First, an Fe-catalyzed redox-neutral Giese-type reaction was investigated using 4-phenyl-2-butanol (1) and 4-tert-butylstyrene (2) as the substrate (Figure ). The most challenging aspect of this reaction is that the halogenation of the alcohol at the anode electrode and the reduction of the Fe catalyst at the cathode electrode must proceed at appropriate reaction rates and potentials. More than several hundred conditions for the optimization of this redox-neutral Giese-type reaction with respect to metal catalysts, ligands, base, phosphine, Br source, electrolyte, electrode, and current values have been studied extensively. For the screening of the alcohol halogenation reaction at anode electrodes, the conditions of the Ni-catalyzed paired electrolysis approach pioneered by Li et al. were used as initial attempt to investigate the optimal condition for the present reaction. 8 Detailed investigations revealed that the best results were obtained using FeCl2 (15 mol%), IPr ligand (L1) (15 mol%), PPh3 (4 eq.), TBAB (4 eq.), DIPEA (4 eq.), nBu4NBF4 (0.5 eq.) in DMA. In terms of electrochemical conditions, a current of 6 mA (0.2 mmol scale, constant current) was effective at room temperature in an undivided cell, and the redox-neutral Giese reaction of secondary alcohol 1 and styrene derivative 2 was found to proceed with 60% isolation yield using carbon plates as anode electrodes and Ni forms as cathode electrodes.