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Unimolecular Solvolyses in Ionic Liquid: Alcohol Dual Solvent Systems
A study was undertaken of the solvolysis of pivaloyl triflate in a variety of ionic liquid:alcohol solvent mixtures. The solvolysis is a k(Δ) process (i.e., a process in which ionization occurs with rearrangement), and the resulting rearranged carbocation intermediate reacts with the alcohol cosolve...
Autores principales: | , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
MDPI
2016
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6273061/ https://www.ncbi.nlm.nih.gov/pubmed/26751434 http://dx.doi.org/10.3390/molecules21010060 |
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author | Kochly, Elizabeth D. Lemon, Nicole Jean Deh-Lee, Anne Marie |
author_facet | Kochly, Elizabeth D. Lemon, Nicole Jean Deh-Lee, Anne Marie |
author_sort | Kochly, Elizabeth D. |
collection | PubMed |
description | A study was undertaken of the solvolysis of pivaloyl triflate in a variety of ionic liquid:alcohol solvent mixtures. The solvolysis is a k(Δ) process (i.e., a process in which ionization occurs with rearrangement), and the resulting rearranged carbocation intermediate reacts with the alcohol cosolvent via two competing pathways: nucleophilic attack or elimination of a proton. Five different ionic liquids and three different alcohol cosolvents were investigated to give a total of fifteen dual solvent systems. (1)H-NMR analysis was used to determine relative amounts of elimination and substitution products. It was found, not surprisingly, that increasing the bulkiness of alcohol cosolvent led to increased elimination product. The change in the amount of elimination product with increasing ionic liquid concentration, however, varied greatly between ionic liquids. These differences correlate strongly, though not completely, to the Kamlet–Taft solvatochromic parameters of the hydrogen bond donating and accepting ability of the solvent systems. An additional factor playing into these differences is the bulkiness of the ionic liquid anion. |
format | Online Article Text |
id | pubmed-6273061 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2016 |
publisher | MDPI |
record_format | MEDLINE/PubMed |
spelling | pubmed-62730612018-12-28 Unimolecular Solvolyses in Ionic Liquid: Alcohol Dual Solvent Systems Kochly, Elizabeth D. Lemon, Nicole Jean Deh-Lee, Anne Marie Molecules Article A study was undertaken of the solvolysis of pivaloyl triflate in a variety of ionic liquid:alcohol solvent mixtures. The solvolysis is a k(Δ) process (i.e., a process in which ionization occurs with rearrangement), and the resulting rearranged carbocation intermediate reacts with the alcohol cosolvent via two competing pathways: nucleophilic attack or elimination of a proton. Five different ionic liquids and three different alcohol cosolvents were investigated to give a total of fifteen dual solvent systems. (1)H-NMR analysis was used to determine relative amounts of elimination and substitution products. It was found, not surprisingly, that increasing the bulkiness of alcohol cosolvent led to increased elimination product. The change in the amount of elimination product with increasing ionic liquid concentration, however, varied greatly between ionic liquids. These differences correlate strongly, though not completely, to the Kamlet–Taft solvatochromic parameters of the hydrogen bond donating and accepting ability of the solvent systems. An additional factor playing into these differences is the bulkiness of the ionic liquid anion. MDPI 2016-01-06 /pmc/articles/PMC6273061/ /pubmed/26751434 http://dx.doi.org/10.3390/molecules21010060 Text en © 2016 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons by Attribution (CC-BY) license (http://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Article Kochly, Elizabeth D. Lemon, Nicole Jean Deh-Lee, Anne Marie Unimolecular Solvolyses in Ionic Liquid: Alcohol Dual Solvent Systems |
title | Unimolecular Solvolyses in Ionic Liquid: Alcohol Dual Solvent Systems |
title_full | Unimolecular Solvolyses in Ionic Liquid: Alcohol Dual Solvent Systems |
title_fullStr | Unimolecular Solvolyses in Ionic Liquid: Alcohol Dual Solvent Systems |
title_full_unstemmed | Unimolecular Solvolyses in Ionic Liquid: Alcohol Dual Solvent Systems |
title_short | Unimolecular Solvolyses in Ionic Liquid: Alcohol Dual Solvent Systems |
title_sort | unimolecular solvolyses in ionic liquid: alcohol dual solvent systems |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6273061/ https://www.ncbi.nlm.nih.gov/pubmed/26751434 http://dx.doi.org/10.3390/molecules21010060 |
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