Abstract Hydrolysis of allyl carbinol oxides in aqueous HClO 4 gave the corresponding 1, 2, 4-triols. On heating in the same reaction medium, they underwent cyclization into 3- hydroxytetrahydrofurans. The method is restricted to substrates that can generate stable carbocations via elimination of the hydroxy group from position 4 in intermediate 1, 2, 4- triols.
