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Bitterfeld-Wolfen, Germany

Luhr S.,Leibniz Institute for Catalysis at the University of Rostock | Holz J.,Leibniz Institute for Catalysis at the University of Rostock | Zayas O.,Leibniz Institute for Catalysis at the University of Rostock | Wendisch V.,ChiroBlock GmbH andresenstrasse 1a | And 2 more authors.
Tetrahedron Asymmetry | Year: 2012

The synthesis of chiral β 2-amino acids by homogeneous asymmetric hydrogenation is discussed. Prochiral β-aryl- or β-hetaryl-α-N-benzyl/N-acetyl/N-Boc substituted α- aminomethylacrylates used as substrates were prepared by a Baylis-Hillman reaction, followed by acylation and amination. For the asymmetric hydrogenation, a large variety of chiral, preferentially rhodium catalysts bearing commercially available phosphorus ligands were tested. Conversions and enantioselectivities were dependent on the reaction conditions and varied strongly between the substrates used. A chiral N-α-phenylethyl group supports the stereoface discriminating ability of the chiral catalysts and thus a matching pair effect could be realized. In strong contrast, a chiral ester group has almost no effect in this respect. In some cases the use of the corresponding substrate acid was better in comparison to the use of its ester. After optimization of the hydrogenation conditions (chiral catalyst, H 2-pressure, temperature, solvent), full conversions and products with up to 99% ee were achieved.© 2012 Elsevier Ltd. All rights reserved.


The foundation of an own company constitutes a promising professional alternative for chemists. Both, the global economic trends and the specific features of the chemical industry fuel the process of generating the majority of new chemistry jobs in such start-up companies. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Luhr S.,Leibniz Institute for Catalysis at the University of Rostock | Holz J.,Leibniz Institute for Catalysis at the University of Rostock | Zayas O.,University of Rostock | Seidelmann O.,ChiroBlock GmbH andresenstrasse 1a | And 3 more authors.
Tetrahedron Asymmetry | Year: 2013

The stereoselective synthesis of chiral β2-homoalanine derivatives with 99% ee by the Rh-catalyzed enantioselective hydrogenation of prochiral 2-aminomethyl acrylates is described. The subsequent transformation to chiral 3-amino-2-methylpropanols is also demonstrated. © 2013 Elsevier Ltd. All rights reserved.


Petri A.,ChiroBlock GmbH andresenstrasse 1a | Seidelmann O.,ChiroBlock GmbH andresenstrasse 1a | Eilitz U.,ChiroBlock GmbH andresenstrasse 1a | Lessmann F.,ChiroBlock GmbH andresenstrasse 1a | And 3 more authors.
Tetrahedron Letters | Year: 2014

Asymmetric conjugate addition of arylboronic acids to 2-nitroacrylamide in the presence of cationic palladium-Chiraphos complex proceeds with high yield and enantioselectivity (73-89% ee) using as low as 0.05-0.25 mol % of the catalyst. The adducts can be smoothly transformed into the corresponding β2-homophenylglycines in two simple steps. © 2013 Elsevier Ltd. All rights reserved.

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