Highly Regio- and Stereoselective Ring-Opening Reaction of γ-Alkenyl-γ-butyrolactones with Allysilanes in the Presence of Trimethyloxonium Salt Leading to Methyl 4,8-Alkadienoates

Article abstract of DOI:10.1246/bcsj.61.4051

The reaction of γ-alkenyl-γ-butyrolactones with allylic trimethylsilanes in the presence of trimethyl-oxonium tetrafluoroborate proceeded regio- and stereoselectively with an allylic rearrangement of the substrate to afford methyl (E)-4,8-alkadienoates in high yields.On the other hand, the ring opening of 4-hexen-6-olide afforded exclusively methyl (Z)-4,8-alkadienoates in high yields.The synthetic utility of the reaction was demonstrated by the short step synthesis of β-sinensal and β-farnesene.