对映体富集的α-羟基酰胺和β-氨基醇的合成已通过用氢硅烷将α-酮酰胺对映选择性还原而完成。通过使用(EtO)3 SiH作为还原剂,在手性Cu II /(S)-DTBM-SEGPHOS催化剂存在下还原了一系列α-酮酰胺,得到了具有出色对映选择性的相应光学活性α-羟基酰胺。此外,使用相同的手性铜催化剂,然后在(EtO)3 SiH存在下,用四正丁基氟化铵(TBAF)催化剂,一锅完全还原了α-酮酰胺的酮基和酰胺基。相应的手性β-氨基醇衍生物。
对映体富集的α-羟基酰胺和β-氨基醇的合成已通过用氢硅烷将α-酮酰胺对映选择性还原而完成。通过使用(EtO)3 SiH作为还原剂,在手性Cu II /(S)-DTBM-SEGPHOS催化剂存在下还原了一系列α-酮酰胺,得到了具有出色对映选择性的相应光学活性α-羟基酰胺。此外,使用相同的手性铜催化剂,然后在(EtO)3 SiH存在下,用四正丁基氟化铵(TBAF)催化剂,一锅完全还原了α-酮酰胺的酮基和酰胺基。相应的手性β-氨基醇衍生物。
Novel chiral stationary phases based on 3,5‐dimethyl phenylcarbamoylated β‐cyclodextrin combining cinchona alkaloid moiety
作者:Lunan Zhu、Junchen Zhu、Xiaotong Sun、Yaling Wu、Huiying Wang、Lingping Cheng、Jiawei Shen、Yanxiong Ke
DOI:10.1002/chir.23237
日期:2020.8
Novelchiral selectors based on 3,5‐dimethylphenylcarbamoylatedβ‐cyclodextrin connecting quinine (QN) or quinidine (QD) moiety were synthesized and immobilized on silica gel. Their chromatographic performances were investigated by comparing to the 3,5‐dimethylphenylcarbamoylatedβ‐cyclodextrin (β‐CD) chiralstationaryphase (CSP) and 9‐O‐(tert‐butylcarbamoyl)‐QN‐based CSP (QN‐AX). Fmoc‐protected
triflate and (R,R)-Ph-BOX as a catalyst. This method was successfully applied to a variety of 2-hydroxyalkanamides in high enantioselectivity with up to 92% ee, and then tosylated product was easily transformed into opticallyactive α-amino acid derivatives.
Chemo- and Enantioselective Reduction of α-Keto Amides to α-Hydroxy Amides using Reusable CuO-Nanoparticles as Catalyst
作者:Gollapalli Narasimha Rao、Govindasamy Sekar
DOI:10.1021/acs.joc.3c00090
日期:2023.3.17
(CuO-NPs) and (R)-(−)-DTBM SEGPHOS catalyzed chemo- and enantioselectivereduction of α-keto amides to α-hydroxy amides has been developed. The scope of the reaction has been studied with various α-keto amides containing electron-donating and electron-withdrawing groups affording the enantiomerically enriched α-hydroxy amides in good yields with excellent enantioselectivity. The CuO-NPs catalyst has been
Enantioselective Synthesis of α-Hydroxy Amides and β-Amino Alcohols from α-Keto Amides
作者:N. Chary Mamillapalli、Govindasamy Sekar
DOI:10.1002/chem.201503569
日期:2015.12.14
Synthesis of enantiomerically enriched α‐hydroxy amides and β‐amino alcohols has been accomplished by enantioselective reduction of α‐keto amides with hydrosilanes. A series of α‐keto amides were reduced in the presence of chiral CuII/(S)‐DTBM‐SEGPHOS catalyst to give the corresponding optically active α‐hydroxy amides with excellent enantioselectivities by using (EtO)3SiH as a reducing agent. Furthermore
对映体富集的α-羟基酰胺和β-氨基醇的合成已通过用氢硅烷将α-酮酰胺对映选择性还原而完成。通过使用(EtO)3 SiH作为还原剂,在手性Cu II /(S)-DTBM-SEGPHOS催化剂存在下还原了一系列α-酮酰胺,得到了具有出色对映选择性的相应光学活性α-羟基酰胺。此外,使用相同的手性铜催化剂,然后在(EtO)3 SiH存在下,用四正丁基氟化铵(TBAF)催化剂,一锅完全还原了α-酮酰胺的酮基和酰胺基。相应的手性β-氨基醇衍生物。