Total synthesis of gelsemoxonine

Abstract

The first total synthesis of gelsemoxonine has been accomplished. A divinylcyclopropane- cycloheptadiene rearrangement of the highly functionalized substrate successfully assembled the spiro-quaternary carbon center connected to the bicyclic seven-membered core structure. A one-pot isomerization reaction of the α,β-unsaturated aldehyde to the saturated ester via a trimethylsilyl cyanide-diazabicycloundecene (TMSCN-DBU) reagent combination allowed a facile and diastereoselective introduction of the latent nitrogen functionality in the unique azetidine moiety. © 2012 IUPAC.