Incorporation of catechyl monomers into lignins: lignification from the non-phenolic end <i>via</i> Diels–Alder cycloaddition?
نویسندگان
چکیده
Catechyl monomers 1-electron-oxidize and undergo radical coupling to produce benzodioxane units in lignin. Derived o -quinones Diels–Alder reactions giving oxatricyclo new products, but does this occur lignification?.
منابع مشابه
Incorporation of hydroxycinnamaldehydes and hydroxybenzaldehydes into lignins
Hoon Kim, a,b John Ralph,* a,b Fachuang Lu, a,b Sally A. Ralph, c Alain-M. Boudett, d John J. MacKay, e Ronald R. Sederoff, f Takashi Ito, g Shingo Kawai, g Hideo Ohashi g and Takayoshi Higuchi h a US Dairy Forage Research Center, USDA Agricultural Research Service, Madison WI 53706. USA b Department of Forestry, University of Wisconsin, Madison, WI 53706-1598, USA c US Forest Product Laborator...
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NMR analysis of lignins in CAD-deficient plants. Part 1. Incorporation of hydroxycinnamaldehydes and hydroxybenzaldehydes into lignins.
Peroxidase/H2O2-mediated radical coupling of 4-hydroxycinnamaldehydes produces 8-O-4-, 8-5-, and 8-8-coupled dehydrodimers as has been documented earlier, as well as the 5-5-coupled dehydrodimer. The 8-5-dehydrodimer is however produced kinetically in its cyclic phenylcoumaran form at neutral pH. Synthetic polymers produced from mixtures of hydroxycinnamaldehydes and normal monolignols provide ...
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ژورنال
عنوان ژورنال: Green Chemistry
سال: 2021
ISSN: ['1463-9262', '1463-9270']
DOI: https://doi.org/10.1039/d1gc03022a