Experimental and theoretical studies of acid-catalyzed oxygen-18 exchange rates of conformationally rigid ketones. Is the antiperiplanar effect important?
Autor: | K. N. Houk, Fanzuo Kong, Yun Dong Wu, Robert R. Fraser, Maria Stanciulescu |
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Rok vydání: | 1993 |
Předmět: | |
Zdroj: | The Journal of Organic Chemistry. 58:4431-4440 |
ISSN: | 1520-6904 0022-3263 |
DOI: | 10.1021/jo00068a044 |
Popis: | The relative rates for the acid-catalyzed addition of H 2 18 O to the carbonyl group of the conformationally fixed bridged biaryl ketone, 1, and several derivatives bearing methyl, chloro, and methoxy substituents in axial-like and equatorial-like orientations have been measured. The effects of axial- versus diaxiallike methyl and chloro substituents produce rate decreases which are consistentwith the antiperiplanar (hyperconjugative) interaction proposed by Cieplak; however, the negligible influence of a methoxy group when antiperiplanar is not consistent |
Databáze: | OpenAIRE |
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