DPAMPP in catalytic asymmetric reactions: enantioselective synthesis of l- homophenylalanine
摘要:
L-Homophenylalanine 1, a key intermediate of most commercially important ACE inhibitors, was prepared via catalytic asymmetric hydrogenation of (Z)-2-acetamido-4-phenylcrotonate 3a with a cationic rhodium complex of(1 R,2S)-DPAMPP, followed by acid-hydrolysis of the protecting groups in good yield with >99.9% enantioselectivity. (C) 2000 Elsevier Science Ltd. All rights reserved.
A series of opticallypure β-amino ketones have been synthesized in high enantioselectivities (ee > 99%) by Rh-DuanPhos-catalyzed asymmetric hydrogenation of readily prepared β-keto enamides. Further reduction of these β-amino ketones with hydrogen and Pd/C leads to the formation of a variety of protected enantiomerically pure γ-aryl amines (ee > 99%), which are key building blocks in many bioactive
Site-Selective Modification of α-Amino Acids and Oligopeptides via Native Amine-Directed γ-C(sp<sup>3</sup>)-H Arylation
作者:Feipeng Yuan、Zhen-Lin Hou、Pranab K. Pramanick、Bo Yao
DOI:10.1021/acs.orglett.9b03607
日期:2019.12.6
Site-selective modification of chemically and biologically valuable α-aminoacids and peptides is of great importance for biochemical study and pharmaceutical development. Few methods based on remote C(sp3)-H functionalization of aliphatic side-chains of peptides has been disclosed in recent years. In this report, we developed a novel approach for γ-C(sp3)-H and γ-/δ-C(sp2)-H arylation of α-aminoacids with
Practical Enantioselective Hydrogenation of α-Aryl- and α-Carboxyamidoethylenes by Rhodium(I)-{1,2-Bis[(<i>o</i>-<i>tert</i>-butoxyphenyl)(phenyl)phosphino]ethane}
作者:Barbara Mohar、Michel Stephan
DOI:10.1002/adsc.201200780
日期:——
The rhodium(I)-1,2-bis[(o-tert-butoxyphenyl)(phenyl)phosphino]ethane} [Rh(I)-(t-Bu-SMS-Phos)] catalyst system displayed prime efficiency in the hydrogenation of large series of α-amidostyrenes and α-amidoacrylates. Up to >99.9% enantiomeric excesses coupled with very high reaction rates were attained operating routinely under 1–10 bar of hydrogen at 22 °C in methanol. Examples include industrial substrates
DiPAMPâs Big Brother â<i>i-</i>Pr-SMS-Phosâ Exhibits Exceptional Features Enhancing Rhodium(I)-Catalyzed Hydrogenation of Olefins
作者:Michel Stephan、Damjan SÌterk、Barbara Mohar
DOI:10.1002/adsc.200900621
日期:2009.11
Switching Knowles DiPAMP’s DiPAMP=1,2-bis[(o-anisyl)(phenyl)phosphino]-ethane} MeO groups with i-PrO ones led to the i-Pr-SMS-Phos i-Pr-SMS-Phos=1,2-bis[(o-isoprop- oxyphenyl)(phenyl)phosphino]ethane} ligand which displayed a boosted catalyst activity coupled with an enhanced enantioselectivity in the rhodium(I)-catalyzed hydrogenation of a wide-range of representative olefinic substrates (dehydro-α-amido
Aminophosphine Phosphinites Derived from Chiral 1,2-Diphenyl-2-aminoethanols: Synthesis and Application in Rhodium-Catalyzed Asymmetric Hydrogenation of Dehydroamino Acid Derivatives
A series of chiral aminophosphine phosphinites DPAMPPs was synthesized from optically active 1,2-diphenyl-2-aminoethanols. The erythro-DPAMPPs were found to serve as excellent ligands for rhodium-catalyzed asymmetric hydrogenation of dehydroaminoacid derivatives. For an array of dehydroaminoacid precursors, remarkably high enantioselectivity (up to 98.4% e.e.) and reactivity (the ratio of substrate/catalyst