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Long-Lasting Antioxidant Protection: A Regenerable BHA Analogue.
- Source :
-
Journal of Organic Chemistry . 11/19/2010, Vol. 75 Issue 22, p7535-7541. 41p. 6 Diagrams, 2 Charts, 4 Graphs. - Publication Year :
- 2010
-
Abstract
- Introduction of an octyltelluro group ortho to the phenolic moiety in 3-tert-butyl-4-hydroxyanisole (BHA) was found to significantly improve the antioxidant characteristics of the material. In contrast to BHA and the corresponding ortho-substituted octylthio- (9c) and octylseleno (9b) derivatives, the organotellurium 9a was regenerable when assayed for its capacity to inhibit azo-initiated peroxidation of linoleic acid in a chlorobenzene/water two-phase system containing N-acetylcysteine as a stoichiometric reducing agent, and peroxyl radicals were quenched more efficiently than with α-tocopherol. In the homogeneous phase, inhibition of styrene autoxidation occurred with a rate constant kinh as large as 1 x 107 M-1 s-1 but with a low (n = 0.4) stoichiometric factor. Evans- Polanij plots of log (kinh) versus BDE(O-H), which are usually linear for phenols with similar steric crowding reacting by H-atom transfer, revealed that compound 9a was more than 2 orders of magnitude more reactive than expected. Although further mechanistic investigations are needed, it seems that the ortho-arrangement of an alkyltelluro group and hydroxyl should be considered a privileged structure for phenolic antioxidants. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 00223263
- Volume :
- 75
- Issue :
- 22
- Database :
- Academic Search Index
- Journal :
- Journal of Organic Chemistry
- Publication Type :
- Academic Journal
- Accession number :
- 56916429
- Full Text :
- https://doi.org/10.1021/jo101239c