Stoichiometric applications of acyclic pi-organoiron complexes to organic synthesis

The application of acyclic (diene)iron complexes and (pentadienyl)iron cati ons in organic synthesis has steadily increased over the past 20 years. Thi s is due to their ease of preparation, their stability toward a wide variet y of reaction conditions, the manifold method for removal of the Fe(CO)(3) group, and the low cost of iron carbonyls. The (tricarbonyl)iron adjunct ma y serve in three capacities: i) as a protecting group for conjugated dienes , ii) to direct the formation of chiral centers adjacent to the complexed d ient, and iii) to stabilize the formation of positive charge adjacent or th e complexed diene (i.e. pentadienyl cations). Specific examples of these at tributes will be presented in this review. One of the advantages of stoichi ometric organometallic reagents is the ability to repeatedly utilize the sa me metal center to control a number of different bond forming reactions. Si x examples will be presented which demonstrate this potential for acyclic ( diene)iron complexes and (pentadienyl) iron cations.