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 trans-epoxide silanols rearrange into products with an erythro configuration; di-substituted cis-epoxide silanols give products with a threo configuration. We have used these reactions as key steps in the syntheses of (±)-solerone and (±)-muricatacin.