or (S)-ar-turmerone is prepared in high enantiomeric excess from an intermediate, (R)-(+)-citronellic acid or (S)-(+)-3-p-tolylbutyric acid, which is easily prepared by the Sn2 type of ring opening reaction of (R)-(+)-β-methyl-β-propiolactone with homoprenylmagnesium bromide in the presence of a copper(I) salt or di-p-tolylcuprate.
由中间体(R)-(+)-制备对映体过量的旋光性萜烯,例如(R)-(+)-
香茅醇,(R)-(+)-普勒高酮或(S)-ar-异
黄酮。
柠檬酸或(S)-(+)-3-
对甲苯基丁酸,可通过(R)-(+)-β-甲基-
β-丙内酯与同异
戊烯基
溴化镁在室温下开环反应的Sn2型轻松制备
铜(I)盐或二
对甲苯甲酸铜盐的存在。