Carbon and Chlorine Kinetic Isotope Effects and Solvent Effects on the Hydrolysis of Chloroformates

• Autorzy: Swanson S. , Rudziński J. , Paneth P. , O'Leary M. H.
• Języki publikacji: EN

Abstrakty

EN

Carbon and chlorine kinetic isotope effects and pseudo-first order rate constants were measured for the hydrolysis of ethyl, benzyl, and isopropyl chloroformate in various mixtures of the binary solvent water-1,4-dioxane. Rate constants decreased as the percentage of 1,4-dioxane increased for all three chloroformates. Carbon-13 kinetic isotope effects (k12/k13) for hydrolysis of these compounds were 1.039-1.042 for ethyl chloroformate (0-75% 1,4-dioxane), 1.034-1.039 for benzyl chloroformate (15-75% 1,4-dioxane), and 1.025-1.037 for isopropyl chloroformate (25-75% 1,4-dioxane). Chlorine-37 kinetic isotope effects (k35/k37) were measured for benzyl and isopropyl chloroformates in 25% 1,4-dioxane (1.0088, benzyl; 1.0080 isopropyl) and 75% 1,4-dioxane (1.0090, benzyl; 1.0102 isopropyl). These data are consistent with an associative mechanism for benzyl and ethyl chloroformates, but hydrolysis of isopropyl chloroformate appears to be dissociative in polar solvents.

Słowa kluczowe

EN

kinetic isotope effect; reaction mechanism; chloroformates

• Wydawca: Polskie Towarzystwo Chemiczne
• Czasopismo: Polish Journal of Chemistry
• Rocznik: 2002
• Tom: Vol. 76 / nr 12
• Strony: 1721--1731
• Opis fizyczny: Bibliogr. 18 poz., rys.

Twórcy

autor

Swanson S.

• Department of Biochemistry, The Beadle Center, University of Nebraska-Lincoln, Lincoln, NE 68588-0664, USA

autor

Rudziński J.

• Department of Chemistry (1-19), Technical University of Łódź, Żeromskiego 116, 90-924 Łódź, Poland

autor

Paneth P.

• Department of Chemistry (1-19), Technical University of Łódź, Żeromskiego 116, 90-924 Łódź, Poland

autor

O'Leary M. H.

• Department of Biochemistry, The Beadle Center, University of Nebraska-Lincoln, Lincoln, NE 68588-0664, USA

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