CO₂-Mediated Conversion of Furfuryl Alcohol to 4-Hydroxycyclopentanone and its Toxicological Assessment

Abstract

Through a combined chemical-toxicological study, this report re-explores the Piancatelli rearrangement of furfuryl alcohol into 4-hydroxycyclopentenone (4-HCP), a key building block for the synthesis of bio-based solvents. In this context, we demonstrate that (1) in aqueous media, the addition of CO₂ results in a fivefold increase in the rate of the Piancatelli rearrangement of furfuryl alcohol to 4-HCP, even at temperatures as low as 120 °C, and (2) 4-HCP exhibits pronounced cyto- and genotoxicity, approximately 200 times higher than that of furfural. Based on these results, we recommend avoiding the isolation of 4-HCP and instead converting it in situ into cyclopentanone or cyclopentanol, two identified safer downstream target chemicals through toxicological studies.