Photochemical substitution of two carbonyl ligands of tricarbonyl(η5‐cyclopentadienyl)manganese by the butadienes, hexafluorobuta‐1,3‐diene (1a), 1,1,2,4,4‐pentafluorobuta‐1,3‐diene (1b), 1,1,4,4‐tetrafluorobuta‐1,3‐diene (1c), 1,1,2‐trifluorobuta‐1,3‐ diene (1d) und 1,1‐difluorobuta‐1,3‐diene (1e) yields the correspond‐ ing half sandwich complexes carbonyl (η4‐butadiene) (η5‐cyclopentadienyl)manganese (2a‐e), respectively. According to the IR spectrum of 2a‐e, the π acceptor strength increases with the number of fluorine atoms within the ligands 1a‐e. 2a reacts with oxygen at ambient temperature forming μ‐oxo‐bis[(cyclopentadienyl)(η1‐η1‐1,1,2,3,4,4‐hexafluorobut‐2‐en‐1,4‐diyl)manganese(IV)] (3). The structures of 2a, 2c and 3 were elucidated by X‐ray crystallography demonstrating the difference in coordination of the butadiene ligands.