Comparative reactivity studies of dppf-containing CpRuII and (C6Me6)RuII complexes towards different donor ligands (dppf = l,l'-bis(diphenylphosphino)ferrocene)

[CpRu(dppF)Cl] (Cp = eta(5)-C5H5) (1) and [(HMB)Ru(dppf)Cl]PF6 ((HMB) = eta(6)-C6Me6) (3) react with different donor ligands to give rise to N-, P- and S-bonded complexes. The stoichiometric reactions of 1 and 3 with NaNCS give the mononuclear complexes [CpRu(dppf)(NCS)] (2) and [(HMB)Ru(dppf)(NCS)]PF6 (4). respectively, in yields above 80%, while 3 also gives a dppf-bridged diruthenium complex [(HMB)Ru(NCS)(2)](2)(mu-dppf) (5) in 67% yield from reaction with four molar equivalents of NaNCS. Compound 5 is also obtained in 70% yield from the reaction of 4 with excess NaNCS. With CH3CN in the presence of salts, both I and 3 give their analogous solvento derivatives [CpRu(dppf)(CH3CN)]BPh4 (6) and [(HMB)Ru(dppf)(CH3CN)] (PF6)(2) (7). With phosphines, the reaction of 1 gives chloro-displaced complexes [(CpRu(dppf)L]PF6 (L = PMe3 (8), PMe2Ph(9)), whereas the reaction of 3 with PMe2Ph leads to substitution of dppf, giving [(HMB)Ru(PMe2Ph)(2)Cl] PF6) (10). The reaction of 1 with NaS2CNEt2 gives a dinuclear dppf-bridged complex [{CpRu(dppf)}(2)([mu-S-2)](BPh4)Cl (13), whereas that of 3 results in loss of the HMB ligand giving a mononuclear complex [Ru(dppf)(S2CNEt2)(2)] (12). With elemental sulfur S-8, 1 is oxidized to give a dinuclear CpRuIII dppf-chelated complex [{CpRu(dppf)}(2)(mu-S-2)](Bph(4))Cl (13), whereas 3 undergoes oxidation at the ligand, giving a dppf-displaced complex [(HMB)Ru(CH3CN)(2)Cl]PF6 (14) and free dppfS(2). The structures of 1, 2, 5-9. 11, 13 and 14 were established by X-ray single crystal diffraction analyses. Of these, 5 and 11 both contain a dppf-bridge between Ru-II centers, while 13 is a dinuclear CpRuIII disulfide-bridged complex; all the others are mononuclear. All complexes obtained were also spectroscopically characterized. (C) 2004 Elsevier B.V. All rights reserved.