A stereospecific intramolecular iron tricarbonyl-promoted aldehyde-diene cyclocoupling reaction was investigated by using simple substrates 6 and more complicated substrates 30a/30b. Demetalation of the initial products converts all complexed dienes to their pure organic counterparts. In addition, the nickel-catalyzed carbonyl-ene reaction and the Prins reaction were investigated with two different substrates.