A dry glass fibre Soxhlet thimble was charged with anhydrous iron(II) chloride (5.0 g, 39.4 mmol) inside an inert gas glove box and connected to a round-bottomed Schlenk flask filled with anhydrous THF (200 cm³). The apparatus was purged thoroughly with argon and the solvent heated under reflux for 4 d by which time all the metal chloride had been extracted. The compound had already begun to separate as a white microcrystalline solid. The solution was left to cool to ambient temperature and concentrated to ca. 50cm³ before the solid was collected by cannula filtration and dried in vacuo for 3 h. (8.5 g, 92 %).

Anal. Found (Calcd. For C₁₂H₂₄Cl₄Fe₂O₃): C 30.58 (30.68); H 5.16 (5.15) %