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C-H Borylation Catalysts that Distinguish Between Similarly Sized Substituents Like Fluorine and Hydrogen.

ABSTRACT: By modifying ligand steric and electronic profiles it is possible to C-H borylate ortho or meta to substituents in aromatic and heteroaromatic compounds, where steric differences between accessible C-H sites are small. Dramatic effects on selectivities between reactions using B₂pin₂ or 4,4,5,5-tetramethyl-1,3,2-dioxaborolane (HBpin) are described for the first time. Judicious ligand and borane combinations give highly regioselective C-H borylations on substrates where typical borylation protocols afford poor selectivities.

SUBMITTER: Miller SL

PROVIDER: S-EPMC9864527 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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C-H Borylation Catalysts that Distinguish Between Similarly Sized Substituents Like Fluorine and Hydrogen.

Miller Susanne L SL Chotana Ghayoor A GA Fritz Jonathan A JA Chattopadhyay Buddhadeb B Maleczka Robert E RE Smith Milton R MR

Organic letters 20190808 16

By modifying ligand steric and electronic profiles it is possible to C-H borylate ortho or meta to substituents in aromatic and heteroaromatic compounds, where steric differences between accessible C-H sites are small. Dramatic effects on selectivities between reactions using B<sub>2</sub>pin<sub>2</sub> or 4,4,5,5-tetramethyl-1,3,2-dioxaborolane (HBpin) are described for the first time. Judicious ligand and borane combinations give highly regioselective C-H borylations on substrates where typic ...[more]

PMID: 31393137

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