Defining the role of partially covalent weak interactions in chemical reactions
department or school: Science, Faculty of
department or school: Chemistry, Department of
data provider: DSpace
degree campus: UBCV
creator: Tong, Xing
issued: 2023-09-30T07:00:00Z
issued: 2022
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: Weak interactions, commonly known as secondary bond interactions (SBIs), have received far less attention than their stronger counterparts (i.e., primary bonds, e.g., ionic, metallic, and covalent bonds). The most mainstream perspective is that those interactions are induced by the attraction between partially positive and partially negative areas on molecular surfaces. This electrostatics-driven model has been widely accepted as it is straightforward, intuitive, and widely applicable; however, more and more computational and experimental discoveries have thrown this “simple and practical” theory into question. Other quantum chemical effects like charge transfer cannot be ignored if a generalized picture of weak interactions is required. Due to the relatively weak bond strengths, it is often difficult to study weak interactions exclusively and accurately. With synchrotron X-ray absorption spectroscopy (XAS) in combination with different computational methods, the nature of two common weak interactions (i.e., halogen bonding XB and chalcogen bonding ChB) has been comprehensively investigated. To begin with, two types of model systems (i.e., hypervalent halogen salts and bis-triazole-pyridinium series) were chosen to study the degree of charge transfer in XB and ChB. These studies have given evidence for a substantial degree of covalent contribution in both XB and ChB interactions. The relevance of such interactions in modulating chemical processes has also been explored. For example, the significance of the charge transfer component in XB was confirmed in a catalyzed Ritter-like process (carbon-halogen bond cleavage). We have further demonstrated the important role of ChB in processes ranging from petroleum-coke modification to pharmaceutical drug synthesis. The obtained data has shown that both XBs and ChBs should be considered as partially covalent interactions and the covalent contributions can be tuned by the properties of involved electron donor/acceptor pairs. …
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/82549
note: DEFINING THE ROLE OF PARTIALLY COVALENT WEAK INTERACTIONS IN CHEMICAL REACTIONS by Xing Tong B.E., South China University of Technology, 2017 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES (Chemistry) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) August 2022 © Xing Tong, 2022 ii The following individuals certify that they have read, and recommend to the Faculty of Graduate and Postdoctoral Studies for acceptance, the dissertation entitled: Defining the Role of Partially Covalent Weak Interactions in Chemical Reactions submitted by Xing Tong in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Chemistry Examining Committee: Dr. Suzana Straus, Professor, Department of Chemistry, UBC Co-supervisor Dr. Pierre Kennepohl, Professor, Department of Chemistry, UBC/University of Calgary Co-supervisor Dr. Chris Orvig, Professor, Department of Chemistry, UBC Supervisory Committee Member Dr. Grenfell Patey, Professor, Department of Chemistry, UBC University Examiner Dr. Mark Thachuk, Associate Professor, Department of Chemistry, UBC University Examiner Additional Supervisory Committee Members: Dr. Curtis Berlinguette, Professor, Department of Chemistry, UBC Supervisory Committee Member iii Abstract Weak interactions, commonly known as secondary bond interactions (SBIs), have received far less attention than their stronger counterparts (i.e., primary bonds, e.g., ionic, metallic, and covalent bonds). The most mainstream perspective is that those interactions are induced by the attraction between partially positive and partially negative areas on molecular surfaces. This electrostatics-driven model has been widely accepted as it is straightforward, intuitive, and widely applicable; however, more and more computational and experimental discoveries have thrown this “simple and practical” theory into question. Other quantum chemical effects like c…
has type: Thesis/Dissertation
date issued: 2022-11
is shown at: 10.14288/1.0417565
language: eng
degree discipline: Chemistry
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
contributor: Straus, Suzana
contributor: Kennepohl, Pierre
type: Text
identifier URI: http://hdl.handle.net/2429/82549