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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]