Chemoselective oxidation of substituted benzyl alcohols and toluenederivatives has been developed using a flavin photocatalyst, visible light and a suitable additive. Depending on the flavin and the additive, oxidation takes place selectively to the corresponding aldehyde or carboxylicacid. The procedure is also useful for oxidation of secondary alcohols or benzylic methylene‐containing compounds
Herein is described an efficient and chemoselective method for the synthesis of diversely substituted secondary amines in yields up to 98 %. Direct mono-N-alkylation of primary benzylamines and anilines with a wide range of alkyl halides is promoted by a cesium base in the absence of any additive or catalyst. The basicity and solubility of cesium carbonate in anhydrous N,N-dimethylformamide not only
and eco-friendly method for the synthesis of o-nitroarylamine from o-nitroaryl sulfonic acid via ipso nucleophilic aryl substitution by amine is described. The products have been obtained with good yields at room temperature without the assistance of any metal, activating agent, or toxic oxidant. This method is useful for racemization-free synthesis of N-aryl amino acid esters.
Synthesis of Substituted Diphenylamines Under Phase Transfer Catalysis
作者:Edgardo N. Durantini、Stella M. Chiacchiera、Juana J. Silber
DOI:10.1080/00397919608003801
日期:1996.10
Abstract A convenient procedure for the synthesis of N-[(trifluoromethyl) nitrophenyl] substituted anilines by means of a chloro-substitution reactionunder conditions of phase-transfercatalysis (PTC) is reported. The ipso-substitution product is obtained with high yield. This method provides a general procedure for the synthesis of diphenylamines bearing electron-withdrawing groups in both aromatic
anes, which were subjected, without isolation, to various cyclocondensation reactions with CS2, CO2, alkyl isocyanates, acyl chlorides, anhydrides, or esters. A simple, convenient, one-pot procedure provided derivatives of unsymmetrically substituted 1-alkylbenzimidazoles functionalized at C2 in good to excellent yields. The method does not require the use of metals, sensitive catalysts, or pressure