An efficient synthesis and acylation of α-amino-β-keto-esters: Versatile intermediates in the synthesis of peptide mimetics.
作者:Jasbir Singh、Thomas D. Gordon、William G. Earley、Barry A. Morgan
DOI:10.1016/s0040-4039(00)60549-x
日期:1993.1
A flexible and high yield synthesis of α-amino-β-keto esters has been developed via acylation of the ketimine derivatives of α-aminoesters. These α-amino-β-keto-esters were acylated with chiral amino acid derivatives in 36–95% yields.
syn α-benzoylamido β-hydroxy esters through asymmetrictransferhydrogenation (ATH) with a tethered Rh(III)–DPEN complex via dynamic kinetic resolution (DKR) has been developed for the first time starting from α-benzoylamido β-keto esters. A variety of α-benzoylamido β-keto esters were converted under mild conditions into the corresponding syn α-benzoylamino β-hydroxy esters with high yields (up to 98%)
Diastereo‐ and Enantioselective Hydrogenation of α‐Amino‐β‐Keto Ester Hydrochlorides Catalyzed by an Iridium Complex with MeO‐BIPHEP and NaBAr
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: Catalytic Cycle and Five‐Membered Chelation Mechanism of Asymmetric Hydrogenation
Ir‐catalyzed asymmetric hydrogenation of α‐amino‐β‐keto ester hydrochlorides is described. This reaction proceeds through a dynamic kinetic resolution to produce anti‐β‐hydroxy‐α‐amino acid esters in a high diastereo‐ and enantioselective manner. Mechanistic studies have revealed that this unique asymmetric hydrogenation proceeds through reduction of the ketone moiety via the five‐membered transition state
PROCESS FOR PRODUCTION OF OPTICALLY ACTIVE BETA-HYDROXY- ALPHA-AMINOCARBOXYLIC ACID DERIVATIVES
申请人:Nissan Chemical Industries, Ltd.
公开号:EP1650185B1
公开(公告)日:2013-05-01
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
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.