Cobalt and Manganese Salts of p -Aminobenzoic Acid Supported on Silica Gel: A Versatile Catalyst for Oxidation by Molecular Oxygen
作者:Mohammed M. Hashemi、Yusef Ahmadibeni
DOI:10.1007/s00706-002-0534-3
日期:2003.2.1
A 1:1 molar ratio of the cobalt and manganese salts of p -amino benzoic acid supported on silica gel is an effective catalyst for the oxidation of various organic compounds in reasonable yields using molecular oxygen. The catalyst can be reused several times.
An oxidation system to synthesize pyridine derivatives has been developed by oxidation of 1,4-dihydropyridines and polyhydroquinoline derivatives in good yields.
已开发出一种氧化系统,通过氧化1,4-二氢吡啶和多羟基喹啉衍生物,可以高产率合成吡啶衍生物。
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
Ring-contraction of hantzsch esters and their derivatives to pyrroles <i>via</i> electrochemical extrusion of ethyl acetate out of aromatic rings
作者:Xu Liu、Chang Liu、Xu Cheng
DOI:10.1039/d1gc00487e
日期:——
ring-contraction of HEs and theirs pyridinederivatives is developed to obtain polysubstituted pyrroles. This process provides an orthogonal utilization of Hantzsch esters for the well-documented application as side chain or hydrogen donors. The formal transformation shows an extrusion of ethyl acetate out of the pyridine ring in a single step. In addition to the novel transformation, we also discovered the Lewis
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.