The photochemistry of (η3-2-R-C3H4)Fe(CO)(NO)(X) (R = H or Cl; X = CO or PPh3) in room temperature solution or frozen gas matrixes

A photochemical study of allyl iron complexes of the type, (η3-2-R-C3H4)Fe(CO)(NO)(X) (R = H or Cl; X = CO or PPh3) is presented. These compounds were studied in solid matrixes at 20 K, and at room temperature, by a combination of laser flash at 355 nm and steady-state photolysis. The predominant photochemical process for these compounds is loss of a CO ligand. In addition, exhaustive irradiation of (η3-2-R-C3H4)Fe(CO)(NO)(PPh3) with λexc > 300 nm provided evidence for a haptotropic shift of the allyl group from η3 to η1 coordination.