Abstract
Free radical reactions have recently emerged as a powerful tool in organic synthesis, especially in the synthesis of organofluorine compounds. We have been developing the novel methods for the synthesis of fluorine compounds using radical species. We would like to report here the following two radical reactions as tools for the synthesis of the promising synthetic intermediates for organofluorine compounds. 1) A wide variety of fluoroalkylated products can be prepared using fluoroalkyl radicals which are much more reactive for olefins than alkyl radicals. However, the reactions of perfluoroalky radicals with unsaturated molecules in the presence of oxygen have rarely been employed for organic synthesis, because of the high reactivity of fluoroalkyl radicals with oxygen. We found simultaneous introduction of perfluoroalkyl radical and molecular oxygen into olefin to give perfluoroalkylated alcohol and ketone. 2) Ring-opening reactions of gem-difluorocyclopropyl ketones are known. We investigated the radical reactions of gem-difluorocyclopropyl aldehyde with silyl radical, and found the ring-opening of the aldehyde to give fluorinated silyl enol ether under neutral conditions.
