alcohols 5, undergo benzeneselenenic acid elimination to transient ketene acetals 8 which afford γ, δ-unsaturated esters 9via the ester Claisen rearrangement (Scheme 2). Under the same conditions selenoxide 7h derived from benzyl alcohol 5h is converted back to benzyl alcohol with the concomitant formation of ethylphenylselenoacetate 12.
由简单的两步法由单环和双环烯丙基醇5制备的苯
硒基
乙醛混合
缩醛7经过苯
硒酸消除,生成瞬态
乙烯酮缩醛8,后者通过酯Claisen重排反应得到γ,δ-不饱和酯9 (方案2)。在相同条件下,衍生自
苄醇5h的亚
硒酸酯7h被转化回
苄醇,并伴随形成
乙基苯基
硒乙酸乙酯12。