Chemo-enzymatic cascades producing 2,5-furandicarboxylic acid precursors via d -gluconate “barbell oxidation” and dehydration

• Published in: Green chemistry : an international journal and green chemistry resource : GC Vol. 25; no. 18; pp. 7126 - 7140
• Main Authors: Chen, Jiao, Cai, Jiali, Sha, Feng, Sun, Wenjun, Lyu, Xilei, Chang, Yonghui, Cao, Fei, Zhao, Lili, Wu, Hongli, Ouyang, Pingkai
• Format: Journal Article
• Language: English
• Published: 18.09.2023
• ISSN: 1463-9262; 1463-9270
• DOI: 10.1039/D3GC01493B

As a potential substitute for petroleum-based terephthalic acid (TPA) in the manufacture of polyesters, 2,5-furandicarboxylic acid has been obtained through several feasible routes. Herein, a new chemo-enzymatic strategy for generating furan-2,5-dicarboxylic acid (FDCA) precursors from sodium gluconate via bio-oxidation and dehydration is presented. By coupling the bio-oxidation of gluconate 5-dehydrogenase with carbonyl reductase PsCR for cofactor regeneration, 5-keto- d -gluconic acid (5KGA), a specific product of d -gluconic acid bio-oxidation and a stable intermediate, was obtained in 99% yield. The statin intermediate ethyl ( S )-4-chloro-3-hydroxybutanoate was simultaneously generated as a co-product via cycling cascade catalysis. Subsequently, the yield of the FDCA precursor n -butyl-5-formyl-2-furancarboxylate ( n Bu-FFCA) generated via 5KGA dehydration and esterification reached 77.9%. Key intermediate characterization and theoretical calculations revealed that the decarboxylation and dehydration of cyclic 5KGA to furfural was the main side-reaction that prevented a better yield of dehydrated 5KGA. This route demonstrates good sustainability and market competitiveness compared to the existing FDCA synthesis methods.