Studies on electrooxidation of lignin and lignin model compounds. Part 1: Direct electrooxidation of non-phenolic lignin model compounds
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Takumi Shiraishi
,
Toshiyuki Takano
Abstract
The direct anodic oxidation of non-phenolic lignin model compounds was investigated to understand their basic behaviors. The results of cyclic voltammetry (CV) studies of monomeric model, such as 1-(4-ethoxy-3-methoxyphenyl)ethanol, are interpreted as the oxidation for Cα-carbonylation did not proceed in the reaction without a catalyst, but a base promotes this reaction. Indeed, the bulk electrolyses of the monomeric lignin model compounds with 2,6-lutidine afforded the corresponding Cα-carbonyl compounds in high yields (60–80%). It is suggested that deprotonation at Cα-H in the ECEC mechanism (E=electron transfer and C=chemical step) is important for Cα-carbonylation. In the uncatalyzed bulk electrolysis of a β-O-4 model dimeric compound, 4-ethoxy-3-methoxyphenylglycerol-β-guaiacyl ether, the corresponding Cα-carbonyl compound was not detected but as a result of Cα-Cβcleavage 4-O-ethylvanillin was found in 40% yield. In the electrolysis reaction in the presence of 2,6-lutidine (as a sterically hindered light base), the reaction stopped for a short time unexpectedly. These results indicate the different electrochemical behavior of simple monomeric model compounds and dimeric β-O-4 models. The conclusion is that direct electrooxidation is unsuitable for Cα-carbonylation of lignin.
©2012 by Walter de Gruyter Berlin Boston
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- Characterization of MWLs from Tamarix ramosissima isolated before and after hydrothermal treatment by spectroscopical and wet chemical methods
- Studies on electrooxidation of lignin and lignin model compounds. Part 1: Direct electrooxidation of non-phenolic lignin model compounds
- Studies on electro-oxidation of lignin and lignin model compounds. Part 2: N-Hydroxyphthalimide (NHPI)-mediated indirect electro-oxidation of non-phenolic lignin model compounds
- Shaped hemocompatible aerogels from cellulose phosphates: preparation and properties
- The effects of combining guaiacol and syringol on their pyrolysis
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- Evidence that release of internal stress contributes to drying strains of wood
- Structure of oak wood from the Swedish warship Vasa revealed by X-ray scattering and microtomography
- Physical properties of simul (red-silk cotton) wood (Bombax ceiba L.) chemically modified with styrene acrylonitrile co-polymer and nanoclay
- Characterisation of moisture-dependent plasticity of beech wood and its application to a multi-surface plasticity model
- Vibration method for grading of large cross-section coniferous timber species
- Ultrastructural evaluation of compression wood-like properties of common juniper (Juniperus communis L.)
- Effect of ammonia addition to alkaline copper quaternary wood preservative solution on the distribution of copper complexes and leaching
- Morphological responses of Betula protoplasts in fiber spinning
- Erratum
- Surface chemistry of vessel elements by FE-SEM, μ-XPS and ToF-SIMS
- Meetings
- Meetings
- Masthead
- 10.1515/hf-2012-masthead3
Articles in the same Issue
- Original Papers
- Refiner bleaching in a peroxide-based ATMP process compared with conventional bleaching
- Chemical characterization of polymerized products formed in the reactions of matairesinol and pinoresinol with the stable radical 2,2-diphenyl-1-picrylhydrazyl
- Characterization of MWLs from Tamarix ramosissima isolated before and after hydrothermal treatment by spectroscopical and wet chemical methods
- Studies on electrooxidation of lignin and lignin model compounds. Part 1: Direct electrooxidation of non-phenolic lignin model compounds
- Studies on electro-oxidation of lignin and lignin model compounds. Part 2: N-Hydroxyphthalimide (NHPI)-mediated indirect electro-oxidation of non-phenolic lignin model compounds
- Shaped hemocompatible aerogels from cellulose phosphates: preparation and properties
- The effects of combining guaiacol and syringol on their pyrolysis
- Multi-steps degradation method for β-O-4 linkage in lignins: γ-TTSA method. Part 1: Reaction of non-phenolic dimeric β-O-4 model compounds
- Optimization of Burkholderia sp. ZYB002 lipase production for pitch control in thermomechanical pulping (TMP) processes
- Evidence that release of internal stress contributes to drying strains of wood
- Structure of oak wood from the Swedish warship Vasa revealed by X-ray scattering and microtomography
- Physical properties of simul (red-silk cotton) wood (Bombax ceiba L.) chemically modified with styrene acrylonitrile co-polymer and nanoclay
- Characterisation of moisture-dependent plasticity of beech wood and its application to a multi-surface plasticity model
- Vibration method for grading of large cross-section coniferous timber species
- Ultrastructural evaluation of compression wood-like properties of common juniper (Juniperus communis L.)
- Effect of ammonia addition to alkaline copper quaternary wood preservative solution on the distribution of copper complexes and leaching
- Morphological responses of Betula protoplasts in fiber spinning
- Erratum
- Surface chemistry of vessel elements by FE-SEM, μ-XPS and ToF-SIMS
- Meetings
- Meetings
- Masthead
- 10.1515/hf-2012-masthead3
