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.