Session: Undergraduate Research at the Frontiers of Inorganic Chemistry:

Beta diketiminate (BDI) ligands are one of the most common classes of ligands. While bidentate versions have dominated the field, tetradentate BDI ligands are rare and unexplored. To this end, a family of N₂P₂ tetradentate ligands has been designed to stabilize first-row transition metals in different oxidation states by providing both hard and soft donors. First-row transition metals allow for a cheaper, more abundant, and more sustainable alternative to second- and third-row transition metals. The ligands are composed of a BDI backbone appended to pendant phosphine arms by phenyl linkers. In effort to understand the influence of sterics on the ligand binding, methyls groups were introduced at positions 4 and 6 on the phenyl linkers. As an initial study, the structure and binding properties of the ligand were analyzed via subsequent metalation with zinc(II) iodide due to its diamagnetic nature. Two different binding modes were observed in solid state depending on the identity of the substituent at position 6. When hydrogen was present at position 6, the zinc metal binds in a κ⁴ fashion to the ligand, but the presence of a methyl group at position 6 reveals a different binding mode of κ³. The synthesis and characterization of the ligands and zinc(II) complexes will be discussed.

Melanie Nevins

Appearances