Liquid phase hydrogenolysis of dibenzyl ether over metals of the VIIIth group

It has been shown that depending on the catalyst and the solvent used, during the conversion of dibenzyl ether to toluene hydrogenolysis of C-O ether bonds, dehydrogenation and hydrogenolysis of benzyl alcohol formed, hydrogenation and decarbonylation of benzaldehyde, and the recombination of benzyl radicals and the benzylation of toluene can take place. The activity of catalysts in hydrogenolysis reactions of dibenzyl ether and benzyl alcohol to produce toluene decreases as follows: Pd/C>Pd>Raney Ni>Rh, whereas the selectivity drops down in the order: Raney Ni>Pd>Pd/C>Rh. The reaction rates depend on the solvent and diminish in the order: ethanol>2-propanol>benzene.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1257–1261, July, 1993.