Communication
ChemComm
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Fig. 1 Scale-out processing of the developed protocol. Assay yields were
determined by 19F NMR integration. (a) Reaction conditions used. (b) Product
profile over time, using conditions in blue (high photocatalyst loading, short
residence time). (c) Product profile over time, using conditions in red (low
photocatalyst loading, long residence time).
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10 A. Wimmer and B. Konig, Org. Lett., 2019, 21, 2740–2744.
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In summary, we present the first nickel/photoredox methodol-
ogy for the formation of arylhydrazine derivatives. This methodol-
ogy was rapidly optimized in continuous flow, using a combination
of one factor at a time and DoE experiments, providing an in-depth
understanding of the influence of each reaction variable. The
optimized conditions were found to be applicable to a range of
aryl halide substrates, including N-heterocycles and some aryl
chlorides. Finally, a scale-out experiment demonstrated the issues
of Ni(0) formation over time, but this could be minimized using
altered reaction conditions for more stable processing.
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J. P. McMullen, F. Levesque, M. K. Wismer and J. R. Naber,
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Conflicts of interest
There are no conflicts to declare.
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same reactor, see: (a) C. Rosso, J. D. Williams, G. Filippini, M. Prato
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Chem. Commun.
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