Date of Award
Dissertation (Access Restricted)
Doctor of Philosophy
Theodore J Burkey
Paul S Simone
It is known that the redox-active ligand N,N’-bis(3,5-dimethylphenylimino)acenaphthene (BIAN) behaves noninnocently with early transition metals Ti, V, and Cr. New homoleptic BIAN complexes of the type M(BIAN)3, where M = Zr, Hf, Mo, and W, have been prepared and spectroscopically examined for the purpose of comparing their electronic behavior with their lighter row 4 analogues. These complexes were also inspected for the purpose of constructing a catalogue of isostructural species, for which prudent design of donor-bridge-acceptor (DBA) complexes using an organic BIAN derivative as the bridging ligand can be achieved. Electronic characterization revealed that BIAN exhibits noninnocent behavior with Zr, Hf, Mo, and W, which act as bridges mediating electron transfer between the ligands. Complexes of the type M(BIAN)2(CO)2, where M = Mo and W, were synthesized and characterized for use as capping complexes in the development of modular wire complexes. By extending BIAN to its bifunctional derivative, the tetrakis(3,5-dimethyphenylimino)pyracene (TIP) ligand is formed. The electronic properties of homoleptic BIAN complexes helped to guide the rational design of TIP-based molecules which exhibit metal-metal coupling. Various homobimetallic species were isolated from ligation of TIP to the metals Ti, Zr, Hf, and Cr. Through spectroscopic characterization, metal-metal coupling was observed in all mixed valent complexes via electron delocalization and/or magnetic coupling. The TIP ligand was found to be noninnocent with early transition metals, and capable of mediating long range (~11 Å) electronic communication. These species act as prototypes for the development of TIP-based DBA wires and other electroactive molecules. The comparison of group 4 and 6 congeners is expected to provide guidance in the future development of heterobimetallic TIP-based wires featuring directional electron transfer.
Dissertation or thesis originally submitted to ProQuest
Bell, Colby Seth, "Facilitating Strong Metal-Metal Coupling in Complexes Bridges by a Noninnocent Tetrakis(imino)pyracene Ligand" (2023). Electronic Theses and Dissertations. 3053.