Two targets from one intermediate: A new rearrangement of vinylcyclopropane into skipped diene is reported. The fundamental understanding of its mechanism obtained by a combined experimental and computational study enabled the development of divergent methodologies toward cyclopentene or skipped diene in a highly selective and controlled manner.
A highly enantioselective synthesis of functionalized cyclopentanoids by a formal asymmetric (4+1) annulation strategy was developed. The methodology consists of a stereoselective cyclopropanation reaction between chiral sulfur ylides and 1,3‐dienes followed by a, in situ, stereospecific MgI2‐catalyzed rearrangement of vinylcyclopropanes. This method is distinguished by a remarkable compatibility with
Diastereoselective Synthesis of Vinylcyclopropanes from Dienes and Sulfur Ylides
作者:Raphaël Robiette、Jacqueline Marchand-Brynaert
DOI:10.1055/s-2008-1032080
日期:——
The reaction of aryl- and vinyl-stabilized sulfonium ylides with electron-poor dienes has been investigated. Clean cyclopropanation to 2-aryl- and 2-vinyl-substituted vinylcyclopropanes, with high regio- and stereocontrol, was observed. This new diastereoselective strategy was applied to formal synthesis of lamoxirene and dictyopterene B.
An efficient two-step no purification protocol for the synthesis of enolizable α-subtituted β,γ-unsaturated aldehydes is reported. The developed strategy involves two steps, epoxidation and Meinwald rearrangement, to result in a formal one-carbon homologation of α,β-unsaturatedaldehydes enabling the insertion of a CHR unit.