Synthesis, characterization, and reactivity of a ruthenium(II) N,N′,N″-tris(2-pyridyl)phosphine complex. X-ray analysis of RuCl₂(PPh₃)(Ppy₃) (py = 2-pyridyl)

Reaction of RuCl₂(PPh₃)₃ with Ppy₃ (py = 2-pyridyl) in benzene produced the N,N′,N″-Ppy₃ complex RuCl₂(PPh₃)(Ppy₃) 1. Crystals of RuCl₂(PPh₃)(Ppy₃)•2CH₂Cl₂ (C₃₅H₃₁Cl₆N₃P₂Ru) are monoclinic, a = 17.269(2), b = 10.797(1), c = 20.604(1) Å, β = 107.461(6)°, Z = 4, space group P2₁/c. The structure was solved by the Patterson method and was refined by full-matrix least-squares procedures to R = 0.039 and R_w = 0.035 for 4184 reflections with I ≥ 3σ(I). Complex 1 reacts in MeOH or benzene with two-electron donors (L) to give the chloride-substituted, [RuCl(L)(PPh₃)(Ppy₃)]PF₆, or the triphenylphosphine-substituted products, RuCl₂(L)(Ppy₃), (L = CO, MeCN, PhCN), respectively. [RuCl(MeOH)(PPh₃)(Ppy₃)]BPh₄ was also isolated. The non-coordinated phosphorus atom in 1 was oxidized to form RuCl₂(PPh₃)(OPpy₃). Key words: ruthenium, pyridylphosphines, crystal structure