title: Coinage metals-catalyzed cascade reactions of aryl alkynylaziridines: silver(I)-single vs gold(I)-double cyclizations.
abstract: Alkynylaziridines carrying an aryl group could be efficiently converted into aminoallenylidene isochromans, isoquinolines, or tetrahydronaphtalenes with silver(I) salts and into 1-azaspiro[4.5]decane derivatives with gold(I) complexes. Mechanistic investigations revealed that both Ag- and Au-catalyzed reactions involved a Friedel-Crafts type intramolecular reaction leading to an allene and that Au also rapidly promoted a second intramolecular cyclization of the aminoallene intermediate to the corresponding spiro derivative. Stereochemical investigations suggested an anti-SN(2)'-type pathway for the first cyclization leading to a stereodefined allene, which could then be cyclized to the corresponding stereodefined spiro product. These results highlight the duality between oxo- or azaphilicity and alkynophilicity of Ag and Au as well as their complementarity in terms of reactivity.
authors.affiliation: Laboratoire de Synthèse et Réactivité Organiques UMR 7177 associé au CNRS, Institut de Chimie, Université de Strasbourg, 4 rue Blaise Pascal, 67070 Strasbourg, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Kern
authors.forename: Aurélien
authors.initials: A
authors.lastname: Blanc
authors.forename: Solène
authors.initials: S
authors.lastname: Miaskiewicz
authors.forename: Michelle
authors.initials: M
authors.lastname: Robinette
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Weibel
authors.forename: Patrick
authors.initials: P
authors.lastname: Pale