RhIII -Catalyzed Asymmetric Transfer Hydrogenation of α-Methoxy β-Ketoesters through DKR in Water: Toward a Greener Procedure.

The asymmetric reduction of α-methoxy β-ketoesters through transfer hydrogenation with a new rhodium(III) complex was developed. The reaction was efficient in 2-MeTHF with formic acid/triethylamine or in water with sodium formate. The corresponding syn α-methoxy β-hydroxyesters were obtained with high diastereoselectivities and excellent levels of enantioselectivity through a dynamic kinetic resolution process.