Role of hydrogen-bonded nucleophiles in aromatic nucleophilic substitutions in aprotic solvents. Reactions of halonitrobenzenes with ethylenediamine, 3-dimethylamino-1-propylamine and histamine in toluene

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The kinetics of the reactions between 1-halogeno-2,4-dinitrobenzene (halogen = F, C1) and the amines ethylenediamine (EDA) and 3-dimethylamino-1- propylamine (DMPA) were studied in toluene at 25° ±0.2C under pseudo-first-order conditions using varying amounts of amine. Even with C1 as the nucleofugu...

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Autores principales: Alvaro, C.E.S., Nudelman, N.S.
Formato: JOUR
Materias:
Aprotic solvents
Aromatic nucleophilic substitution
Dimer nucleophile mechanism
Hydrogen bond
Hydrogen-bonded nucleophiles
Mixed aggregates
Dimers
Hydrogen bonds
Molecular structure
Solvents
Substitution reactions
Surface treatment
Synthesis (chemical)
Dimer nucleophile mechanisms
Aromatic compounds
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_08943230_v18_n8_p880_Alvaro
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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_08943230_v18_n8_p880_Alvaro2023-10-03T15:41:59Z Role of hydrogen-bonded nucleophiles in aromatic nucleophilic substitutions in aprotic solvents. Reactions of halonitrobenzenes with ethylenediamine, 3-dimethylamino-1-propylamine and histamine in toluene Alvaro, C.E.S. Nudelman, N.S. Aprotic solvents Aromatic nucleophilic substitution Dimer nucleophile mechanism Hydrogen bond Hydrogen-bonded nucleophiles Mixed aggregates Dimers Hydrogen bonds Molecular structure Solvents Substitution reactions Surface treatment Synthesis (chemical) Aprotic solvents Aromatic nucleophilic substitution Dimer nucleophile mechanisms Hydrogen-bonded nucleophiles Mixed aggregates Aromatic compounds The kinetics of the reactions between 1-halogeno-2,4-dinitrobenzene (halogen = F, C1) and the amines ethylenediamine (EDA) and 3-dimethylamino-1- propylamine (DMPA) were studied in toluene at 25° ±0.2C under pseudo-first-order conditions using varying amounts of amine. Even with C1 as the nucleofugue (where usually the first step is rate-determining), a third-order-in-amine kinetic law was observed: these results can be interpreted within the 'dimer nucleophile' mechanism where the amine homo-aggregates are better nucleophiles than the amine monomers. To confirm this interpretation, the reaction of 2,4-dinitrofluorobenzene with histamine was studied in the same solvent. Because of the rigid geometry, an intramolecular hydrogen bond is easily established, which prevents the formation of self-aggregates. Consequently, the plot of kA vs. [histamine] is a straight line, as expected for a classical mechanism of base-catalysed decomposition of the zwitterionic intermediate. All these results are well explained in the frame of the 'dimer nucleophile' mechanism. Copyright © 2005 John Wiley & Sons, Ltd. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_08943230_v18_n8_p880_Alvaro
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Aprotic solvents
Aromatic nucleophilic substitution
Dimer nucleophile mechanism
Hydrogen bond
Hydrogen-bonded nucleophiles
Mixed aggregates
Dimers
Hydrogen bonds
Molecular structure
Solvents
Substitution reactions
Surface treatment
Synthesis (chemical)
Aprotic solvents
Aromatic nucleophilic substitution
Dimer nucleophile mechanisms
Hydrogen-bonded nucleophiles
Mixed aggregates
Aromatic compounds
spellingShingle Aprotic solvents
Aromatic nucleophilic substitution
Dimer nucleophile mechanism
Hydrogen bond
Hydrogen-bonded nucleophiles
Mixed aggregates
Dimers
Hydrogen bonds
Molecular structure
Solvents
Substitution reactions
Surface treatment
Synthesis (chemical)
Aprotic solvents
Aromatic nucleophilic substitution
Dimer nucleophile mechanisms
Hydrogen-bonded nucleophiles
Mixed aggregates
Aromatic compounds
Alvaro, C.E.S.
