A novel, facile, simple and convenient oxidative aromatization of Hantzsch 1,4-dihydropyridines to pyridines using polymeric iodosobenzene with KBr
作者:Parvin Kumar
DOI:10.1002/jhet.504
日期:2010.11
An easy, safe, effective and handy method for oxidative aromatization of Hantzsch 1,4‐dihydropyridines catalyzed by hypervalent iodine (iodosobenzene) and potassium bromide to corresponding pyridine derivatives in high‐yields and within short span of time was described. Dealkylation in case of 4‐n‐alkyl substituted 1,4‐dihydropyridines was not obtained. J. Heterocyclic Chem., (2010).
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
NaI readily mediated oxidative aromatization of Hantzsch 1,4-dihydropyridines with hydrogen peroxide at room temperature: A green procedure
作者:D. Shahabi、M. A. Amrollahi、A. A. Jafari
DOI:10.1007/bf03246562
日期:2011.12
The oxidative conversion of 1,4-dihydropyridines to give the corresponding pyridine derivatives in excellent yields was easily effected using the catalytic amount of NaI in combination with H2O2 (30%) as a green external oxidant. The process is highly green wherein the solid products are easily filtered out after the addition of ice-water to the reaction mixture. This non-transition metal catalyst
使用催化量的NaI和H 2 O 2(30%)作为绿色外部氧化剂,可以轻松实现1,4-二氢吡啶的氧化转化,从而以优异的收率得到相应的吡啶衍生物。该方法是高度绿色的,其中在将冰水添加到反应混合物中之后,容易将固体产物滤出。这种非过渡金属催化剂具有成本效益,提供了简单的后处理和易于分离的产物。
Studies on naphthyridines. Part 2. Synthesis of 4-substituted and 6-substituted 1,6-naphthyridin-5(6H)-ones
Ethyl 4-substituted 2-methyl-5-oxo-5,6-dihydro-1,6-naphthyridine-3-carboxylates 3a-h were synthetized in a one-step reaction from diethyl 2,6-diraethylpyridine-3,5-dicarboxylates 1a-h by aminomethinylation with 1,3,5-triazine (2). The 6-substitued derivatives 6a-z,aa-ff could be obtained from diethyl 2-[2-(dimethylamino)-vinyl]-6-methylpyridine-3,5-dicarboxylate (4) either directly or via the isolated