Inter- and intramolecular hydrogen bonds in polyamines: Variable-concentration 1H-NMR studies

Inter- and intramolecular hydrogen bonding play an important role in determining the arrangement, physical properties, and reactivity of a great diversity of structures in chemical and biological systems. Several aromatic nucleophilic substitutions (ANS) in nonpolar aprotic, (non-HBD), solvents rece...

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Autores principales: Nudelman, N.S., Alvaro, C.E.S.
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Acceso en línea:http://hdl.handle.net/20.500.12110/paper_08943230_v24_n11_p1067_Nudelman
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spelling todo:paper_08943230_v24_n11_p1067_Nudelman2023-10-03T15:42:04Z Inter- and intramolecular hydrogen bonds in polyamines: Variable-concentration 1H-NMR studies Nudelman, N.S. Alvaro, C.E.S. 1H-NMR studies on amine solutions ANS in non-HBD solvents dimer nucleophile mechanism dimerization equilibrium constants hydrogen-bonded nucleophiles hydrogen-bonding effects on 1H-NMR Amine solutions ANS in non-HBD solvents dimer nucleophile mechanism Hydrogen-bonded nucleophiles Hydrogen-bonding effects Amines Association reactions Dimerization Dimers Equilibrium constants Hydrogen Nucleophiles Hydrogen bonds Inter- and intramolecular hydrogen bonding play an important role in determining the arrangement, physical properties, and reactivity of a great diversity of structures in chemical and biological systems. Several aromatic nucleophilic substitutions (ANS) in nonpolar aprotic, (non-HBD), solvents recently studied in our laboratory have demonstrated the importance of self-association of amines by hydrogen-bond interactions. In this paper, we describe 1H-NMR studies carried out at room temperature on bi- and polyfunctionalized amines, namely: N-(3-amino-1-propyl)morpholine (3-APMo), histamine, 2-guanidinobenzimidazole (2-GB), 1,2-diaminoethane (EDA), 3-dimethylamino-l-propylamine (DMPA), and 1-(2-aminoethyl)piperidine (2-AEPip). By 1H-NMR measurements of amine solutions at variable concentrations we have shown that 3-APMo, histamine and 2-GB are able to form a six-membered ring by intramolecular hydrogen bonding, while EDA, DMPA, and 2-AEPip form dimers by intermolecular hydrogen bonds. Likewise, variable concentration 1H-NMR studies allowed estimation of the corresponding equilibrium constants for the dimerization. These results are correlated with experimental kinetic results of ANS, confirming hereto the relevance of the "dimer mechanism" in reactions involving these amines. Copyright © 2011 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_v24_n11_p1067_Nudelman
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic 1H-NMR studies on amine solutions
ANS in non-HBD solvents
dimer nucleophile mechanism
dimerization equilibrium constants
hydrogen-bonded nucleophiles
hydrogen-bonding effects on 1H-NMR
Amine solutions
ANS in non-HBD solvents
dimer nucleophile mechanism
Hydrogen-bonded nucleophiles
Hydrogen-bonding effects
Amines
Association reactions
Dimerization
Dimers
Equilibrium constants
Hydrogen
Nucleophiles
Hydrogen bonds
spellingShingle 1H-NMR studies on amine solutions
ANS in non-HBD solvents
dimer nucleophile mechanism
dimerization equilibrium constants
hydrogen-bonded nucleophiles
hydrogen-bonding effects on 1H-NMR
Amine solutions
ANS in non-HBD solvents
dimer nucleophile mechanism
Hydrogen-bonded nucleophiles
Hydrogen-bonding effects
Amines
Association reactions
Dimerization
Dimers
Equilibrium constants
Hydrogen
Nucleophiles
Hydrogen bonds
Nudelman, N.S.
Alvaro, C.E.S.
Inter- and intramolecular hydrogen bonds in polyamines: Variable-concentration 1H-NMR studies
topic_facet 1H-NMR studies on amine solutions
ANS in non-HBD solvents
dimer nucleophile mechanism
dimerization equilibrium constants
hydrogen-bonded nucleophiles
hydrogen-bonding effects on 1H-NMR
Amine solutions
ANS in non-HBD solvents
dimer nucleophile mechanism
Hydrogen-bonded nucleophiles
Hydrogen-bonding effects
Amines
Association reactions
Dimerization
Dimers
Equilibrium constants
Hydrogen
Nucleophiles
Hydrogen bonds
description Inter- and intramolecular hydrogen bonding play an important role in determining the arrangement, physical properties, and reactivity of a great diversity of structures in chemical and biological systems. Several aromatic nucleophilic substitutions (ANS) in nonpolar aprotic, (non-HBD), solvents recently studied in our laboratory have demonstrated the importance of self-association of amines by hydrogen-bond interactions. In this paper, we describe 1H-NMR studies carried out at room temperature on bi- and polyfunctionalized amines, namely: N-(3-amino-1-propyl)morpholine (3-APMo), histamine, 2-guanidinobenzimidazole (2-GB), 1,2-diaminoethane (EDA), 3-dimethylamino-l-propylamine (DMPA), and 1-(2-aminoethyl)piperidine (2-AEPip). By 1H-NMR measurements of amine solutions at variable concentrations we have shown that 3-APMo, histamine and 2-GB are able to form a six-membered ring by intramolecular hydrogen bonding, while EDA, DMPA, and 2-AEPip form dimers by intermolecular hydrogen bonds. Likewise, variable concentration 1H-NMR studies allowed estimation of the corresponding equilibrium constants for the dimerization. These results are correlated with experimental kinetic results of ANS, confirming hereto the relevance of the "dimer mechanism" in reactions involving these amines. Copyright © 2011 John Wiley & Sons, Ltd.
format JOUR
author Nudelman, N.S.
Alvaro, C.E.S.
author_facet Nudelman, N.S.
Alvaro, C.E.S.
author_sort Nudelman, N.S.
title Inter- and intramolecular hydrogen bonds in polyamines: Variable-concentration 1H-NMR studies
title_short Inter- and intramolecular hydrogen bonds in polyamines: Variable-concentration 1H-NMR studies
title_full Inter- and intramolecular hydrogen bonds in polyamines: Variable-concentration 1H-NMR studies
title_fullStr Inter- and intramolecular hydrogen bonds in polyamines: Variable-concentration 1H-NMR studies
title_full_unstemmed Inter- and intramolecular hydrogen bonds in polyamines: Variable-concentration 1H-NMR studies
title_sort inter- and intramolecular hydrogen bonds in polyamines: variable-concentration 1h-nmr studies
url http://hdl.handle.net/20.500.12110/paper_08943230_v24_n11_p1067_Nudelman
work_keys_str_mv AT nudelmanns interandintramolecularhydrogenbondsinpolyaminesvariableconcentration1hnmrstudies
AT alvaroces interandintramolecularhydrogenbondsinpolyaminesvariableconcentration1hnmrstudies
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