Chemistry of the metal carbonyls. Part XLVI. Perfluorobutadienyl iron, rhenium, and manganese complexes

Abstract

Treatment of hexafluorobuta-1,3-diene with the anions [π-C₅H₅Fe(CO)₂]^– and [Re(CO)₅]^– affords the perfluorobutadienyl complexes cis-CF₂:CF·CF:Fe·CF(CO)₂(π-C₅H₅) and trans-CF₂:CF·CF:CF·Re(CO)₅, respectively. The corresponding pentacarbonylmanganese complex cannot be obtained by this route; however, u.v. irradiation of hexafluorobuta-1,3-diene and Me₃Sn·Mn(CO)₅ gives trimethyltin fluoride and cis-CF₂:CF·CF:CF·Mn(CO)₅. In contrast, irradiation of hexafluoro-1,3-butadiene and Me₃Ge·Mn(CO)₅ gives trans-CF₂:CF·CF:CF·Mn(CO)₅, and the complex Me₃Ge·Fe₂·CF₂·CF:CF·Mn(CO)₅ corresponding to an initial 1,4-addition reaction. The i.r., ¹⁹F and ¹H n.m.r. spectra of the compounds are described.