When butadiene was added to a suspension of Fe2(CO)9 in n -hexane, a reaction occurred w...

When butadiene was added to a suspension of Fe₂(CO)₉ in n -hexane, a reaction occurred which, on isolation of product, yielded orange liquid Q . Compound Q had the following characteristics: IR: bands at 2071, 2005, and 1975 cm ⁻¹ ; calculations suggested that another band was hidden under one of these bands.

Finally, reaction of Q with PPh ₃ gave Fe(CO) ₄ (PPh ₃ ) (Ph = phenyl) Identify and sketch Q. (G. J. Reiss, M. Finze, J. Organomet. Chem. , 2011 , 696 , 512.)