N-(α-Ethoxyallyl)benzotriazole: A Novel Propenoyl Anion Synthon Route to Vinyl Ketones

Article abstract of DOI:10.1021/jo00128a035

Lithiation with butyllithium of (N-(α-ethoxyallyl)benzotriazole (2) (readily prepared in quantitative yield on a large scale from benzotriazole and acrolein diethyl acetal (9)) followed by reaction of lithio derivative 14 with halides, α,β-unsaturated esters, α,β-unsaturated ketones, and aldehydes gave exclusively α-alkylation adducts.These adducts are hydrolyzed under extremely mild conditions, enabling convenient syntheses of vinyl ketones 16 and functionalized vinyl ketones 21, 22, 24, and 27.