The effect of a hydrogen bond acceptor catalyst on the dimer mechanism in aromatic nucleophilic substitution

The reaction of 2,6-dinitroanisole with cyclohexylamine in toluene-dimethyl sulphoxide (DMSO) mixtures was studied at several amine concentrations. In pure toluene and toluene-DMSO mixtures of low DMSO content (≤ 1%) third-order kinetics with respect to the amine are observed. These results are inte...

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Autores principales: Palleros, D.R., Nudelman, N.S.
Formato: JOUR
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_1472779X_v_n4_p479_Palleros
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Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires
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spelling todo:paper_1472779X_v_n4_p479_Palleros2023-10-03T16:18:01Z The effect of a hydrogen bond acceptor catalyst on the dimer mechanism in aromatic nucleophilic substitution Palleros, D.R. Nudelman, N.S. The reaction of 2,6-dinitroanisole with cyclohexylamine in toluene-dimethyl sulphoxide (DMSO) mixtures was studied at several amine concentrations. In pure toluene and toluene-DMSO mixtures of low DMSO content (≤ 1%) third-order kinetics with respect to the amine are observed. These results are interpreted as a consequence of the aggregation of the nucleophile (dimer) in low-polarity solvents. Association of DMSO with the amine ('mixed dimer') in a solute-solvent hydrogen-bond interaction can be responsible for the observed catalytic effect of DMSO. At higher DMSO contents behaviour typical for amine catalysis was found which is related to considerable additional stabilization of the intermediate complex through solvation by DMSO. Fil:Palleros, D.R. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_1472779X_v_n4_p479_Palleros
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
description The reaction of 2,6-dinitroanisole with cyclohexylamine in toluene-dimethyl sulphoxide (DMSO) mixtures was studied at several amine concentrations. In pure toluene and toluene-DMSO mixtures of low DMSO content (≤ 1%) third-order kinetics with respect to the amine are observed. These results are interpreted as a consequence of the aggregation of the nucleophile (dimer) in low-polarity solvents. Association of DMSO with the amine ('mixed dimer') in a solute-solvent hydrogen-bond interaction can be responsible for the observed catalytic effect of DMSO. At higher DMSO contents behaviour typical for amine catalysis was found which is related to considerable additional stabilization of the intermediate complex through solvation by DMSO.
format JOUR
author Palleros, D.R.
Nudelman, N.S.
spellingShingle Palleros, D.R.
Nudelman, N.S.
The effect of a hydrogen bond acceptor catalyst on the dimer mechanism in aromatic nucleophilic substitution
author_facet Palleros, D.R.
Nudelman, N.S.
author_sort Palleros, D.R.
title The effect of a hydrogen bond acceptor catalyst on the dimer mechanism in aromatic nucleophilic substitution
title_short The effect of a hydrogen bond acceptor catalyst on the dimer mechanism in aromatic nucleophilic substitution
title_full The effect of a hydrogen bond acceptor catalyst on the dimer mechanism in aromatic nucleophilic substitution
title_fullStr The effect of a hydrogen bond acceptor catalyst on the dimer mechanism in aromatic nucleophilic substitution
title_full_unstemmed The effect of a hydrogen bond acceptor catalyst on the dimer mechanism in aromatic nucleophilic substitution
title_sort effect of a hydrogen bond acceptor catalyst on the dimer mechanism in aromatic nucleophilic substitution
url http://hdl.handle.net/20.500.12110/paper_1472779X_v_n4_p479_Palleros
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