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Updated: Jul 20, 2025

Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions
Published on: November 30, 2022
Metal-Free Directed Site-Selective Csp3 -H Borylation of Saturated Cyclic Amines
Puneeth Kumar Someswara Ashwathappa1, Takuya Higashi2, Vincent Desrosiers1
1Département de Chimie, Université Laval, 1045 Avenue de la Médecine, Québec, Québec G1 V 0 A6, Canada.
Abstract:
The borylation of Csp3 -H bonds is a challenging transformation that is typically restricted to transition metal catalysis. Herein, we report the site-selective metal-free Csp3 -H borylation of saturated cyclic amines. It is possible to selectively borylate piperidine derivatives at the α or β positions according to the reaction conditions. The mechanism was supported by NMR spectroscopy, calorimetry experiments and density functional theory (DFT) computations. It suggests that the piperidine is dehydrogenated by complexation with BBr3 to produce an enamine intermediate, which is in turn borylated at either the α or β position according to the reaction conditions.
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