Kinetics of the catalytic reduction of peroxides and hydroperoxides

Abstract

1. The kinetics and sequence of the hydrogenation of the bonds in 3-methyl-1-butyne 3-hydroperoxide and p-nitrobenzoyl peroxide were studied. The reaction order, rate constants and activation energy of the given processes were determined. 2. Making use of the energetics principle of the multiplet theory, it proved possible to predict the hydrogenation sequence of the bonds in bifunctional compounds on a nickel catalyst. The height of the energy barriers for the hydrogenation of various bonds was calculated. 3. In complete harmony with the multiplet theory, in the case of 3-methyl-1-butyne 3-hydroperoxide the peroxide group is the first to hydrogenate in the presence of a nickel catalyst, and then the acetylenic bond. In the case of p-nitrobenzoyl peroxide, it is the nitro group that hydrogenates first, and only after this does the peroxide group hydrogenate. 4. The hydrogenation sequence depends on the nature of the catalyst, which is in harmony with the theory. In the presence of Pd-black, for the case of 3-methyl-l-butyne 3-hydroperoxide, it is the acetylenic bond that hydrogenates first, and only after this does the peroxide group hydrogenate. The last to hydrogenate is the ethylene bond. In the presence of Pt-black, strict selectivity is observed only in the hydrogenation of the triple C≡C and double C=C bonds.