Synthesis 2009(12): 2113-2115  
DOI: 10.1055/s-0029-1216804
PSP
© Georg Thieme Verlag Stuttgart ˙ New York

A Simplified Synthesis of Takemoto’s Catalyst

A. Berkessel*, B. Seelig
University of Cologne, Department of Chemistry, Greinstr. 4, 50939 Cologne, Germany
Fax: +49(221)4705102; e-Mail: [email protected];
Further Information

Publication History

Received 16 March 2009
Publication Date:
12 May 2009 (online)

Abstract

A facile two-step procedure for the preparation of Takemoto’s catalyst is reported. The thiourea moiety was obtained by condensation of 3,5-bis(trifluoromethyl)aniline with phenyl chlorothioformate and in situ substitution of phenol by trans-1,2-diaminocyclohexane. Subsequent reductive dimethylation using formaldehyde/zinc afforded Takemoto’s catalyst.

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