论文信息 - Delignification Mechanism during High-Boiling Solvent Pulping. Part 2. Homolysis of Guaiacylglycerol-β-Guaiacyl Ether

Delignification Mechanism during High-Boiling Solvent Pulping. Part 2. Homolysis of Guaiacylglycerol-β-Guaiacyl Ether

Summary A phenolic β-O-4 type lignin model compound, guaiacylglycerol-β-guaiacyl ether, was treated with 70 wt % aq 1,4-butanediol solution at 180°C to investigate the delignification mechanism under high-boiling solvent (HBS) pulping conditions. Thirteen compounds including four monomers, six dimers, two trimers and a tetramer were isolated from the reaction products. Most of these products were generated by recombination of phenoxy radicals formed by homolysis of the β-aryl ether. The results suggest that phenolic β-O-4 linkages in lignin are cleaved homolytically (radical mechanism) via quinone methide intermediates under HBS pulping conditions.

T. Kishimoto | Y. Sano

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