Synthesis of functionalized 1-silyl-substituted dienes by regioselective cyclopropanation of 1-silyl-substituted butadienes with dibromocarbene followed by Ag I -promoted ring-opening of the resulting dibromocyclopropanes

Abstract

The reaction of 1-trimethylsilyl-substituted butadienes with dibromocarbene, generated from CHBr3 and KOH under phase-transfer conditions gave, regioselectively, the corresponding cyclopropane adduct. The ring formation occurs at the double bond away from the silyl substituent. Ag+-Promoted ring-opening of these cyclopropanes in the presence of different nucleophiles gave the corresponding functionalized butadienylsilanes.