Dancing silanols: stereospecific rearrangements of silanol epoxides into silanoxy-tetrahydrofurans and silanoxy-tetrahydropyrans

Abstract

We have developed highly stereospecific rearrangements of silanol epoxides into 1'-silanoxy-tetrahydrofurans and 1'-silanoxy-tetrahydropyrans. Upon treatment with Ph₃CBF₄ and NaHCO₃ in CH₂Cl₂, di-substituted <i>trans</i>-epoxide silanols rearrange into products with an <i>erythro</i> configuration; di-substituted <i>cis</i>-epoxide silanols give products with a <i>threo</i> configuration. We have used these reactions as key steps in the syntheses of (±)-solerone and (±)-muricatacin.