Intramolecular Homolytic Displacements. 25. Efficient Access to Epoxides via Induced Decomposition of Unsaturated Peroxyketals Prepared by Addition of a Hydroperoxide to 2-Methoxypropene
摘要:
The synthetic potential of homolytically induced decompositions of peroxyketals possessing a 1-methoxy-1-methylethoxy fragment, as a means of access to epoxides, was demonstrated. The propagation step of this free radical reaction proceeds via (i) the addition of a carbon-centered radical to the double bond followed by an S(H)i reaction on the peroxidic bond with the generation of a 1-methoxy-1-methylethoxy radical, (ii) formation of a methyl radical from the latter by beta-elimination, and (iii) regeneration of the carbon-centered-radical via iodine atom abstraction by the methyl radical from an alkyl iodide. These reactions afforded various functionalized epoxides in good yields.
Intramolecular Homolytic Displacements. 25. Efficient Access to Epoxides via Induced Decomposition of Unsaturated Peroxyketals Prepared by Addition of a Hydroperoxide to 2-Methoxypropene
The synthetic potential of homolytically induced decompositions of peroxyketals possessing a 1-methoxy-1-methylethoxy fragment, as a means of access to epoxides, was demonstrated. The propagation step of this free radical reaction proceeds via (i) the addition of a carbon-centered radical to the double bond followed by an S(H)i reaction on the peroxidic bond with the generation of a 1-methoxy-1-methylethoxy radical, (ii) formation of a methyl radical from the latter by beta-elimination, and (iii) regeneration of the carbon-centered-radical via iodine atom abstraction by the methyl radical from an alkyl iodide. These reactions afforded various functionalized epoxides in good yields.