Edge Article
Chemical Science
reductant under very mild conditions (room temperature). The
reaction produces only traceless non-toxic N2 and H2 gases as by-
products. The protocol solves the long-standing metal waste
issues in the classical pinacol coupling reactions and has a rela-
tively broad aromatic ketone scope and functional group toler-
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Conflicts of interest
There are no conicts to declare.
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Acknowledgements
We are grateful to the Canada Research Chair Foundation (to C.- 14 D. Cao, C. Yan, P. Zhou, H. Zeng and C. J. Li, Chem.
J. Li), the CFI, FRQNT Center for Green Chemistry and Catalysis, Commun., 2019, 55, 767–770.
NSERC, and McGill University for support of our research. R. Z. 15 (a) S. Hunig, H. R. Muller and W. Thier, Angew. Chem., Int.
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K. acknowledges funding by NSERC through the Discovery
Grant (RGPIN-2016-05059). The authors are grateful to
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Compute Canada for computer time and thank Siting Ni for 16 (a) D. Leow, Y. H. Chen, T. H. Hung, Y. Su and Y. Z. Lin, Eur.
assistance with UV-visible and uorescence spectra measure-
ments. Z. Qiu is grateful to McGill's Chemistry Department for
the Major Scholarship and Pall Dissertation Award. D. Castillo-
J. Org. Chem., 2014, 2014, 7347–7352; (b) B. Pieber,
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Pazos thanks CONACYT Mexico (2018-000009-01EXTF-00413) 17 B. N. Kenessov, J. A. Koziel, T. Grotenhuis and L. Carlsen,
for nancial support.
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25 The corresponding ketyl radical TEMPO and BHT adducts
could be detected in trace amounts by ESI-HRMS. For
TEMPO, HRMS (ESI): found for the adduct C22H29O2NNa
([M + Na]+) 362.2104, calculated 362.2091; for BHT, HRMS
(ESI): found for the adduct C28H34O2Na ([M + Na]+)
425.2466, calculated 425.2451.
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