AgSbF 6 -Promoted Divergent Synthesis of 5-(Acetoxymethyl)furfural and 2-Acetoxypyran-3-one from 2-Acetoxy Glycals

We report an efficient and selective AgSbF 6 -catalyzed protocol for the synthesis of 5-(acetoxymethyl)furfural (AcMF) and its structurally diverse derivatives from readily accessible 2acetoxy glycals. The Lewis acidic nature of AgSbF 6 enables rapid glycal activation and promotes a controlled rearrangement dehydration sequence, affording functionalized furfurals in good yields. Notably, AcMF exhibits improved physicochemical properties compared to 5hydroxymethylfurfural due to its less hydrophilic acetoxymethyl group. Interestingly, variation of the glycals, particularly in 2-acetoxy arabinals, leads to the formation of an unexpected product, 2-acetoxypyran-3-one. Furthermore, AcMF can be readily converted into HMF, underscoring its synthetic versatility. Overall, this methodology offers a practical approach for accessing furfuralbased platform molecules of relevance in medicinal chemistry and biomass valorization.