1104494-04-3Relevant articles and documents
Rhodium-Catalyzed anti and syn Enantio- and Diastereoselective Transfer Hydrogenation of α-Amino β-Keto Ester Hydrochlorides through Dynamic Kinetic Resolution
Llopis, Quentin,Férard, Charlène,Guillamot, Gérard,Phansavath, Phannarath,Ratovelomanana-Vidal, Virginie
, p. 3357 - 3363 (2016)
A mild catalytic asymmetric transfer hydrogenation of a series of α-amino β-keto ester hydrochlorides catalyzed by a rhodium(III) complex is reported. The use of the formic acid/triethylamine system as the hydrogen donor source provided the corresponding anti and syn amino alcohols with complete conversions, fair diastereoselectivities (up to 97:3 dr), and high enantioselectivities (ee up to >99%).
Rhodium-mediated asymmetric transfer hydrogenation: A diastereo- and enantioselective synthesis of: Syn -α-amido β-hydroxy esters
Zheng, Long-Sheng,Férard, Charlène,Phansavath, Phannarath,Ratovelomanana-Vidal, Virginie
supporting information, p. 283 - 286 (2018/01/12)
The preparation of syn α-benzoylamido β-hydroxy esters through asymmetric transfer hydrogenation (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%) and diastereomeric ratios (up to >99:1 dr) as well as excellent enantioselectivities (up to >99% ee).
Diastereo- and enantioselective hydrogenation of α-amino-β-keto ester hydrochlorides catalyzed by an iridium complex with MeO-BIPHEP and NaBArF: Catalytic cycle and five-membered chelation mechanism of asymmetric hydrogenation
Maeda, Tsukuru,Makino, Kazuishi,Iwasaki, Masamichi,Hamada, Yasumasa
supporting information; experimental part, p. 11954 - 11962 (2011/01/12)
The development of 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 involving the chelation between the oxygen of the ketone and the nitrogen of the amine function. The relationship studies between the hydrogen pressure and the stereoselectivity have disclosed two mechanisms dependent on hydrogen pressure. Under low hydrogen pressure (15 atm), the reaction rate proportionally increased with the hydrogen pressure. However, under the high hydrogen conditions, the reaction rate exponentially accelerated along with the increasing hydrogen pressure, which suggests the participation of two or more of hydrogen atoms. Apply some pressure: The Ir-catalyzed asymmetric hydrogenation of α-amino-β-keto ester hydrochlorides proceeds through a dynamic kinetic resolution to produce anti-β-hydroxy-α-amino acid esters in a high diastereo- and enantioselective manner (see scheme). Mechanistic studies revealed that this unique asymmetric hydrogenation proceeds through reduction of the ketone moiety via the five-membered transition state.
