacing phenyl within a series of isomorphic MOFs, can optimize methane storage working capacities, affording an exceptionally high working capacity of 203 cm3 (STP) cm−3 at 298 K and 5–80 bar. [ABSTRACT FROM AUTHOR]

A novel metal–organic framework, ZJU-196, with extraordinary acid–base resistant stability has been successfully synthesized, exhibiting highly efficient separation of acetylene from C2H2/CO2 mixtures under ambient conditions. [ABSTRACT FROM AUTHOR]

We report a cerium metal–organic framework (ZJU-136-Ce) for the turn-on fluorescence sensing of AA. The fluorescence enhancement is attributed to the specific redox reaction between AA and Ce4+. The detection limit of AA reaches 7 nM, showing its potential for AA detection in the environmental industry and clinical medicine. [ABSTRACT FROM AUTHOR]

Cyclopentadithiophene and methyl-2,5-dibromobenzoate have been copolymerised via palladium complex catalysed direct arylation. The methyl ester group in the benzoate unit is converted to the carboxyl group via saponification. The polymers are mixed with Si nanoparticles for use as conducting binders in the fabrication of an anode electrode in lithium ion batteries. The battery with the electrode incorporating the saponified polymer shows much higher specific capacity of up to 1820 mA h g−1 (total weight) and a higher stability compared with the battery including the polymer before the saponification. [ABSTRACT FROM AUTHOR]

A highly stable amino-coordinated metal–organic framework ZJU-198 has been synthesized and structurally characterized, exhibiting high CO2 uptake of 105.8 cm3 cm−3 while blocking off N2 adsorption at 1.0 bar and 298 K, attributed to the unique pore window sizes. [ABSTRACT FROM AUTHOR]

A novel copper-catalyzed difluoromethylation of 2- or 3-propargylamide-substituted indoles with ICF2CO2Et via a radical cascade cyclization process is described. A wide substrate scope is compatible with the reaction conditions to synthesize mono- and bis-difluoromethylated indoloazepinone derivatives, which contain a seven-membered ring. [ABSTRACT FROM AUTHOR]

A near-infrared luminescent metal–organic framework Nd0.866Yb0.134BTB was developed as a self-calibrated thermometer in the physiological range. Its features include high sensitivity and resolution, and good biocompatibility, making such a material useful for biomedical applications. [ABSTRACT FROM AUTHOR]

A porous Ni(II)-MOF, which was constructed from a new bent fluorene-bridged ligand and NiCl2 under solvothermal conditions, can reversibly uptake organic solvent molecules and iodine species in a single-crystal-to-single-crystal (SC–SC) fashion. Furthermore, the obtained I2⊂Ni(II)-MOF can be a highly active heterogeneous catalyst to promote solvent-free silylcyanation of aromatic aldehydes under mild conditions. [ABSTRACT FROM AUTHOR]

A cationic robust Zr-cluster-based metal–organic framework has been developed for the efficient removal of Cr2O72− from aqueous solutions. [ABSTRACT FROM AUTHOR]