Preparation, characterization and electrochemical studies of 1,1′-bis(diphenylphosphino)ferrocene (dppf) derivatives. Crystal structure of [dppfCo(NO)2] [SbF6]

Article abstract of DOI:10.1016/S0020-1693(97)05527-8

The neutral dppfFe(NO)₂ (1), the novel cationic [dppfCo(NO)₂] [SbF₆] (2), as well as the dppfFe(CO)₃ (3) (dppf=1,1′-bis-(diphenylphosphino)ferrocene) complexes were prepared and characterized. The interaction between the two metallic centers through the dppf ligand was studied in the solid state by ⁵⁷Fe Moessbauer spectroscopy and in solution by cyclic voltammetry. The Moessbauer parameters are compared with those of other dppfML_n complexes. Electrochemical studies performed on these complexes show the great influence of the ML_n moiety on the redox processes of the dppf iron center. The crystal structure of complex 2 was determined (C₃₄H₂₈CoF₆FeN₂O₂P ₂Sb). The compound crystallizes in the triclinic, space group P1, a = 10.441(2), b= 10.755(2), c= 17.320(5) A, α = 104.10(2), β = 0.504(10), γ = 111.504(10)°, U= 1744.7(7) A³, Z = 2, R = 0.0765, wR2 = 0.1878. In this complex, the cobalt atom is coordinated to two nitrosyl ligands and to phosphorus atoms of the dppf ligand, providing a distorted tetrahedral geometry.