Direct anti-selective asymmetric hydrogenation of α-amino-β-keto esters through dynamic kinetic resolution using Ru-axially chiral phosphine catalysts—stereoselective synthesis of anti-β-hydroxy-α-amino acids
                                
                                    
                                        作者:Kazuishi Makino、Takayuki Goto、Yasuhiro Hiroki、Yasumasa Hamada                                    
                                    
                                        DOI:10.1016/j.tetasy.2008.12.024
                                    
                                    
                                        日期:2008.12
                                    
                                    The asymmetric hydrogenation of alpha-amino-beta-keto esters using ruthenium (Ru) anti-selectively proceeds via a dynamic kinetic resolution to afford anti-beta-hydroxy-alpha-amino acids with high enantiomeric purities, which are important chiral building blocks for the synthesis of medicines and natural products. A mechanistic investigation has revealed that the Ru-catalyzed asymmetric hydrogenation takes place via the hydrogenation of the double bond in the enol tautomer of the substrate. (C) 2009 Elsevier Ltd. All rights reserved.