Desymmetrization by changing hydrophilicity/hydrophobicity
| dc.contributor.committeeChair | Niwayama, Satomi | |
| dc.creator | Mei, Zhong | |
| dc.date.accessioned | 2016-11-14T23:11:51Z | |
| dc.date.available | 2012-06-01T15:24:07Z | |
| dc.date.available | 2016-11-14T23:11:51Z | |
| dc.date.issued | 2011-08 | |
| dc.description.abstract | Desymmetrization of symmetric compounds is a powerful strategy with regards to both asymmetric and nonasymmetric synthesis. When this strategy is applied to hydrolysis of symmetric diesters, the process is called monohydrolysis and half-esters can be produced. Since they are versatile building blocks in organic synthesis, various half-esters are synthesized by monohydrolysis of corresponding diesters in mainly aqueous media. However, the reason why the monohydrolysis we studied has a high selectivity is unknown. In this thesis, dynamic light scattering is employed to analyze possible intermediates of monohydrolysis. The results indicate that a “micelle-like” intermediate is likely to exist in the mainly aqueous media. Based on this mechanism, additional kinds of water-mediated desymmetric reactions are performed by changing hydrophilicity/hydrophobicity to produce “micelle-like” compounds, including mono-oxidation and mono-reduction. As water possesses many ideal characteristics as a reaction medium such as accessibility, environmental safety, and low cost, the development of organic reactions in aqueous media has been of central importance in recent organic chemistry. Since the current reaction of monohydrolysis of symmetric diesters produce racemic mixtures, attempts for enantioselective monohydrolysis is made catalyzed by chiral proline derivatives, chiral ionic liquids and cinchona alkaloids, for the purpose of producing enantiomerically enriched half-esters. | |
| dc.format.mimetype | application/pdf | |
| dc.identifier.uri | http://hdl.handle.net/2346/ETD-TTU-2011-08-1786 | |
| dc.language.iso | eng | |
| dc.rights.availability | Unrestricted. | |
| dc.subject | Desymmetrization | |
| dc.subject | Hydrolysis | |
| dc.subject | Oxidation | |
| dc.subject | Reduction | |
| dc.title | Desymmetrization by changing hydrophilicity/hydrophobicity | |
| dc.type | Thesis |