Naslov
Heterolytic reactivity of carbonates

Autori
Mirela Matić, Bernard Denegri, Olga Kronja

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

Izvornik
X. Susret mladih kemijskih inženjera - Knjiga sažetaka / - Zagreb : Fakultet kemijskog inženjerstva i tehnologije Sveučilišta u Zagrebu, 2014, 163-163

ISBN
978-953-6470-65-5

Skup
X. Susret mladih kemijskih inženjera

Mjesto i datum
Zagreb, Hrvatska, 20.02.2014. - 21.02.2014

Vrsta sudjelovanja
Poster

Vrsta recenzije
Nije recenziran

Ključne riječi
karbonati; SN1; nukleofugalnost; solvoliza; DFT
(carbonate; SN1; nucleofugality; solvolysis; DFT)

Sažetak
Similarly as carboxylate esters, carbonates solvolyze in a weakly basic and neutral medium via SN1 mechanism if stabilized carbocation intermediate is produced in the heterolytic step.Under these conditions heterolytic reactivities (nucleofugalities) of carbonate leaving groups determine reaction rates according to the LFER Equation (1).-log k (25 °C) = sf (Nf + Ef)(1)- In this correlation equation k is the solvolysis first-order rate constant, sf (slope of the correlation line) and Nf (negative intercept on the abscissa) are the nucleofuge specific parameters, whereas Ef represents the electrofugality parameter of variously substituted benzhydrylium electrofuges. Solvolytic first-order rate constants have been measured for various benzhydryl carbonates and nucleofugality parameters of some carbonate leaving groups have been determined according to Equation (1). Additionaly, the applicability of quantum-chemical model reaction (IEFPCM M06-2X/AUG-cc-pVDZ level), which includes cyclopropyl ring opening with simultaneous heterolytic displacement of the carbonate leaving group, has been examined for determination of Nf parameters of carbonates. On the basis of the good correlation between experimental and calculated data it is possible to extend the nucleofugality scale significantly.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

POVEZANOST RADA