Facile and clean synthesis of α-alkenoyl ketene-(S,S)-acetals via the aldol condensation reactions in water
作者:Yan Ouyang、Dewen Dong、Wei Pan、Jie Zhang、Qun Liu
DOI:10.1016/j.tet.2006.08.040
日期:2006.10
The aldol condensation reactions of α,α-diacetyl ketene-(S,S)-acetals, 1a and 1b, with aromatic aldehydes 2 in the presence of NaOH in water have been investigated. At room temperature, the base-mediated condensations proceed smoothly to afford the corresponding mono-condensed products, α-alkenoyl ketene-(S,S)-acetals 3, in high yields. At reflux temperature, the reactions produce high yields of symmetric
研究了α,α-二乙酰基乙烯酮-(S,S)-乙缩醛1a和1b在水中存在NaOH的情况下与芳香醛2的醛醇缩合反应。在室温下,碱介导的缩合反应平稳进行,以高收率得到相应的单缩合产物,α-链烯基烯酮-(S,S)-缩醛3。在回流温度下,当使用2当量的醛时,反应产生高产率的对称双缩合的α,α-二烯基烯酮-(S,S)-乙缩醛4。此外,化合物3可以与不同的醛缩合,得到不对称的双缩合α,α-二烯基烯酮-(S,S)-缩醛5。