The reaction of FeBr2 and 1 equiv of thallium tris(4,4-dimethyl-2-oxazolinyl)phenylborate (TlToM) in THF provides ToMFeBr (1), whereas FeBr2 and 2 equiv of TlToM react to give (ToM)2Fe (2). Two νCN bands at 1604 and 1548 cm-1 indicated bidentate coordination of ToM to iron in 2. Homoleptic 2 and FeBr2 react in THF overnight through an unusual ligand exchange process to give compound 1, which is apparently the thermodynamic product. The salt metathesis reaction of 1 and KCH2Ph affords ToMFeCH2Ph (3). The effective magnetic moments of compounds 1-3 range from 4.9 to 5.4 μB, and these values are consistent with high-spin iron(II) ( S = 2). A single 1H NMR signal assigned to the methyl groups of the ToM ligand suggested tridentate coordination of the ToM ligand to iron in 1 and 3. X-ray crystallography studies of 1-3 establish their structure as four-coordinated tetrahedral iron complexes. ToMFeBn and CO (1 atm) react to afford isolable ToMFe{C(═O)Bn}(CO)2 (4) as a yellow solid. Complex 4 is diamagnetic ( S = 0), and the three distinct methyl signals in the 1H NMR spectrum are consistent with a six-coordinate, C s-symmetric species. This assignment is supported by its IR spectrum, which revealed intense bands at 2004 and 1935 cm-1 (symmetric and asymmetric νCO), at 1680 and 1662 cm-1 (acyl rotamers, νCO), and at 1593 and 1553 cm-1 (νCN) and is confirmed by a single-crystal X-ray diffraction study.