Biphasic Glycerol/2‐MeTHF, Ruthenium‐Catalysed Enantioselective Transfer Hydrogenation of Ketones Using Sodium Hypophosphite as Hydrogen Donor. Issue 24 (2nd July 2013)

• Record Type: Journal Article
• Authors: Guyon, Carole; Métay, Estelle; Duguet, Nicolas; Lemaire, Marc
• Is Part Of: European journal of organic chemistry. Issue 24(2013)
• Page Start: 5439
• Page End: 5444
• Publication Date: 2013-07-02
• Subjects: Reduction -- Ketones -- Enantio­selectivity -- Ruthenium; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1002/ejoc.201300506
• Languages: English
• ISSNs: 1434-193X

Abstract

Abstract: 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 ). Abstract : Sodium hypophosphite has been used in the reduction of ketones in water (nine examples, 40–95 % yield). An original glycerol/2‐MeTHF biphasic solvent system has been developed for the enantioselective version of the reaction. This system allows the preparation of aryl alkyl alcohols with up to 97 % ee (22 examples).