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Updated: Aug 23, 2025

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Heteroarylation of unactivated C-H bonds suitable for late-stage functionalization
Austin S Miller1, Erik J Alexanian1
1Department of Chemistry, The University of North Carolina at Chapel Hill Chapel Hill North Carolina 27599 USA eja@email.unc.edu.
Abstract:
The late-stage introduction of diverse heterocycles onto complex small molecules enables efficient access to new medicinally relevant compounds. An attractive approach to such a transformation would utilize the ubiquitous aliphatic C-H bonds of a complex substrate. Herein, we report a system that enables direct C-H heteroarylation using a stable, commercially available O-alkenylhydroxamate with heterocyclic sulfone partners. The C-H heteroarylation proceeds efficiently with a range of aliphatic substrates and common heterocycles, and is a rare example of heteroarylation of strong C-H bonds. Importantly, the present approach is amenable to late-stage functionalization as the substrate is the limiting reagent in all cases.
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