Cyclic voltammograms for the reduction of l,&dibromo-, l,6-diiodo-, l-bromo-6-chloro-, and l-chloro6-iodohexane at glassy carbon electrodes in dimethylformamide containing tetramethylammonium perchlorate exhibit single irreversible waves that correspond to the reductive cleavage of carbonbromine or carbon-iodine bonds. When large-scale controlled-potential electrolyses of either 1,6dibromoor l,6-diiodohexane are performed at reticulated vitreous carbon, the principal products are n-hexane (30-45%), 1-hexene (28-34%), 1,5-hexadiene (6-16%), and cyclohexane (<7%), with n-dodecane being another significant species obtained from 1,6-diiodohexane. Because a carbonchlorine bond is not directly reducible, 1-bromo-6-chloroand 1-chloro-5-iodohexane give rise mainly to 1-chlorohexane (47-64%), 6-chloro-1-hexene (20-33%), and 1,12-dichlorododecane (2-25%). From these product distributions, and with the aid of experiments done in the presence of deuteriumlabeled reagents, we conclude that the electrolytic reduction of 1,6-diiodoand 1-chloro-6-iodohexane involves both radical and carbanion intermediates, whereas only carbanionic pathways are important for electrolyses of 1,6-dibromoand 1-bromo-6-chlorohexane.