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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Cobalt(III)-Catalyzed [4 + 2] Annulation of N-Chlorobenzamides with Maleimides
Nachimuthu Muniraj1, Kandikere Ramaiah Prabhu1
1Department of Organic Chemistry , Indian Institute of Science , Bangalore 560 012 , Karnataka , India.
Abstract:
A Co(III)-catalyzed novel [4 + 2] annulation of N-chlorobenzamides with maleimides has been reported. Mostly, maleimides are known to furnish the Michael-type or 1,1-type cyclized products while treating with amides. In this reaction, maleimides furnished [4 + 2] annulated products in good yields at room temperature while being treated with the internal oxidizing N-chlorobenzamide as a directing group. The developed methodology is compatible with a variety of functional groups. The [4 + 2] annulated products obtained are featured in some biologically active molecules.
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