The reactivity profile of allylic bromides (derived from the Morita-Baylis-Hillman reaction) towards thiourea derivatives and further transformations of the resulting isothiuronium bromides are described. Isothiuronium salts, prepared in near quantitative yields, undergo a selective acetylation or a base-promoted intramolecular cyclization to give 2-amino-1,3-thiazin-4-ones in good overall yields.
描述了烯丙基
溴化物(源自 Morita-Baylis-Hillman 反应)对
硫脲衍
生物的反应性以及所得异
硫脲溴化物的进一步转化。异
硫脲盐以接近定量的产率制备,经过选择性乙酰化或碱促进的分子内环化,以良好的总产率得到 2-amino-1,3-thiazin-4-ones。除了反应、条件和纯化步骤的简单性之外,这里介绍的方法还提供了高纯度的产品。X 射线衍射分析明确证实了代表性化合物的结构特征。