Organic Letters
Letter
Sahoo, M. K.; Landge, V. G.; Rajamohanan, P. R.; Balaraman, E. Nat.
Commun. 2015, 6, 8591.
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homogeneous Lewis acid catalysis. Moreover, under mild
reaction conditions, a wide range of alkynes and anilines with
different electronic and steric properties are tolerated. Thus,
the newly developed procedure competes favorably with
different reports in the literature, which mostly require elevated
temperatures and display a more narrow substrate scope. By
using 2,6-tert-butylpyridine as a proton scavenger, we
confirmed that Mg(NTf2)2 acts as a Lewis acid catalyst for
our transformation. Furthermore, by means of D-labeling
experiments, we obtained a deeper inside into the mechanism
of the transformation that helped to explain the new
magnesium catalysis.
ASSOCIATED CONTENT
* Supporting Information
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S
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The Supporting Information is available free of charge on the
́
(10) (a) Begue, J.-P.; Bonnet-Delpon, D.; Crousse, B. Synlett 2004,
Detailed characterization of products and 1H and
18. (b) Sugiishi, T.; Matsugi, M.; Hamamoto, H.; Amii, H. RSC Adv.
2015, 5, 17269. (c) Colomer, I.; Chamberlain, A. E. R.; Haughey, M.
B.; Donohoe, T. J. Nat. Rev. Chem. 2017, 1, 88.
(11) For representative examples in the use of nBu4NPF6 for
enhancing catalytic activities of Lewis acids, see: (a) Haubenreisser,
S.; Niggemann, M. Adv. Synth. Catal. 2011, 353, 469. (b) Davies, J.;
Leonori, D. Chem. Commun. 2014, 50, 15171. (c) Qi, C.; Hasenmaile,
F.; Gandon, V.; Lebœuf, D. ACS Catal. 2018, 8, 1734.
AUTHOR INFORMATION
Corresponding Authors
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ORCID
(12) For recent examples of improvement of catalytic activity using
HFIP, see: (a) Berkessel, A.; Adrio, J. A.; Huttenhain, D.; Neudorfl, J.
̈
̈
M. J. Am. Chem. Soc. 2006, 128, 8421. (b) Berkessel, A.; Adrio, J. A. J.
Am. Chem. Soc. 2006, 128, 13412. (c) Motiwala, H. F.; Fehl, C.; Li, S.-
Notes
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W.; Hirt, E.; Porubsky, P.; Aube, J. J. Am. Chem. Soc. 2013, 135, 9000.
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(d) Vekariya, R. H.; Aube, J. Org. Lett. 2016, 18, 3534. (e) Zeng, X.;
Liu, S.; Shi, Z.; Xu, B. Org. Lett. 2016, 18, 4770. (f) Kamitanaka, T.;
Morimoto, K.; Tsuboshima, K.; Koseki, D.; Takamuro, H.; Dohi, T.;
Kita, Y. Angew. Chem., Int. Ed. 2016, 55, 15535. (g) Colomer, I.;
Batchelor-McAuley, C.; Odell, B.; Donohoe, T. J.; Compton, R. G. J.
Am. Chem. Soc. 2016, 138, 8855. (h) Vukovic, V. D.; Richmond, E.;
Wolf, E.; Moran, J. Angew. Chem., Int. Ed. 2017, 56, 3085. (i) Ref 11c.
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(15) Earle, M. J.; Hakala, U.; McAuley, B. J.; Nieuwenhuyzen, M.;
Ramani, A.; Seddon, K. R. Chem. Commun. 2004, 0, 1368.
(16) During the preparation of the manuscript, Gandon and Leboeuf
reported a Ca(NTf2)2:nBuNPF6-catalyzed hydroarylation of electron
deficient styrenes using HFIP as a solvent: Qi, C.; Gandon, V.;
Leboeuf, D. Angew. Chem., Int. Ed. 2018, 57, 14245.
The authors declare no competing financial interest.
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