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Acknowledgements
The authors thank M. Simonetti and F. Juliá-Hernandez for useful discussions.
D.L. thanks EPSRC for a Fellowship (EP/P004997/1) and the European Research
Council for a research grant (758427). A.R. thanks the Marie Curie Actions for a
Fellowship (703238).
Author contributions
A.R., F.J. and D.L. designed the project. A.R., F.J., T.D.S. and A.J.M. performed all the
synthetic experiments. J.J.D. performed the batch-to-flow optimization and scale-up. All
authors analysed the results and wrote the manuscript.
Competing interests
The authors declare no competing interests.
Additional information
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Correspondence and requests for materials should be addressed to D.L.
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