Kumulierte Ylide XX.<sup>1</sup>Synthesen (<i>E</i>)-α,β-ungesättigter macrocyclischer Lactone durch intramolekulare Wittig-Olefinierung via Triphenylphosphoranylidenketen<sup>2</sup>
作者:Hans Jürgen Bestmann、Rainer Schobert
DOI:10.1055/s-1989-27271
日期:——
Cumulated Ylides XX.1 Syntheses of (E)-α,β-Unsaturated Macrocyclic Lactones by Intramolecular Wittig-Olefination via Triphenylphosphoranylideneketene2 Two methods for closure of macrocyclic lactone rings by intramolecular Wittig reaction of (Ï-oxoalkoxy)carbonylmethylenetriphenylphosphoranes are described. The latter are easily accessible by addition of the appropriate (free or protected) Ï-hydroxyalkanals to the cumulated ylide triphenylphosphoranylideneketene. Examples are then given for the use of these methods in natural product synthesis.