Please use this identifier to cite or link to this item:
Type: Artigo de periódico
Title: Knoevenagel Condensation of Aromatic Aldehydes with Ethyl 4-Chloro-3-oxobutanoate in Ionic Liquids
Author: de Paula, BRS
Zampieri, DS
Zukerman-Schpector, J
Tiekink, ERT
Rodrigues, JAR
Moran, PJS
Abstract: Knoevenagel condensations of aromatic aldehydes with ethyl 4-chloro-3-oxobutanoate catalyzed by morpholine/acetic acid were carried out in ionic liquids to give ethyl 2-chloroacetyl-3-arylpropenoates in 44-84% yield after 0.5 to 2 h at room temperature (25-28 degrees C). These conditions represent a greener protocol for the Knoevenagel condensation than those using refluxing benzene or toluene as solvent. Aromatic aldehydes having aryl groups 4-chlorophenyl, 4-methoxyphenyl, 2-thiofuranyl, 2-furanyl, phenyl and 3,4-methylenedioxyphenyl gave (E)/(Z) diastereomeric ratios of products from 56/44 to 85/15. The two isomers of each compound were separately isolated and characterized. The structure of the (E)-isomer of ethyl 2-chloroacetyl-3-(3',4' methylenedioxyphenyl) propenoate was determined by X-ray crystallography and an unequivocal methodology of (E)/(Z)-structural analysis by C-13 NMR (nuclear magnetic resonance) is presented.
Subject: Knoevenagel condensation
ethyl 4-chloro-3-oxobutanoate
ionic liquid
ethyl (E/Z)-2-chloroacetyl-3-arylpropenoate
Country: Brasil
Editor: Soc Brasileira Quimica
Rights: aberto
Date Issue: 2012
Appears in Collections:Unicamp - Artigos e Outros Documentos

Files in This Item:
File Description SizeFormat 
WOS000304852800006.pdf424.9 kBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.