The Achmatowicz rearrangement enables the oxidative ring expansion of furfuryl alcohols into dihydropyranones, key motifs in natural products. Herein, we report a mild, metal-free method using a HBr-H2O2 system as an inexpensive source of electrophilic bromine species. The optimized conditions accommodate a broad range of primary, secondary, and tertiary furfuryl alcohols, providing a practical approach to access structurally diverse pyranone scaffolds.
Sun et al. (Thu,) studied this question.