title: A photocatalytic acid- and base-free Meerwein-Ponndorf-Verley-type reduction using a [Ru(bpy)3]2+/viologen couple.
abstract: A photocatalytic system to effect the Meerwein-Ponndorf-Verley reduction of carbonylic compounds to alcohols has been developed. The system comprises [Ru(bpy)3]2+ as a photosensitizer, triethanolamine as a sacrificial electron donor, viologen as an electron acceptor, and the carbonyl compound and iPrOH as Meerwein-Ponndorf-Verley reagents. The photocatalytic reaction can be performed in neat iPrOH or in 1-butyl-3-methylimidazolium ionic liquid. Mass spectrometric detection of the viologen hydride derivative VH+ confirms that this species is the reducing agent responsible for the carbonyl compound reduction. The reaction intermediates involved in the photocatalytic system have also been characterized by laser flash photolysis.
authors.affiliation: Instituto de Tecnología Química, Universidad Politécnica de Valencia, Camino de Vera s/n, 46022 Valencia, Spain.
authors.forename: Jose Raul
authors.initials: JR
authors.lastname: Herance
authors.forename: Belén
authors.initials: B
authors.lastname: Ferrer
authors.forename: Jose Luis
authors.initials: JL
authors.lastname: Bourdelande
authors.forename: Jordi
authors.initials: J
authors.lastname: Marquet
authors.forename: Hermenegildo
authors.initials: H
authors.lastname: Garcia