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Abstract: The “Ru(P–P)” unit (P–P=diphosphine) is recognized to be an important core in catalytic species for hydrogenation of unsaturated organic substrates. Thus, in this study we synthesized six new complexes containing this core, including the binuclear complex [(dppb)(CO)Cl2Ru-pz-RuCl2(CO)(dppb)] (pz=pyrazine) which can be used as a precursor for the synthesis of cationic carbonyl species of general formula [RuCl(CO)(dppb)(N–N)]PF6 (N–N=diimine). Complexes with the formula [RuCl(py)(dppb)(N–N)]PF6 were synthesized by exhaustive electrolysis of these carbonyl compounds or from the precursors [RuCl2(dppb)(N–N)]. The new complexes were characterized by microanalysis, conductivity measurements, IR and 31P{1H} NMR spectroscopy, cyclic voltammetry and X-ray crystallography. [Copyright &y& Elsevier]

Abstract: New tetraruthenated manganese (III) porphyrins were synthesized and characterized (31P NMR, cyclic voltammetry, UV–Vis). This new system presents four units of cationic “[RuCl(dppb)(X-bipy)]+”. The electrochemical and catalytic properties of the central manganese (III) show dependence on the characteristics of the peripheral ruthenium complexes as evidenced by the Mn(III)/Mn(II) reduction potential. The catalytic oxidation reactions of olefins, cyclohexene and cyclohexane, were carried out in the presence of tetrapyridyl manganese (III) porphyrins containing cationic ruthenium complex and using iodosylbenzene as oxygen donor. The performance of these new tetraruthenated porphyrins systems were evaluated and compared with the manganese porphyrin. [Copyright &y& Elsevier]