Computational electrochemistry of lignin model compounds

摘要

The redox potential of lignin is of critical importance for a number of processes, including its polymerization, degradation by fungi and bleaching of pulps. The experimental measurement of this parameter can, however, be problematic. Since the oxidation reactions are not reversible, the use of relatively simple cyclic voltammetry is not appropriate. As a consequence, the more complex pulse radiolytic techniques have been reported in the literature for several groups of phenolic compounds. The recent literature indicates that single-electron, aqueous redox potentials may be accurately calculated using current methods in computational chemistry and a thermodynamic cycle. In the current paper, density functional calculations (B3LYP/6-31G(d)) have performed on phenolic compounds for which experimental redox potentials are available, with excellent agreement. This work is extended to monolignols and dilignols.