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Updated: Jun 19, 2026
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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
The first transannular [4+3] cycloaddition reaction: synthesis of the ABCD ring structure of cortistatins
Derek T Craft1, Benjamin W Gung
1Department of Chemistry and Biochemistry, Miami University Oxford, OH 45056.
Abstract:
A 14-membered macrocycle with an allene and a furan strategically located at across the ring from each other is synthesized using an allene ring closing metathesis reaction. Upon treatment of the macrocycle with a catalytic amount of Pd(OAc)(2) and other additives, the first transannular [4+3] cycloaddition occurred to yield 37% of a tetracyclic compound containing the ABC ring structure of the natural products cortistatins.
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