Selective oxidation of tertiary-secondary vic-diols to alpha-hydroxy ketones by dioxiranes

Isolated dimethyldioxirane (1a) and methyl(trifluoromethyl)dioxirane (1b) efficiently afford the conversion of bicyclic diols bicyclo(2.2.2]octane-1,2-diol (2) and (+)-pinane-2,3-diol (6), of tricyclic diols adamantane-1,2-diol (3), homoadamantane-3,4-diol (4), and of homopentaprismane-3,4-diol (5) into the corresponding alpha-hydroxy ketones in high yields and under mild conditions. In the oxidation of (+)-pinane-2,3-diol (6), (-)-2-hydroxy-3-pinanone (11) is obtained in optical yield >97% with retention of configuration.