Integration of Chemical and Biological Catalysis: Production of Furylglycolic Acid from Glucose via Cortalcerone

Furylglycolic acid (FA), a pseudoaromatic hydroxy-acid suitable for copolymerization with lactic acid, can be produced from glucose via enzymatically derived cortalcerone using a combination of Brønsted and Lewis acid catalysts. Cortalcerone is first converted to furylglyoxal hydrate (FH) over a Brønsted acid site (HCl or Al-containing betazeolite), and FH is subsequently converted to FA over a Lewis acid site (Sn-beta zeolite). Selectivity for conversion of FH to FA is as high as 80% at 12% conversion using tetrahydrofuran (THF) as a solvent at 358 K. Higher conversion of FH leads to FA-catalyzed degradation of FH and subsequent deactivation of the catalyst by the deposition of carbonaceous residues. The deactivated catalyst can be regenerated by calcination. Cortalcerone can be produced from 10% glucose solution using recombinant Escherichia coli strains expressing pyranose 2-oxidase and aldos-2-ulose dehydratase from the wood-decay fungus Phanerochaete chrysosporium BKM-F-1767. This enzymatically derived cortalcerone is converted in one pot to FA in a methanol/water solvent over an Al-containing Sn-beta zeolite possessing both Brønsted and Lewis acid sites, achieving 42% selectivity to FA at 53% cortalcerone conversion.