Stereochemical study on an oxygen-directed olefin oxidation and subsequent oxygen cyclization: Differences between peracid and metal oxide-catalyzed hydroperoxide in oxidation reactions

Abstract Optically active (2 S ,4 R )-2-hydroxy-4-pentyl enol ether was prepared for the first time and subjected to hydroxy-directed oxidations at the olefinic group. Treatment with m -chloroperbenzoic acid and tert -butyl hydroperoxide/vanadium acetylacetonate resulted in the same stereoface differentiation at the olefin, with diastereomeric excesses as high as 79% and 92%, respectively, whereas the stereochemistry of the products of subsequent nucleophilic additions of the hydroxy group was opposite.