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Updated: Dec 24, 2025
A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Sterically Controlled C-H Olefination of Heteroarenes
Hao Chen1, Mirxan Farizyan1, Francesca Ghiringhelli2
1Max Planck Institute for Chemical Energy Conversion, Stiftstraße 34-36, 45470, Mülheim an der Ruhr, Germany.
Abstract:
The regioselective functionalization of heteroarenes is a highly attractive synthetic target due to the prevalence of multiply substituted heteroarenes in nature and bioactive compounds. Some substitution patterns remain challenging: While highly efficient methods for the C2-selective olefination of 3-substituted five-membered heteroarenes have been reported, analogous methods to access the 5-olefinated products have remained limited by poor regioselectivities and/or the requirement to use an excess of the valuable heteroarene starting material. Herein we report a sterically controlled C-H olefination using heteroarenes as the limiting reagent. The method enables the highly C5-selective olefination of a wide range of heteroarenes and is shown to be useful in the context of late-stage functionalization.
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