Catalytic Oxidation of Methoxy Substituted Benzyl Alcohols as Model for Lignin Derivatives Valorisation

Lignin moieties consist in three hydroxycinnamyl alcohol derivatives (monolignols), p-coumaryl, coniferyl and sinapyl alcohols, which differ in the degree of methoxylation on the aromatic ring [1]. Their oxidation to aldehydes or acids is one of the major methods for their valorisation [2]. Au-Pd based catalysts proved to be active for the benzyl alcohol (BA) oxidation [3]. Moreover, Wang et al. [4] showed that the Au:Pd ratio on the surface of the particles is a key parameter that influences the catalytic performance. On the basis of these results, here we investigated the effect of the methoxy substituent on catalytic activity of carbon supported Au-Pd catalysts by studying the oxidation of 4- and 3,4-Dimethoxybenzyl alcohol (4-MBA, 3,4-DMBA) to the corresponding aldehydes.