Radical-initiated oxygenation of flavonols by dioxygen

Research output: Contribution to journalArticle

19 Citations (Scopus)

Abstract

In the presence of free radicals, such as 2,2,6,6-tetramethyl-1-piperidinyloxyl (TEMPO) and 2,6-di-tert-butyl-a-(3,5-di-tert-butyl-4-oxo-2,5-cyclohexadien-1-ylidene)- p-tolyloxyl (galvinoxyl), flavonols undergo catalytic oxygenation to the corresponding depsides (phenolic carboxylic acid esters), with concomitant evolution of CO. The oxygenolysis was performed in aprotic solvents (DMF, MeCN) and was followed by Glc. The results of oxygenation of 4′-substituted flavonols show that the formation of flavonoxy species is the key step in the activation process of the substrate, and that electron-releasing substituents enhance the reaction rate.

Original languageEnglish
Pages (from-to)33-36
Number of pages4
JournalJournal of Molecular Catalysis A: Chemical
Volume171
Issue number1-2
DOIs
Publication statusPublished - Jun 12 2001

Fingerprint

Flavonols
Oxygenation
oxygenation
Depsides
Oxygen
releasing
Carbon Monoxide
Carboxylic Acids
Free radicals
Carboxylic acids
carboxylic acids
free radicals
Reaction rates
Free Radicals
esters
Esters
reaction kinetics
Chemical activation
activation
Electrons

Keywords

  • Dioxygenase model
  • Flavonol oxidation
  • Galvinoxyl
  • Quercetinase
  • TEMPO

ASJC Scopus subject areas

  • Catalysis
  • Process Chemistry and Technology

Cite this

Radical-initiated oxygenation of flavonols by dioxygen. / Kaizer, J.; Speier, G.

In: Journal of Molecular Catalysis A: Chemical, Vol. 171, No. 1-2, 12.06.2001, p. 33-36.

Research output: Contribution to journalArticle

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