10.1002/cctc.202000597
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In conclusion, we have presented the selective isomerization of a
series of terminal aziridines to yield the desired enamides using
the highly reactive nucleophilic rhodium catalyst
C under
moderate conditions. Most of the tested aziridines were converted
smoothly with only 1 mol% catalyst loading and excellent yields
were obtained. Intermediates containing the terminal C=C double
bond were detected during the course of the reaction with
substrates containing an electron poor group. The double bond
migrates to the internal C=C double bond to complete the reaction.
Based on these observations, a dual-activation mechanism
including the activation of the substrate by the Lewis acid and the
nucleophilic opening by Rh catalyst is proposed. This novel
transformation provides an alternative strategy for the synthesis
of enamides.
Acknowledgements
Yingying Tian thanks the China Scholarship Council (CSC) for a
predoctoral fellowship. We are grateful to Xiaoli Su, Jan Grammel
and Christina Breitenstein for their help with some substrate
synthesis.
Keywords: enamides • isomerization • rhodium • terminal
aziridines • thermodynamics
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