Diphenylphosphinopyridine (PPh2Py) versus 2-(2-diphenylphosphinomethyl)pyridine (PPh2CH2Py) in the coordination to ruthenium centres: Study of the reaction of PPh2Py containing formato-bridged dinuclear Ru(I) complexes and PPh2CH2Py containing mononuclear

Dinuclear carboxylato-bridged Ru(I) complexes [Ru2(μ-RCOO)2(CO)4L2] (L = RCOOH; R = H, Me) were reacted with diphenylphosphinopyridine (PPh2Py) and 2-(2-diphenylphosphinomethyl)pyridine (PPh2CH2Py) ligands.In agreement with previously reported results, the reaction with PPh2Py preserves the dinuclear structure of Ru(I) complexes [Ru2(μ-RCOO)2(CO)4(PPh2Py)2] (R = H (1) and Me (2)).On the other hand, the reaction with PPh2CH2Py leads to the formation of mononuclear ionic Ru(II) complexes of the type [Ru(RCOO)(PPh2CH2Py)(CO)2][RCOO] (R = H (3) and Me (4)).The reaction of 1 with HS(CH2)nSH (n = 2, 3) gives dinuclear dithiolato-bridged Ru(I) complexes [Ru2(μ-S(CH)nS)(CO)4(PPh2Py)2] (n = 2 (5), 3 (6)).The equivalent reaction of HSCH2CH2SH with 3 forms the mononuclear neutral complex[Ru(S(CH2)2S)(CO)2(PPh2CH2Py)] (7). These complexes were characterised by elemental analyses, IR, 1H, 13C and 31P NMR spectroscopies. Additional liquid mass (with electrospray) spectrometry was used for complexes 3 and 4.