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Journal of Wood Science

Official Journal of the Japan Wood Research Society

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Solvent effects on the electronic state of monolignol radicals as predicted by molecular orbital calculations

Journal of Wood Science volume 54, pages 308–311 (2008)Cite this article

Abstract

The spin and charge densities in three monolignol radicals were computed using the UB3LYP/6-31G* method of molecular orbital calculation. As well, the effects of solvents were simulated by using an SCI-PCM model. It was confirmed that an unpaired electron was localized at C1, C3, C5, C8, and O4 for all monolignol radicals. In solvents, the spin density decreased at O4 with increasing solvent polarity, but increased at C8. The atomic charges at all reactive atoms had a negative value and were obviously strengthened at O4 with increasing solvent polarity. These tendencies support the experimental results for radical coupling reactions of monolignols in various solvents; that is, that 8-O4′ linkages are produced much more often than 8-8′ linkages in nonpolar solvents.

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Authors and Affiliations

  1. Faculty of Engineering, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka, 814-0180, Japan

    Mikiji Shigematsu & Hiroshi Masamoto

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  1. Mikiji Shigematsu
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  2. Hiroshi Masamoto
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Correspondence to Mikiji Shigematsu.

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Shigematsu, M., Masamoto, H. Solvent effects on the electronic state of monolignol radicals as predicted by molecular orbital calculations. J Wood Sci 54, 308–311 (2008). https://doi.org/10.1007/s10086-008-0955-7

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  • DOI: https://doi.org/10.1007/s10086-008-0955-7

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