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Hydrogen Bond Directed ortho-Selective C-H Borylation of Secondary Aromatic Amides.

ABSTRACT: Reported is an iridium catalyst for ortho-selective C-H borylation of challenging secondary aromatic amide substrates, and the regioselectivity is controlled by hydrogen-bond interactions. The BAIPy-Ir catalyst forms three hydrogen bonds with the substrate during the crucial activation step, and allows ortho-C-H borylation with high selectivity. The catalyst displays unprecedented ortho selectivities for a wide variety of substrates that differ in electronic and steric properties, and the catalyst tolerates various functional groups. The regioselective C-H borylation catalyst is readily accessible and converts substrates on gram scale with high selectivity and conversion.

SUBMITTER: Bai ST

PROVIDER: S-EPMC6772079 | biostudies-other | 2019 Sep

REPOSITORIES: biostudies-other

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Hydrogen Bond Directed ortho-Selective C-H Borylation of Secondary Aromatic Amides.

Bai Shao-Tao ST Bheeter Charles B CB Reek Joost N H JNH

Angewandte Chemie (International ed. in English) 20190717 37

Reported is an iridium catalyst for ortho-selective C-H borylation of challenging secondary aromatic amide substrates, and the regioselectivity is controlled by hydrogen-bond interactions. The BAIPy-Ir catalyst forms three hydrogen bonds with the substrate during the crucial activation step, and allows ortho-C-H borylation with high selectivity. The catalyst displays unprecedented ortho selectivities for a wide variety of substrates that differ in electronic and steric properties, and the cataly ...[more]

PMID: 31237988

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