Enantioselective hydrogenation of some alpha,beta -unsaturated nitriles and their corresponding methyl esters bearing a phthalimidomethyl substituent at the alpha -carbon using Rh-DuPHOS catalysts afforded beta -amino acid precursors with modest e.e.s of up to 48%. Hydrogenation of the alpha,beta -unsaturated methyl esters using a Ru-BINAP catalyst gave higher e.e.s of up to 84%. Method development for the determination of the enantiomeric excesses of these derivatives using chiral HPLC is also reported. (C) 2001 Elsevier Science Ltd. All rights reserved.
A combinatorial approach to the identification of self-assembled ligands for rhodium-catalysed asymmetric hydrogenation
作者:Joerg Wieland、Bernhard Breit
DOI:10.1038/nchem.800
日期:2010.10
iterative library deconvolution strategy to identify the optimal catalyst. As a test case, rhodium-catalysed asymmetrichydrogenation was studied and, from a library of 120 self-assembling catalysts, highly enantioselective catalysts for the asymmetrichydrogenation of different olefinic substrates were identified within 17 experiments. Comparison of the results of the iterative library deconvolution
作者:Dilek Saylik、Eva M. Campi、Andrew C. Donohue、W.Roy Jackson、Andrea J. Robinson
DOI:10.1016/s0957-4166(01)00097-0
日期:2001.3
Enantioselective hydrogenation of some alpha,beta -unsaturated nitriles and their corresponding methyl esters bearing a phthalimidomethyl substituent at the alpha -carbon using Rh-DuPHOS catalysts afforded beta -amino acid precursors with modest e.e.s of up to 48%. Hydrogenation of the alpha,beta -unsaturated methyl esters using a Ru-BINAP catalyst gave higher e.e.s of up to 84%. Method development for the determination of the enantiomeric excesses of these derivatives using chiral HPLC is also reported. (C) 2001 Elsevier Science Ltd. All rights reserved.
Rhodium-Catalyzed Enantioselective Hydrogenation of β-Phthalimide Acrylates to Synthesis of β<sup>2</sup>-Amino Acids
[Structure: see text] The enantioselectivehydrogenation of beta-phthalimide acrylates provides the corresponding chiral beta2-amino acids in excellent enantiomeric excess catalyzed by Rh-monophosphorus.