1. Insights into the mechanisms of asymmetric phase-transfer catalysis
- Author
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Badiola, Katrina Anne and Smith, Martin D.
- Subjects
547 ,Chemistry, Organic - Abstract
This thesis describes work conducted towards the study of the mechanisms of asymmetric cation-directed phase-transfer catalysis (PTC). Chapter 1 introduces the field of PTC, including its general mechanisms, utility in an asymmetric context, and previous kinetic and mechanistic studies. Despite being a well-established technique in organic chemistry, the precise mechanisms of enantioselective phase-transfer reactions, particularly those effected by cinchona alkaloid-derived catalysts are not fully understood. In Chapter 2, we found that studying enantioselective phase-transfer reactions effected by cinchona alkaloid-derived catalysts proved to be both practically and intellectually demanding. The manner in which the reactions were practically conducted had significant bearings on the kinetic behaviour that was exhibited. Primarily, we developed robust methods that enabled the collection of reliable, reproducible kinetic data from polyphasic heterogeneous reaction systems. Chapter 3 describes the kinetic and mechanistic study of a phase-transfer catalysed intramolecular C-acylation reaction. Deconvolution of the mechanism involved a series of practical kinetic investigations, evaluation of theoretical models, and further experimental interrogation. The final mechanistic hypothesis highlighted a series of processes concerning catalyst activation and regeneration, which were rate-determining in this system. Chapter 4 presents a concise summary and conclusion to the thesis, and Chapters 5 to 10 describe experimental details and provide supporting information.
- Published
- 2020