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New methodology for synthesis of hydroperoxides and peroxides: I. Peroxycarbenium-mediated carbon-carbon bond formation; II. Stereoselective dioxygenation of chiral allylstannanes
Abstract
Despite the importance of peroxides in biology, chemistry and medicine, synthetic approaches toward peroxide-containing natural products are constrained by the limited number of methods available for incorporation of the peroxide group. To extend the scope of peroxide synthesis, we investigated the synthesis of peroxides from monoperoxyacetals. Nucleophilic displacement of monoperoxyketals in the presence of Lewis acid provides a method for the synthesis of dialkylperoxides. The corresponding reaction of silylated monoperoxyacetals and electron-rich alkenes in the presence of Lewis acids was studied for the synthesis of dialkyl peroxides and alkyl hydroperoxides. We also investigated stereoselective carbon-carbon bond formation of peroxides using prochiral nucleophiles. Many aspects of these reactions can be explained via the formation of an intermediate peroxycarbenium ion. Low-temperature NMR studies were undertaken to gain an improved understanding of Lewis acid dependence and the possible nature of the reaction intermediates. In a different approach toward hydroperoxide synthesis, we also investigated the reaction of singlet oxygen with chiral allylstannanes. Singlet oxygenation of simple alkenes typically produces a regioisomeric mixture of racemic allyl hydroperoxides. Our analysis of this reaction suggested that a chiral allylstannane might undergo stereoselective oxygenation. The singlet oxygenation of chiral allylstannanes was studied as a method for the stereoselective introduction of the carbon-oxygen bond. We were able to demonstrate that the stereoselective addition of singlet oxygen to the optically enriched allylstannanes allows the conversion of an enentiomerically enriched propargyl alcohol into either enantiomer of an allyl hydroperoxide.
Subject Area
Organic chemistry
Recommended Citation
Lee, Richard J, "New methodology for synthesis of hydroperoxides and peroxides: I. Peroxycarbenium-mediated carbon-carbon bond formation; II. Stereoselective dioxygenation of chiral allylstannanes" (1996). ETD collection for University of Nebraska-Lincoln. AAI9715972.
https://digitalcommons.unl.edu/dissertations/AAI9715972