کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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4562339 | 1330711 | 2008 | 4 صفحه PDF | دانلود رایگان |
4-Hydroxycinnamic, 4-methoxycinnamic, ferulic and cinnamic acids were both non-oxidatively and oxidatively decarboxylated in alkaline aqueous media in the presence of l-cysteine–Fe(II) and l-cysteine–Co(II) heterogeneous catalysts using hydrogen peroxide or molecular oxygen. GC/MS analysis of diethylether extracts of reaction mixtures confirmed that the addition of hydrogen peroxide resulted predominantly in oxidative decarboxylation of substituted cinnamic acids, producing the corresponding carbonyl compounds (4-hydroxybenzaldehyde, 4-methoxybenzaldehyde, vanillin, benzaldehyde). On the other hand, saturation of this heterogeneous reaction system with molecular oxygen led to the formation of a variety of products, probably via peroxoacid anions or peroxoradical intermediates, e.g., ferulic acid was transformed to vinylguaiacol and vanillin with yields of 22% and 0.7%, respectively.
Journal: Food Research International - Volume 41, Issue 4, 2008, Pages 429–432