Ligand Design and Reactivity of Pnictogen Pincer Complexes
| dc.contributor.author | Kirsch, Tamina | |
| dc.contributor.copyright-release | Yes | |
| dc.contributor.degree | Master of Science | |
| dc.contributor.department | Department of Chemistry | |
| dc.contributor.ethics-approval | Not Applicable | |
| dc.contributor.external-examiner | n/a | |
| dc.contributor.manuscripts | Yes | |
| dc.contributor.thesis-reader | Charles Macdonald | |
| dc.contributor.thesis-reader | Alex Veinot | |
| dc.contributor.thesis-supervisor | Saurabh S. Chitnis | |
| dc.date.accessioned | 2025-04-29T12:19:49Z | |
| dc.date.available | 2025-04-29T12:19:49Z | |
| dc.date.defence | 2025-04-09 | |
| dc.date.issued | 2025-04-24 | |
| dc.description | This thesis discusses the design of pincer ligands as a tool to modify the reactivity of planar pnictogen pincer complexes. Computational and experimental methods were explored with the goal of deepening our understanding of pnictogen pincer complexes and the unique interplay of the ligand and the central pnictogen. A theoretical study of 64 different pnictogen pincer complexes explored the impact of the ligand framework on the steric and electronic properties of pincer complexes. The Lewis acidity was investigated by calculating fluoride ion affinity values and comparing the shape and energy of the frontier molecular orbitals of the complexes. The steric properties were investigated by calculating the percent buried volume and assessing the distribution of steric bulk using topographic maps. Trends which help explain and predict the reactivity and properties of pnictogen-based pincer ligands were observed by looking at both the steric and electronic properties. A new class of sterically demanding NCN pincer ligands featuring benzylic methyl groups was developed. Although the targeted planar bismuth pincer complex based on these ligand frameworks was not accessible, the study provided valuable insights into the properties of such bulky ligand systems. The impact of the incorporation of methyl groups into the ligand backbone on the reactivity was investigated in detail both by experimental and computational means. Even small modifications of the ligand backbone can have a significant impact on the reactivity of pincer ligands which can help directing the future design of ligands. In the Future Works section, the synthesis of a library of phosphinimine-based pincer ligands and their potential application to stabilize and easily tune monomeric bismuthinidene compounds is discussed. A novel pyrrole-based bidentate bismuth complex is synthesized and its ability to selectively oxidize the amino side arms of the ligand to imines is investigated. The findings of this thesis deepen our understanding of pnictogen pincer complexes and highlight the impact of the ligand framework by the interplay of molecular and electronic structure. They help not only to explain the reactivity of known compounds, but also to predict reactivity of unknown complexes, thus identifying potential complexes as future targets. | |
| dc.description.abstract | This thesis discusses the design of ligands as a tool to modify the reactivity of planar pnictogen pincer complexes. Computational and experimental methods were explored with the goal of deepening our understanding of the unique interplay of the ligand and the central pnictogen. A theoretical study of 64 different pnictogen pincer complexes explored the impact of the ligand framework on the steric and electronic properties of pincer complexes and revealed trends which help explain the reactivity of pnictogen-based pincer ligands. A new class of sterically demanding NCN pincer ligands featuring benzylic methyl groups was developed which provides valuable insights into the properties of such bulky ligand systems. The findings of this thesis deepen our understanding of pnictogen pincer complexes. They help not only to explain the reactivity of known compounds, but also to predict reactivity of unknown complexes, thus identifying potential complexes as future targets. | |
| dc.identifier.uri | https://hdl.handle.net/10222/85063 | |
| dc.language.iso | en | |
| dc.subject | ligand design | |
| dc.subject | inorganic chemistry | |
| dc.subject | pincer ligands | |
| dc.subject | pnictogens | |
| dc.title | Ligand Design and Reactivity of Pnictogen Pincer Complexes |