The Structure and Conformation of Lignin as Judged by X-ray Crystallographic Investigations of Lignin Model Compounds: Arylglycerol β-Syringyl Ethers
Paper in proceedings, 2008
Structural elements of the arylglycerol β-syringyl ether type are very frequent in hardwood lignins. A variety of crystalline dimeric lignin models representing different diastereomeric forms of structural elements in lignin of
this type have been studied using X-ray crystallography. Bond distances and bond angles in the model
compounds are in all probability nearly identical with those of the corresponding structural elements in lignins.
Based on X-ray crystallographic data from four compounds a sequence of units (5 aromatic rings, 8 chiral Catoms)
attached to each other by β-syringyl ether linkages was constructed. The appearance of the resulting
oligomer illustrates that stereoisomerism can be expected to influence the shape of the lignin molecules to a great
extent. The constructed oligomer constitutes one of 256 possible stereoisomers (128 racemates).