Role of Hemilabile Diamine Ligands in the Amine-Directed C–H Borylation of Arenes

A study of the role played by the bidentate ligand used in amine-directed C–H borylation is described. Both reaction conversion and selectivity were significantly impacted when steric congestion and electronic perturbations of the bidentate diamine ligand were made, but a more significant influence was imparted by reducing the bite angle of the ligand. N-Benzylaminopyridine was identified as a general ligand that improves both selectivity and yield for most problematic substrates previously reported with picolylamine as ligand.