| Abstract
| - At low temperature 1-alkoxy-1,3-dienes add to sulfur dioxide activated by a Lewis or Brønstedtacid and generate zwitterionic intermediates that can be quenched by enoxysilanes. The resultingβ,γ-unsaturated silyl sulfinates can be desilylated and reacted with methyl iodide to providepolyfunctional sulfones. Exploratory studies of this four-component synthesis of sulfones arereported. Enantiomerically pure derivatives containing up to three new stereogenic centers can beobtained using enantiomerically pure (E,E)-1-alkoxy-2-methylpenta-1,3-dienes derived from α-methyl benzyl alcohols, including the Greene's chiral auxiliary. The stereochemistry of the reactions isconsistent with a mechanism involving the suprafacial hetero-Diels−Alder addition of sulfur dioxideto the 1-alkoxy-1,3-dienes that are rapidly ionized into zwitterionic intermediates.
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