Synthesis of 3-(1-hydroxyalkyl)-5H-furan-2-ones: Study of their reaction with halogens
作者:Angel Calderón、Pedro de March、Mustafa el Arrad、Josep Font
DOI:10.1016/s0040-4020(01)86714-4
日期:1994.4
The synthesis of 3-(1-hydroxyalkyl)-5H-furan-2-ones; 4a–c, is reported. The reaction of lactones 4a and 4b with bromine under typical ionic bromination conditions gives as major product the unexpected substitution of the allylic hydroxyl group. Only the less hindered double bond in 4c gives some proportion of the normal addition product. The bromine chloride addition to 4c proceeds with 55% yield,
3-(1-羟烷基)-5 H-呋喃-2-酮的合成; 报告了4a–c。内酯4a和4b与溴在典型的离子溴化条件下的反应作为主要产物给出了烯丙基羟基的意外取代。只有在4c中受阻较小的双键才能给出正常加成产物的一定比例。将氯化溴添加到4c中的产率为55%,而内酯4a不添加BrCl。所有这些结果表明以下事实:卤素加到4的双键上至少遭受空间位阻。