RuCl3/PPh3: An Efficient Combination for the Preparation of Chiral 1,3-anti-Diols through Catalytic Hydrogenation
journal contributionposted on 04.01.2007, 00:00 by Olivier Labeeuw, Christophe Roche, Phannarath Phansavath, Jean-Pierre Genêt
An efficient economical alternative to the commonly used Evans' reagent for the diastereoselective reduction of β-hydroxy ketones is reported. Thus, ruthenium-mediated hydrogenation of enantioenriched β-hydroxy ketones using RuCl3 associated to achiral monophosphines allowed the preparation of a series of 1,3-anti-diols in good yields and with a high level of diastereoselectivity. A short screening of ligands pointed out PPh3 as the most effective phosphine, and PCy3 afforded the 1,3-diols with an unexpected moderate syn selectivity.