Master of Science by Research
Department of Chemistry - Faculty of Science
Mao, Qin Yong, Studies on the L-proline catalyzed and the borono Mannich reaction, MSc-Res thesis, Department of Chemistry, University of Wollongong, 2007. http://ro.uow.edu.au/theses/28/
This thesis describes the results of two independent research projects. The first project is concerned with the synthesis of chiral 1,2-amino alcohols using an organocatalysed Mannich reaction. Chapter 1 gives an overview of L-proline catalysed Mannich reactions and describes the aims of this project. Chapter 2 reports the results of this study. These reactions were found to be low yielding and poorly diastereoselective with the model compound propanal and did not work with the desired aldehyde O-benzylglycosaldehyde. The stereochemical outcomes of these reactions using NMR analysis were not certain. Future work would require X-ray crystallographic studies to confirm the product relative stereochemistries. This project was thus abandoned and a second project was studied. Chapter 3 provides an overview of cyclic N-acyliminium ion chemistry. Chapter 4 describes the results of a study of the borono-Mannich reaction on N-acyliminium ions, generated in situ from hemi-aminals derived from chiral 5-hydroxypyrrolidin-2-ones, to prepare substituted pyrrolidinones. The reactions of these N-acyliminium ions with boronic acids and other nucleophiles can afford the corresponding substituted pyrrolidinones diastereoselectively. The stereochemical assignments of these products were based on NMR coupling constants. X-ray structures of these compounds would be required in the future to confirm these assignments. The success of these reactions provided a possible strategy for the synthesis of functionalized pyrrolidinones and other potential glycosidases inhibitors.
02Whole.pdf (1068 kB)