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Updated: Oct 4, 2025

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Remote steric control for undirected meta-selective C-H activation of arenes
Boobalan Ramadoss1, Yushu Jin1, Sobi Asako1
1RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Abstract:
Regioselective functionalization of arenes remains a challenging problem in organic synthesis. Steric interactions are often used to block sites adjacent to a given substituent, but they do not distinguish the remaining remote sites. We report a strategy based on remote steric control, whereby a roof-like ligand protects the distant para site in addition to the ortho sites, and thereby enables selective activation of meta carbon-hydrogen (C-H) bonds in the absence of ortho or para substituents. We demonstrate this concept for iridium-catalyzed meta-selective borylation of various monosubstituted arenes, including complex drug molecules. This strategy has the potential to expand the toolbox of C-H bond functionalization to previously nondifferentiable reaction sites.
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