抄録
The electrolytic reduction of 1, 5-cyclooctadiene was carried out in hexamethylphosphoric triamide (HMPA) -ethanol or 1-propanol in the presence of lithium chloride.
The relative amounts of cyclooctene and cyclooctane obtained by the electrolytic reduction of cyclooctadiene at constant currents depend on the kind of alcohols and the concentration of HMPA.
The investigation on the time change of the electrolytic reduction shows that the conversion increased with time, but the current efficiency increased firstly with time and decreased gradually after passing a maximum, followed by increases in the cathode potential.
The experiment with various current densities under the constant total amount of electricity shows that, when the current density was relatively low, it scarcely affected the conversion, the selectivity, and the current efficiency.
The use of 1-propanol afforded high amount of cyclooctene than that of ethanol, probably owing to its lower acidity.
The selective reduction of 1, 5-cyclooctadiene into cyclooctene was performed nearly perfect by adopting the conditions of lower concentration of the proton donor with relatively low acidity, and of the higher current density.
