Part one describes a systematic study of the diastereoselectivity of the kinetic Michael addition of ester, ketone and amide enolates to $\alpha$-(sulfinyl)butenolides. Numerous examples of high facial selectivity of $\alpha$-(t-butylsulfinyl)butenolide towards enolates have been discovered, and the factors that influence this selectivity were examined. The structure of the major adduct of the Michael addition of the lithium enolate of methyl acetate to $\alpha$-(t-butylsulfinyl)butenolide was solved by single crystal X-ray crystallography. The results indicate that the facial selectivity of $\alpha$-(sulfinyl)butenolides is determined by the orientation and the size of the sulfinyl group. The sulfur-oxygen bond of the sulfinyl group is antiperiplanar to the carbonyl group of the butenolide in the transition state. / Part two describes an efficient partial synthesis of the antitumor drug taxol. The synthetic equivalent of the taxol side chain precursor, optically pure (+)-3(R)-hydroxy-4(S)-phenyl-2-azetidinone, was obtained via either chemical resolution of racemic $\beta$-lactam or by an efficient asymmetric synthesis from the readily available and recyclable chiral auxiliary 4(R)-phenyloxazolidone. The first example of formation and reaction of a lithium enolate in dichloromethane solvent was discovered. The identity and stability of lithium hexamethyldisilazide in dichloromethane, as well as the reactivity of n-butyllithium in dichloromethane, were examined. N-Benzoyl-$\beta$-lactams were found to undergo DMAP-catalyzed rearrangement to oxazinone. In the presence of DMAP, N-benzoyl-3(R)-(1-ethoxyethoxy)-4(S)-phenyl-2-azetidinone and the corresponding oxazinone reacted with 7-TES-baccatin III to give, after deprotection, a high yield of taxol. / Source: Dissertation Abstracts International, Volume: 54-12, Section: B, page: 6209. / Major Professor: Robert A. Holton. / Thesis (Ph.D.)--The Florida State University, 1991.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_77074 |
| Contributors | Liu, Jyanwei Henry., Florida State University |
| Source Sets | Florida State University |
| Language | English |
| Detected Language | English |
| Type | Text |
| Format | 500 p. |
| Rights | On campus use only. |
| Relation | Dissertation Abstracts International |
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