Abstract
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).
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Sprecher, H., Payán, M.N.P., Weber, M. et al. Acyl Azide Synthesis and Curtius Rearrangements in Microstructured Flow Chemistry Systems. J Flow Chem 2, 20–23 (2012). https://doi.org/10.1556/jfchem.2011.00017
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DOI: https://doi.org/10.1556/jfchem.2011.00017