Fluorocarbon complexes of the transition metals. Part III. Chemistry of tertiary arsine derivatives of tetrakis(trifluoromethyl)rhodacyclo-pentadiene
Abstract
The five-co-ordinate rhodacyclopentadiene complexes [RhClL2C4(CF3)4][L = AsMe3, AsMe2Ph, or AsMe2-(p-MeOC6H4)] react readily with a variety of neutral ligands to give six-co-ordinate species [RhClL′L2C4(CF3)4][L′= py, NH3, MeCN, PHPh2, P(OMe)3, AsMe3, or P(OCH2)3CC2H5]. The corresponding six-co-ordinate carbonyl complexes [Rh(CO)ClL2C4(CF3)4] react with silver salts to produce [Rh(CO)XL2C4(CF3)4](X = CF3CO2–or ClO4–) or [RhXL2C4(CF3)4](X = CH3CO2– or p-MeC6H4SO3–). These same complexes also react with [Tl(dike)] to give [Rh(dike)L2C4(CF3)4][dike = acetylacetonate(acac) or hexafluoroacetylacetonate(hfac)]. Treatment of [RhCl(CO)L2C4(CF3)4] with AgClO4 followed by a neutral ligand gives the complexes [RhL2′L2C4-(CF3)4][ClO4][L′= MeCN or P(OMe)3; L2′= diars]. In the complexes [RhClL′L2C4(CF3)4](L′= py, MeCN, AsMe3, or H2O), L′ undergoes exchange in solution at 30 °C. Static six-co-ordinate structures for these complexes can be achieved at low temperatures. The 1H and 19F spectra of these complexes over a range of temperatures were measured and the results are discussed, I.r. and 1H and 19F n.m.r. spectra of the remaining complexes are also discussed.