Amide Effects in C-H Activation: Noncovalent Interactions with L-Shaped Ligand for meta Borylation of Aromatic Amides

A new concept for the meta-selective borylation of aromatic amides is described. It has been demonstrated that while esters gave para borylations, amides lead to meta borylations. For achieving high meta selectivity, an L-shaped bifunctional ligand has been employed and engages in an O center dot center dot center dot K noncovalent interaction with the oxygen atom of the moderately distorted amide carbonyl group. This interaction provides exceptional control for meta C-H activation/borylation.