Croatica Chemica Acta, Vol. 65 No. 3, 1992.
Original scientific paper
The Nature of Nucleophilic Assistance to Ion-Pair Formation. Solvolyses of Cyclohexyl p-Toluenesulfonate
Dennis N. Kevill
; Department of Chemistry, Northern Illinois University, DeKalb, IL 60115
Mohamad H. Abduljaber
; Department of Chemistry, Northern Illinois University, DeKalb, IL 60115
Abstract
The solvolysis of cyclohexyl tosylate has been shown previously both to proceed with nucleophilic assistance from the solvent and to give among the substitution and elimination products those which involve a 1,2-hydride shift. In the present report, specific rate data for solvolysis in 18 solvents at 25.0 °C are shown to give an excellent correlation, using the two-term Grun- wald-Winstein equation, against NT solvent nucleophilicity values and YoTs solvent ionizing power values, with an l value of 0.35 and a m value of 0.85. This indicates that sensitivities to changes in solvent nucleophilicity (Z values) of as large as 0.35 can reflect nucleophilic solvation of a developing carbocation, rather than bimolecular (SN2 + E2) attack. The temperature dependencies of the Z and m values are given consideration.
Keywords
Hrčak ID:
137114
URI
Publication date:
15.10.1992.
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