Palladium-Catalyzed C7–H (Hetero)arylation of Pyrazolo[1,5-a]pyrazines with Heteroarenes and Aryl Iodides with the Assistance of Silver Salts

Abstract

Pyrazolo[1,5-a]pyrazines coupled with heteroarenes and aryl iodides selectively at the C7 position to afford a broad library of bi(hetero)aryl structures under ligand-free palladium-catalyzed conditions. The key to the success of the reaction is the use of silver salts as the oxidant or the base, allowing the regioselective C–H bond functionalization to occur under relatively mild conditions.

Key words

C–H bond functionalization - fused-ring systems - heteroarenes - homogeneous catalysis - synthetic methods

Publikationsverlauf

Eingereicht: 13. Dezember 2022

Angenommen nach Revision: 30. Januar 2023

Artikel online veröffentlicht:
06. März 2023

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