Synthesis and Reactivity of a Bulky Indium Anion
The research presented in this master’s thesis focuses on the synthesis and reactivity of N–heterocyclic indium anions – indyl anions, specifically ([In(XNONTCHP)] , (XNON = 4,5– bis(2,6–diisopropylanilido)–2,7–di–tert–butyl–9,9–dimethylxanthene, TCHP = 2,4,6– tricyclohexyl phenyl). These indyl anions, which feature the XNON ligand with N–substituents bearing the TCHP group are charge balanced with a potassium cation. The study of anionic indium(I) complexes has gained significant attention in the past five years due to their nucleophilic properties and versatile reactivity patterns. This research contributes to the rapidly developing field of anionic indium chemistry, exploring the synthesis and reactivity of new indyl anions.
Chapter One provides a literature review on the synthesis of the first low–valent group 13 complexes, followed by a detailed review of the first anionic group 13 complexes with a considerable focus on the heavier analogues. We discuss the synthetic strategies employed to obtain these anionic complexes, highlighting the ligand systems and reducing agents used in their preparation. The review also discusses their structural features, including bond lengths, angles, and coordination geometries, as determined by single crystal X–ray crystallography.
Chapter Two broadens the scope of the XNON ligand system, which has been previously synthesised using Dipp N–substituents, by introducing a bulky TCHP substituent. The aim is to enhance the steric properties of the ligand and investigate the impact they will have on the properties of the resulting indyl anion complexes.
Chapter Three expands the existing literature on the chemistry of indium(I) complexes by introducing a new bulky indyl anion. This chapter presents three different synthetic routes that have been developed to obtain three distinct TCHP indyl anions. We discuss how these different indyl anions may differ in stability and reactivity compared to previous literature examples.
Chapter Four focuses on the reactivity studies conducted on the three synthesised TCHP indyl anions. This chapter aims to investigate the reactivity patterns of the indyl anions and evaluate the success of different reactions attempted, as well as any unexpected or interesting findings. The limitations and challenges encountered during the reactivity studies are addressed, highlighting the reactions that did not yield the desired outcomes. The reasons for unsuccessful reactions are analysed, and possible strategies for addressing these challenges in the future are discussed.
