Ioana Fechete and Viatcheslav Jouikov
University of Strasbourg, France, and others

Series: Chemistry Research and Applications
BISAC: SCI013000

Direct electrochemical reduction of phthalimide at the cathodes such as Hg, In, Cd and Ag amalgam electrodes in aqueous-organic solutions (H2O-CH3CN acidified with H2SO4 or HCl) was elaborated. This process results in the removal of both carbonyl groups of phthalimide thus providing isoindoline (2,3-dihydro-1H-isoindole) selectively and with high substance yield. In contrast to earlier works, the current efficiency of the present method is close to the substance yield. The crucial conditions for high efficiency of this process were shown to be: i) the use of cathodic materials with high overpotential of the reduction of protons, ii) maintaining the potential of the working electrode in the range of -1.2…-0.9 V vs SCE, and iii) continuous correction of the acidity of catholyte keeping it at the optimal level (pH = 2.5) throughout the duration of the electrolysis. The importance of using carbon-based anode materials is also underlined. (Imprint: Nova)