Solvolysis of 2-(trifluoromethyl)-2-propyl trifluoromethanesulfonate. Solvent, salt, and. beta. -deuterium isotope effects. Substituents effect of a strongly deactivating group and rate-limiting solvent-assisted elimination
Solvolysis rates of 2-(trifluoromethyl)-2-propyl trifluoromethanesulfonate (2c) in a variety of solvents did not show a correlation with rates for 2-adamantyl tosylate in the same solvents. The effect of added salts on the rates of 2c and 2-propyl tosylate in 80% EtOH was very similar, with significant rate increases for nucleophilic/basic salts. Methyl CD/sub 3/ isotope effects on the rate of 2c in three solvents showed average values k(d/sub 0/)/k(d/sub 3/) = 1.78 and k(d/sub 0/)/k(d/sub 6/) = 3.80. The initial observed product from 2c was CF/sub 3/C(CH/sub 3/)=CH/sub 2/ (4) in all cases. The rate ratio k(i-PrOTf)/k(2c) ranges from a high of 4 x 10/sup 6/ in TFA to a low of 1.5 x 10/sup 4/ in EtOH and shows a high degree of destabilization of a cationic transition state by the CF/sub 3/ group. The results are interpreted in terms of rate-limiting solvent or salt attack on an intimate ion pair formed from 2c. The observed average product ratio CF/sub 3/C(CD/sub 3/)=CH/sub 2//CF/sub 3/C(CH/sub 3/)=CD/sub 2/ of 1.9 from 2c-d/sub 3/ in CF/sub 3/CO/sub 2/D, HFIP, and CD/sub 3/CO/sub 2/D is consistent with this conclusion.
- Research Organization:
- Univ. of Toronto, Scarborough College, Ontario
- OSTI ID:
- 6206209
- Journal Information:
- J. Am. Chem. Soc.; (United States), Vol. 103:13
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
DEUTERIUM
ISOTOPE EFFECTS
ORGANIC FLUORINE COMPOUNDS
SOLVOLYSIS
SULFONIC ACID ESTERS
ACETATES
ACETIC ACID
CHEMICAL REACTION KINETICS
ETHANOL
EXPERIMENTAL DATA
FORMIC ACID
SODIUM CHLORIDES
SODIUM COMPOUNDS
SODIUM PERCHLORATES
ALCOHOLS
ALKALI METAL COMPOUNDS
CARBOXYLIC ACID SALTS
CARBOXYLIC ACIDS
CHEMICAL REACTIONS
CHLORIDES
CHLORINE COMPOUNDS
DATA
DECOMPOSITION
ESTERS
HALIDES
HALOGEN COMPOUNDS
HYDROGEN ISOTOPES
HYDROXY COMPOUNDS
INFORMATION
ISOTOPES
KINETICS
LIGHT NUCLEI
MONOCARBOXYLIC ACIDS
NUCLEI
NUMERICAL DATA
ODD-ODD NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC SULFUR COMPOUNDS
OXYGEN COMPOUNDS
PERCHLORATES
REACTION KINETICS
STABLE ISOTOPES
400301* - Organic Chemistry- Chemical & Physicochemical Properties- (-1987)
400302 - Organic Chemistry- Isotope Effects- (-1987)