Reactions of (Aryloxy)oxosulfonium Ylides with Carbonyl Compounds

Article abstract of DOI:10.1021/jo00182a016

Reactions of (aryloxy)oxosulfonium salts with alkyllithium followed by the additon of carbonyl compounds gave β-aryloxy sulfones, β-aroyloxy sulfones, and α,β-unsaturated or β,γ-unsaturated sulfones in 1.4-17.9percent, 1.2-7.2percent, and 4.5-13.5percent yields, respectively.Ylides obtained by treatment of these sulfonium salts with n-BuLi reacted with carbonyl compounds to give betaines, which formed unusual four-membered cyclic alkoxyoxosulfonium salts.The aryloxy anions thus formed attacked β-carbons of these salts to afford β-aryloxy sulfones.The aroyloxy anion that might be formed by autoxidation also attacked β-carbons of these salts to afford β-aroyloxy sulfones.When these anions attacked the α- or γ-protones of these salts, unsaturated sulfones were obtained.This is the first example that the reaction of ylide with carbonyl compounds gave sulfone derivatives via four-membered cyclic alkoxyoxosulfonium salts that were produced by the intramolecular S_N2 mechanism.The yields of unsaturated sulfones were raised up to 35-60percent by a one-pot reaction.