title: A new class of ammonium ylid for [2,3]-sigmatropic rearrangement reactions: ene-endo-spiro ylids.
abstract: The first examples of sigmatropic rearrangements of ene-endo-spirocyclic, tetrahydropyridine-derived ammonium ylids are reported. Thus, spiro[6.7]-ylids rearrange primarily by a [2,3]-pathway, whereas the analogous [6.6]-ylids rearrange by [1,2]- and [2,3]-mechanisms in roughly equal proportions. This method serves as a rapid entry to the core of a range of alkaloids bearing a pyrrolo[1,2-a]azepine or octahydroindolizidine nucleus.
authors.affiliation: School of Chemistry, University of Reading, UK.
authors.forename: Edward
authors.initials: E
authors.lastname: Roberts
authors.forename: Julien P
authors.initials: JP
authors.lastname: Sançon
authors.forename: J B
authors.initials: JB
authors.lastname: Sweeney
mesh_terms: D000470:Alkaloids / Q000138:chemical synthesis / Q000737:chemistry; D015394:Molecular Structure; D000644:Quaternary Ammonium Compounds / Q000737:chemistry* / Q000145:classification; D041901:Stemonaceae / Q000737:chemistry
chemical_list: D000470:Alkaloids; D000644:Quaternary Ammonium Compounds