Selective ruthenium-catalyzed oxidation of 1,2:4,5-di-O-isopropylidene- beta-D-fructopyranose and other alcohols with NaOCl.

[reaction: see text] The asymmetric epoxidation catalyst 1,2:4,5-di-O-isopropylidene-beta-D-erythro-2,3-hexadiulo-2,6-pyranose 2 was obtained in high yield from 1,2:4,5-di-O-isopropylidene-beta-D-fructopyranose 1 via a recyclable ruthenium-catalyzed hypochlorite oxidation protocol under biphasic conditions (MTBE/water) in the presence of an alkaline buffer (pH 9.5). Other secondary alcohols were also oxidized selectively to the corresponding ketones.