Catalytic coupling of biomass-derived aldehydes into intermediates for biofuels and materials†
Abstract
Biomass-based aldehydes, especially the sugar-derived furfural (FF), 5-hydroxymethylfurfural (HMF), and lignin-derived vanillin, are abundant and renewable, but their downstream applications often require further catalytic upgrading into chain-extended intermediates for the production of useful biofuels and renewable materials. This review article focuses on the catalytic upgrading processes that involve C–C bond forming, chain-extension coupling reactions of FF, HMF, and vanillin, as well as subsequent transformations of the resulting intermediates into value-added biofuels and polymeric materials. The topics are organized according to the three major types of the catalysts commonly employed for such upgrading and transformations: organic catalysts, metal-based catalysts, and recyclable supported catalysts.