Nudelman, N.S.
Role of hydrogen-bonded nucleophiles in aromatic nucleophilic substitutions in aprotic solvents. Reactions of halonitrobenzenes with ethylenediamine, 3-dimethylamino-1-propylamine and histamine in toluene
topic_facet Aprotic solvents
Aromatic nucleophilic substitution
Dimer nucleophile mechanism
Hydrogen bond
Hydrogen-bonded nucleophiles
Mixed aggregates
Dimers
Hydrogen bonds
Molecular structure
Solvents
Substitution reactions
Surface treatment
Synthesis (chemical)
Aprotic solvents
Aromatic nucleophilic substitution
Dimer nucleophile mechanisms
Hydrogen-bonded nucleophiles
Mixed aggregates
Aromatic compounds
description The kinetics of the reactions between 1-halogeno-2,4-dinitrobenzene (halogen = F, C1) and the amines ethylenediamine (EDA) and 3-dimethylamino-1- propylamine (DMPA) were studied in toluene at 25° ±0.2C under pseudo-first-order conditions using varying amounts of amine. Even with C1 as the nucleofugue (where usually the first step is rate-determining), a third-order-in-amine kinetic law was observed: these results can be interpreted within the 'dimer nucleophile' mechanism where the amine homo-aggregates are better nucleophiles than the amine monomers. To confirm this interpretation, the reaction of 2,4-dinitrofluorobenzene with histamine was studied in the same solvent. Because of the rigid geometry, an intramolecular hydrogen bond is easily established, which prevents the formation of self-aggregates. Consequently, the plot of kA vs. [histamine] is a straight line, as expected for a classical mechanism of base-catalysed decomposition of the zwitterionic intermediate. All these results are well explained in the frame of the 'dimer nucleophile' mechanism. Copyright © 2005 John Wiley & Sons, Ltd.
format JOUR
author Alvaro, C.E.S.
Nudelman, N.S.
author_facet Alvaro, C.E.S.
Nudelman, N.S.
author_sort Alvaro, C.E.S.
title Role of hydrogen-bonded nucleophiles in aromatic nucleophilic substitutions in aprotic solvents. Reactions of halonitrobenzenes with ethylenediamine, 3-dimethylamino-1-propylamine and histamine in toluene
title_short Role of hydrogen-bonded nucleophiles in aromatic nucleophilic substitutions in aprotic solvents. Reactions of halonitrobenzenes with ethylenediamine, 3-dimethylamino-1-propylamine and histamine in toluene
title_full Role of hydrogen-bonded nucleophiles in aromatic nucleophilic substitutions in aprotic solvents. Reactions of halonitrobenzenes with ethylenediamine, 3-dimethylamino-1-propylamine and histamine in toluene
title_fullStr Role of hydrogen-bonded nucleophiles in aromatic nucleophilic substitutions in aprotic solvents. Reactions of halonitrobenzenes with ethylenediamine, 3-dimethylamino-1-propylamine and histamine in toluene
title_full_unstemmed Role of hydrogen-bonded nucleophiles in aromatic nucleophilic substitutions in aprotic solvents. Reactions of halonitrobenzenes with ethylenediamine, 3-dimethylamino-1-propylamine and histamine in toluene
title_sort role of hydrogen-bonded nucleophiles in aromatic nucleophilic substitutions in aprotic solvents. reactions of halonitrobenzenes with ethylenediamine, 3-dimethylamino-1-propylamine and histamine in toluene
url http://hdl.handle.net/20.500.12110/paper_08943230_v18_n8_p880_Alvaro
work_keys_str_mv AT alvaroces roleofhydrogenbondednucleophilesinaromaticnucleophilicsubstitutionsinaproticsolventsreactionsofhalonitrobenzeneswithethylenediamine3dimethylamino1propylamineandhistamineintoluene
AT nudelmanns roleofhydrogenbondednucleophilesinaromaticnucleophilicsubstitutionsinaproticsolventsreactionsofhalonitrobenzeneswithethylenediamine3dimethylamino1propylamineandhistamineintoluene
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