posted on 2018-06-28, 09:12authored byAdel Ardakani
This thesis discusses the field of asymmetric synthesis of oxiranes. An
introduction highlighting the most successful methods for the synthesis of chiral
epoxides including the latest advances in these areas, with particular attention paid to
the organocatalytic techniques is presented in chapter one.
The second chapter begins by summarizing the group's previous efforts in the
initial stage of this project and sets the motif for this work. These include: the
synthesis of enantiopure dihyroisoquinolinium salts with a chiral residue attached to
the exocyclic carbon-nitrogen bond as catalysts for asymmetric epoxidation; utilizing
systems such as camphor and natural amino acids as starting points for these
syntheses; developing other catalyst families in order to delve into the possibility of
eliminating the structural weaknesses leading to loss of enantioselectivity in the
oxygen transfer process; attempts to probe the reactive intermediates responsible for
the asymmetric induction by analytical techniques; checking for catalyst applicability
with different alkene and sulphide substrates; the development of anhydrous reaction
conditions and their testing with the successful catalysts prepared. Enantiomeric
excesses of up to 70% have been obtained. An attempt at exploring the synthesis of
chiral reagents for the asymmetric epoxidation via a Payne/peroxyacid route is also
described. This chapter concludes with a comparison of the catalyst families
generated, and presents a few suggestions for future research in this area.
The third chapter is dedicated to, the experimental section and includes the
methods of synthesis and characterization of the compounds in the results and
discussion chapter.
There are three appendices at the. end of the thesis; Appendix A contains a
summary the X-ray reports regarding the crystallographic data of the compound
structures presented in chapter two. Appendix B contains samples of the analytical
spectra of the enantiomeric excess determination for epoxides. Appendix C includes a copy of both publications I was involved in during my research in this topic.
Funding
Loughborough University. [EPSRC and] AstraZeneca plc (CASE Award Studentship).
This work is made available according to the conditions of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/4.0/
Publication date
2002
Notes
A Doctoral Thesis. Submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy at Loughborough University.
This Thesis includes of copies of separate publications. It has been redacted for reasons relating to the law of copyright. For more information please contact the author.