An Effective and Highly Stereoselective Julia Olefination of Cyclopropyl Carbinol Mediated by CeCl₃·7H₂O/NaI

An efficient and highly stereoselective synthesis of functionalized trisubstituted E-olefins from cyclopropyl carbinol derivatives via a Julia-type olefination mediated by an intriguing Lewis acidic system consisting of CeCl₃·7H₂O and NaI in refluxing acetonitrile is reported. This facile olefination allows for the iterative incorporation of methylcyclopropyl ketone as a C₅ prenylation synthon in the synthesis of acyclic terpenoids, as demonstrated in the facile synthesis of plaunotol 6E-isomer 12, a biologically significant diterpene diol, and naturally occurring diterpene 17.