Reactions of Trivalent Phosphorus Compounds with Palladium Bis(acetylacetonate). Complexes Catalytically Active in Hydrogenation

Mechanisms of reactions between palladium bis(acetylacetonate) and tertiary and secondary phosphines and alkali-metal diphenylphosphides are discussed. Depending on the conditions, either complex formation or redox processes occur. The mechanism of formation and the nature of microheterogeneous catalysts for hydrogenation are considered using palladium acetylacetonate complexes with tertiary phosphines as an example. Data of NMR and IR spectroscopies, electron microscopy, and X-ray powder diffraction analysis showed that the catalysts are a palladium organophosphorus matrix with nanosize and with immobilized palladium clusters in the zero oxidation state.