Synthesis Of Ferrocene Derivatives And Catalysis Of The Complex With Palladium Compounds For The Suzuki-Miyaura Cross-coupling Reactions

Suzuki-Miyaura cross-coupling reaction is the coupling reaction of aryl bromides with phenylboronic acid. It is one of the important methods to couple two organic molecules and thus to form the new C-C bond. In this thesis, several kinds of new ferrocene derivatives were synthesized and the complexes formed with palladium compounds were studied extensively as catalyst for Suzuki-Miyaura cross-coupling reaction. High active and selective catalytic reaction results were obtained:1. Un-functionalized imidazolium salts derived from ferrocene were synthesized via a convenient route. The three ligands were evaluated in Suzuki-Miyaura cross-coupling reaction as catalyst after coordinated to palladium. The yield larger than 91% in the cross-coupling reaction of aryl bromides with phenylboronic acid could be obtained.2. Four sulfoether-functionalized imidazolium salts deriving from ferrocene were synthesized. It was found that the palladium complexes coordinated by the sulfoether-functionalized imidazolium salts were not better in catalytic performance than those coordinated by Un-functionalized imidazolium salts for the cross-coupling reactions.3. The coupling reaction of aryl bromides with phenylboronic acid were also studied as probe reactions of Suzuki-Miyaura cross-coupling reaction using ferrocene derivatives of monophosphine or bidentate ligand coordinated palladium complex as catalyst. It indicates that PPFOMe(1-(diphenylphosphino)-2-(1-methoxyethyl)-ferrocene) was most active for the Suzuki-Miyaura cross-coupling reactions when coordinated to palladium in the ferrocene derivatives. Using the catalyst made from PPFOMe and Pd(OAc)₂(with the mole ratio of 2:1) promoted by K₂CO₃, the yield of 4-methyldiphenyl was reached to 94% at 110℃ when the reaction of 4-bromotoluene with phenylboronic acid was performed for 1h. At the same reaction conditions, all of the aryl bromides tested either electron-poor or electron-rich could reach the yield larger than 90%, indicating that the catalyst of ferrocene derivatives of monophosphine coordinated palladium complex is a better catalyst for the Suzuki-Miyaura cross-coupling reaction.