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Due to the strong electron‐withdrawing nature and high lipophilicity of trifluoromethoxy group (OCF3), methods for introducing OCF3 into organic molecules are in high demand. However, the research area of direct enantioselective trifluoromethoxylation is still in the embryonic stage, with limited enantioselectivity and/or reaction types. Here, we describe the first copper‐catalyzed enantioselective trifluoromethoxylation of propargyl sulfonates using trifluoromethyl arylsulfonate (TFMS) as the trifluoromethoxy source in up to 96 % ee. [ABSTRACT FROM AUTHOR]

Graphite (Gr) has been considered as the most promising anode material for potassium‐ion batteries (PIBs) commercialization due to its high theoretical specific capacity and low cost. However, Gr‐based PIBs remain unfeasible at low temperature (LT), suffering from either poor kinetics based on conventional carbonate electrolytes or K+‐solvent co‐intercalation issue based on typical ether electrolytes. Herein, a high‐performance Gr‐based LT rechargeable PIB is realized for the first time by electrolyte chemistry. Applying unidentate‐ether‐based molecule as the solvent dramatically weakens the K+‐solvent interactions and lowers corresponding K+ de‐solvation kinetic barrier. Meanwhile, introduction of steric hindrance suppresses co‐intercalation of K+‐solvent into Gr, greatly elevating operating voltage and cyclability of the full battery. Consequently, the as‐prepared Gr||prepotassiated 3,4,9,10‐perylene‐tetracarboxylicacid‐dianhydride (KPTCDA) full PIB can reversibly charge/discharge between −30 and 45 °C with a considerable energy density up to 197 Wh kgcathode−1 at −20 °C, hopefully facilitating the development of LT PIBs. [ABSTRACT FROM AUTHOR]

An actinyl peroxide cage cluster, Li48+ mK12(OH) m[UO2(O2)(OH)]60 (H2O) n ( m≈20 and n≈310; U60), discriminates precisely between Na+ and K+ ions when heated to certain temperatures, a most essential feature for K+ selective filters. The U60 clusters demonstrate several other features in common with K+ ion channels, including passive transport of K+ ions, a high flux rate, and the dehydration of U60 and K+ ions. These qualities make U60 (a pure inorganic cluster) a promising ion channel mimic in an aqueous environment. Laser light scattering (LLS) and isothermal titration calorimetry (ITC) studies revealed that the tailorable ion selectivity of U60 clusters is a result of the thermal responsiveness of the U60 hydration shells. [ABSTRACT FROM AUTHOR]

The accurate distribution of countercations (Rb+ and Sr2+) around a rigid, spherical, 2.9‐nm size polyoxometalate cluster, {Mo132}42−, is determined by anomalous small‐angle X‐ray scattering. Both Rb+ and Sr2+ ions lead to shorter diffuse lengths for {Mo132} than prediction. Most Rb+ ions are closely associated with {Mo132} by staying near the skeleton of {Mo132} or in the Stern layer, whereas more Sr2+ ions loosely associate with {Mo132} in the diffuse layer. The stronger affinity of Rb+ ions towards {Mo132} than that of Sr2+ ions explains the anomalous lower critical coagulation concentration of {Mo132} with Rb+ compared to Sr2+. The anomalous behavior of {Mo132} can be attributed to majority of negative charges being located at the inner surface of its cavity. The longer anion–cation distance weakens the Coulomb interaction, making the enthalpy change owing to the breakage of hydration layers of cations more important in regulating the counterion–{Mo132} interaction. [ABSTRACT FROM AUTHOR]

Studying numerous biologically important species simultaneously is crucial to understanding cellular functions and the root causes of related diseases. Direct visualization of endogenous biothiols in biological systems is of great value to understanding their biological roles. Herein, a novel multi‐signal fluorescent probe was rationally designed and exploited for the simultaneous sensing of homocysteine (Hcy), cysteine (Cys), and glutathione (GSH) using different emission channels. This probe was successfully applied to the simultaneous discrimination between and visualization of endogenous Hcy, Cys, GSH, and their transformation in living cells. [ABSTRACT FROM AUTHOR]