Silica Gel–Supported bis(Trimethylsilyl) Chromate: Oxidation of 1,4‐Dihydropyridines to Pyridines
摘要:
An efficient and convenient method for the oxidation of 1,4-dihydropyridines mediated by silica gel-supported bis(trimethylsilyl) chromate in refluxing CH 2 Cl 2 is reported.
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.
One-Pot Synthesis and Aromatization of 1,4-Dihydropyridines in Refluxing Water
作者:Guan-Wu Wang、Jing-Jing Xia
DOI:10.1055/s-2005-870022
日期:——
A series of 1,4-dihydropyridines were synthesized in an environmentally benign method, by reacting aldehydes with acetoacetate esters or acetylacetone and ammonium acetate in refluxing water. The thus formed 1,4-dihydropyridines was subsequently oxidized in one-pot to the corresponding pyridine derivatives by either ferric chloride or potassium permanganate.
Multicomponent Domino Cyclization-Oxidative
Aromatization on a Bifunctional Pd/C/K-10
Catalyst: An Environmentally Benign Approach toward the
Synthesis of Pyridines
作者:Béla Török、Omar De Paolis、Jonathan Baffoe、Shainaz Landge
DOI:10.1055/s-0028-1083177
日期:——
A one-pot synthesis of substituted pyridines via a domino cyclization-oxidative aromatization (dehydrogenation) approach is described. The process is based on the use of a new bifunctional noble metal-solid acid catalyst, Pd/C/K-10 montmorillonite and microwave irradiation. The cyclization readily takes place on the strong solid acid while palladium dehydrogenates the dihydropyridine intermediates to the desired products.
Silica-supported ceric ammonium nitrate (CAN): a simple, mild and solid-supported reagent for quickest oxidative aromatization of Hantzsch 1,4-dihydropyridines
An efficient and environmentally benign methodology for the oxidative aromatization of 1,4-dihydropyridines to their corresponding pyridine derivatives is developed. The oxidative aromatization of 1,4-dihydropyridines was explored using silica-supported ceric ammonium nitrate as catalyst in CH3CN with or without sonication at room temperature. This supported catalyst acts as a more efficient oxidising
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