Synthesis 2012; 44(15): 2469-2473
DOI: 10.1055/s-0032-1316550
paper
© Georg Thieme Verlag Stuttgart · New York

Reductive Amination by Continuous-Flow Hydrogenation: Direct and Scalable Synthesis of a Benzylpiperazine

Jing Liu*
Janssen Research & Development, L.L.C., 3210 Merryfield Row, San Diego, CA 92121, USA, Fax: +1(858)3203354   Email: jliu30@its.jnj.com
,
Anne E. Fitzgerald
Janssen Research & Development, L.L.C., 3210 Merryfield Row, San Diego, CA 92121, USA, Fax: +1(858)3203354   Email: jliu30@its.jnj.com
,
Neelakandha S. Mani
Janssen Research & Development, L.L.C., 3210 Merryfield Row, San Diego, CA 92121, USA, Fax: +1(858)3203354   Email: jliu30@its.jnj.com
› Author Affiliations
Further Information

Publication History

Received: 19 March 2012

Accepted after revision: 18 May 2012

Publication Date:
02 July 2012 (online)


Abstract

A benzylpiperazine was prepared directly from the corresponding benzaldehyde and piperazine on a continuous-flow hydrogenation apparatus. The synthesis was protecting group free, safe, and environmentally friendly. Large-scale synthesis under flow hydrogenation conditions was also demonstrated.

Supporting Information

 
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  • 12 The price difference is on a per mole basis. From the same vendor (Sigma-Aldrich), N-Boc piperazine costs $335/25 g, or $2500/mol; piperazine costs $16/100 g, or $14/mol at the time the manuscript was written
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