Metal phosphine bridging

Phosphinate groups are solid bridging ligands and metal phosphinates are usually resistant to oxidation and hydrolysis... 

Trivalent metal phosphinates have also been prepared. The chain structure was assumed to consist of triple-bridging phosphinate according to Fig. 11. 

Metal-Metal Bond Making and Breaking in Binuclear Complexes with Phosphine Bridging Ligands... 

Metal-Metal Bond Formation and Rupture in Pi phosphine Bridged Pi nuclear Metal Complexes... 

Metal-halogeno bridge cleavage reactions by PF3 or other phosphines have also been useful in certain cases (method E), e.g.,... 

Figure 1 Chelating phosphine-bridged Pt(I)-Pt(I) metal-metal bonded dimer. (Reprinted with permission from Ref. 1. 2002 American Chemical Society)...

Concerted two-electron transfer and reversible metal-metal bond cleavage in phosphine-bridged dimers have been investigated, and extended Hiickel molecular orbital calculations have shown that the redox-active orbital is a metal-metal antibonding orbital. A Ru-Ru-bonded dimeric cation [Ru(Cp)2]2++ has been prepared and characterized electrochemically. The electrochemistry of these dimers may give insight into more complex clusters and polymeric metals. 

The phosphine-bridged Pd(I) and Pt(I) dimers, M2(dppm)2X2 (dppm = Ph2PCH2PPh2), contain unusually reactive metal-metal bonds that are susceptible to insertion by a variety of species Y to form A-frame bridged structures. 

Properties of poly(metal phosphinates) are dependent on the coordination metal and any accompanying ligand (such as H2O), the nature of the substituents on phosphorus and the number of bridging sites percenter. Poly(metal phosphinates) have been synthesized by reacting solutions of the metal ions with dialkyl- and diarylphos-phinates. 

There already exist examples of significant chemical reactions which demonstrate the unusual reaction characteristic resulting from the presence of two metal centers.Here we examine two, neither of which involves phosphine bridging ligands. The autoxidation of triphenylphosphine catalyzed by four-coordinate iron(II) porphyrins in a noncoordinating solvent like toluene occurs by the mechanism shown in Figure Two... 

---