Paper
RSC Advances
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Conclusions
In summary, we have developed four methodologies for the
regioselective synthesis of polyfunctionalized isoxazoles by
cyclocondensation of b-enamino diketones with hydroxyl-
amine. The regiochemistry of the reaction has been controlled
by: the solvent; use of pyridine; the Lewis acid carbonyl acti-
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Conflicts of interest
There are no conicts to declare.
Acknowledgements
The authors are grateful for the nancial support from CNPq/
Brazil (CNPq/Universal Process No. 45920/2014-8) and
˜
´
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