Dichlorotetrakis(pyridine)iron(II)

Dichlorotetrakis(pyridine)iron(II) is the coordination complex with the formula FeCl2(pyridine)4. A yellow solid, it is a prominent example of a transition metal pyridine complex. It is used as an anhydrous precursor to other iron complexes and catalysts. According to X-ray crystallography, the chloride ligands are mutually trans. The complex has a high spin configuration. A monohydrate as well as several related complexes are known, e.g. CoCl2(pyridine)4 and NiCl2(pyridine)4. It is prepared by treating ferrous chloride with an excess of pyridine.