Synthesis and Characterization of Aluminum Complexes Implementing Redox-Active Nitroxide Bidentate Ligands
Date of Award
© 2022 Omar Saleh. This work is freely available courtesy of the author. It may be used under the terms of the Creative Commons Attribution 4.0 International (CC BY 4.0) license. For all other uses, please contact the copyright holder.
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Bachelor of Arts
Chemistry & Biochemistry
Christopher R. Graves
Aluminum is an abundant, sustainable, and non-toxic metal, which would be a great candidate to be used in redox and catalytic chemistry in lieu of the currently used heavy metals. However, aluminum can only exist over one stable oxidation state, which is a major obstacle in this pursuit. To tackle this issue, the Graves Lab has been focusing on incorporating redox active ligands into aluminum complexes. Nitroxide (NO⁻) is an exceptionally important functional group, as it can reversibly exist over three stable oxidation states. In this work, I synthesized and characterized neutral aluminum complexes, [(^(OMe)pyNO)AlMe₂]₂ (1b) and [(^(OMe)pyNO)AlMe₂]AlMe₃ (2b), with a redox-active pyridyl-based nitroxide ligand (^(OMe)pyNO⁻). These complexes were characterized using XRD crystallography, DFT, and ¹H and ¹³C NMR. We also investigated the redox activity of those complexes using cyclic voltammetry. In addition to that, this project focuses on the reactivity of the dimeric aluminum complexes 1a and 1b with different group 13 metal trihalide Lewis acids (AlCl₃, GaCl₃, InCl₃, GaBr₃, AlI₃). Those reactions resulted in the formation of novel cationic dinuclear aluminum complexes (3a, 3b, 4a, and 5a), which exhibited an intriguing ligand rearrangement. Herein, we report the synthesis and characterization of those novel complexes, as well as an investigation of their redox activity. We also discuss preliminary detail into the mechanism of the reaction that yields those cationic complexes.
Saleh, Omar , '22, "Synthesis and Characterization of Aluminum Complexes Implementing Redox-Active Nitroxide Bidentate Ligands" (2022). Senior Theses, Projects, and Awards. 259.