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Cobalt-Catalyzed Oxidation of the ?-O-4 Bond in Lignin and Lignin Model Compounds.

ABSTRACT: In this work we demonstrate the use of Co(acac)3 in combination with N-hydroxyphthalimide as an oxidant for the selective ?-oxidation of the representative ?-O-4 linkages in lignin model compounds. The oxidation reaction proceeds under mild conditions at 80 °C using 1,4-dioxane as the solvent and an oxygen atmosphere. The prior ?-oxidation in the ?-O-4 linkage of the lignin polymer is known to result in an easier cleavage of the adjacent C-O and C-C bonds because of a decrease in bond stability. Finally, the conditions were successfully transferred to kraft- and organosolv-lignin samples as proven by 2D-NMR (HSQC) experiments and gel permeation chromatography measurements.

SUBMITTER: Rinesch T

PROVIDER: S-EPMC6644884 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Cobalt-Catalyzed Oxidation of the β-O-4 Bond in Lignin and Lignin Model Compounds.

Rinesch Torsten T Bolm Carsten C

ACS omega 20180730 7

In this work we demonstrate the use of Co(acac)<sub>3</sub> in combination with <i>N</i>-hydroxyphthalimide as an oxidant for the selective α-oxidation of the representative β-O-4 linkages in lignin model compounds. The oxidation reaction proceeds under mild conditions at 80 °C using 1,4-dioxane as the solvent and an oxygen atmosphere. The prior α-oxidation in the β-O-4 linkage of the lignin polymer is known to result in an easier cleavage of the adjacent C-O and C-C bonds because of a decrease ...[more]

PMID: 31458968

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