Easily Accessible Halohydrin Esters as Advantageous Hydroxyethylation Reagents

Abstract Halohydrin esters are potentially versatile synthetic reagents, but their conventional synthesis commonly involves hazardous ethylene oxide. An economic, mild, safe, and scalable one-step halohydrin esters synthesis was achieved from easily accessible NaX, concentrated sulfuric acid, and polyol esters. The halohydrin ester products were applied in hydroxyethylation reactions with various nucleophiles in place of highly hazardous and toxic ethylene oxide. Repetition of the protocol allowed unsymmetric difunctionalization of diol esters. The mechanism likely involves an acyloxonium intermediate and proceeds through neighboring group participation.