Re(V)–oxo–dppf and Re(V)–imido–dppf complexes: synthesis, structure, and properties of Re(X)Cl3(dppf) (X=O, NPh, N-C6H3-2,6-i-Pr2; dppf=Fe(η5-C5H4PPh2)2)

Re(V)–imido and Re(V)–oxo complexes containing 1,1′-bis(diphenylphosphino)ferrocene (Fe(η5-C5H4PPh2)2, dppf) were prepared from mer,trans-Re(O)Cl3(PPh3)2 (1), mer,trans-Re(NPh)Cl3(PPh3)2 (2), or mer,cis-Re(N-C6H3-2,6-i-Pr2)2Cl3(py) (3). Compounds 1–3 reacted with dppf to give fac-Re(O)Cl3(dppf) (4), fac-Re(NPh)Cl3(dppf) (5), and mer-Re(N-C6H3-2,6-i-Pr2)Cl3(dppf) (6), respectively. Electrochemical studies performed on Re–oxo–dppf complexes (4) and Re–imido–dppf complexes (5 and 6) showed different redox behavior depending on the type of ligand coordinated to the Re metal. The structure of compound 4 was determined by X-ray diffraction.