title: Synthetic scope and DFT analysis of the chiral binap-gold(I) complex-catalyzed 1,3-dipolar cycloaddition of azlactones with alkenes.
abstract: The 1,3-dipolar cycloaddition between glycine-derived azlactones with maleimides is efficiently catalyzed by the dimeric chiral complex [(S a)-Binap·AuTFA]2. The alanine-derived oxazolone only reacts with tert-butyl acrylate giving anomalous regiochemistry, which is explained and supported by Natural Resonance Theory and Nucleus Independent Chemical Shifts calculations. The origin of the high enantiodiscrimination observed with maleimides and tert-butyl acrylate is analyzed using DFT computed at M06/Lanl2dz//ONIOM(b3lyp/Lanl2dz:UFF) level. Several applications of these cycloadducts in the synthesis of new proline derivatives with a 2,5-trans-arrangement and in the preparation of complex fused polycyclic molecules are described.
authors.affiliation: Departamento de Química Orgánica e Instituto de Síntesis Orgánica, Universidad de Alicante, Apdo. 99, 03080-Alicante, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Martín-Rodríguez
authors.affiliation: Departamento de Química Orgánica e Instituto de Síntesis Orgánica, Universidad de Alicante, Apdo. 99, 03080-Alicante, Spain.
authors.forename: Luis M
authors.initials: LM
authors.lastname: Castelló
authors.affiliation: Departamento de Química Orgánica e Instituto de Síntesis Orgánica, Universidad de Alicante, Apdo. 99, 03080-Alicante, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Nájera
authors.affiliation: Departamento de Química Orgánica e Instituto de Síntesis Orgánica, Universidad de Alicante, Apdo. 99, 03080-Alicante, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Sansano
authors.affiliation: Departamento de Química Orgánica I, Facultad de Química, Universidad del País Vasco, Apdo. 1072, E-20018 San Sebastián, Spain.
authors.forename: Olatz
authors.initials: O
authors.lastname: Larrañaga
authors.affiliation: Departamento de Química Orgánica I, Facultad de Química, Universidad del País Vasco, Apdo. 1072, E-20018 San Sebastián, Spain ; IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain.
authors.forename: Abel
authors.initials: A
authors.lastname: de Cózar
authors.affiliation: Departamento de Química Orgánica I, Facultad de Química, Universidad del País Vasco, Apdo. 1072, E-20018 San Sebastián, Spain.
authors.forename: Fernando P
authors.initials: FP
authors.lastname: Cossío
keywords: 1,3-dipolar cycloaddition; DFT; NICS; NTR; asymmetric catalysis; gold catalysis; oxazolones; prolines