ChemInform Abstract: Enantioselective Catalysis. Part 63. Optically Active Phosphines from Dicarboxylic Acids and Their Application to the Enantioselective Hydrogenation.

ChemInform ◽  
2010 ◽  
Vol 22 (27) ◽  
pp. no-no
Author(s):  
H. BRUNNER ◽  
W. ZETTLMEIER
Keyword(s):  
Dicarboxylic Acids ◽  
Enantioselective Hydrogenation ◽  
Optically Active ◽  
Enantioselective Catalysis

Asymmetrische Katalysen, 25 [1]. C5H5Mn(CO)2-Komplexe von optisch aktiven Chelatphosphanen als einzähnige Liganden in der enantioselektiven Katalyse / Asymmetric Catalyses, 25 [1]. C5H5Mn(CO)2 Complexes of Optically Active Chelate Phosphanes as Monodentate Ligands in Enantioselective Catalysis

1985 ◽  
Vol 40 (10) ◽  
pp. 1243-1249 ◽  
Author(s):  
Henri Brunner ◽  
Alfons Knott
Keyword(s):  
Cinnamic Acid ◽  
Enantioselective Hydrogenation ◽  
Optically Active ◽  
Enantioselective Catalysis ◽  
Dinuclear Complexes ◽  
Bidentate Ligands ◽  
Monodentate Ligand ◽  
Mononuclear Complexes ◽  
Monodentate Ligands

The chelate phosphanes Diphos, Diop, and Norphos were reacted with C5H5Mn(CO)2THF and CH3C5H4Mn(CO)2THF to give mononuclear complexes, containing the phosphanes as unidentate or as bidentate ligands, and dinuclear complexes, containing bridging phosphane ligands. In C5H5Mn(CO)2Diop one of the two P(C6H5)2 groups of Diop is coordinated to the C5H5Mn(CO)2 fragment; the uncoordinated P(C6H5)2 group makes it a monodentate ligand. C5H5Mn(CO)2Diop together with [Rh(cod)Cl]2 was used as an in situ catalyst in the enantioselective hydrogenation of (Z)-a-[N -acetam ino]cinnamic acid (78.4% ee) and in the enantioselective hydrosilylation of acetophenone with diphenylsilane (6.7% ee).

Synthesis of optically active functionalised cyclic ketimines and their application in enantioselective catalysis

2001 ◽  
Vol 12 (15) ◽  
pp. 2213-2222 ◽  
Author(s):  
Nikolai Graf v. Keyserlingk ◽  
Jürgen Martens
Keyword(s):  
Optically Active ◽  
Enantioselective Catalysis

Enantioselektive Katalyse, XVIII Der Einfluß nicht koordinierter Stereozentren auf die enantioselektive Hydrierung/Enantioselective Catalysis, XVIII The Influence of Non-Coordinated Stereocenters on the Enantioselective Hydrogenation

1998 ◽  
Vol 53 (2) ◽  
pp. 211-223 ◽  
Author(s):  
Ulrich Nagel ◽  
Christoph Roller
Keyword(s):  
Michael Addition ◽  
Enantioselective Hydrogenation ◽  
Palladium Complexes ◽  
Enantioselective Catalysis ◽  
Pyrrolidine Ring ◽  
Enantiomerically Pure ◽  
Stereogenic Centers ◽  
Methyl Phenyl ◽  
Phenyl Vinyl

Abstract 3,4-Bis{[2-(methyl-phenyl-oxophosphanyl)-ethyl]phenyl-phosphanyl}pyrrolidines have be­en synthesized by Michael Addition from the corresponding methyl-phenyl-vinyl-phosphane oxides and 3,4-bis(phenylphosphino)pyrrolidines. For purification of the ligands palladium complexes were used and with the enantiomerically pure ligands Rh complexes have been pre­pared. The catalyst has 6 stereogenic centers. In the hydrogenation of Z-α-acetamidocinnamic acid all six stereogenic centers have an influence on the enantioselectivity. The influence is strongest from the C stereocenters of the pyrrolidine ring. Less important are the stereogenic centers on the coordinated P atoms. The influence of the stereocenters on the non-coordinated P = O groups is the least, but it is not negligible. The ee values obtained with the ligands containing P = O groups are much lower than those obtained with ligands which are substituted only with aryl groups. Ketones are hydrogenated with only low ee’s.

ChemInform Abstract: Enantioselective Catalysis. Part 83. Synthesis of Optically Active Ferrocenylalanine.

ChemInform ◽  
2010 ◽  
Vol 24 (30) ◽  
pp. no-no
Author(s):  
H. BRUNNER ◽  
W. KOENIG ◽  
B. NUBER
Keyword(s):  
Optically Active ◽  
Enantioselective Catalysis

scholarly journals Synthesis of monomers for the preparation of optically active poly(amido–imide)s. Part 1. Synthesis of chiral imides containing a fragment of the natural amino acid based on nitrophenylcycloalkanedicarboxylic acids

2019 ◽  
Vol 57 (1) ◽  
pp. 27-40
Author(s):  
Anna A. Koverda ◽  
◽  
Alexandra I. Korshunova ◽  
Mikhail N. Koverda ◽  
Evgeny N. Sechin ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Amino Acid ◽  
Membrane Separation ◽  
Chloroform Solution ◽  
Dicarboxylic Acids ◽  
Optically Active ◽  
Alkylation Reaction ◽  
Catalytic Systems ◽  
Amino Acid Fragment ◽  
Acid Fragment

Previously it was shown that the stereochemical result of the alkylation reaction of benzene with cycloalkanedicarboxylic acids depends on the order of mixing the reagents. The resulting diastereomerically pure derivatives can be used as precursors of monomers for the synthesis of optically active poly(amido–imide)s, which are basic materials in chiral chromatographic separation. Their potential for use in chiral catalytic systems, liquid crystals in ferroelectric and nonlinear optics, in the manufacture of electrodes for enantioselective recognition during bioelectrosynthesis, membrane separation technology, etc. is shown. Nitration reactions of alkyl derivatives were carried out with their subsequent imidization with natural amino acids. The resulting diastereomerically pure dicarboxylic acids are nitrated with low selectivity, unlike their anhydrides, so the nitro derivatives were synthesized by nitrating the anhydrides with anhydrous nitric acid in chloroform solution. The racemization of the α-carbon center of the amino acid fragment occurs during the imidization reaction in glacial acetic acid. Using of DMF as a solvent under mild conditions is preferable, as it eliminates the possibility of racemization of the chiral center of the amino acid fragment. It was also found that during the preparation of imides, the configuration of the chiral centers of the cycloalkane dicarboxylic acid fragment is preserved. Nitrophenylnorbornanedicarboxylic acid forms an anhydride directly during synthesis in acetic acid, unlike cyclohexanedicarboxylic acids, due to its spatial structure. Nitrophenylnorbornanedicarboxylic acid is also characterized by easier imidization. The structure was determined using 1H, 13C NMR, 1H-1H NOESY, 1H-1H COSY, HPLC, capillary electrophoresis.

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