A range of 1,7-diarylheptane-1,7-diones were electrooxidized in the presence of iodide
ions and a base in a mixture of methanol and toluene as the reaction solvents to give
the corresponding cyclized 1,2-diaroylcyclopentanes in moderate to good yields. The
reactions were carried out under extremely mild reaction conditions for which the
optimal amount of electrolytic current varied from 2.05–3.17 F·mol–1 depending on the substrates. The reaction presumably proceeds through a two-electron
oxidation process in which the iodide ion plays an important role as the electron
carrier.
Key words
electron transfer - oxidation - cyclization - ring closure - green chemistry - iodine