Studies of ruthenium(II) porphyrins containing tertiary diphosphine ligands, including the crystal structure of (5,10,15,20-tetraphenylporphinato)bis(bis(diphenylphosphino)methane) ruthenium(II)-dichloromethane

Article abstract of DOI:10.1021/ic50219a044

The ruthenium(II) porphyrins Ru(porp)(PP)₂, containing tertiary diphosphine ligands, have been prepared in high yields from Ru(porp)(CO)(C₂H₅OH) [porp = dianion of octaethylporphyrin (OEP) or tetraphenylporphyrin (TPP)] and the PP phosphines [Ph₂P(CH₂)_nPPh₂ (n = 1, 2) and Ph₂P(CH₂)₂N(C₂H₅)(CH ₂)₂PPh₂]. The crystal structure of Ru(TPP)(Ph₂PCH₂PPh₂)₂ shows six-coordinate ruthenium situated in the porphyrin plane and coordinated to two axial monodentate phosphine ligands, which each have a free dangling phosphorus atom. The analogous bis(1,2-bis(diphenylphosphino)ethane) complex almost certainly has the same structure and is the first reported case of a compound containing this common diphosphine in a monodentate fashion. The ³¹P NMR spectra of the Ru(porp)[Ph₂P(CH₂)_nPPh₂]₂ compounds indicate further structures in solution, including species with a chelated diphosphine. An isolated Ru(OEP)[Ph₂P(CH₂)₄PPh₂] complex is likely a polymer incorporating diphosphine bridges.