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Updated: Apr 12, 2026
Synthesis of a Borylated Ibuprofen Derivative Through Suzuki Cross-Coupling and Alkene Boracarboxylation Reactions
Published on: November 30, 2022
Catalyst-controlled regiodivergent C-H borylation of multifunctionalized heteroarenes by using iridium complexes
Ikuo Sasaki1, Jumpei Taguchi1, Shotaro Hiraki1
1Division of Chemical Process Engineering and Frontier Chemistry Center (FCC), Graduate School of Engineering, Hokkaido University, Kita 13 Nishi 8 Kita-ku, Sapporo, Hokkaido 060-8628 (Japan), Fax: (+81) 117066562.
Abstract:
The regiodivergent C-H borylation of 2,5-disubstituted heteroarenes with bis(pinacolato)diboron was achieved by using iridium catalysts formed in situ from [Ir(OMe)(cod)]2 /dtbpy (cod=1,5-cyclooctadiene, dtbpy: 4,4'-di-tert-butyl-2,2'-bipyridine) or [Ir(OMe)(cod)]2 /2 AsPh3 . When [Ir(OMe)(cod)]2 /dtbpy was used as the catalyst, borylation at the 4-position proceeded selectively to afford 4-borylated products in high yields (dtbpy system A). The regioselectivity changed when the [Ir(OMe)(cod)]2 /2 AsPh3 catalyst was used; 3-borylated products were obtained in high yields with high regioselectivity (AsPh3 system B). The regioselectivity of borylation was easily controlled by changing the ligands. This reaction was used in the syntheses of two different bioactive compound analogues by using the same starting material.
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