Silver complexes phosphorus-donors

The reaction of phosphorus-donor ligands with silver(I) ions has traditionally been centred on tertiary arylphosphines. The synthesis of complexes with tertiary phosphites has often been... 

The use of cyclic voltammetry has already been mentioned in the characterizations of nickel(II) complexes with nitrogen- and phosphorus-donor ligands and of ruthenium(II) terpyridine bipyridine complexes with a phosphorus(III) ligand.Similarly, it has been used in the characterization of bis(diphenylphosphinomethyl)amino ligands and their Ni(II) and Pd(II) complexes. " A novel electrochemical sensor for detection of Dimethoate insecticide, and other similar organophosphates (OPs), based on a thin film-imprinted polymer, has been produced using electrodeposition of silver nanoparticles and electropolymerisation controlled by cyclic voltammetry scans " and more details are given later under sensors and biosensors. 

Although trialkyl- and triarylbismuthines are much weaker donors than the corresponding phosphorus, arsenic, and antimony compounds, they have nevertheless been employed to a considerable extent as ligands in transition metal complexes. The metals coordinated to the bismuth in these complexes include chromium (72—77), cobalt (78,79), iridium (80), iron (77,81,82), manganese (83,84), molybdenum (72,75—77,85—89), nickel (75,79,90,91), niobium (92), rhodium (93,94), silver (95—97), tungsten (72,75—77,87,89), uranium (98), and vanadium (99). The coordination compounds formed from tertiary bismuthines are less stable than those formed from tertiary phosphines, arsines, or stibines. 

Tetracarbonyl cations [Cr(CO)4(L2)]+, where L2 represents arylphosphines, alkyl, or aryl phosphites, or a bidentate ligand with phosphorus or arsenic donor atoms, have been produced by both chemical and electrochemical means. However, oifly one of these complexes, namely, tra i -[Cr(CO)4(PPh3)2]+, is stable enough to be isolated as the perchlorate salt. Exposure to light and moisture produces tra i -Cr(CO)4(PPh3)2 via disproportionation. Just as easily isolated, but somewhat less sensitive, are the [Cr(CO)3(PR3)3]+ cations. " Oxidation with a silver ion or NO+ converts the /uc-(R3 = Me2Ph, (OMe)3) and mer-(R3 = (OMe)3, (OMe)2Ph, (OPh)3) complexes into Cr products with mer structures. Light and heat promote the formation of reduced wer-Cr(CO)3 (PR3)3. These tetra(carbonyl) and tri(carbonyl) cations have been the subject of ESR spectroscopy and theoretical study. 

When the same molecule is titrated with silver ions, complexes appear to exist for a 2 1 mole mole compound and also at the 1 1 and 1 2 points. Six donor molecules are present in the 2 1 complex but only a maximum of four can be involved. The 2 1 complex may again involve chelation effects with both phosphorus and two nitrogen atoms or may be simply coordination of two phosphorus atoms. The low mcp value would tend to favor chelation, since the mcp value for eventributylphosphine is -555 mv while for this compound it is -621 mv. At... 

---