A DFT Study on the Mechanism of Nitrogen-directed Intramolecular Aromatic Borylation: C–H Bond Activation or Friedel–Crafts Reaction?

Density functional theory (DFT) calculations of nitrogen-directed intramolecular electrophilic borylation reaction of arenes, which is widely used for construction of functional molecules, indicate that the reaction proceeds through an intramolecular Friedel–Crafts route, rather than through C–H insertion, and the reactivity difference between BCl3 and BBr3 is due to the higher electronegativity of Cl.