Photosubstitution of the halide ligands (X−) in (η5-C5H5)Fe(CO)(PPh3)X

Irradiation of CpFe(CO)(PPh3)X, (Cp=η5-cyclopentadienyl, X=Cl, Br or I), 1a–c, with white or red (λ>600 nm) light with maleimide or succinimide and di-iso-propyl amine (dipa) or ethyldi-iso-propyl amine (edipa) in dichloromethane leads to the efficient formation of CpFe(CO)(PPh3)(η1-N-imidato) complexes 2a–b. Irradiation with white light of CpFe(CO)(PPh3)Br in dichloromethane in the presence of an excess of Br− (as tetrabutylammonium bromide) yields CpFe(CO)(PPh3)Br. These results are discussed in terms of possible photoinduced heterolysis of the iron–halide bond in 1a–c.