Copper-catalyzed stereo- and chemoselective synthesis of enaminones via Michael type addition

Regular Article


An efficient strategy for the synthesis of \(\upalpha \),\(\upbeta \)-unsaturated enaminones by the nucleophilic addition of N-heterocycles such as indole and imidazoles onto electronically bias alkynones under mild reaction conditions is described. Key feature of this reaction is the chemoselective addition of N-heterocycles onto ynones without affecting the \(1^{\mathrm{o}}\) amino groups (aromatic and aliphatic) of 5-aminoindole and tryptamine. The stereochemistry of the products was controlled by the tuning of reaction time. The mechanism of the reaction involves the Michael type addition of N-heterocycles on ynones via allene formation.

Graphical Abstract


Copper alkynones hydroamination Michael addition enaminones 



We gratefully acknowledge the Council of Scientific and Industrial Research, India [02(0264)/16/EMR-II] for financial support and USIC, University of Delhi for providing instrumentation facilities. M.P. and Sushmita are thankful to DST-SERB and UGC, New Delhi for fellowships.

Supplementary material

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Supplementary material 1 (pdf 3608 KB)


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Copyright information

© Indian Academy of Sciences 2018

Authors and Affiliations

  1. 1.Synthetic Organic Chemistry Research Laboratory, Department of ChemistryUniversity of DelhiDelhiIndia

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