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ChemComm
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DOI: 10.1039/C7CC09491D
COMMUNICATION
Journal Name
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a plausible reaction 4. M. Hashimoto, Y. Obora, S. Sakaguchi and Y. Ishii, J. Org.
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activates the hydroxyl moiety of the oxime which produces 5. R. S. Ramón, J. Bosson, S. Díez-González, N. Marion and S. P.
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to form intermediate 3a, and following loss of the amide, the 6. S. Chandrasekhar and K. Gopalaiah, Tetrahedron Lett., 2003,
active calcium species is regenerated through recomplexation 44, 755-756.
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Figure 1. Plausible Catalytic Pathway
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In conclusion we have developed a mild, catalytic Beckmann
rearrangement employing a calcium (II) catalyst. Our system is
tolerant of a range of functionalities pertinent to natural
product synthesis and medicinal chemistry, as well as allowing
the use of acid labile moieties. The synthentic utility of the
reaction has been demonstrated, and we show that the
reaction is ammenable to one pot. We propose a plausible
mechanism based on preliminary investigations, with further
detailed studies underway.
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The SGC is a registered charity (number 1097737) that receives
funds from AbbVie, Bayer, Boehringer Ingelheim, the Canada
Foundation for Innovation, the Canadian Institutes for Health
Research, Genome Canada, GlaxoSmithKline, Janssen, Lilly
Canada, the Novartis Research Foundation, the Ontario
Ministry of Economic Development and Innovation, Pfizer,
Takeda, and the Wellcome Trust [092809/Z/10/Z]. MGM
wishes to thank MMU for startup funding.
Tsubogo, Y. Yamashita and S. Kobayashi, Top. Catal., 2014, 57
,
935-939.
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and S. France, Tetrahedron, 2017, 73, 4093; (b) M. J. Sandridge
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Conflicts of interest
There are no conflicts to declare.
19. (a) B.-X. Tian, N. An, W.-P. Deng and L. A. Eriksson, J. Org.
Chem., 2013, 78, 6782-6785; (b) R. Akimoto, T. Tokugawa, Y.
Yamamoto and H. Yamataka, J. Org. Chem., 2012, 77, 4073-
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Notes and references
1. (a) R. E. Gawley, in Organic Reactions, John Wiley & Sons,
Inc., 1988, vol. 35, p. 1; (b) Shin, D. J. Jung and S.-g. Lee, ACS
Catalysis, 2013, 3, 525-528.
4 | J. Name., 2012, 00, 1-3
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