Mechanism of hydrolysis of coumaran-2-ones

David M. Heathcote, Gareth A. De Boos, John H. Atherton, Michael I. Page

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

The hydrolysis of coumaran-2-one and 5-substituted 3-phenylcoumaran-2-ones is preceded by a pre-equilibrium involving the formation of an enolate anion at high pH. The pKa of 3-phenylcoumaran-2-one is 8.39 in water at 25°C and the 3-phenyl substituent increases the carbon acidity by 104. However, despite this ready carbanion formation, the conventional addition-elimination mechanism for hydrolysis of 3-phenylcoumaran-2-ones is confirmed by a solvent kinetic isotope effect of 0.63 and a Brønsted β1g of -0.6. This is compatible with rate limiting formation of a tetrahedral intermediate.

LanguageEnglish
Pages535-540
Number of pages6
JournalJournal of the Chemical Society. Perkin Transactions 2
Issue number3
DOIs
Publication statusPublished - Mar 1998

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Hydrolysis
Acidity
Isotopes
Anions
Carbon
Kinetics
Water
coumaran

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Heathcote, D. M., De Boos, G. A., Atherton, J. H., & Page, M. I. (1998). Mechanism of hydrolysis of coumaran-2-ones. Journal of the Chemical Society. Perkin Transactions 2, (3), 535-540. https://doi.org/10.1039/a707946j
Heathcote, David M. ; De Boos, Gareth A. ; Atherton, John H. ; Page, Michael I. / Mechanism of hydrolysis of coumaran-2-ones. In: Journal of the Chemical Society. Perkin Transactions 2. 1998 ; No. 3. pp. 535-540.
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Mechanism of hydrolysis of coumaran-2-ones. / Heathcote, David M.; De Boos, Gareth A.; Atherton, John H.; Page, Michael I.

In: Journal of the Chemical Society. Perkin Transactions 2, No. 3, 03.1998, p. 535-540.

Research output: Contribution to journalArticle

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