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Updated: Jun 24, 2026

Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions
Published on: November 30, 2022
Rh(I)-catalyzed CO gas-free carbonylative cyclization reactions of alkynes with 2-bromophenylboronic acids using
Tsumoru Morimoto1, Kae Yamasaki, Akihisa Hirano
1Graduate School of Materials Science, Nara Institute of Science and Technology (NAIST), Takayama, Ikoma, Nara 630-0192, Japan.
Abstract:
The rhodium(I)-catalyzed reaction of alkynes with 2-bromophenylboronic acids in the presence of paraformaldehyde resulted in a CO gas-free carbonylative cyclization, yielding indenone derivatives. [RhCl(BINAP)](2) and [RhCl(cod)](2) were responsible for the decarbonylation of formaldehyde and the subsequent carbonylation of alkynes with 2-haloboronic acids, respectively, leading to efficient whole carbonylation. Sterically bulky and electron-withdrawing groups on unsymmetrically substituted alkynes favored the alpha-position of indenones.
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