z-logo
Premium
Identifying the Interunit Linkages Connecting Free Phenolic Terminal Units in Lignin
Author(s) -
Saito Kaori,
Makimura Yutaka,
Nishimura Hiroshi,
Watanabe Takashi
Publication year - 2021
Publication title -
chemsuschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.412
H-Index - 157
eISSN - 1864-564X
pISSN - 1864-5631
DOI - 10.1002/cssc.202100180
Subject(s) - lignin , monomer , chemistry , polymerization , polymer , phenols , linkage (software) , polymer chemistry , organic chemistry , stereochemistry , biochemistry , gene
Understanding the linkages connecting phenolic terminal and nonphenolic units in complex branched polymer, lignin, is crucial to facilitate efficient and selective valorization of lignin. In this study, the interunit linkages connecting phenolic units are identified by premethylation of the phenolic hydroxy groups and thioacidolysis‐desulfuration. Interestingly, the phenolic units are found to be connected by only β‐5, β‐1, and β‐O‐4 linkages. The phenolic unit abundance is approximately 20 %. The result reveals that lignin polymerization terminates with the three linkages by a coupling between a monomer and the polymer terminus, which is reasonably explained by the radical coupling mechanism. Unexpectedly, 5‐5, 4‐O‐5, and β–β linkages connecting the phenolic units are not detected, indicating that these units are further elongated to form nonphenolic units. This study reveals the linkage types connecting phenolic and nonphenolic units and their elongation mechanisms.

This content is not available in your region!

Continue researching here.

Having issues? You can contact us here