The Ru(II)-catalyzed hydrogenation of α-amino-β-keto esters as their hydrochloride salts affords preparation of the corresponding anti
α-amino-β-hydroxy esters under mild conditions with high diastereoselectivities and enantioselectivities via dynamic kinetic resolution.
anti-α-amino β-hydroxyesters with high levels of selectivity by the use of Ru-SYNPHOS® catalysts is reported. The key transformations include asymmetric hydrogenations of α-N-substituted β-keto esters protected as α-amido or α-amino hydrochloride derivatives, respectively. The RuII-catalyzed hydrogenation of α-amino β-keto ester hydrochlorides affords the corresponding anti-α-amino β-hydroxyesters with high
Development of Asymmetric Transfer Hydrogenation with a Bifunctional Oxo-Tethered Ruthenium Catalyst in Flow for the Synthesis of a Ceramide (<scp>d</scp>-<i>erythro</i>-CER[NDS])
development of an efficient synthetic route for an opticallyactive ceramide compound (d-erythro-CER[NDS]) is described. The route proceeds through asymmetric transfer hydrogenation in a pipes-in-series flow reactor with oxo-tethered ruthenium complex-catalyzed dynamic kinetic resolution. This synthesis was accomplished without any expensive reagents, and none of the intermediates required isolation
A Sphingolipid Fatty Acid Constituent Made by Alkyne
<i>trans</i>
‐Hydrogenation: Total Synthesis of Symbioramide
作者:Karin Radkowski、Alois Fürstner
DOI:10.1002/adsc.202200540
日期:2022.10.4
acid ((−)-2) is reported, which is the fatty acid constituent of numerous sphingolipids of biological significance. Key to success was the chemoselective trans-hydrogenation of a functionalized propargylic alcohol precursor with [Cp*RuCl]4 as the catalyst, followed by lipase-catalyzed resolution of the racemic product. (−)-2 then served the shortest totalsynthesis of the marinenaturalproduct symbioramide