Hydrogenation of enantioenriched β‐hydroxy ketones promoted by the catalyst generated in situ from commercially available and inexpensive RuCl3 and PPh3 under hydrogen pressure allowed the efficient preparation of a variety of anti‐1,3‐diols in good yields and with a high level of diastereoselectivity. This method should be an interesting alternative to organoboron reagents for the diastereoselective reduction of β‐hydroxy ketones. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

[reaction: see text] An efficient economical alternative to the commonly used Evans' reagent for the diastereoselective reduction of beta-hydroxy ketones is reported. Thus, ruthenium-mediated hydrogenation of enantioenriched beta-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.