Synthesis of the first example of a 1,3,4,6-Tetraphospha-hexatriene complex

A convenient access to the first example of a 1,3,4,6-tetraphospha-hexatriene complex, a diphosphene bearing two cyclic dico-ordinated phosphorus substitutents and σ,η2-bonded to Fe(CO)4 units, and characterized by X-ray structure analysis, is described.