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ChemComm
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COMMUNICATION
Journal Name
In summary, we have developed a unique approach for the 8 R. Slade, Y. Klimova, R. Halter, A. Yungai, W. Weiner, R. Walton, J.
DOI: 10.1039/C9CC00943D
synthesis of various 1,2-diarylindoles from cyclohexanones, α-
hydroxy ketones and anilines under transition-metal-free conditions.
Willardsen, M. Anderson and K. Zavitz, US 20080249135 A1, 2008-
10-09, 2008.
Cyclohexanones were employed as the aryl sources under aerobic 9 P. Rhonnstad, E. Kallin, T. Apelqvist, M. Wennerstal and A.
conditions without the aid of transition-metal catalyst. Secondary Cheng, WO 2009127686 A1, 2009-10-22, 2009.
amines acted as the efficient organic catalyst in this kind of 10 J. McCall, D. Romero, M. Clare, US 20120225846 A1, 2012-09-06,
transformation. The present method showed great advantages in the 2012.
synthesis of two bioactive 1,2-diaryindole derivatives using readily 11 (a) L. Kaspar and L. Ackermann, Tetrahedron, 2005, 61, 11311; (b)
available starting materials and less synthetic steps. This method can
completely avoid transition-metal pollution which is very important
factor for bioactive molecule synthesis. Further applications of this
methodology for the synthesis of valuable indole-based compounds
are in progress.
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Acknowledgements
This work was supported by the National Natural Science
Foundation of China (21871226, 21572194), the China Postdoctoral
Science Foundation (2018M632976) and the Hunan Provincial
Natural Science Foundation of China (2019JJ50102).
Conflicts of interest
There are no conflicts to declare.
14 For selected examples of C-2 arylation of N-aryl indoles (no
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Notes and references
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4 | J. Name., 2012, 00, 1-3
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