Palladium-Catalyzed Reduction of Multiple Bonds with Mg/CH₃OH

It has long been known that magnesium in methanol (or in ethyl or isopropyl alcohol) can been used for the reduction of carbon-heteroatom double bonds^[1] and N-oxides^[2]; more recently, the selective reduction of α,β-unsaturated nitriles^[3a] and aryl-substituted ethylenes has also been achieved in this way^[3b]. In all these reactions, however, isolated, nonactivated double or triple bonds were found unaffected by the reducing system. We now wish to report that addition of catalytic palladium metal on carbon to the Mg/CH₃OH reagent dramatically enhances its reactivity, thus allowing rapid and facile reduction of nonactivated multiple bonds (Table 1)…