fulltext.study @t Gmail

Keggin heteropolyacid-based catalysts for the preparation of substituted ethyl β-arylaminocrotonates, intermediates in the synthesis of 4-quinolones

Paper ID Volume ID Publish Year Pages File Format Full-Text
44311 46014 2006 8 PDF Available
Title
Keggin heteropolyacid-based catalysts for the preparation of substituted ethyl β-arylaminocrotonates, intermediates in the synthesis of 4-quinolones
Abstract

Catalysts based on tungstophosphoric and molybdophosphoric acids supported on SiMCM-41 and amine-functionalized SiMCM-41 were obtained. They were characterized by FT-IR and 31P NMR spectroscopies, and their acidity was determined by potentiometric titration with n-butylamine. The undegraded Keggin structure was observed when the heteropolyacids (HPA) are supported on SiMCM-41, and there was a partial degradation to a lacunar species on the amine-functionalized carrier. Also, the acidity of the latter catalysts was lower. The supported Keggin heteropolyacid catalysts are used for the preparation of different substituted ethyl β-arylaminocrotonates, intermediates in the synthesis of 4-quinolones, from substituted anilines and ethyl acetoacetate. The products were obtained with high selectivity. The effect of the different nature of the aniline substitutes was observed. For this Conrad–Limpach reaction, the activity of the prepared catalysts agrees with the different characteristics of the supported heteropolyacids, the yield being higher for the SiMCM-41 supported catalysts.

Keywords
Keggin HPA; SiMCM-41; Amine-SiMCM-41; Catalysts; Conrad–Limpach reaction; Substituted anilines; Ethyl acetoacetate; Ethyl β-arylaminocrotonates
First Page Preview
Keggin heteropolyacid-based catalysts for the preparation of substituted ethyl β-arylaminocrotonates, intermediates in the synthesis of 4-quinolones
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us
Publisher
Database: Elsevier - ScienceDirect
Journal: Applied Catalysis A: General - Volume 308, 10 July 2006, Pages 153–160
Authors
, , , , , ,
Subjects
Physical Sciences and Engineering Chemical Engineering Catalysis
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us