Prakash has demonstrated that Mg powder suspended in water, acetic acid, and DMSO is an efficient reductant for benzotrifluoride carrying a nitrile group. Our group has discovered that a low-valent nickel complex is an active catalyst for the hydrodefluorination of 1-trifluoromethyl naphthalene using hydrosilane as a hydride source. We have revealed that the low-valent nickel complex directly cleaves a C(sp 3 )-F Nickel-catalyzed exhaustive hydrodefluorination of perfluoroalkyl arenes 5 bond of the benzotrifluorides via oxidative addition, which was studied by stoichiometric reactions and density-functional-theory (DFT) calculations.