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Updated: May 27, 2025

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Hydrogen-Bonding Network-Enabled Terminal Selective Heteroarylation of Allenamides in Hexafluoroisopropanol
Sachin Balaso Mohite1, Partha Sarathi Bera2, Yafia Kousin Mirza2
1Department of Pharmaceutical Chemistry, Discipline of Pharmaceutical Sciences, College of Health Sciences, University of KwaZulu-Natal (Westville), Durban 4000, South Africa.
Abstract:
Hexafluoroisopropanol (HFIP)-mediated terminal selective heteroarylation of allenamides has been accomplished through H-bonding network-enabled substrate activation in a robust fashion. This strategy features a cascade process involving sequential nucleophilic addition followed by electrophilic heteroaromatic substitution and is well suited for late-stage functionalization of complex bioactive molecules. The elucidation of the underlying mechanism was achieved through a comprehensive combination of several control experiments, kinetic studies, isotopic labeling experiments, and the isolation of the HFIP-allenamide intermediate adduct.
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