The reaction of a series of cis-fused bicyclic β-hydroxytetrahydrofurans with ruthenium tetraoxide, generated in situ from ruthenium trichloride and sodium periodate, afforded 9- and 10-membered keto-lactones in moderate to good yields, in a clean and straightforward fashion. The starting β-hydroxyethers were obtained from the corresponding 3-alkenols by two alternative procedures, depending on their pattern of substitution:(a) epoxidation by ...
