Biphasic Glycerol/2-MeTHF, Ruthenium-Catalysed Enantioselective Transfer Hydrogenation of Ketones Using Sodium Hypophosphite as Hydrogen Donor

Carole Guyon (1) , Estelle Métay (1) , Nicolas Duguet (1) , Marc Lemaire (1)

1 CASYEN - Catalyse Synthèse et Environnement

Sodium hypophosphite has been used as an efficient hydrogen donor in the transfer hydrogenation of aliphatic and aromatic ketones in the presence of [RuCl2(p-cymene)]2 and 2,2′-bipyridine in water. The corresponding alcohols were isolated in moderate to excellent yields (39–95 %). Good chemoselectivity was observed with ester, nitrile and halide functionalities in the ketones not being reduced. An enantioselective version of the reaction using [RuCl(p-cymene){(R,R)-TsDPEN}] as catalyst in a glycerol/2-MeTHF biphasic solvent mixture has been developed and allowed the reduction of (hetero)aromatic ketones with excellent chemo- and enantioselectivities (up to 97 % ee).

Mots clés: Reduction; Ketones; Enantioselectivity; Ruthenium

Domaines: Chimie organique; Catalyse

Carole Guyon, Estelle Métay, Nicolas Duguet, Marc Lemaire. Biphasic Glycerol/2-MeTHF, Ruthenium-Catalysed Enantioselective Transfer Hydrogenation of Ketones Using Sodium Hypophosphite as Hydrogen Donor. European Journal of Organic Chemistry, 2013, 2013 (24), pp.5439-5444. ⟨10.1002/ejoc.201300506⟩. ⟨hal-03249234⟩