title: Harnessing the Electrophilicity of Keteniminium Ions: A Simple and Straightforward Entry to Tetrahydropyridines and Piperidines from Ynamides.
abstract: An efficient, modular and straightforward entry to tetrahydropyridines and piperidines is reported. This reaction is based on a formal intramolecular hydroalkylation of readily available, properly substituted ynamides which, upon simple activation under acidic conditions, generate highly reactive activated keteniminium ions whose reactivity can be finely controlled to induce a remarkably efficient [1,5]-hydride shift from unactivated C-H bonds and trigger a cationic cyclization which is complete within minutes.
authors.affiliation: Laboratoire de Chimie Organique, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50, CP160/06, 1050, Bruxelles, Belgium.
authors.forename: Morgan
authors.initials: M
authors.lastname: Lecomte
authors.affiliation: Laboratoire de Chimie Organique, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50, CP160/06, 1050, Bruxelles, Belgium. gevano@ulb.ac.be.
authors.forename: Gwilherm
authors.initials: G
authors.lastname: Evano
keywords: cationic cyclizations; hydride shift; keteniminium ions; piperidines; ynamides