Hardwood lignin in eucalyptus was first converted to hardwood lignocresol through a phase separation process utilizing wood meal, sulfuric acid, and p-cresol at ambient temperature. A syringyl methyl benzofuran, S2 was selectively obtained via a syringyl-type phenolic dimer with a coumaran ring, S1 by NaOH treatments of hardwood lignocresol at 170 °C. Our process controls the reactivity of Cα linkages, Cβ-aryl-ethers, and Cγ-OH in sequence, successfully resulting in a high yield of specific aromatic chemicals from hardwood lignin based on the successiveness of Cβ-aryl-ethers between syringyl units.
- Hiroshi Nonaka
- Ryota Yamamoto
- Masamitsu Funaoka
