Studies in synthesis using CO2 and H2 gases

dc.check.date2027-09-30
dc.contributor.advisorMcglacken, Gerard P.
dc.contributor.advisorByrne, Peter
dc.contributor.authorLowry, Amyen
dc.contributor.funderIrish Research Council
dc.contributor.funderHigher Education Authority
dc.date.accessioned2024-06-12T14:58:26Z
dc.date.available2024-06-12T14:58:26Z
dc.date.issued2023
dc.date.submitted2023
dc.description.abstractThis thesis is split into two parts based on two different areas of research. Part 1 Part 1 is sub-divided into four chapters. Chapter 1 involves a review of the existing research conducted in this area. Chapter 2 provides details on the research carried out in this project on the development of a Wittig CO2 utilisation methodology for the synthesis of α,β unsaturated carboxylic acids. Chapter 3 involves discussion on the development of protocols for purification of the α,β-unsaturated carboxylic acids synthesised. The Conclusions and Future Work section relating to this area of research is found at the end of Chapter 3. Chapter 4 outlines the experimental work for Part 1. CO2 utilisation continues to capture the attention of chemists due to the ever-increasing levels of CO2 and the negative effects of global warming. CO2 is an inexpensive and environmentally friendly C1 building block, which can be used in the synthesis of value-added chemicals. Many medicinally important compounds and natural products contain the elements of CO2 within their structure, including carboxylic acids, enoates, and carbamates. In particular, α,β unsaturated carboxyl compounds are typically accessed by metal-catalysed transformations or condensation reactions, which often require hydrolysis of the ester product to furnish the corresponding acid. In this project, a telescoped process was developed, that not only achieves CO2 activation, but exploits a novel application of the Wittig reaction, enabling direct installation of the carboxyl group by two successive carbon-carbon bond forming events. Reaction optimisation and purification studies were carried out and 34 α,β-unsaturated carboxylic acids were synthesised using the method, containing a wide range of functional groups, as well as a number of pharmaceutical precursors, in moderate to excellent yields. As part of this work, a novel method for purification of α,β-unsaturated carboxylic acids was developed. Part 2 Part 2 is sub-divided into three chapters. Chapter 5 involves a discussion on the background of the project and a review of the existing research conducted in the area. Chapter 6 involves a discussion of the research carried out in this project on the dearomatisation of benzofuroquinolines by a Pd-catalysed hydrogenation reaction. The Conclusions and Future Work section relating to this part of the thesis is found at the end of Chapter 6. Chapter 7 outlines the experimental work for Part 2. Within the McGlacken group, development of C-H activation methodologies has been a large area of research, and, in particular, benzofuroquinolines have been synthesised via direct intramolecular arylation of 4-phenoxyquinolines. The quinoline nucleus is one of the most frequently occurring ring systems in approved drugs, and hydrogenation of the quinoline nucleus and the selectivity thereof, has been reported in the literature. In addition, increasing interest in the concept of ‘escaping flatland’, whereby the saturation of compounds is increased, allowing for the exploration of more architecturally complex molecules that will potentially give rise to enhanced biological activities. In this part of the thesis, a range of differently substituted benzofuroquinolines were hydrogenated to generate 18 selectively dearomatised benzofuroquinolines. Investigations were carried out into different reaction conditions tolerated by the reaction, and the fate of halogen substituents in the reaction. In addition, a double reduction product side-product was identified and characterised, opening up the methodology to the formation of a new class of novel compounds.en
dc.description.statusNot peer revieweden
dc.description.versionAccepted Versionen
dc.format.mimetypeapplication/pdfen
dc.identifier.citationLowry, A. 2023. Studies in synthesis using CO2 and H2 gases. PhD Thesis, University College Cork.
dc.identifier.endpage332
dc.identifier.urihttps://hdl.handle.net/10468/16007
dc.language.isoenen
dc.publisherUniversity College Corken
dc.rights© 2023, Amy Lowry.
dc.rights.urihttps://creativecommons.org/licenses/by-sa/4.0/
dc.subjectCarbon dioxide utilisation
dc.subjectWittig reaction
dc.subjectPhosphonium ylide
dc.subjectCarboxylic acid
dc.subjectHydrogenation
dc.subjectDearomatisation
dc.subjectQuinolines
dc.subjectHeterogeneous catalysis
dc.titleStudies in synthesis using CO2 and H2 gases
dc.typeDoctoral thesisen
dc.type.qualificationlevelDoctoralen
dc.type.qualificationnamePhD - Doctor of Philosophyen
Files
Original bundle
Now showing 1 - 3 of 3
Loading...
Thumbnail Image
Name:
LowryAB_PhD2023.docx
Size:
13.54 MB
Format:
Microsoft Word XML
Description:
Full Text E-thesis (Word)
Loading...
Thumbnail Image
Name:
LowryAB_PhD2023.pdf
Size:
13.23 MB
Format:
Adobe Portable Document Format
Description:
Full Text E-thesis
Loading...
Thumbnail Image
Name:
LowryAB_Submission for Examination Form.pdf
Size:
1.27 MB
Format:
Adobe Portable Document Format
License bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
license.txt
Size:
5.2 KB
Format:
Item-specific license agreed upon to submission
Description: