title: Alkenyl Arenes as Dipolarophiles in Catalytic Asymmetric 1,3-Dipolar Cycloaddition Reactions of Azomethine Ylides.
abstract: The use of alkenyl arenes as dipolarophiles in the catalytic asymmetric 1,3-dipolar cycloaddition of azomethine ylides is reported. Under appropriate reaction conditions with a CuIor AgIcatalyst either the exo or the endo adduct was obtained with high stereoselectivity. This process provides efficient access to highly enantiomerically enriched 4-aryl proline derivatives. The observed results are compatible with the blockage of one prochiral face of the 1,3-dipole, as well as with the efficient transmission of electrophilicity towards the terminal carbon atom of the dipolarophile. This polarization results in a change from a concerted to a stepwise mechanism.
authors.affiliation: Dpto. Química Orgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, 28049, Madrid, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Pascual-Escudero
authors.affiliation: IKERBASQUE, Basque Foundation for Science, 48011, Bilbao, Spain.|Dpto. Química Orgánica I, Facultad de Química, Universidad del País Vasco (UPV/EHU) and Donostia International Physics Center (DIPC), 20018, San Sebastián/Donostia, Spain.
authors.forename: Abel
authors.initials: A
authors.lastname: de Cózar
authors.affiliation: Dpto. Química Orgánica I, Facultad de Química, Universidad del País Vasco (UPV/EHU) and Donostia International Physics Center (DIPC), 20018, San Sebastián/Donostia, Spain.
authors.forename: Fernando P
authors.initials: FP
authors.lastname: Cossío
authors.affiliation: Dpto. Química Orgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, 28049, Madrid, Spain.
authors.forename: Javier
authors.identifier: 0000-0001-6238-6533
authors.initials: J
authors.lastname: Adrio
authors.affiliation: Dpto. Química Orgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, 28049, Madrid, Spain.
authors.forename: Juan C
authors.identifier: 0000-0003-4822-5447
authors.initials: JC
authors.lastname: Carretero
keywords: 1,3-dipolar cycloaddition; azomethine ylides; density functional calculations; pyrrolidines; styrenes