title: Catalytic enantioselective 1,3-dipolar cycloaddition of azomethine ylides with vinyl sulfones.
abstract: [reaction: see text] A general protocol for the enantioselective catalytic 1,3-dipolar cycloaddition of azomethine ylides with aryl vinyl sulfones is described. Nearly complete exo selectivity and enantioselectivities up to 85% ee are attained with Cu(CH(3)CN)(4)ClO(4)/Taniaphos as the catalyst system. The resulting enantioenriched 3-sulfonyl cycloadducts are versatile intermediates in the synthesis of 2,5-disubstituted pyrrolidines.
authors.affiliation: Departamento de Química Orgánica, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco 28049 Madrid, Spain.
authors.forename: Tomás
authors.initials: T
authors.lastname: Llamas
authors.forename: Ramón Gómez
authors.initials: RG
authors.lastname: Arrayás
authors.forename: Juan C
authors.initials: JC
authors.lastname: Carretero