The highly chemo- and enantioselective hydrogenation of (E)-2-substituted-4-oxo-2-alkenoic acids was established for the first time using the Rh/JosiPhos complex, affording a series of chiral α-substituted-γ-keto acids with excellent results (up to 99% yield and >99% ee) and high efficiency (up to 3000 TON). In addition, the importance of this methodology was further demonstrated by a concise and gram-scale
Dynamic kinetic resolution of various α-amido-β-keto phosphonates via asymmetrichydrogenation proceeded efficiently to give the corresponding β-hydroxy-α-amido phosphonates in high diastereo- and enantioselectivities (up to 99:1 syn/anti, 99.8% ee). The addition of catalytic amounts of CeCl3·7H2O is necessary to achieve both good selectivity and catalytic efficiency under mild reaction conditions
Iridium‐catalyzed asymmetric hydrogenation of β‐ketophosphonates with chiral ferrocenyl P,N,N‐ligands
作者:Yin‐Feng Ma、Chuan‐Jin Hou、De‐Quan Wei、Xinwei He、Ting‐Ting Chu、Xiu‐shuai Chen、Xiang‐Ping Hu
DOI:10.1002/aoc.6283
日期:2021.8
The asymmetrichydrogenation of β-ketophosphonates with chiral Ir/P,N,N-ligands catalyst has been developed. A series of β-ketophosphonates were hydrogenated, and the corresponding β-hydroxyphosphonates were obtained in high yields with good or excellent enantioselectivities under mild condition.
Stereoselective Synthesis of 4-Substituted Cyclic Sulfamidate-5-Phosphonates by Using Rh-Catalyzed, Asymmetric Transfer Hydrogenation with Accompanying Dynamic Kinetic Resolution
作者:Yeon Ji Seo、Jin-ah Kim、Hyeon-Kyu Lee
DOI:10.1021/acs.joc.5b01434
日期:2015.9.4
asymmetric transfer hydrogenation of 4-substituted cyclic sulfamidate imine-5-phosphonates produces the corresponding cyclic sulfamidate-5-phosphonates. The process employs a HCO2H/Et3N mixture as the hydrogen source and the chiral Rh catalysts, (R,R)- or (S,S)-Cp*RhCl(TsDPEN), and it takes place at room temperature within 1 h with high yields and high levels of stereoselectivity.
由动态动力学拆分驱动的4-取代的环状氨基磺酸亚胺-5-膦酸酯的不对称转移氢化反应生成了相应的环状氨基磺酸5-膦酸酯。该方法使用HCO 2 H / Et 3 N混合物作为氢源和手性Rh催化剂((R,R)-或(S,S)-Cp * RhCl(TsDPEN) 1 h具有高收率和高水平的立体选择性。
Enantioselective synthesis of chiral phosphonylated 2,3-dihydrofurans by copper catalyzed asymmetric formal [3+2] cycloaddition of propargylic esters with β-keto phosphonates
作者:Xiushuai Chen、Chuanjin Hou、Qing Li、Yanjun Liu、Ruifeng Yang、Xiangping Hu
DOI:10.1016/s1872-2067(16)62488-9
日期:2016.8
Copper catalyzed asymmetric formal [3+2] cycloaddition of propargylic esters to β-keto phosphonates for the synthesis of chiral phosphonylated 2,3-dihydrofurans was developed. By using a bulky and structurally rigid tridentate ketimine P,N,N ligand, a series of optically active phosphonylated 2,3-dihydrofurans were prepared in high yield and up to 92% ee.