A facile Tf OH-catalyzed oxidative cyclization of allyl compounds and isocyanide has been developed with the assistance of DDQ, where isocyanide is used as the crucial "N" and "CN" sources. Highly ...A facile Tf OH-catalyzed oxidative cyclization of allyl compounds and isocyanide has been developed with the assistance of DDQ, where isocyanide is used as the crucial "N" and "CN" sources. Highly functionalized 2-cyanopyrroles are constructed efficiently through a new formal [3 + 2] mode, demonstrating diverse reactivity and synthetic utility in organic chemistry. 2-Cyanopyrrole is converted into a nucleobase analogue of Remdesivir and 5H-pyrrolo[2,1-a]isoindole through a three-step or a two-step sequence, respectively. This protocol features broad substrate scope, operational simplicity and good functional group tolerance.展开更多
The safety issues and lower energy density of the lithium metal batteries are the two main challenges that hinder their applications in the fields of electric vehicles and portable devices.In this work,the semi-interp...The safety issues and lower energy density of the lithium metal batteries are the two main challenges that hinder their applications in the fields of electric vehicles and portable devices.In this work,the semi-interpenetrated polyvinylidene fluoride-hexafluoropropylene(PVdF-HFP)-based gel polymer electrolyte was synthesized through UV-curing method by employing the ethoxylated trimethylolpropane triacrylate(ETPTA)monomer.The semi-interpenetrating networks formed by polymerization of ETPTA and the high liquid absorption rate of the PVdF-HFP impart the as-prepared electrolyte with a high room temperature ionic conductivity of 3.17×10-3 s cm^(-1)and a high mechanical strength of 3.46 MPa.LiFePO4 was selected as cathode materials,and the active material loading of the cathode is about 4.2 mg cm-2.The electrolyte shows superior long-term cycling properties(127 mAh g^(-1)after 200 cycles at 0.5 C),excellent rate performance(113 mAh g^(-1)at1 C,80 mAh g^(-1)at 2 C,and the discharge capacity of 135 mAh g^(-1)can be restored when the rate goes back to 0.1 C)as well as good ability to inhibit the growth of lithium dendrite(about 150 h).The facile synthesis strategy and great electrochemical performance of the electrolyte make it a potential candidate for lithium metal batteries.展开更多
α-Keto acids were unprecedentedly employed as novel precursors of nitrile oxides on treatment with copper nitrate,which reacted with maleimides via[3+2]dipolar cycloaddition leading to pharmacologically interesting f...α-Keto acids were unprecedentedly employed as novel precursors of nitrile oxides on treatment with copper nitrate,which reacted with maleimides via[3+2]dipolar cycloaddition leading to pharmacologically interesting fused isoxazolines.This approach offers a unique strategy and complementary method for the convenient generation of alkyl substituted nitrile oxides.展开更多
基金the National Natural Science Foundation of China(Nos.22171178, 21871174, 22071143)Innovation Program of Shanghai Municipal Education Commission (No.2019–01–07–00–09-E00008) for financial support。
文摘A facile Tf OH-catalyzed oxidative cyclization of allyl compounds and isocyanide has been developed with the assistance of DDQ, where isocyanide is used as the crucial "N" and "CN" sources. Highly functionalized 2-cyanopyrroles are constructed efficiently through a new formal [3 + 2] mode, demonstrating diverse reactivity and synthetic utility in organic chemistry. 2-Cyanopyrrole is converted into a nucleobase analogue of Remdesivir and 5H-pyrrolo[2,1-a]isoindole through a three-step or a two-step sequence, respectively. This protocol features broad substrate scope, operational simplicity and good functional group tolerance.
基金financially supported by the Natural Science Foundation of Beijing Municipal(No.L182062)the talents project of Beijing Municipal Committee Organization Department(No.2018000021223ZK21)+1 种基金the Yue Qi Young Scholar Project of China University of Mining&Technology(Beijing)(No.2017QN17)the Fundamental Research Funds for the Central Universities(Nos.2020XJJD01 and 2020YJSJD01)。
文摘The safety issues and lower energy density of the lithium metal batteries are the two main challenges that hinder their applications in the fields of electric vehicles and portable devices.In this work,the semi-interpenetrated polyvinylidene fluoride-hexafluoropropylene(PVdF-HFP)-based gel polymer electrolyte was synthesized through UV-curing method by employing the ethoxylated trimethylolpropane triacrylate(ETPTA)monomer.The semi-interpenetrating networks formed by polymerization of ETPTA and the high liquid absorption rate of the PVdF-HFP impart the as-prepared electrolyte with a high room temperature ionic conductivity of 3.17×10-3 s cm^(-1)and a high mechanical strength of 3.46 MPa.LiFePO4 was selected as cathode materials,and the active material loading of the cathode is about 4.2 mg cm-2.The electrolyte shows superior long-term cycling properties(127 mAh g^(-1)after 200 cycles at 0.5 C),excellent rate performance(113 mAh g^(-1)at1 C,80 mAh g^(-1)at 2 C,and the discharge capacity of 135 mAh g^(-1)can be restored when the rate goes back to 0.1 C)as well as good ability to inhibit the growth of lithium dendrite(about 150 h).The facile synthesis strategy and great electrochemical performance of the electrolyte make it a potential candidate for lithium metal batteries.
基金This work was supported by the National Natural Science Foundation of China(21871174,22171178,21971159)Innovation Program of Shanghai Municipal Education Commission(2019-01-07-00-09-E00008).The authors thank Prof.Chang-Hua Ding and Dr Mingchun Gao for their helpful discussions.Also,many thanks to Ms Jianjian Zha and Mr Shaohang Lu for performing the experiments for the revision.
文摘α-Keto acids were unprecedentedly employed as novel precursors of nitrile oxides on treatment with copper nitrate,which reacted with maleimides via[3+2]dipolar cycloaddition leading to pharmacologically interesting fused isoxazolines.This approach offers a unique strategy and complementary method for the convenient generation of alkyl substituted nitrile oxides.
