title: Highly enantioselective electrophilic amination and michael addition of cyclic beta-ketoesters induced by lanthanides and (S,S)-ip-pybox: the mechanism.
abstract: High enantioselection is obtained in Michael additions of cyclic beta-ketoesters in the presence of lanthanium triflates and (S,S)-ip-pybox. Intermediates based on simultaneous coordination of the lanthanide to both (S,S)-ip-box and beta-ketoester (in keto and enolate forms) are detected by means of ESI mass spectrometry and NMR experiments, and a possible mechanism is proposed through theoretical calculations.
authors.affiliation: Department of Chemistry, Universitat Autonoma de Barcelona, Cerdanyola, 08193-Barcelona, Spain.
authors.forename: Josep
authors.initials: J
authors.lastname: Comelles
authors.forename: Alex
authors.initials: A
authors.lastname: Pericas
authors.forename: Marcial
authors.initials: M
authors.lastname: Moreno-Mañas
authors.forename: Adelina
authors.initials: A
authors.lastname: Vallribera
authors.forename: Galí
authors.initials: G
authors.lastname: Drudis-Solé
authors.forename: Agusti
authors.initials: A
authors.lastname: Lledos
authors.forename: Teodor
authors.initials: T
authors.lastname: Parella
authors.forename: Anna
authors.initials: A
authors.lastname: Roglans
authors.forename: Santiago
authors.initials: S
authors.lastname: García-Granda
authors.forename: Laura
authors.initials: L
authors.lastname: Roces-Fernández