1,7-Palladium Migration via C−H Activation, Followed by Intramolecular Amination: Regioselective Synthesis of Benzotriazoles
摘要:
A novel 1,7-palladium migration-cyclization-dealkylation sequence for the regioselective synthesis of benzotriazoles has been developed. These reactions proceed in excellent yields with high regioselectivities. The mechanism of the reaction has also been investigated.
Electrophotocatalysis with a Trisaminocyclopropenium Radical Dication
作者:He Huang、Zack M. Strater、Michael Rauch、James Shee、Thomas J. Sisto、Colin Nuckolls、Tristan H. Lambert
DOI:10.1002/anie.201906381
日期:2019.9.16
electrophotocatalytic oxidation platform. This chemistry employs a trisaminocyclopropenium (TAC) ion catalyst, which is electrochemically oxidized to form a cyclopropenium radical dication intermediate. The radical dication undergoes photoexcitation with visible light to produce an excited-state species with oxidizing power (3.33 V vs. SCE) sufficient to oxidize benzene and halogenated benzenes via single-electron
可见光光催化和电催化是促进化学反应的两种强大策略。在这里,这两种模式结合在电光催化氧化平台中。该化学过程采用三氨基环丙烯 (TAC) 离子催化剂,通过电化学氧化形成环丙烯自由基阳离子中间体。自由基阳离子在可见光下进行光激发,产生具有氧化能力(3.33 V vs. SCE)的激发态物质,足以通过单电子转移(SET)氧化苯和卤代苯,从而导致 CH/NH 与唑类偶联。提供了光激发物质的强氧化行为的基本原理,同时通过顺式2,6-二甲基哌啶部分的特定构象合理化了催化剂的稳定性。
[3 + 2] Cycloaddition of azides with arynes formed<i>via</i>C–H deprotonation of aryl sulfonium salts
作者:Xing-Wei Gu、Yan-Hua Zhao、Xiao-Feng Wu
DOI:10.1039/d3gc02052e
日期:——
Herein, we developed a new methodology of using aryl sulfonium salts as the aryne precursor for [3 + 2] cycloaddition reactions with azides. The reaction using readily available arenes as the feedstock features excellent atom economy, environmental friendliness and high functional group tolerance. Moreover, due to the excellent performance of the gram-scale reaction, deuterium labeling result and derivatization