Journal of Flow Chemistry

, Volume 2, Issue 1, pp 20–23 | Cite as

Acyl Azide Synthesis and Curtius Rearrangements in Microstructured Flow Chemistry Systems

  • Hanspeter Sprecher
  • M. Nieves Pérez Payán
  • Michael Weber
  • Goekcen Yilmaz
  • Gregor Wille
Full Paper


The synthesis and utilisation of acyl azides in a flow apparatus combined with an automated extraction unit is described. This process safely provides multi-100 g quantities of a labile diacyl azide (3) as an intermediate that could not be generated safely by classic batch methods. Its subsequent conversion to the desired amine (4) represents an example for process intensification. The same set-up with an output capacity of >30 g/h was used for the unattended synthesis of benzoyl azide as the final product in solution (tert-butyl methyl ether (TBME), 0.5 M).


acyl azide synthesis Curtius rearrangement continuous extraction process safety 


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Copyright information

© Akadémiai Kiadó 2011

Authors and Affiliations

  • Hanspeter Sprecher
    • 1
  • M. Nieves Pérez Payán
    • 1
  • Michael Weber
    • 1
  • Goekcen Yilmaz
    • 1
  • Gregor Wille
    • 1
  1. 1.Sigma-Aldrich Production GmbHBuchsSwitzerland

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