Naslov
Solvolytic Behaviour of Benzyl Halides in Aqueous Ethanol

Autori
Matić, Mirela ; Denegri, Bernard

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

Izvornik
European Symposium on Organic Reactivity 2019 - Book of abstracts / Vančik, Hrvoj ; Namjesnik, Danijel - Zagreb : Hrvatsko kemijsko društvo, 2019, 75-75

ISBN
978-953-55232-9-1

Skup
17th European Symposium on Organic Reactivity (ESOR 2019)

Mjesto i datum
Dubrovnik, Hrvatska, 08.09.2019. - 13.09.2019

Vrsta sudjelovanja
Poster

Vrsta recenzije
Nije recenziran

Ključne riječi
Benzyl halides, solvolysis, Hammett correlation, SN1 and SN2 mechanisms, aqueous ethanol

Sažetak
Previous studies on benzyl sulfonates clearly showed that solvolyses of these aromatic primary substrates proceeded through both SN1 and SN2 mechanisms, which was indicated by either the break or curvature in a Hammett plot. The Hammett treatment of solvolysis rates further indicated that benzyl sulfonates substituted by both strong and weak electron-releasing substituents underwent the monomolecular substitution in aqueous acetone and other solvents of lower nucleophilicity. We have determined rate constants for solvolysis of some benzyl halides in 80% ethanol and employed the Hammett correlation analysis to investigate the influence of substituents on the solvolytic behaviour of benzyl derivatives in a media of higher nucleophilicity. Kinetic results confirm thebreakdown of the linear relationship, i.e., the change in the mechanism of solvolysis within the series. However, unlike data for hydrolysis in aqueous acetone presented in the previous studies, data for solvolysis of alkyl and aryl-substituted benzyl substrates in 80% ethanol do not match the SN1 line, indicating a strong impact of the solvent nucleophilicity on the mechanistic change in the series. Additional measurements have been carried out to ascertain whether or not the alkyl and aryl-substituted benzyl halides react by the concerted bimolecular mechanism exclusively. Although a simple Hammett analysis suffers from serious flaws, it still represents an applicable tool for detecting the change of mechanism in a series of related substrates.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

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