ELECTROCHEMICAL REDUCTION OF ALPHA-UNSATURATED CARBONYL-COMPOUNDS .6. EFFECT OF ELECTROGENERATED BASES IN VERY WEAKLY PROTIC SOLVENTS

Unsaturated carbonyl compounds were reduced electrochemically in carefully dried aprotic solvents. In the absence of protonating impurities, the i-V curves could be modified due to the de-activation of a part of the substrate by the action of the electrogenerated bases. In DMF solutions, the electrogenerated base which is able to deprotonate the ketone is mainly the dianion and discrepancies occur with, classical polarograms, of this class of reactants as observed at the level of the second step. For more conjugated ketones, a very cathodic step is assumed to correspond to the reduction of the conjugated anion of the ketone but the instability of this anion (inducing polymerisation reactions) prevents the acquisition of careful analytical evidence. © 1979 Elsevier Sequoia S.A., Lausanne.