TiF<sub>4</sub>-catalyzed direct amidation of carboxylic acids and amino acids with amines
作者:Abdulkhaliq A. Alawaed、P. Veeraraghavan Ramachandran
DOI:10.1039/d3ob01943h
日期:——
Unlike other metal fluorides, catalytic titanium tetrafluoride enhances the direct amidation of aromatic and aliphatic carboxylicacids and N-protected amino acids in refluxing toluene. While aromatic acids were converted to amides with 10 mol% of the catalyst within 24 h, aliphatic acids underwent a faster reaction (12 h), with lower catalyst loading (5 mol%). This protocol is equally efficient with
Niphathesine C and related pyridine alkaloids are well known natural products with interesting antimicrobial activities, characterized by a pyridine ring and a lipophilic side chain with a terminal nitrogen‐containing functional group. This paper describes the synthesis of analogues of these alkylpyridine alkaloids with variation of the heterocyclic ring and the terminal functional group. Key steps
Niphathesine C 和相关的吡啶生物碱是众所周知的具有有趣抗菌活性的天然产物,其特征在于一个吡啶环和一个带有末端含氮官能团的亲脂侧链。本文描述了这些烷基吡啶生物碱的杂环和末端官能团变化的类似物的合成。合成的关键步骤是适当的芳基碘化物与 undec-10-ynol 或 undec-10-ynoic 酸衍生物的 Sonogashira 反应。所得化合物在琼脂扩散试验中针对几种细菌和真菌进行了测试。
Carboxyl activation via silylthioesterification: one-pot, two-step amidation of carboxylic acids catalyzed by non-metal ammonium salts
作者:Angus A. Lamar、Lanny S. Liebeskind
DOI:10.1016/j.tetlet.2015.09.050
日期:2015.10
The first organo-catalyzed silylthioesterification of a carboxylic acid and a commercially available mercaptoorganosilane results in the in situ production of an O-silylthionoester. Subsequent amine addition forms amides in an operationally simple one-pot procedure without removal of water. The scope and efficiency of these reactions with respect to the catalyst, carboxylic acid, amine, [Si-S] moiety, and solvent are investigated. A number of functionalities are tolerated in the two-step amidation including alkene, alkyne, alkyl and aryl halides, benzylic ethers, and heterocycles with free coordinating sites. (C) 2015 Elsevier Ltd. All rights reserved.