Synthesis of β,γ-unsaturated ketones from acid chlorides through carbon-pentamethylcyclopentadienyl bond formation and cleavage

Article abstract of DOI:10.1246/bcsj.80.2400

Reaction of acid chlorides with lithium pentamethylcyclopentadienide afforded the corresponding pentamethyl-cyclopentadienyl ketones in high yield. These ketones were treated with an allylaluminum reagent to form the corresponding 3-butenyl alcohols. Removal of pentamethylcyclopentadiene upon heating or treatment with a catalytic amount of trichloroacetic acid yielded the corresponding β,γ-unsaturated ketones in good yields.