Iridium-Catalyzed Site-Selective C–H Borylation of 2-Pyridones

Published as part of the Special Topic Modern Strategies for Borylation in Synthesis

Abstract

An iridium-catalyzed site-selective C–H borylation of 2-pyridones has been developed. The site selectivity is predominantly controlled by steric factors, and we can access C4, C5, and C6 C–H on the 2-pyridone ring by the judicious choice of ligand and solvent. Subsequent Suzuki–Miyaura cross-coupling of the borylated products also proceeds to form the corresponding arylated pyridones in good overall yields.

Key words

borylation - C–H functionalization - iridium - 2-pyridones - site selectivity

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