corresponding Grignard reagent and were used as a racemic mixture. The resulting γ-hydroxy α,β-epoxyesters were treated with thiophenol for transformation into α-phenylsulfanyl trisubstituted γ-butyrolactones. The syn,syn-lactones isomerize easily in basic media into the syn,anti structures. In order to explain this interconversion, a retroaldol–aldol sequence has been proposed and a sulfur–oxygen
研究了γ-羟基-α,β-不饱和酯的亲核环氧化的非对映选择性。通过用相应的
格氏试剂处理(E)-4-氧代-
2-丁烯酸乙酯获得γ-羟基-α,β-不饱和酯,并将其用作外消旋混合物。用
硫酚处理所得的γ-羟基α,β-环氧酯,以转化为α-苯基
硫烷基三取代的
γ-丁内酯。该SYN,顺式内酯在碱性介质进入很容易异构顺,反结构。为了解释这种相互转化,提出了逆醛醇-羟醛序列,并调用了
硫-氧相互作用来解释顺式。 分子内羟醛反应产生的α-
硫代羟醛的立体
化学偏好。