Inorganic metal (hydro)oxide supports with appropriate basicity or acid-base properties can promote oxidative esterification of furfural over Au-based catalysts, however, they suffer the problems of easy inactivation induced by the leaching of the components in this water-producing reaction and the shield of catalytic sites by product adsorption. In this work, we report efficient and stable oxidative esterification of furfural over Au nanoparticles anchored in aminopropyl-grafted silica aerogel. The support is insoluble and possesses no strong Lewis acid sites to adsorb oxygen-containing products or intermediates, reducing the probability of catalyst deactivation induced by adsorption. In 7 cycles of reactions, the catalyst maintained the initial activity without any treatments, the yields of alkyl furoate kept above 98 %, and no agglomeration and leaching of Au occurred. Moreover, the roles of Au, alkyl chain, À NH 2 group and Au-activated O species in reactions were clarified, and accordingly, a possible catalytic mechanism involving oxidative dehydrogenation was given.

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