Synlett 2021(18): 2708-2710  
DOI: 10.1055/s-0030-1259003
LETTER
© Georg Thieme Verlag Stuttgart ˙ New York

Towards a Practical Brønsted Acid Catalyzed and Hantzsch Ester Mediated Asymmetric Reductive Amination of Ketones with Benzylamine

Vijay N. Wakchaure, Marcello Nicoletti, Lars Ratjen, Benjamin List*
Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
Fax: +49(208)3062982; e-Mail: list@mpi-muelheim.mpg.de;
Further Information

Publication History

Received 24 August 2010
Publication Date:
14 October 2010 (online)

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Abstract

We report the use of benzylamine as the amine component in Hantzsch ester mediated and chiral Brønsted acid catalyzed enantioselective reductive aminations of ketones. The method is noteworthy because the benzyl group is easily removable, and amine product purification is achieved through Hantzsch ester oxidation product removal via basic hydrolysis.

Key words

benzylamine - Hantzsch ester - reductive amination - ­organocatalysis - chiral amines - Brønsted acids

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8

The absolute configuration of amine 5a was established via comparing the HPLC chromatogram with authentic sample of (S)-5a.