Practical P-Chiral Phosphane Ligand for Rh-Catalyzed Asymmetric Hydrogenation
作者:Duan Liu、Xumu Zhang
DOI:10.1002/ejoc.200400690
日期:2005.2
conformationally rigid P-chiral bis(trialkylphospholane) ligand 2 (DuanPhos) has been prepared in both enantiomeric forms through a concise syn-thesis. Rh-2 complex has exhibited remarkably high enantio-selectivities (up to >99% ee) and reactivities (up to 10,000 TON) for the hydrogenation of a wide variety of functionalized prochiral alkenes (5 different types), which provides a very practical catalytic system
Novel chiralmonodentate phosphorus ligands, SIPHOS, were conveniently synthesized from 1,1‘-spirobiindane-7,7‘-diol. The Rh complexes of SIPHOS can catalyze the hydrogenation of α-dehydroaminoesters in mild conditions, providing α-amino acid derivatives in up to 99% ee. Enamides and β-dehydroamino esters can also be hydrogenated in good to excellent enantioselectivities (up to 99% and 94% ee, respectively)
<i>Carica papaya</i>Lipase Catalysed Resolution of β-Amino Esters for the Highly Enantioselective Synthesis of (<i>S</i>)-Dapoxetine
作者:Pengyong You、Jian Qiu、Erzheng Su、Dongzhi Wei
DOI:10.1002/ejoc.201201055
日期:2013.1
CPL-catalysed resolution. The mechanism of the CPL-catalysed enantioselective alcoholoysis of the amino acids is discussed to delineate the substrate requirements for CPL-catalysed resolution. Finally, the reaction was scaled up, and the products were separated and obtained in good yields (≥ 80 %). The (S)-3-amino-3-phenylpropanoic acid obtained was used as a key chiral intermediate in the synthesis
Highly Efficient Synthesis of Chiral β-Amino Acid Derivatives via Asymmetric Hydrogenation
作者:Wenjun Tang、Xumu Zhang
DOI:10.1021/ol026935x
日期:2002.11.1
The Rh-TangPhos complex is an efficient hydrogenation catalyst for making chiral beta-amino acid derivatives. With the Rh-TangPhos system, high enantioselectivities (up to 99.6%) and turnover numbers have been obtained in the hydrogenation of E/Z isomeric mixtures of both beta-alkyl and beta-aryl beta-(acylamino)acrylates. [reaction: see text]
Practical Rh(I)-Catalyzed Asymmetric Hydrogenation of β-(Acylamino)acrylates Using a New Unsymmetrical Hybrid Ferrocenylphosphine−Phosphoramidite Ligand: Crucial Influence of an N−H Proton in the Ligand
作者:Xiang-Ping Hu、Zhuo Zheng
DOI:10.1021/ol047748x
日期:2005.2.1
Excellent enantioselectivities and high turnovers (S/C = 5000) were achieved in the Rh(l)-catalyzed asymmetric hydrogenation of both beta-aryl-and beta-alkyl-beta-(acylamino)acrylates with a new unsymmetrical hybrid ferrocenylphosphine-phosphoramidite ligand, and the presence of an N-H proton in the ligand was demonstrated to have a crucial role in the enantioselectivity.