Synthesis of functionalized benzimidazoles and quinoxalines catalyzed by sodium hexafluorophosphate bound Amberlite resin in aqueous medium
作者:Pranab Ghosh、Amitava Mandal
DOI:10.1016/j.tetlet.2012.09.045
日期:2012.11
for the selective synthesis of 1,2-disubstitutedbenzimidazoles and quinoxalines in water–methanol (1:1) mixture with the aid of resin bound hexafluorophosphate ion as catalyst is reported. The method is also effective for the incorporation of quinoxaline nucleus at the A ring of pentacyclic triterpenoid, friedelin. A plausible mechanism for the formation of disubstituted benzimidazole has also been suggested
iodine-mediated oxidative annulation of aryl acetylenes-arylethenes-aromatic ketones with 1,2-diamines for the synthesis of pyrazines and regioselective synthesis of quinoxalines is presented. A multipathway coupled domino approach has been developed for the one-pot synthesis of 1,4-diazines with high functional group compatibility.
Synthesis of libraries of quinoxalines through eco-friendly tandem oxidation–condensation or condensation reactions
作者:Susmita Paul、Basudeb Basu
DOI:10.1016/j.tetlet.2011.09.141
日期:2011.12
A facile and expeditious solid-phase synthesis of libraries of quinoxalines promoted on KF-alumina surface via tandem oxidation–condensation or condensation reactions is reported. The reaction protocol is operationally simple and mild. Moreover, solvent-free reaction condition makes the reaction procedure eco-friendly and economically viable.
Elemental Sulfur-Mediated Synthesis of Quinoxalines from Sulfoxonium Ylides
作者:Trayambek Nath Chaubey、Paran J. Borpatra、Satyendra Kumar Pandey
DOI:10.1021/acs.orglett.3c01907
日期:2023.7.21
A novel straightforward and catalyst-free approach for synthesizing quinoxaline derivativesfrom sulfoxonium ylides and o-phenylenediamines mediated by elemental sulfur has been described. Due to the simple and mild reaction conditions, the sulfoxonium ylides and o-phenylenediamines decorated with different functional groups furnished moderate to high yields of quinoxaline derivatives and were well
γ-Maghemite-silica nanocomposite: A green catalyst for diverse aromatic N-heterocycles
作者:Pranab Ghosh、Amitava Mandal、Raju Subba
DOI:10.1016/j.catcom.2013.06.026
日期:2013.11
gamma-Maghemite-silica nanocomposite has been applied as a green catalyst to synthesize variety of aromatic N-heterocycles under solvent free conditions. Characterization was done by modern analytical tools (UV, IR, AAS, DSC, EDXRF, powdered XRD, EPR, Mossbauer and TEM). Mild reaction conditions and recyclability have made the present protocol both environmentally and economically viable. (c) 2013 Elsevier B.V. All rights reserved.