An attempt has been made to develop a model for predicting the course of an asymmetric alkylation. Thus, by considering the influence of an asymmetric center upon a reaction center located in an adjoining plane, a preferred conformation of the intermediate anion is selected. This conformation is used to predict the stereochemistry of the product. The model correctly predicts the stereochemical result of several reactions known in the literature.
The (-) isobornyl and (-) menthyl esters of 2-methylbutyric acid were alkylated with 1-bromobutane in 42% yield. Both of the alkylated esters were reduced with lithium aluminium hydride and the 2-methyl-2-ethylhexan-1-ol isolated by gas-liquid chromatography was shown to be optically inactive. The lack of an observable rotation does not permit a critical evaluation of the proposed model in these instances.
The major impurities present in the alkylation of the aforementioned esters, namely the n-butyl ether of the optically active alcohol, have been identified by independent syntheses. / Science, Faculty of / Chemistry, Department of / Graduate
| Identifer | oai:union.ndltd.org:UBC/oai:circle.library.ubc.ca:2429/38849 |
| Date | January 1963 |
| Creators | Rolston, John Henry |
| Publisher | University of British Columbia |
| Source Sets | University of British Columbia |
| Language | English |
| Detected Language | English |
| Type | Text, Thesis/Dissertation |
| Rights | For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use. |
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