Temperature dependence of bromine kinetic isotope effects for reactions of n-butyl and tert-butyl bromides

Journal Article · Wed Mar 26 04:00:00 EST 1980 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00527a042· OSTI ID:5279691

Willey, J F; Taylor, J W

Techniques for the measurement of bromine leaving group kinetic isotope effects (KIE) are described. Experimental values at 20/sup 0/C for the solvolysis of tert-butyl bromide (0.045 M) in methanol with 0.3 M 2,6-lutidine and for the reaction of n-butyl bromide (0.047 M) with thiophenoxide anion (0.052 M) in 0.25 M lithium methoxide/methanol solvent are 1.003 10 (+-0.000 04) and 1.00l 69 (+-0.000 03), respectively. The natural logarithm of the KIE was found to vary linearly with l/T from 0 to 40/sup 0/C for tert-butyl bromide, slope = 0.472 (+-0.080) deg/sup -1/, and from -10 to 40/sup 0/C for n-butyl bromide, slope = 0.531 (+-0.029) deg/sup -1/. The significance of the KIE temperature dependencies is discussed. 6 tables.

• Research Organization: Univ. of Wisconsin, Madison
• OSTI ID: 5279691
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 102:7; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400302* -- Organic Chemistry-- Isotope Effects-- (-1987)
ALCOHOLS
BROMINATED ALIPHATIC HYDROCARBONS
BROMINE ISOTOPES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
DATA
DECOMPOSITION
EXPERIMENTAL DATA
HALOGENATED ALIPHATIC HYDROCARBONS
HYDROXY COMPOUNDS
INFORMATION
ISOTOPE EFFECTS
KINETICS
MEDIUM TEMPERATURE
METHANOL
NUMERICAL DATA
ORGANIC BROMINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
REACTION KINETICS
SOLVOLYSIS
TEMPERATURE DEPENDENCE