Ruthenium complexes with phosphines containing the 1-pyrenyl substituent

Abstract

The synthesis of eight Ru complexes with the general formula [RuI2(h6-arene)(PPyrR2)] (Pyr = 1-pyrenyl; arene = methyl benzoate or p-cymene), is described. These species were obtained from the parent dichlorocomplexes by treatment with an excess of sodium iodide in refluxing technical acetone for a period between 4 h and 11 days depending on the complex. Ru1-Ru4 stands for p-cymene complexes while Ru1’-Ru4’ are methyl benzoate complexes. Their structures were confirmed by IR, multinuclear NMR (31P, 1H, 13C), MS, EA and in three cases by single crystal X-ray diffraction. The antitumoral activity of these iodinated ruthenium complexes was studied against several cell lines and the results are promising compared to the chlorocomplexes. The synthesis of five new (1-pyrenyl)phosphines is also described. These ligands were designed taking into account the relation between the antitumoral activity and the bulkiness of the phosphines in dichlorocomplexes. The ligands have been obtained from the known dichlorophosphine L0. These phosphines were prepared adapting literature methods and have been characterised by the usual techniques.