Tris(bipyridine)iron(II) chloride is the chloride salt of the coordination complex tris(bipyridine)iron(II), [Fe(C10H8N2)3]2+.
In contrast to tris(bipyridine)ruthenium(II), this iron complex is not a useful photosensitizer because its excited states relax too rapidly, a consequence of the primogenic effect.
[1] The sulfate salt [Fe(bipy)3]SO4 is produced by combining ferrous sulfate with excess bipy in aqueous solution.
This result illustrates the preference of Fe(II) for bipyridine vs water.
Addition of cyanide to this solution precipitates solid Fe(bipy)2(CN)2.