ELECTROCATALYTIC HYDROGENATION OF ORGANIC-COMPOUNDS - PART XI - THE INFLUENCE OF A NON-MICELLE-FORMING SURFACTANT ON THE ELECTROCATALYTIC HYDROGENATION OF CARVONE AND LIMONENE IN AQUEOUS-MEDIUM AT RANEY-NICKELELECTRODES

The electrocatalytic hydrogenation (ECH) of carvone (1) and limonene ( 8) at a Raney nickel cathode was studied in aqueous solutions containi ng a non-micelle-forming surfactant (didodecyldimethylammonium bromide , DDAB). The efficiency of ECH of these substrates was markedly increa sed compared to that observed previously with micelle-forming surfacta nts, and this for very low DDAB concentrations, as a consequence of th e strong adsorption of DDAB on the electrode. For the ECH of 8 in basi c medium (pH 10), the major part of organic compounds (60-95%) was sho wn to be adsorbed on the electrode surface as an organic layer stabili zed by an interfacial film of DDAB.