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Updated: May 11, 2026

Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions
Published on: November 30, 2022
Iridium-catalyzed borylation of secondary benzylic C-H bonds directed by a hydrosilane
Seung Hwan Cho1, John F Hartwig
1Department of Chemistry, University of California, Berkeley , California 94270, United States.
Abstract:
Most functionalizations of C-H bonds by main-group reagents occur at aryl or methyl groups. We describe a highly regioselective borylation of secondary benzylic C-H bonds catalyzed by an iridium precursor and 3,4,7,8-tetramethyl-1,10-phenanthroline as the ligand. The reaction is directed to the benzylic position by a hydrosilyl substituent. This hydrosilyl directing group is readily deprotected or transformed to other functional groups after the borylation reaction, providing access to a diverse set of secondary benzylboronate esters by C-H borylation chemistry.
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