Naslov
Solvolytic Reactivity of Pentafluorophenolates

Autori
Matić, Mirela ; Denegri, Bernard ; Bebek, Nives ; Kronja, Olga

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
25. Hrvatski skup kemičara i kemijskih inženjera s međunarodnim sudjelovanjem - Knjiga sažetaka / - , 2017, 106-106

Skup
25. Hrvatski skup kemičara i kemijskih inženjera

Mjesto i datum
Poreč, Hrvatska, 19.04.2017. - 22.04.2017

Vrsta sudjelovanja
Poster

Vrsta recenzije
Nije recenziran

Ključne riječi
reactivity, nucleofugality, pentafluorophenolate, solvolysis, intrinsic barrier

Sažetak
The reactivity (nucleofugality) of the pentafluorophenolate leaving group has been determined experimentally from first order solvolytic rate constants (k) of X, Y-substituted benzhydryl pentafluorophenolates by using three-parameter LFER equation: log k = sf(Ef + Nf) (1). The parameters in this equation are: the nucleofuge-specific parameters Nf (the negative intercept on the abscisa of the log k/Ef correlation line) and sf (the slope of the correlation line), and Ef, the electrofugality parameter – an independent variable that quantifies the solvolytic reactivity of a certain electrofuge. Comparison with nucleofugalities of other leaving groups reveals that pentafluorophenolate is a moderate leaving group (Nf = –0.97 in 80% aqua ethanol) with an unusually high reaction constant (sf = 1.29 for 80% ethanol). Besides the main purposes of estimating solvolytic reactivities of various substrates and comparing reactivity of leaving groups in a wide range of reactivity, equation (1) can also be employed in investigating the solvolytic behavior of various types of substrates and leaving groups. Thus, it enables to observe variation and even inversion in relative reactivities of phenolates and carboxylates due to different reactivity of electrofuges. Furthermore, correlation of Δ‡G°/ΔrG° for solvolysis of benzhydryl phenolates and carboxylates indicates that phenolates solvolyze over the lower Marcus intrinsic barrier than corresponding carboxylates.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

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