title: Nickel-catalyzed transfer hydrogenation of ketones using ethanol as a solvent and a hydrogen donor.
abstract: We report a nickel(0)-catalyzed direct transfer hydrogenation (TH) of a variety of alkyl-aryl, diaryl, and aliphatic ketones with ethanol. This protocol implies a reaction in which a primary alcohol serves as a hydrogen atom source and solvent in a one-pot reaction without any added base. The catalytic activity of the nickel complex [(dcype)Ni(COD)] (e) (dcype: 1,2-bis(dicyclohexyl-phosphine)ethane, COD: 1,5-cyclooctadiene), towards transfer hydrogenation (TH) of carbonyl compounds using ethanol as the hydrogen donor was assessed using a broad scope of ketones, giving excellent results (up to 99% yield) compared to other homogeneous phosphine-nickel catalysts. Control experiments and a mercury poisoning experiment support a homogeneous catalytic system; the yield of the secondary alcohols formed in the TH reaction was monitored by gas chromatography (GC) and NMR spectroscopy.
authors: Facultad de Química, Universidad Nacional Autónoma de México, Circuito Interior, Ciudad Universitaria, Mexico City 04510, Mexico. juvent@unam.mx.
authors: Nahury
authors: N
authors: Castellanos-Blanco
authors: Alma
authors: A
authors: Arévalo
authors: Juventino J
authors: JJ
authors: García