Check out this featured article as part of the upcoming Special Issue on Enabling Technologies for Organic Synthesis in J Org Chem/Org Letters:
Exploiting Continuous Processing for Challenging Diazo Transfer and Telescoped Copper-Catalyzed Asymmetric Transformations. Daniel C. Crowley; Thomas A. Brouder; Aoife M. Kearney; Denis Lynch; Alan Ford; Stuart G. Collins and Anita R. Maguire at University College Cork
All the power of diazo chemistry with none of the hazard – the team has shown that the very powerful enantioselective chemistry which can be achieved using diazo compounds and copper catalysts can be conducted in continuous flow – right from the preparation of the sulfonyl azide precursor, the diazo transfer and the enantioselective copper-catalysed carbon carbon bond forming step.
The real challenge here is getting the reaction stream clean enough to avoid destroying the copper catalyst at the end of the chain – we cracked this problem with the help of a very talented bunch of PhD students and post-docs.