Three separate methods are reported for the formation of@-hydroxy acid derivatives from readily available substituted A2-isoxazolines. Cycloaddition of 2, 2-dimethylpropanenitrile oxide with a variety of olefins followed by reductive cleavage produces a'-tert-butyl@- hydroxy ketones. These are cleaved to@-hydroxy tert-butyl esters by Baeyer-Villiger oxidation with peroxytrifluoroacetic acid. In the second approach, a',@-dihydroxy ketones ...