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Iron β-diketonate compounds are reported using the hindered 2,6-dimesitylbenzoyl pinacolone (^Aracac), which sterically precludes formation of tris-^Aracac complexes. Fe(^Aracac)₂ (1), Fe(^Aracac)₂Cl (2) were synthesized and characterized using crystallographic, spectroscopic, elemental analysis, and electrochemical techniques. Iron complexes with only one ^Aracac ligand form dimers [Fe(^Aracac)(THF)₂]₂(μ-OTf)₂ (3) and [(^Aracac)Fe(μ-mesityl)]₂ (4). Complexes 1–4 were evaluated in a Kumada cross-coupling reaction and compared with the parent Fe^III(acac)₃ complex. Whereas the bis-acac complexes 1 and 2 show only modest activity (∼50 % yield after 60 min), the mono-acac complexes 3 and 4 are nearly as effective as the parent compound (∼90 % yield). DFT computations, in conjunction with catalytic results and electrochemical observations, suggest a catalytic cycle involving an oxidative addition of an …