Triphos as a bidentate ligand: the reactivity of the dangling phosphorus in [PtMe2(triphos-P,P′)]

Complex [PtMe2(triphos-P,P′)], (1) where the linear triphosphine triphos [=bis(diphenylphosphinoethyl)phenylphosphine] acts as a bidentate ligand, can be easily converted in a variety of new complexes due to the reactivity of the free phosphorus donor. The selective oxidation of the uncoordinated phosphorus gave [PtMe2(triphosPO-P,P′)] whose X-ray crystal structure is here reported; from the reactions of 1 with platinum and non platinum precursors homotrimetallic [Pt3Me4XY(triphos)2] (X=Y=Me, Cl, I, X=Me, Y=Cl) and heterotrimetallic ([Pt2PdMe4Cl2(triphos)2] and [Pt2RhMe4(cod)(triphos)2]PF6) complexes were obtained where triphos acts as a chelating/bridging ligand. When 1 was treated with triflic acid in the presence of a neutral electron donor L (L=SMe2, pyridine, PPh3), complexes [PtL(triphos)]2+ were rapidly recovered in high yields. The protonolysis of 1 in the presence of CO and methanol gave the new organometallic complex [Pt(COOMe)(triphos)]OTf.