Date of Award


Publication Type

Doctoral Thesis

Degree Name



Chemistry and Biochemistry


Pure sciences, Oxidation states, Indium compounds, Diimine, Halides


Macdonald, Charles L. B.




The work described herein focuses on the chemistry of low oxidation state indium salts. Indium in its +1 oxidation state is electron rich, as it possesses a "lone pair" of electrons which are capable of undergoing further chemistry, such as oxidative addition and transition metal ligation. One of the main benefits of In(I) compounds is that they are amphoteric and thus capable of acting as both a Lewis acid as well as a Lewis base. One of the major drawbacks in the field of In(I) chemistry, however, is a lack of convenient starting materials. The In(I) halides have very poor solubility in non-donor solvents and readily decompose in the presence of strong donor molecules. The addition of acyclic polyethers to a series of In(I) (and III) salts very rarely resulted in decomposition. Their effect on solubility is investigated and reported. A more soluble indium(I) salt is indium trifluoromethanesulfonate (indium triflate, InOTf). This salt is significantly more stable than its halide counterparts, however it is sometimes too inert and does not react at all. It has been previously reported that the addition of crown ether ligands increase the reactivity of the metal centre and can cause oxidative addition into carbon-chlorine bonds. The effects of various destabilizing ligands is discussed and a computational investigation provides insight into the electronic stability of these ligated systems. The reactivity with InOTf with "non-innocent" α-diimine (DAB) ligands is also investigated. These ligands are capable of undergoing redox chemistry and generating ambiguous metal oxidation states. Substitution patterns on DAB ligands were found to play a major role in the reactivity of InOTf as shown by X-ray crystallography, EPR spectroscopy, cyclic voltammetry and computational analysis.