An Effective and Highly Stereoselective Julia Olefination of Cyclopropyl Carbinol Mediated by CeCl<sub>3</sub>·7H<sub>2</sub>O/NaI

2005-07-07T00:00:00Z (GMT) by Wei-Dong Z. Li Yu Peng
An efficient and highly stereoselective synthesis of functionalized trisubstituted <i>E</i>-olefins from cyclopropyl carbinol derivatives via a Julia-type olefination mediated by an intriguing Lewis acidic system consisting of CeCl<sub>3</sub>·7H<sub>2</sub>O and NaI in refluxing acetonitrile is reported. This facile olefination allows for the iterative incorporation of methylcyclopropyl ketone as a C<sub>5</sub> prenylation synthon in the synthesis of acyclic terpenoids, as demonstrated in the facile synthesis of plaunotol 6<i>E</i>-isomer <b>12</b>, a biologically significant diterpene diol, and naturally occurring diterpene <b>17</b>.