AgN<sub>3</sub>-Catalyzed Hydroazidation of Terminal Alkynes and Mechanistic Studies
作者:Shanshan Cao、Qinghe Ji、Huaizhi Li、Maolin Pang、Haiyan Yuan、Jingping Zhang、Xihe Bi
DOI:10.1021/jacs.0c00836
日期:2020.4.15
hydroazidation of alkynes is the most straightforward way to access vinyl azides - versatile building blocks in organic synthesis. We previously realized such a fundamental reaction of terminalalkynes using Ag2CO3 as a catalyst. However, the high catalyst loading seriously limits its practicality, and moreover the exact reaction mechanism remains unclear. Here, on the basis of X-ray diffraction studies on the
Visible-Light-Driven Synthesis of 4-Alkyl/Aryl-2-Aminothiazoles Promoted by In Situ Generated Copper Photocatalyst
作者:Wen-Long Lei、Tao Wang、Kai-Wen Feng、Li-Zhu Wu、Qiang Liu
DOI:10.1021/acscatal.7b02818
日期:2017.11.3
Room-temperature synthesis of 4-alkyl/aryl-2-aminothiazoles from vinyl azides and ammonium thiocyanate was accomplished with the aid of copper salts and blue LED irradiation. Mechanism investigation indicates that in situ-formed Cu(NCS)2– plays dual important roles in the reaction: (1) as the photocatalyst to activate vinyl azides, (2) as the Lewis acid catalyst to promote ring opening of 2H-azirines
Silver-Catalyzed Tandem Hydroazidation/Alkyne–Azide Cycloaddition of Diynes with TMS-N<sub>3</sub>: An Easy Access to 1,5-Fused 1,2,3-Triazole Frameworks
作者:Yongquan Ning、Nannan Wu、Haifeng Yu、Peiqiu Liao、Xingqi Li、Xihe Bi
DOI:10.1021/acs.orglett.5b00784
日期:2015.5.1
A general cascade hydroazidation and alkyne-azide 1,3-dipolar cycloaddition of diynes using silver catalysis is reported. A wide variety of diynes participated in the reaction with trimethylsilyl azide (TMS-N-3) in the presence of H2O, affording the corresponding 1,5-fused-1,2,3-triazoles in good-to-excellent yields. This unprecedented protocol is operationally simple with a broad substrate scope, good functional group tolerance, and high reaction efficiency, thus providing easy access to various fused 1,2,3-triazoles.