With the optimal condition in hand, a range of substrates were investigated sequentially. First, we screened different Michael acceptors using 4-phenyl-2-butanol (1) as the alcohol and found that a variety of substrates were applicable as styrene derivatives (Table ). Substrates with alkyl groups such as tBu and Me groups on the aromatic ring easily provided the desired compounds (3, 4). When styrene was used, the reaction proceeded in 72% isolated yield to give the desired compound 5. Gram scale experiment (5) revealed that this reaction proceeded in 75% isolated yield. The investigation of the range of substrates of Michael acceptors continued. The electrochemical deoxygenative Giese reaction proceeded when styrene derivatives with electron withdrawing groups such as fluorine and chlorine, good yields of the desired products were obtained with styrene derivatives containing fluorine substituents (6, 7). And a slightly decrease in yield was observed for styrene derivatives with chlorine substituents (8-10). However, when the reaction was attempted for styrene derivatives substituted with bromine and iodine, the dehalogenation was observed and the desired product was not obtained. Besides, the reaction proceeded for styrene derivatives with different ester groups as electron-withdrawing groups (11-12). The reaction was also applicable to other styrene derivatives such as 1-vinyl naphthalene, 2-vinyl naphthalene, and 4-vinyl biphenyl (13-15). When the disubstituted olefins 1,1-diphenylethylene and α-methylstyrene were applied in the reaction (16-17), the desired product were obtained. As we all know, the functional group transformation of heterocyclic compounds is critical in medicinal chemistry. Therefore, we attempted this reaction for heterocyclic compounds. As a result, the electrochemical deoxygenative Giese reaction proceeded for pyridine, thiazole, thiophene, and Table . Substrate scope of Fe-catalyzed electrochemical deoxygenative Giese reaction a a Isolated yield. b FeCl2 (15 mol%), IPr•HCl (15 mol%), PPh3 (4 eq.), TBAB (4 eq.), and DIPEA (4 eq.) was used. c TBAI (4 eq.) was used instead of TBAB. d FeCl2 (20 mol%), IPr•HCl (20 mol%)), PPh3 (6 eq.), TBAB (4 eq.), and DIPEA (2 eq.) was used.