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Developing new strategies to enable chemo- and regioselective reductions is an important topic in chemical research. Herein, an efficient and regioselective Pd/IPrBIDEA-catalyzed ring-opening hydrodefluorination of gem-difluorocyclopropanes to access terminal fluoroalkenes is developed. The success of this transformation was attributed to the use of 3,3-dimethylallyl Bpin as a novel hydride donor. DFT calculations suggest that a direct 3,4′-hydride transfer via a 9-membered cyclic transition state is more favorable, which combined with the irreversibility of the reaction enables the unusual selectivity for the less thermodynamically stable terminal alkene isomer. This reaction mode is also applicable to a variety of regioselective allylic and propargyl reductions.

The concurrent incorporation of a germyl fragment and another functional group (beyond the hydrogen atom) across the C═C double bond is a highly appealing yet challenging task. Herein we demonstrate the efficient germyl peroxidation of alkenes with germanium hydrides and tert-butyl hydroperoxide via a copper-catalyzed three-component radical relay strategy. This protocol exhibits excellent functional group tolerance and exquisite chemo- and regioselectivity under mild conditions and represents a rare example of constructing synthetically challenging metal-embedded organic peroxides.

Lithium–oxygen batteries with ultrahigh energy densities have drawn considerable attention as next-generation energy storage devices. However, their practical applications are challenged by sluggish reaction kinetics aimed at the formation/decomposition of discharge products on battery cathodes. Developing effective catalysts and understanding the fundamental catalytic mechanism are vital to improve the electrochemical performance of lithium–oxygen batteries. Here, uniformly dispersed ruthenium nanoparticles anchored on nitrogen-doped reduced graphene oxide are prepared by using an in situpyrolysis procedure as a bifunctional catalyst for lithium–oxygen batteries. The abundance of ruthenium active sites and strong ruthenium–support interaction enable a feasible discharge product formation/decomposition route by modulating the surface adsorption of lithium superoxide intermediates and the nucleation and growth of lithium peroxide species. Benefiting from these merits, the electrode provides a drastically increased discharge capacity (17,074 mA h g–1), a decreased charge overpotential (0.51 V), and a long-term cyclability (100 cycles at 100 mA g–1). Our observations reveal the significance of the dispersion and coordination of metal catalysts, shedding light on the rational design of efficient catalysts for future lithium–oxygen batteries.

The incorporation of a germyl group and another functional fragment across the C═C bond is a challenging task due to the prevailing hydrogermylation reaction. Herein, an efficient copper-catalyzed three-component reaction of alkenes, germanium hydrides, and trimethylsilyl azide has been disclosed. This transformation allows the concomitant introduction of germyl and azide groups across the double bonds in a highly regioselective manner with tert-butyl hydroperoxides as the bystanding oxidant. The resulting β-germyl azides could be easily converted into β-germyl amine and 1,2,3-triazoles of significant value.

To address sluggish sulfur redox kinetic and the "shuttling behavior" of polysulfides in lithium-sulfur batteries (LSBs), CoS2hollow nanospheres tightly anchored on three-dimensional (3D) N-doped biological carbon nanofibers skeleton (CoS2/N-CNFs) are successfully designed as highly-efficient sulfur hosts. The carbon nanofibers obtained by carbonization of bacterial cellulose are interweaved with each other, and can provide a firm 3D conductive skeleton for the low-conductive sulfur cathode. And the N-doping carbon nanofibers skeleton with polar CoS2can achieve synergetic physical/chemical adsorption of polysulfides and effective catalytic conversion, which are contributed to enhance sulfur redox kinetic and effectively suppress the shuttling effect. Moreover, the skeleton with abundant ?OH functional groups achieve strong chemisorption to CoS2, greatly maintaining structural stability during cycling process. Benefitting from the above-mentioned merits, CoS2/N-CNFs@S electrode with high sulfur loading of 74.4% exhibits superior reversible capacity of 497.3 mAh g?1at 0.2 C after 100 cycles with an improved coulombic efficiency of approximately 100%, and the electrode has excellent cycle life with 73% capacity retention over 300 cycles at 0.5 C. This synthesis strategy makes a leading exploration for the application of biological carbon materials in advanced LSBs.

The development of methods for the assembly of 1,2,3-triazoles is an important topic due to the broad applications of this motif in various scientific fields. In this work, we demonstrate that the three-component assembly of α-CF3carbonyls, NaN3, and amines was achieved for the selective construction of a variety of 5-amino NH-1,2,3-triazoles under transition-metal-free and open-air conditions. The method provides a general and operationally simple route to functionalized biologically important molecules including carbohydrates, nucleosides, and peptides and exhibits broad substrate scopes. We further demonstrate that the NH-1,2,3-triazoles can be smoothly converted to the regiospecific N-2 alkylated 1,2,3-triazole products. Mechanistic studies based on experiments and density functional theory calculations showed that this transformation proceeds via defluorination-initiated programmed substitution/cyclization/H-transfer to give the 4,5-difunctionalized captodative NH-1,2,3-triazole product.

V2O3is considered to be a potential anode material due to its large specific capacity and rich resources. Herein, flock‐like V2O3coated with carbon is prepared through a facile and simple solvothermal method followed by annealing at a relatively low temperature. The structure of V2O3/C is composed of porous strips. Due to the unique morphology and structure, the V2O3/C anode material shows excellent electrochemical performance. It delivers a specific discharge capacity of 696 mAh g−1after 100 cycles, which is 95% of the specific discharge capacity (732 mAh g−1) after the sixth cycle. The V2O3/C anode material annealed at 360 °C (V2O3/C‐360) delivers 601 mAh g−1at a current density of 300 mA g−1after 500 cycles. It implies superior cyclic stability of V2O3/C‐360. In addition, the anode also shows excellent rate capability. Specific capacities of approximately 600, 420, and 300 mAh g−1are obtained at the current densities of 0.3, 2, and 5 A g−1, respectively. The large current contribution of the capacitive reveals favorable superior lithium storage kinetics. This anode material presents great application potential in high‐performance lithium‐ion batteries. Flock‐like V2O3coated with carbon (V2O3/C) is prepared by a facile solvothermal method followed by treatment at a relatively low temperature. The unique structure and morphology bring excellent cyclic stability and rate capability for V2O3/C. The outstanding electrochemical performance reveals its great potential as an anode material for Li‐ion batteries.