Practical synthesis of isocoumarins via Rh(III)-catalyzed C-H activation/annulation cascade.

Beilstein J Org Chem

Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science, School of Chemistry and Materials Science, South-Central Minzu University, Wuhan 430074, People's Republic of China.

Published: January 2023

Herein, we report an unprecedented Rh(III)-catalyzed C-H activation/annulation cascade of readily available enaminones with iodonium ylides towards the convenient synthesis of isocoumarins. This coupling system proceeds in useful chemical yields (up to 93%) via a cascade C-H activation, Rh-carbenoid migratory insertion and acid-promoted intramolecular annulation. The success of gram-scale reaction and diverse functionalization of isocoumarins demonstrated the synthetic utility of this protocol.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9907013PMC
http://dx.doi.org/10.3762/bjoc.19.10DOI Listing

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