title: Synthesis of enantioenriched azo compounds: organocatalytic Michael addition of formaldehyde N-tert-butyl hydrazone to nitroalkenes.
abstract: The unprecedented diaza-ene reaction of formaldehyde N-tert-butyl hydrazone with nitroalkenes can be efficiently catalyzed by an axially chiral bis-thiourea to afford the corresponding diazenes in good to excellent yields (60-96%) and moderate enantioselectivities, up to 84 : 16 er; additional transformation of diazenes into their tautomeric hydrazones proved to be operationally simple and high-yielding, affording bifunctional compounds which represent useful intermediates for the synthesis of enantioenriched β-nitro-nitriles and derivatives thereof.
authors.affiliation: Departamento de Química Orgánica, Universidad de Sevilla, C/Prof. García González, 1, 41012 Sevilla, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Monge
authors.forename: Silvia
authors.initials: S
authors.lastname: Daza
authors.forename: Pablo
authors.initials: P
authors.lastname: Bernal
authors.forename: Rosario
authors.initials: R
authors.lastname: Fernández
authors.forename: José M
authors.initials: JM
authors.lastname: Lassaletta