Croatica Chemica Acta, Vol. 83 No. 2, 2010.
Short communication, Note
Reactivity of Acetates in Aqueous Alcohols
Bernard Denegri
; Faculty of Pharmacy and Biochemistry, University of Zagreb, Ante Kovačića 1, 10000 Zagreb, Croatia
Olga Kronja
; Faculty of Pharmacy and Biochemistry, University of Zagreb, Ante Kovačića 1, 10000 Zagreb, Croatia
Abstract
A series of X,Y-substituted benzhydryl acetates (1-3) were subjected to solvolysis in various binary methanol/water and ethanol/water mixtures at 25 °C. The LFER equation log k = sf(Ef + Nf) was used
to derive the nucleofuge-specific parameters (Nf and sf) for an SN1 type reaction in 60 % and 80 % aqueous methanol. It has been established that X,Y-substituted benzhydryl acetates produce almost parallel correlation lines, so the average sf = 0.9 has been taken for calculation of the nucleofugality parameters
from a single rate constant in some solvent mixtures. In comparison with other leaving groups for which
the nucleofugality has already been determined, acetates are the poorest nucleofuges.
Keywords
acetate; nucleofugality; electrofugality; solvolysis; nucleophilic substitution
Hrčak ID:
56026
URI
Publication date:
15.7.2010.
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