Reduction of arenediazonium salts by tetrakis(dimethylamino)ethylene (TDAE): Efficient formation of products derived from aryl radicals
作者:Mohan Mahesh、John A Murphy、Franck LeStrat、Hans Peter Wessel
DOI:10.3762/bjoc.5.1
日期:——
arenediazonium salts to aryl radical intermediates through a single electron transfer (SET) pathway. Cyclization of the aryl radicals produced in this way led, in appropriate substrates, to syntheses of indolines and indoles. Cascade radical cyclizations of aryl radicalsderivedfrom arenediazonium salts are also reported. The relative ease of removal of the oxidized by-products of TDAE from the reaction
Palladium-Catalysed Intramolecular Direct Arylation of 2-Bromobenzenesulfonic Acid Derivatives
作者:Charles Beromeo Bheeter、Jitendra K. Bera、Henri Doucet
DOI:10.1002/adsc.201200793
日期:2012.12.14
arylation of 2-bromobenzenesulfonic acid derivatives was found to proceed using 1 mol% of palladiumacetate as the catalyst. The influence of the substituents on the phenol moiety of 2-bromobenzenesulfonic acid phenyl esters reveals that electron-donating substituents favour the reaction while electron-withdrawing ones are unfavourable. The reactivity of sulfonamides was also studied and, in all cases
Sulfoxylate Anion Radical-Induced Aryl Radical Generation and Intramolecular Arylation for the Synthesis of Biarylsultams
作者:Joydev K. Laha、Pankaj Gupta
DOI:10.1021/acs.joc.1c03031
日期:2022.3.18
Aryl radical generation from the corresponding aryl halides using an electron donor and subsequent intramolecular cyclization with arenes could be an important advancement in contemporary biaryl synthesis. A green and practically useful synthetic protocol to access diverse six- and seven-membered biarylsultams especially with a free NH group including demonstration of a gram-scale synthesis is reported
使用电子供体从相应的芳基卤化物生成芳基自由基,然后与芳烃进行分子内环化,可能是当代联芳基合成的重要进步。本文报道了一种绿色且实用的合成方案,用于获取各种六元和七元联芳基磺胺类化合物,尤其是具有游离 NH 基团的化合物,包括克级合成的演示。次硫酸根阴离子自由基 (SO 2 –• ),由试剂雕白粉或连二亚硫酸钠 (Na 2 S 2 O 4),被发现是从芳基卤化物形成芳基自由基的关键单电子转移剂,其在分子内芳基化后得到具有良好至优异产率的联芳基磺胺。该方法的特点是产生仍未开发的芳基自由基,使用廉价且易于获得的工业试剂,以及无过渡金属、温和和绿色的反应条件。
A Further Decrease in the Catalyst Loading for the Palladium-Catalyzed Direct Intramolecular Arylation of Amides and Sulfonamides
The direct arylation of N‐substituted o‐bromobenzanilides and benzenesulfonamides via CH bond functionalization has been developed using very low catalyst loadings. This novel cost‐effective and more sustainable method relies on a PCN‐type palladium pincer complex as a highly active palladium source, providing a general and efficientaccess to phenanthridinones, biaryl sultams and related heterocyclic