The reaction of 2-acylamino-3, 3-dichloroacrylonitriles (1) with various mercaptans in the presence of base gives 2-acylamino-3, 3-bis (substituted mercapto) acrylonitriles (5) or 2-acylamino-3-chloro-3-(substituted mercapto) acrylonitriles (17), each in good yield, depending upon the amount of mercaptans used. Similar nucleophilic substitutions are possible with the corresponding amides (8, 9), N-acylamides (10), esters (7), and acid (11). Treating the 3-mercapto acrylic acid derivatives thus obtained with silver compounds, such as Ag2O, Ag2CO3, and CH3COOAg, gives an excellent new method for synthesizing 5-(substituted mercapto) oxazoles (4). The scope and limitations of this new cyclization are also described.
2-酰
氨基-3, 3-
二氯丙烯腈(1)与各种巯基在碱的存在下反应,生成2-酰
氨基-3, 3-双(取代巯基)
丙烯腈(5)或2-酰
氨基-3-
氯-3-(取代巯基)
丙烯腈(17),每种产物均有良好的产率,具体取决于使用的巯基数量。相应的
酰胺(8, 9)、N-
酰胺(10)、
酯(7)和酸(11)也可以进行类似的亲核取代反应。将获得的3-巯基
丙烯酸衍
生物与
银化合物(例如
Ag2O、Ag2CO3和CH3CO
OAg)处理,为合成5-(取代巯基)
噁唑(4)提供了一种优良的新方法。此新环化反应的适用范围和局限性也进行了描述。