ISSN:
0894-3230
Schlagwort(e):
nucleophilic substitution reactions
;
cycloalkylmethyl arenesulfonates
;
positive ρXZ values
;
secondary kinetic isotope effects
;
Chemistry
;
Theoretical, Physical and Computational Chemistry
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
,
Physik
Notizen:
---Nucleophilic substitution reactions of cycloalkylmethyl arenesulfonates (CmH2n-1CH2OSO2C6H4Z) with anilines (XC6H4NH2) in methanol at 65.0 °C were studied. The reactivity order (n=4〉6〉7〉5) reflects largely the order of steric effect of the ring size (SEs term) except for n=5, which exhibits the least reactivity. This reversal of the order for n=5 is considered to result from large rate retardation due to polar effect of the ρ*σ* term. Application of the Taft equation to the rate data for n=5 and 6 gives ρ*=17·4 and S=2·3 with correlation coefficient of 0·90. The σ* values for n=4 and 7 are estimated to be -0·23 and -0·11, respectively. The positive ρXZ values of ca 0·3 are consistent with previous results for the reactions at primary reaction centers. © 1997 by John Wiley & Sons, Ltd.
Zusätzliches Material:
6 Tab.
Materialart:
Digitale Medien
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