This thesis describes the use of both, a carbanion Payne-type rearrangement and η4-dienyl and η5-pentadienyl iron tricarbonyl complexes in organic chemistry. A carbanion Payne-type rearrangement has been developed and its reactivity investigated, with the subsequent trapping of a series of aldehydes or imines. The results are disappointing with no desired tetrahydrofuran-, tetrahydropyran- or pyrrolidine-containing molecules synthesised, although reasons for this are discussed. A novel 1,3-dipole containing a η5-iron tricarbonyl pentadienyl complex was synthesised on opening of a cyclopropane, subsequently trapping with a series of aldehyde and imines to efficiently form tetrahydrofuran and pyrrolidine ring structures, respectively.