Hydrogenation is only the beginning: alkyl groups are mildly transferred from alkyl substituted Hantzsch esters to replace the nitro groups of nitro olefins to providetrans-olefins in moderate to excellent yields.
Hydrogenation was only the beginning: Hantzsch esters have now been used to transferalkyl groups to imines under mild catalytic conditions to provide a variety of amines (see scheme). Benzyl, secondary alkyl, and tertiary alkyl groups containing ether, ester, and hydroxy functionalities were transferred successfully. The use of Hantzsch esters as alkylation reagents offers a practical and complementary
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.