Steric Effects in Isopropyl‐Substituted (β‐Diketiminato)Iron Complexes

The preparation and characterization of a series of iron complexes supported by an isopropyl‐substituted β‐diketiminate ligand that is synthesized in a single step are reported herein. The steric environment around the metal center in these complexes blends aspects of reported methyl‐ and tert ‐butyl‐substituted analogs. Both four‐coordinate and three‐coordinate isopropyl (β‐diketiminato)iron(II) chloride complexes were observed by X‐ray crystallography, aligning with the methyl and tert ‐butyl systems, respectively. Importantly, the isopropyl ligand allows access to a stable N ‐mesityl iron imide, a compound that was previously only isolable when supported by the tert ‐butyl‐substituted ligand, which requires four synthetic steps and multiple weeks to prepare. These observations confirm that the intermediate steric burden of this ligand system fosters a balance between synthetic ease and greater stability in (β‐diketiminato)iron complexes.