Isotope Rate Effects in the Enolization of Oxalacetic Acid
Acid-catalyzed enolization of oxalacetic ncid in H/sub 2/O and D/sub 2/O gives rise to a constant isotope rate effect k/sub H/sub 2/O/ /k/sub D /sub 2/O of 2.4 over the pH (pD) range of 5 5 to 7.5. Base-catalyzed enolization of oxalacetic acid in H/sub 2/O and D/sub 2/O gives rise to a constant isotope rate effect k/sub H/sub 2/O/k/sub D/sub 2/O of 4.5 over th e pH (pD) range of 7.0 to 8.0. The percentage of enol form of oxalacetic acid was calculated to be 15.3% at pH 8.0, using the absorption of the enol form in ether at 255 m mu and the absorption of the keto form at pH 0.5 in an aqueous system. The spectrophotometric measurement of the isotope rate effect involved in the enolization of oxalacetic acid gives direct evidence for the rate-determining step in both the acid- and the base-catalyzed reactions without subsequent reactions.
- Research Organization:
- Univ. of Windsor, Ont.
- Sponsoring Organization:
- USDOE
- NSA Number:
- NSA-16-023532
- OSTI ID:
- 4830446
- Journal Information:
- Canadian Journal of Chemistry, Journal Name: Canadian Journal of Chemistry Journal Issue: 7 Vol. 40; ISSN 0008-4042
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
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