title: Gold(I)-catalyzed intramolecular cyclopropanation of dienynes.
abstract: Gold(I) complexes are the most active catalysts for the biscyclopropanation of dienynes to form tetracyclic compounds. PtII and ZnII are also able to promote the biscyclopropanation, although less efficiently. The configurations obtained in all cases with the use of gold(I) catalysts can be explained by the pathway proceeding through anti cyclopropyl gold carbenes. Similar intermediates are most probably involved in reactions catalyzed by RuII and PtII. Two different cyclopropanation pathways have been found; they depend on the structures of the cyclopropyl gold carbenes (anti or syn) and the relative arrangements of the metal carbenes and the alkenes.
authors.affiliation: Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, 43007 Tarragona, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Nieto-Oberhuber
authors.forename: Salomé
authors.initials: S
authors.lastname: López
authors.forename: M Paz
authors.initials: MP
authors.lastname: Muñoz
authors.forename: Eloísa
authors.initials: E
authors.lastname: Jiménez-Núñez
authors.forename: Elena
authors.initials: E
authors.lastname: Buñuel
authors.forename: Diego J
authors.initials: DJ
authors.lastname: Cárdenas
authors.forename: Antonio M
authors.initials: AM
authors.lastname: Echavarren