Electrocatalytic hydrogenation of alkenes on LaNi5 electrodes

In this paper a new electrocatalytic hydrogenation process is reported base d on the use of LaNi5 electrodes. The charge/discharge of hydrogen within t he intermetallic compound through cyclic voltammetry experiments was observ ed using a powder microelectrode in classical aqueous KOH medium, as well a s in other buffered aqueous or hydro-organic media. Most voltammograms are modified in the presence of unsaturated compounds, which indicates that a h ydrogenation reaction occurs. Electrocatalytic hydrogenation on a preparati ve scale was carried out with three unsaturated compounds taken as models ( methyl vinyl ketone, 1-decene, 5-hexen-2-one) and it was found that only th e C=C bond is hydrogenated with Faradaic efficiencies up to 100%. (C) 2000 Elsevier Science S.A. All rights reserved.