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Advisor(s)
Abstract(s)
Xanthone-1,2,3-triazole dyads have been synthesized by two different approaches, both starting from novel (E)-2-(4-arylbut-1-en-3-yn-1-yl)chromones, prepared through a base-catalyzed aldol reaction of 2-methylchromone and arylpropargyl aldehydes. In the first method, the xanthone moiety is built by Diels-Alder reaction of the referred unsaturated chromones with N-methylmaleimide under microwave irradiation, followed by oxidation of the obtained adducts with DDQ, whereas the 1,2,3-triazole ring results from the cycloaddition reaction of the acetylene moiety with sodium azide. The second strategy first involves the cycloaddition reaction with sodium azide to provide the 1,2,3-triazole ring, followed by methylation of the triazole NH group prior to Diels-Alder reaction with N-methylmaleimide. The last step in this synthesis of novel xanthone-1,2,3-triazole dyads entails oxidation of the cycloadducts with DDQ.
Description
Keywords
Cycloaddition Diels-Alder reaction Cyclization Click chemistry Oxygen heterocycles Nitrogen heterocycles
Citation
Albuquerque, Hélio; Santos, Clementina M.M.; Cavaleiro, José; Silva, Artur (2015). (E)-2-(4-Arylbut-1-en-3-yn-1-yl)chromones as synthons for the synthesis of xanthone-1,2,3-triazole dyads. European Journal of Organic Chemistry. ISSN 1434-193X. 21, p. 4732-4743