Synthesis 2020; 52(22): 3389-3396
DOI: 10.1055/s-0040-1707339
special topic
© Georg Thieme Verlag Stuttgart · New York

Intensification of Free-Radical Racemization for a Non-activated Amine in a Continuous Flow Reactor

Frédéric C. Toussaint
UCB Pharma S.A., Avenue de l’Industrie 1, 1420 Braine-l’Alleud, Belgium   Email: frederic.toussaint@ucb.com   Email: thierry.defrance@ucb.com
,
Thierry Defrance
UCB Pharma S.A., Avenue de l’Industrie 1, 1420 Braine-l’Alleud, Belgium   Email: frederic.toussaint@ucb.com   Email: thierry.defrance@ucb.com
,
Serge Decouvreur
,
Nicolas Carly
,
Alain Merschaert
› Author Affiliations
Further Information

Publication History

Received: 04 May 2020

Accepted after revision: 26 May 2020

Publication Date:
07 July 2020 (online)


Published as part of the Special Topic Synthesis in Industry

Abstract

The free-radical racemization of non-activated amines is a powerful tool for process design in the pharmaceutical industry, allowing the recycling of undesired enantiomers after chiral separation. This paper describes the development of the free-radical racemization of a key API intermediate in a continuous flow reactor. Upon development, a significant reduction of the solvent usage and radical initiator was made possible thanks to the conversion into a continuous flow mode. This intensification positively impacted both the environmental footprint and the safety of the reaction as well as maintaining satisfactory productivity.

 
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