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Syntheses, Crystallization, and Spectroscopic Characterization of 3,5-Lutidine N-Oxide Dehydrate
Published on: April 24, 2018
Ultrasound assisted dehydrogenation of 2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxamides
Hamid R Memarian1, Mousa Soleymani
1Catalysis Division, Department of Chemistry, Faculty of Science, University of Isfahan, Isfahan, Iran. memarian@sci.ui.ac.ir
Abstract:
Dehydrogenation of various 2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxamides (THPMs) to 2-oxo-1,2-dihydropyrimidine-5-carboxamides (DHPMs) using tetrabutylammonium peroxydisulfate (TBAPS) as an efficient oxidizing agent under thermal and sono-thermal conditions has been investigated. In contrast to the thermal reaction, a decrease of the amount of oxidant and an increase of the rate of reaction are observed by simultaneously applying heat and ultrasound. The nature of both C-4 and C-5 substituents on the heterocyclic ring influences the rate of reaction under both conditions. The proposed electron-transfer-induced dehydrogenation in this study is supported by conductometric studies.
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