Molecular Structures and Catalytic Activity of Palladium Complexes Derived from Lutidine-bridged Bis(benzimidazolin-2-ylidene) Ligands
نویسندگان
چکیده
Reaction of lutidine-bridged dibenzimidazolium dibromides 1 – 4 with palladium acetate gives pincer-type palladium complexes of the type [Pd(L)Br]Br [5]Br–[8]Br. Crystals suitable for an X-ray diffraction study have been obtained by slow evaporation of the solvent from dichloromethane/methanol solutions of [7]Br and [8]Br. The crystal structure of [7]+ reveals a pincer topology of the cationic complex with a distorted square-planar coordination geometry at the metal center. From a solution of complex [8]Br, a dinuclear byproduct [9]+ was obtained with two bis(benzimidazolin2-ylidene) ligands coordinating in a bridging fashion. The pincer-type palladium complexes [5]Br– [8]Br were tested as precatalysts in Suzuki coupling reactions.
منابع مشابه
Palladium(II) Complexes with Benzoxazol-2-ylidene Ligands: Crystal Structures of trans-Chloro(benzoxazol-2-ylidene)- bis(triphenylphosphine)palladium(II) Chloride and cis-Diiodo(benzoxazol-2-ylidene)(triphenylphosphine)palladium(II)
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