Rh(III)‐catalyzed C–H activation of N‐protected anilines and chemo‐divergent couplings with acroleins/enones have been realized for synthesis of three classes of heterocycles.The oxidative coupling of N‐pyridylan...Rh(III)‐catalyzed C–H activation of N‐protected anilines and chemo‐divergent couplings with acroleins/enones have been realized for synthesis of three classes of heterocycles.The oxidative coupling of N‐pyridylaniline afforded dihydroquinolones with the acrolein being a major hydrogen acceptor.When the directing group was replaced by pyrimidyl in the same system,redox‐neutral coupling occurred to afford hemiaminal ethers.Oxidative annulation of N‐pyridylanilines with enones using AgBF4 oxidant afforded atropisomeric quinolinium salts.展开更多
Lithium (Li) metal is considered as the ultimate anode choice for developing next-generation high-energy batteries. However, the poor tolerance against moist air and the unstable solid electrolyte interphases (SEI) in...Lithium (Li) metal is considered as the ultimate anode choice for developing next-generation high-energy batteries. However, the poor tolerance against moist air and the unstable solid electrolyte interphases (SEI) induced by the intrinsic high reactivity of lithium bring series of obstacles such as the rigorous operating condition, the poor electrochemical performance, and safety anxiety of the cell, which to a large extent hinder the commercial utilization of Li metal anode. Here, an effective encapsulation strategy was reported via a facile drop-casting and a following heat-assisted cross-linking process. Benefiting from the inherent hydrophobicity and the compact micro-structure of the cross-linked poly(vinylidene-co-hex afluoropropylene) (PVDF–HFP), the as-encapsulated Li metal exhibited prominent stability toward moisture, as well corroborated by the evaluations both under the humid air at 25 °C with 30% relative humidity (RH) and pure water. Moreover, the encapsulated Li metal anode exhibits a decent electrochemical performance without substantially increasing the cell polarization due to the uniform and unblocked ion channels, which originally comes from the superior affinity of the PVDF–HFP polymer toward nonaqueous electrolyte. This work demonstrates a novel and valid encapsulation strategy for humiditysensitive alkali metal electrodes, aiming to pave the way for the large-scale and low-cost deployment of the alkali metal-based high-energy-density batteries.展开更多
基金supported by the National Nature Science Foundation of China(21525208,21472186)the fund for new technology of methanol conversion of Dalian Institute of Chemical Physics(Chinese Academy of Sciences)~~
文摘Rh(III)‐catalyzed C–H activation of N‐protected anilines and chemo‐divergent couplings with acroleins/enones have been realized for synthesis of three classes of heterocycles.The oxidative coupling of N‐pyridylaniline afforded dihydroquinolones with the acrolein being a major hydrogen acceptor.When the directing group was replaced by pyrimidyl in the same system,redox‐neutral coupling occurred to afford hemiaminal ethers.Oxidative annulation of N‐pyridylanilines with enones using AgBF4 oxidant afforded atropisomeric quinolinium salts.
基金This work was supported by National Key Research and Development Program(2016YFA0202500)National Natural Science Foundation of China(21776019)Beijing Natural Science Foundation(L182021).
文摘Lithium (Li) metal is considered as the ultimate anode choice for developing next-generation high-energy batteries. However, the poor tolerance against moist air and the unstable solid electrolyte interphases (SEI) induced by the intrinsic high reactivity of lithium bring series of obstacles such as the rigorous operating condition, the poor electrochemical performance, and safety anxiety of the cell, which to a large extent hinder the commercial utilization of Li metal anode. Here, an effective encapsulation strategy was reported via a facile drop-casting and a following heat-assisted cross-linking process. Benefiting from the inherent hydrophobicity and the compact micro-structure of the cross-linked poly(vinylidene-co-hex afluoropropylene) (PVDF–HFP), the as-encapsulated Li metal exhibited prominent stability toward moisture, as well corroborated by the evaluations both under the humid air at 25 °C with 30% relative humidity (RH) and pure water. Moreover, the encapsulated Li metal anode exhibits a decent electrochemical performance without substantially increasing the cell polarization due to the uniform and unblocked ion channels, which originally comes from the superior affinity of the PVDF–HFP polymer toward nonaqueous electrolyte. This work demonstrates a novel and valid encapsulation strategy for humiditysensitive alkali metal electrodes, aiming to pave the way for the large-scale and low-cost deployment of the alkali metal-based high-energy-density batteries.
