A metal-free approach to N-aryl thioamides fromBuntesalts and anilines in DMSO has been developed. This method tolerated a wide range of functional groups on the aromatic ring, providing an ideal way to N-aryl thioamides in good to excellent yields from cheap and easily available starting materials. A plausible mechanism was also proposed based on the X-ray single crystal diffraction, NMR and MS
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.
A chromatography-free and aqueous waste-free process for thioamide preparation with Lawesson’s reagent
作者:Ke Wu、Yichen Ling、An Ding、Liqun Jin、Nan Sun、Baoxiang Hu、Zhenlu Shen、Xinquan Hu
DOI:10.3762/bjoc.17.69
日期:——
After completing the thio-substitution with Lawesson’sreagent, ethanol was found to be effective in the decomposition of the inherent stoichiometric six-membered-ring byproduct from the Lawesson’sreagent to a highly polarized diethyl thiophosphonate. The treatment significantly simplified the following chromatography purification of the desired thioamide in a small scale preparation. As scaling up