RHODIUM(I) COMPLEXES CONTAINING MONO- AND DITERTIARY PHOSPHINES AND ARSINES

Rhodium dicarbonyl chloride dimer, [Rh(CO)2Cl]2, reacts with cis- and trans-β-styryldiphenylarsine, cri-β-styryldiphenylphosphine, bis(1-propynyl)phenylphosphine, and tris(ferrocenyl)phosphine to give complexes of the type [Rh(CO)ClL2] (L = phosphine or arsine). Using an excess of cis-1,2-bis(diphenylphosphino)ethylene or bis(diphenylphosphinomethyl) ether, ionic complexes of the type [Rh(L-L)2]X (L-L = diphosphine, X = anion) are obtained. Polymeric complexes of formula [Rh(CO)Cl(L-L)]n (L-L = diphosphine) result from the reaction with trans-1,2-bis(diphenylphosphino)ethylene and bis(diphenylphosphino)acetylene. By contrast, complexes of the same empirical formula prepared from bis(diphenylphosphino) methane and its arsenic analog are dimers. When used in a 2:1 molar ratio, cis-1,2-bis (diphenylphosphino)- ethylene and [Rh(CO)2Cl]2 give [Rh(L-L)2] [Rh(CO)2Cl2] (L-L = diphosphine). An analogous reaction with the arsenic analog gives [Rh(CO)(L-L)2] [Rh(CO)2Cl2] (L-L = diarsine). A number of bromo analogs were also prepared. Conductance and infrared spectral data are presented and the structures of the complexes are discussed. © 1969, American Chemical Society. All rights reserved.