Studies on Lignin Model Compounds of the beta-O-4 Type: Crystal Structures of threo-1-(4-Hydroxy-3,5-dimethoxyphenyl)-2-(2-methoxyphenoxy)-1,3-propanediol and 3-Hydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-2-(2-methoxyphenoxy)-1-propanone--Methanol (1/1).

Publisher Website
Google Scholar
Abstract
Structural elements of the .beta.-O-4 type in lignins can be divided into three categories: arylglycerol .beta.-aryl ethers (I), derivatized arylglycerol .beta.-aryl ethers (II) and remaining structures of the .beta.-O-4 (III), e.g. 2-aryloxypropiophenones (IIIa). Within these categories there are structural variations arising from the nature of the aromatic groups and the stereochemistry. The crystal structures of a lignin model of category I type [threo-1-(4-hydroxy-3,5-dimethoxyphenyl)-2-(2-methoxyphenoxy)-1,3-propanediol (1)] and of the methanol solvate of a lignin model of category III type [3-hydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-2-(2-methoxyphenoxy)-1-propanone (2)] have been determined from single-crystal X-ray diffraction data. Compound 1 crystallizes in space group P.hivin.1 with a = 7.220 (3), b = 10.747(7), c = 12.045(6) .ANG., .alpha. = 109.41(4), .beta. = 90.57 (4), .gamma. = 103.28(4).degree. and Z = 2. Full-matrixleast-squares refinement of 314 structuralparameters gave R = 0.052 for 2208 observed [I > 3.sigma.(I)] reflexions. The methanol solvate of compound 2 crystallizes in space group Pca21 with a = 27.534(14), b = 5.139(2), c = 12.868(5) .ANG. and Z = 4. Full-matrix least-squares refinement of 339 structural parameters gave R = 0.042 for 1092 observed [I > 3.sigma.(I)] reflexions.

This publication has 0 references indexed in Scilit: