α-Phosphono Lactone Analogues of Farnesyl Pyrophosphate: An Asymmetric Synthesis via Ring-Closing Metathesis
作者:Yanming Du、David F. Wiemer
DOI:10.1021/jo0202233
日期:2002.8.1
excess of strong base required for the rearrangement. A procedure for C-P bond formation based on generation of the lactone enolate, reaction with a P(III) reagent, and oxidation was successful in providing the racemic alpha-phosphono lactone, in part, because only 1 equiv of strong base was required. The same strategy for phosphonate synthesis then was applied to the nonracemic farnesyl lactone, prepared
制备了外消旋和非外消旋形式的法呢醇的α-膦酰基内酯衍生物,以提供新型的法呢基焦磷酸盐类似物。通过重排衍生自母体内酯的磷酸乙烯基酯试图制备外消旋α-膦酰基内酯会导致重排和内酯开环,这表明法呢基内酯对于重排所需的过量强碱不稳定。基于生成内酯烯醇酸酯,与P(III)试剂反应以及氧化的CP键形成过程成功地提供了外消旋的α-膦酰基内酯,部分原因是仅需要1当量的强碱。然后将相同的膦酸酯合成策略应用于非外消旋法呢基内酯,通过包括将法呢醛与非外消旋硼烷试剂进行烯丙基化,产物醇与丙烯酰氯的反应以及通过闭环易位形成不饱和内酯的顺序制备。一种类似的策略是通过六步法从法呢醛得到相应的外消旋α-膦酰基内酰胺。