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Palladium P,C,P pincer complexes based on ferrocene were synthesized for the first time. The reaction of 1,3-bis(dialkylphosphinomethyl)ferrocenes {1,3-(R2PCH2)2C5H3}Fe(C5H5) (2a, R=Pr i ; 2b, R=Bu t ) with PdCl2(NCPh)2 in refluxing 2methoxyethanol leads to the corresponding pincer complexes PdCl[{2,5-(R2PCH2)2C5H2}Fe(C5H5)] (3a, 3b). Ferrocene-based binuclear compound 3b reacts with [Cp2Fe]PF6 to form the ferrocenium-based pincer complex {PdCl[{2,5-(Bu t 2PCH2)2C5H2}Fe(C5H5)]}PF6 (4b), and this is the first example of ferrocene-based phosphine chelate oxidation centered on the iron atom. Treatment of complexes 3a and 3b with NaBH4 in refluxing ethanol leads to the complexes Pd(BH4)[{2.5-(R2PCH2)2C5H2}Fe(C5H5)] (5a, R=Pr i ; 5b, R=Bu t ), containing a BH4  group coordinated to the metal in the rarely occurring unidentate mode. The structures of 3a, 3b, and 5b were confirmed by X-ray analyses. Cyclic voltammetric investigations of complexes 2a, 2b, 3a, and 3b are also reported. The structural and spectroscopic features of the palladium ferrocene-based pincer complexes are discussed and compared with those of related compounds.

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