title: Unexpected efficiency of non-C(2) -symmetric bis(hydroxyamide)-based zinc-chelate catalysts.
abstract: Asymmetric bis(hydroxyamide)-based zinc-chelate catalysts are able to promote the enantioselective addition of diethylzinc to benzaldehyde in the absence of titanium with yields and ees comparable, or inclusively superior, to their C(2) -symmetric analogues. This unexpected fact demonstrates that the previously established assumption on the necessity of using C(2) -symmetric bis(hydrdoxyamides) to generate C(2) -symmetric zinc-chelate catalysts can be discarded, which expand the possibilities for designing new ligands based on the interesting hydroxyl-amide functional grouping.
authors.affiliation: Departamento de Química Orgánica I, de Universidad Complutense de Madrid, Facultad de Ciencias Químicas, Ciudad Universitaria s/n, Madrid, Spain.
authors.forename: Esther M Márquez
authors.initials: EM
authors.lastname: Sánchez-Carnerero
authors.forename: Tomás
authors.initials: T
authors.lastname: de Las Casas Engel
authors.forename: Beatriz
authors.initials: B
authors.lastname: Lora Maroto
authors.forename: Santiago
authors.initials: S
authors.lastname: de la Moya Cerero