Photochemical Synthesis of s-Triazolo[3,4-b]benzothiazole and Mechanistic Studies on Benzothiazole Formation
摘要:
A general photochemical synthesis of s-triazolo[3,4-b]benzothiazoles from 4,5-disubstituted 1,2,4-triazole-3-thione is described. Steady photolysis, quantum yield determination, and laser flash photolysis experiments have been carried out. An intramolecular electron transfer mechanism has been proposed.
One-pot copper-catalyzed synthesis of 2-substituted benzothiazoles from 2-iodoanilines, benzyl chlorides and elemental sulfur
作者:Zhao Yang、Renhe Hu、Xiaotong Li、Xin Wang、Ren Gu、Shiqing Han
DOI:10.1016/j.tetlet.2017.05.004
日期:2017.6
An efficient one-pot three-component reaction of 2-iodoanilines, benzyl chlorides and elementalsulfur to form 2-substituted benzothiazoles in satisfactory yields (up to 98%) has been described. The reaction tolerated a wide range of functional groups on the aromatic ring. And heterocycle methylene chlorides substrates were also found to be compatible.
Riboflavin as Photoredox Catalyst in the Cyclization of Thiobenzanilides: Synthesis of 2-Substituted Benzothiazoles
作者:Lydia M. Bouchet、Adrián A. Heredia、Juan E. Argüello、Luciana C. Schmidt
DOI:10.1021/acs.orglett.9b04384
日期:2020.1.17
Benzothiazoles are synthesized from thiobenzanilides using riboflavin as a photosensitizer and potassium peroxydisulfate as a sacrificial oxidizing agent under visible light irradiation. The methodology accepts a broad range of functional groups and affords the 2-substitutedbenzothiazoles by transition-metal-free organic photoredoxcatalysis under very mild conditions.
Copper‐Catalyzed Aerobic Oxidation of Amines to Benzothiazoles via Cross Coupling of Amines and Arene Thiolation Sequence
作者:Jihyeon Kim、Kyungsoo Oh
DOI:10.1002/adsc.202000598
日期:2020.9.8
A one‐pot three‐component synthesis of benzothiazoles has been developed using the copper‐catalyzed aerobic cross coupling of amines followed by arene thiolation using elemental sulfur. The dual roles of elemental sulfur and CuCl(OH)‐TMEDA in the aerobic amine oxidation and the aniline thiolation enable the facile access to benzothiazole derivativesfrom readily available starting materials. The operational
The disproportionation of elemental sulfur at moderate temperatures is investigated in the redox condensation involving o‐halonitrobenzenes 1 and benzylamines 2. As a redox moderator, elemental sulfur plays the dual role of both electron donor and acceptor, generating its lowest and highest oxidation states: S−2 (sulfide equivalent) in benzothiazole 3 and S+6 (sulfate equivalent) in sulfamate 4, and
A simple approach to benzothiazoles from 2-chloronitrobenzene, elemental sulfur, and aliphatic amine under solvent-free and catalyst-free conditions
作者:Yao Tong、Qiang Pan、Zengqiang Jiang、Dazhuang Miao、Xuesong Shi、Shiqing Han
DOI:10.1016/j.tetlet.2014.08.037
日期:2014.10
A novel solvent-free and catalyst-free synthesis of benzothiazoles from 2-chloronitrobenzene, elemental sulfur, and aliphatic amine has been developed. The reaction tolerated a wide range of functionalities, and various benzothiazoles were synthesized in moderate to good yields in the absence of external oxidant or reductant. (C) 2014 Elsevier Ltd. All rights reserved.