An Expeditious Oxidative Aromatization of Hantzsch 1,4-Dihydropyridines to Pyridines Using Cetyltrimethylammonium Peroxodisulfate: A Phase Transferring Oxidant
作者:Parvin Kumar、Ashwani Kumar
DOI:10.5012/bkcs.2010.31.8.2299
日期:2010.8.20
A new approach to the use of potassium peroxodisulphate as an oxidizing reagent is proposed and applied to the case of oxidativearomatization of 1, 4-dihydropyridines with cetyltrimethylammonium peroxodisulfate, a phase transfer oxidant. We demonstrate how it is possible to increase the reactivity of potassium peroxodisulphate in the presence of phase transfer catalyst. Dealkylation in case of 4-n-alkyl/n-alkenyl
Iodobenzene diacetate (IBD) catalyzed an quick oxidative aromatization of Hantzsch-1,4-dihydropyridines to pyridines under ultrasonic irradiation
作者:Parvin Kumar、Ashwani Kumar、Khalid Hussain
DOI:10.1016/j.ultsonch.2011.12.021
日期:2012.7
This project was undertaken to demonstrate the potential of iodobenzenediacetate for the oxidative aromatization of Hantzch-1,4-dihydropyridines under ultrasonic irradiation. All reactions were carried out under ultrasonic irradiation and results were compared with traditional method. Sonochemical switching was observed in case of oxidative aromatization of 4-n-alkyl substituted 1,4-DHP. Without sonication
Aromatization of Hantzsch 1,4-Dihydropyridines with I2-MeOH
作者:Jhillu S. Yadav、Basi V. Subba Reddy、Gowravaram Sabitha、Garudammagari S. Kiran Kumar Reddy
DOI:10.1055/s-2000-7613
日期:——
4-Alkyl or aryl substituted Hantzsch1,4-dihydropyridines are aromatized to the corresponding pyridines in high yields by iodine in refluxing methanol. The method tolerates several substituents such as alkyl, benzyl, aryl and heterocyclic groups present in the 4-position of pyridines.
Iodoxybenzoic Acid (IBX): An Efficient and Novel Oxidizing Agent for the Aromatization of 1,4-Dihydropyridines
作者:J. S. Yadav、B. V. Reddy、A. K. Basak、G. Baishya、A. Venkat Narsaiah
DOI:10.1055/s-2005-918519
日期:——
Hantzsch 1,4-dihydropyridines undergo smooth aromatization catalyzed by iodoxybenzoic acid (IBX) to afford the corresponding pyridine derivatives in high yields. All the reactions were carried out in DMSO solvent at 80-85 °C for a period of two to four hours to complete conversion of the substrates.