Hosomi‐Sakurai Allylation

Abstract The Lewis acid‐ or fluoride‐promoted allylation of various carbon electrophiles (e.g., aldehydes, ketones, aldimines, alkenes, imines, α,β‐unsaturated carbonyl compounds, acetals) with allyltrimethylsilane accompanied by the regiospecific transposition of allylic moiety and possible generation of new chiral center(s) is generally referred to as the Hosomi–Sakurai allylation. Many Lewis acids have been applied as promoters or catalysts for the allylation of acetals. For the allylation of aldehydes with substituted allylsilane, such as crotylsilane, the syn ‐homoallylic alcohols form predominantly from either cis ‐crotylsilane or trans ‐crotylsilane. This reaction has been improved to occur in the presence of a catalytic amount of Lewis acid using allylsilyl chlorides instead of allyltrimethylsilane and has wide applications in organic synthesis.