Organic Letters
Letter
(3) For general reviews of NHC chemistry, see: (a) Mahatthananchai,
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(4) For reviews of oxidative NHC-mediated reactions, see: (a) De
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Lett. 2014, 16, 1928.
(7) For reviews of flow electrochemistry, see: (a) Watts, K.; Baker,
A.; Wirth, T. J. Flow Chem. 2014, 4, 2. (b) Yoshida, J.-i.; Nagaki, A.
Electrochemical Reactions in Microreactors. In Microreactors in
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(8) For a description of the cell used in this work, see: (a) Kuleshova,
J.; Hill-Cousins, J. T.; Birkin, P. R.; Brown, R. C. D.; Pletcher, D.;
Underwood, T. J. Electrochim. Acta 2012, 69, 197. For examples of
electrosyntheses in the cell, see: (b) Hill-Cousins, J. T.; Kuleshova, J.;
Green, R. A.; Birkin, P. R.; Pletcher, D.; Underwood, T. J.; Leach, S.
G.; Brown, R. C. D. ChemSusChem 2012, 5, 326. (c) Green, R. A.;
Hill-Cousins, J. T.; Brown, R. C. D.; Pletcher, D.; Leach, S. G.
Electrochim. Acta 2013, 113, 550.
(9) A closely related cell is available commercially and has been
applied by others in electrosyntheses. For examples, see: (a) Roth, G.;
Stalder, R.; Long, T.; Sauer, D.; Djuric, S. J. Flow Chem. 2013, 3, 34.
(b) Stalder, R.; Roth, G. P. ACS Med. Chem. Lett. 2013, 4, 1119.
(c) Kabeshov, M. A.; Musio, B.; Murray, P. R. D.; Browne, D. L.; Ley,
S. V. Org. Lett. 2014, 16, 4618.
(10) The cell current varied during the course of the experiment: at
the start of the run, the current increased from 0 to 850 mA as the
channel filled with electroactive species, and then it decreased at the
end of the run as the channel refilled with solvent. At steady state, the
cell current was 850 mA.
(11) For details of the design of experiment, see the Supporting
Information.
(12) (a) Nakanishi, I.; Itoh, S.; Fukuzumi, S. Chem.Eur. J. 1999, 5,
2810. (b) Barletta, G.; Chung, A. C.; Rios, C. B.; Jordan, F.; Schlegel, J.
M. J. Am. Chem. Soc. 1990, 112, 8144.
(13) Green, R. A.; Brown, R. C. D.; Pletcher, D. J. Flow Chem. 2015,
5, 31.
(14) The mass transport characteristics of the electrochemical flow
cell are described in ref 8a.
D
Org. Lett. XXXX, XXX, XXX−XXX