Formation of Carbon Quaternary Stereogenic Center in Acyclic Systems via a Sequence of Carbometalation–Intramolecular Cyclization–Silicon Activation

Abstract

The diastereoselective carbometalation reaction of cyclopropenyl esters followed by reaction with acylsilanes provides γ-silylated lactones that undergo a ‘sila-Grob’ fragmentation to give pyrone enolates as a new source of acyclic δ-diketones, δ-keto acid, and δ-keto ester derivatives possessing a quaternary stereocenter.