Preparation of 5-Cyano-4,6-dimethyl-2<i>H</i>-pyran-2-one and 3-Cyano-5-methoxy-4-methyl-5<i>H</i>-furan-2-one via a One-Pot, Domino-Knoevenagel Process
作者:Prativa B. S. Dawadi、Johan Lugtenburg
DOI:10.1080/00397910903277904
日期:2010.8.5
5-Cyano-4,6-dimethyl-2H-pyran-2-one (1) has been prepared via a simple one-pot domino-Knoevenagel reaction starting from ethyl acetoacetate (2) and cyanoacetone (3). Similarly, a new racemic 3-cyano-5-methoxy-4-methyl-5H-furan-2-one (7) has been prepared from 1,1-dimethoxyacetone (6) and cyanoacetic acid (4). The new alkylidene derivatives (Z/E)-ethyl-4-cyano-3-methylbut-3-enoate (5), (Z/E)-ethyl
5-氰基-4,6-二甲基-2H-吡喃-2-one (1) 已通过简单的一锅多米诺-Knoevenagel 反应从乙酰乙酸乙酯 (2) 和氰基丙酮 (3) 开始制备。类似地,由 1,1-二甲氧基丙酮 (6) 和氰基乙酸 (4) 制备了新的外消旋 3-氰基-5-甲氧基-4-甲基-5H-呋喃-2-酮 (7)。新的亚烷基衍生物 (Z/E)-ethyl-4-cyano-3-methylbut-3-enoate (5), (Z/E)-ethyl 5-amino-4-cyano-3-methyl-5-oxopent- 3-烯酸酯 (9) 和 (2,2-二甲氧基-1-甲基亚乙基) 丙二腈 (11) 已通过 Knoevenagel 反应制备。以良好的收率轻松获得这些新化合物表明,乙酸铵/乙酸催化的 Knoevenagel 反应和多米诺-Knoevenagel 反应具有广泛的应用范围。