Electronic Theses and Dissertations

Date

2020

Document Type

Dissertation

Degree Name

Doctor of Philosophy

Department

Chemistry

Committee Chair

TImothy Brewster

Committee Member

Theodore Burkey

Committee Member

Xuan Zhao

Committee Member

Tomoko Fujiwara

Abstract

Heterobimetallic systems have seen an increase in development over the last several years. These bimetallic systems typically involve two transition metals with unique properties used in tandem to activate chemical bonds. Many of these systems use transition metals, consisting of a soft, electron rich (low valent) metal and a harder, electron deficient (high valent) metal. These types of heterobimetallics can be exploited as an intramolecular Lewis acidLewis Base pair, which allows access to reactivity that may not be accessible to one transition metal alone.Relatively unexplored is the use of a late transition metal (LTM) in tandem with a Lewis-acidic p-block (Group 13) metal. LTM-Lewis acid bimetallic complexes can be broadly categorized into two separate families, both capable of cooperative activation of a chemical bond. Among Group 13 Lewis acids specifically, aluminum is of particular interest to the Brewster laboratory due to it being earth-abundant and the most electropositive Group 13 element. Bimetallic complexes that contain an aluminum moiety are relatively unexplored compared to their boron analogs due to being highly reactive species and their synthetic difficulty. This has made their isolation and characterization quite challenging. The goal of the Brewster lab is to develop bimetallic systems that contain aluminum and an electron-rich transition metal and to exploit cooperative reactivity between both metal centers. In this dissertation, we describe the successfully completed syntheses of bi- or tridentate ligands for our bimetallic aluminum complexes and their respective transition metal complexes. We report the experimental reactivity of the LTM complexes that contain a docking group for alkylaluminum or haloaluminum. Syntheses of these complexes follow a ligand first approach, where the LTM complex is first synthesized and isolated, followed by the addition of the aluminum moiety. This synthetic route has been successful in the development of several bimetallicaluminum complexes synthesized by the Brewster lab. We report the reactivity of the aluminum complexes with small molecules (i.e. H2, CO2, etc.). Varying the docking substituent attached to the aluminum moiety provides different reactivity. Experimental and computational investigation of the activation of CO2 are reported.

Comments

Data is provided by the student.

Library Comment

Dissertation or thesis originally submitted to ProQuest

Notes

embargoed

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