Synthesis of triazole-fused tetracyclic glycosides in aqueous medium: application of nanodomain cubic cuprous oxide as reusable catalyst in one-pot domino Sonogashira-cyclization
摘要:
An environmentally benign one-pot procedure has been developed for the syntheses of triazole-fused tetracyclic glycosides in aqueous medium. The two step one-pot synthesis involves Sonogashira reaction between azido-alkynes and aryl halides followed by intramolecular 1,3-dipolar cyclization using cubic cuprous oxide nanoparticles as reusable catalyst, under aerobic condition. The method excludes the use of any surfactants or additional ligands as stabilizing agents. The catalyst could be used up to three recycles without any loss of catalytic activity. The method has a broad perspective for the synthesis of medium size ring systems. (C) 2015 Elsevier Ltd. All rights reserved.
An approach toward the syntheses of triazolo benzoxazines, triazolo quinoxalines, triazolo benzodiazepines, triazolo benzoxazepines, and triazolo benzothiazines via a simple and convenient protocol using basic alumina as solid support
作者:Nivedita Chatterjee、Swarbhanu Sarkar、Rammyani Pal、Asish Kumar Sen
DOI:10.1016/j.tetlet.2014.02.080
日期:2014.4
A microwave assisted green protocol for the syntheses of triazole fused benzoxazines, benzoxazepines, quinoxalines, and benzothiazines was investigated using basic alumina as solid support. The one-pot reaction was carried out using Cu(phen)(PPh3)Br as a catalyst. The protocol did not require the use of any additional ligands, base or the use of expensive and toxic palladiums. (C) 2014 Elsevier Ltd. All rights reserved.