Summary
Ezo spruce (Picea jezoensis) wood meal and milled wood lignin were successively reduced with sodium borohydride, methylated with methanol-HCl, oxidized with Fremy's salt, reduced with sodium dithionite, and methylated with diazomethane. Permanganate oxidation of the treated milled wood lignin showed that 0.08–0.1/C9 units of 3,4,5-trimethoxyphenyl groups were introduced into the softwood lignin. Although hardwood meal (beech, Fagus crenata) methylated with diazomethane gave a purple-red colour with the Mäule test, the treated softwood meal gave only a dark brown colour. The aromatic nuclei of lignin were broken down by the Mäule treatment. The consumption of permanganate by treated softwood lignin was higher than by hardwood lignin, which suggests that the guaiacyl nuclei were broken down severely. It is proposed that the purple-red colour obtained from methylated hardwood lignin with the Mäule colour test is generated by reaction of syringyl groups which were liberated by β-ether cleavage under the permanganate oxidation conditions.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Adler, E.; Lundquist, K. 1961: Estimation of “uncondensed” phenolic units in spruce lignin. Acta Chem. Scand. 15: 223–224
Allen, G. D.; Waters, W. A. 1956: Oxidation of isobutyraldehyde with the free radical from potassium nitrosyldisulfonate. J. Chem. Soc. 1132–1135
Faix, O.; Schweers, W. 1974: Vergleichende Untersuchungen an Polymermodellen des Lignins (DHP's) verschiedener Zusammensetzungen. 3. Mitt. IR-Spektroskopische Untersuchungen. Holzforschung 28: 50–54
Goldschmidt, O. 1954: Determination of the phenolic hydroxyl content of lignin preparations by ultraviolet spectrometry. Anal. Chem. 26: 1421–1423
Iiyama, K.; Nakano, J. 1973: Studies on the color of lignin. X. Effects of chromophoric groups on the color of various lignins. Kami Pa Gikyoshi 27: 530–542
Kawamura, I.; Shinoda, Y.; Nonomura, S. 1974: Comparison of the relative intensities of IR absorption bands of MWL of various woods from tropical and temperate zones. Mokuzai Gakkashi 20: 15–20
Kawamura, I.; Shinoda, Y.; Tran, V. A.; Tanada, T. 1977: Chemical properties of lignin of Erythrina wood. Mokuzai Gakkashi 23: 400–404
Larsson, S.; Miksche, G. E. 1969: Gaschromatographische Analyse von Ligninoxydationsprodukten. II. Nachweis eines neuen Verknüpfungsprinzips von Phenylpropaneeinheiten. Acta Chem. Scand 23: 917–923
Meshitsuka, G.; Nakano, J. 1977: Studies on the mechanism of lignin color reaction XI. Mäule color reaction (7). Mokuzai Gakkaishi 23: 232–236
Meshitsuka, G.; Nakano, J. 1978: Studies on the mechanism of lignin color reaction XII. Mäule color reaction (8). Mokuzai Gakkaishi 24: 563–568
Meshitsuka, G.; Nakano, J. 1979: Studies on the mechanism of lignin color reaction XIII. Mäule color reaction (9). Mokuzai Gakkaishi 25: 588–594
Migita, N.; Nakano, J.; Nagano, T. 1952: Lignin XIV. Mechanism of the Mäule color reaction. Bull. Tokyo Univ. Forests, 43: 145–149
Migita, N.; Nakano, J.; Hashimoto, Y. 1953: Lignin XIV. Mechanism of the Mäule color reaction. Bull. Tokyo Univ. Forests 45: 247–253
Nakano, J.; Hirakawa, K.; Ishizu, A.; Migita, N. 1957: Lignin XXVI. Mechanism of the Mäule color reaction (3). Mokuzai Gakkaishi 3: 23–27
Nakano, J.; Hirakawa, K.; Ishizu, A.; Kobayashi, A.; Migita, N. 1959: Lignin XXXI. Mechanism of the Mäule color reaction (5). Mokuzai Gakkaishi 5: 50–54
Nakano, J.; Migita, N. 1963: Lignin XXXVII. Mechanism of a color reaction of lignin (10). Mäule color reaction. Mokuzai Gakkaishi 9: 62–66
Teuber, H. J.; Staiger, G. 1955: Reactions with nitrosodisulfonate VIII. o-Benzoquinones and phenazines. Chem. Ber. 88: 802–827
Zimmer, H.; Lankin, D. C.; Horgan, S. W. 1971: Oxidations with potassium nitrosodisulfonate (Fremy's radicals). Teuber reaction. Chem. Rev. 71: 229–246
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Iiyama, K., Pant, R. The mechanism of the Mäule colour reaction introduction of methylated syringyl nuclei into softwood lignin. Wood Sci.Technol. 22, 167–175 (1988). https://doi.org/10.1007/BF00355852
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00355852