Regioselectivity of Enzymatic and Photochemical Single Electron Transfer Promoted Carbon−Carbon Bond Fragmentation Reactions of Tetrameric Lignin Model Compounds

2011 ◽  
Vol 76 (8) ◽  
pp. 2840-2852 ◽  
Author(s):  
Dae Won Cho ◽  
John A. Latham ◽  
Hea Jung Park ◽  
Ung Chan Yoon ◽  
Paul Langan ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Single Electron ◽  
Single Electron Transfer ◽  
Model Compounds ◽  
Lignin Model Compounds ◽  
Carbon Bond ◽  
Carbon Carbon Bond ◽  
Lignin Model ◽  
Fragmentation Reactions

Nature and Kinetic Analysis of Carbon−Carbon Bond Fragmentation Reactions of Cation Radicals Derived from SET-Oxidation of Lignin Model Compounds

2010 ◽  
Vol 75 (19) ◽  
pp. 6549-6562 ◽  
Author(s):  
Dae Won Cho ◽  
Ramakrishnan Parthasarathi ◽  
Adam S. Pimentel ◽  
Gabriel D. Maestas ◽  
Hea Jung Park ◽  
...  
Keyword(s):  
Kinetic Analysis ◽  
Model Compounds ◽  
Lignin Model Compounds ◽  
Carbon Bond ◽  
Cation Radicals ◽  
Carbon Carbon Bond ◽  
Lignin Model ◽  
Fragmentation Reactions

scholarly journals Exploiting single-electron transfer in Lewis pairs for catalytic bond-forming reactions

2020 ◽  
Vol 11 (17) ◽  
pp. 4305-4311 ◽  
Author(s):  
Yoshitaka Aramaki ◽  
Naoki Imaizumi ◽  
Mao Hotta ◽  
Jun Kumagai ◽  
Takashi Ooi
Keyword(s):  
Electron Transfer ◽  
Bond Formation ◽  
Ion Pair ◽  
Single Electron ◽  
Single Electron Transfer ◽  
Carbon Bond ◽  
Bond Forming ◽  
Carbon Carbon Bond ◽  
Pair Generation ◽  
Lewis Pairs

Radical–ion pair generation from common Lewis pairs and its application to catalytic carbon–carbon bond formation.

Studies on electrooxidation of lignin and lignin model compounds. Part 1: Direct electrooxidation of non-phenolic lignin model compounds

Holzforschung ◽  
2012 ◽  
Vol 66 (3) ◽  
Author(s):  
Takumi Shiraishi ◽  
Toshiyuki Takano ◽  
Hiroshi Kamitakahara ◽  
Fumiaki Nakatsubo
Keyword(s):  
Electron Transfer ◽  
Cyclic Voltammetry ◽  
Carbonyl Compounds ◽  
Model Compounds ◽  
Lignin Model Compounds ◽  
Bulk Electrolysis ◽  
Lignin Model ◽  
Dimeric Compound ◽  
High Yields ◽  
Short Time

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.

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