Hydrogen Bond Directed ortho‐Selective C−H Borylation of Secondary Aromatic Amides

Angewandte Chemie International Edition
Hydrogen Bond Directed ortho‐Selective C−H Borylation of Secondary Aromatic Amides

Shao-Tao Bai, Charles B. Bheeter, Joost N. H. Reek
Angewandte Chemie, International Edition, (2019), 58(37), 13039-13043
DOI: 10.1002/anie.201907366

      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.