Supported Pd-catalyzed carbonylative transformation of biomass-derived furfural to 2,5-furandicarboxylic acid

Abstract

Herein, we have developed an unprecedented route for the synthesis of 2,5-furandicarboxylic acid (FDCA), a monomer of the polyethylene furanoate (PEF) polymer, from biomass-derived furfural. The developed protocol exhibits sequential bromination, carbonylative esterification, and oxidative hydrolysis from C-5 based renewable furfural to C-6-based FDCA. First, the unstable furfural was efficiently transformed into 5-bromofuran-2-carbaldehyde using a simple reagent system. Next, the developed polystyrene-supported palladium (Pd@PS) nanoparticles (NPs) catalyzed carbonylative esterification of 5-bromofuran-2-carbaldehyde to various alkyl 5-formylfuran-2-carboxylates using oxalic acid as CO source and alcohols as a nucleophile is the key step associated in the present methodology. Additionally, Pd@PS NPs efficiently catalyzed the oxidative hydrolysis of alkyl 5-formylfuran-2-carboxylates to FDCA in good yields under mild reaction conditions.