Synthesis of beta-O-4-type artificial lignin polymers and their analysis by NMR spectroscopy.
We describe the synthesis and NMR spectroscopic analysis of three artificial lignin polymers containing only the beta-O-4 substructure: syringyl-type homopolymer, p-hydroxyphenyl-type homopolymer and guaiacyl/syringyl-type heteropolymer. Using gel permeation chromatography, the weight-average degree of polymerization (DP(w)) of the three polymers was determined as 19.2, 38.6, and 13.9, respectively. The polymers were prepared based on the synthetic methodology of guaiacyl-type homopolymer, and were fully characterized using (1)H-, (13)C-, and (1)H-(13)C NMR spectroscopy of the acetylated and non-acetylated forms. The spectra of guaiacyl/syringyl-type heteropolymers were in good agreement with those of the beta-O-4 substructure of milled wood lignin obtained from the hardwood of Japanese white birch.
Kishimoto
Takao
T
Laboratory of Wood Chemistry, Research Group of Bioorganic Chemistry, Division of Applied Bioscience, Research Faculty of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan. takao@pu-toyama.ac.jp
Uraki
Yasumitsu
Y
Ubukata
Makoto
M
D002850:Chromatography, Gel; D008031:Lignin / Q000138:chemical synthesis* / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010100:Oxygen / Q000737:chemistry*; D010626:Phenylethyl Alcohol / Q000031:analogs & derivatives / Q000737:chemistry
C434470:guaiacyl monolignol; C434469:syringyl monolignol; C043584:2-hydroxyphenylethanol; D008031:Lignin; D010626:Phenylethyl Alcohol; D010100:Oxygen