Study of the oxidative esterification of furfural catalyzed by Au25(glutathione)18 nanocluster deposited on zirconia

[Display omitted] •Au25(SG)18/ZrO2 nanoclusters were used in the furfural oxidative esterification.•The influence of calcination temperature was demonstrated.•Quantitative formation of methyl-2-furoate was obtained with high initial activities. Au/ZrO2 catalyst prepared from Au25(SG)18 nanoclusters (SG stands for glutathione) deposited on ZrO2 has shown to be an efficient system for the oxidative esterification of furfural with methanol. The influence of the supported nanoclusters was studied and showed that partial calcination of the supported nanoclusters at 300 °C was sufficient for a quantitative formation of methyl-2-furoate even in the absence of a base. In the presence of 0.27 mol% of Au, initial activities up to 250 h−1 were obtained at 100 °C under 6 bar of O2. The reactivity was extended to the oxidative esterification of furfuryl alcohol and the formation of various products and intermediates was discussed.