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H-bond cooperativity: polarisation effects on secondary amides
Formation of a H-bond with an amide carbonyl oxygen atom increases the strength of subsequent H-bonds formed by the amide NH, due to polarisation of the bond. The magnitude of this effect has been quantified by measuring association constants for the formation of 1 : 1 complexes of 2-hydroxylbenzami...
Autores principales: | , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
The Royal Society of Chemistry
2022
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9580511/ https://www.ncbi.nlm.nih.gov/pubmed/36320903 http://dx.doi.org/10.1039/d2sc04271a |
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author | Soloviev, Daniil O. Hanna, Fergal E. Misuraca, Maria Cristina Hunter, Christopher A. |
author_facet | Soloviev, Daniil O. Hanna, Fergal E. Misuraca, Maria Cristina Hunter, Christopher A. |
author_sort | Soloviev, Daniil O. |
collection | PubMed |
description | Formation of a H-bond with an amide carbonyl oxygen atom increases the strength of subsequent H-bonds formed by the amide NH, due to polarisation of the bond. The magnitude of this effect has been quantified by measuring association constants for the formation of 1 : 1 complexes of 2-hydroxylbenzamides with tri-n-butyl phosphine oxide. In 2-hydroxybenzamides, there is an intramolecular H-bond between the phenol OH group and the carbonyl oxygen atom. Comparison of the association constants measured for compounds with and without the 2-hydroxy group allows direct quantification of the effect of the intramolecular H-bond on the H-bond donor properties of the amide NH group. Substituents were used to modulate the strength of the intramolecular and intermolecular H-bonds. The presence of an intramolecular H-bond increases the strength of the intermolecular H-bond by more than one order of magnitude in n-octane solution. The increase in the H-bond donor parameter used to describe the amide NH group is directly proportional to the H-bond donor parameter of the phenol OH group that makes the intramolecular H-bond. These polarisation effects will lead to substantial cooperativity in complex systems that feature networks of non-covalent interactions, and the measurements described here provide a quantitative basis for understanding such phenomena. |
format | Online Article Text |
id | pubmed-9580511 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2022 |
publisher | The Royal Society of Chemistry |
record_format | MEDLINE/PubMed |
spelling | pubmed-95805112022-10-31 H-bond cooperativity: polarisation effects on secondary amides Soloviev, Daniil O. Hanna, Fergal E. Misuraca, Maria Cristina Hunter, Christopher A. Chem Sci Chemistry Formation of a H-bond with an amide carbonyl oxygen atom increases the strength of subsequent H-bonds formed by the amide NH, due to polarisation of the bond. The magnitude of this effect has been quantified by measuring association constants for the formation of 1 : 1 complexes of 2-hydroxylbenzamides with tri-n-butyl phosphine oxide. In 2-hydroxybenzamides, there is an intramolecular H-bond between the phenol OH group and the carbonyl oxygen atom. Comparison of the association constants measured for compounds with and without the 2-hydroxy group allows direct quantification of the effect of the intramolecular H-bond on the H-bond donor properties of the amide NH group. Substituents were used to modulate the strength of the intramolecular and intermolecular H-bonds. The presence of an intramolecular H-bond increases the strength of the intermolecular H-bond by more than one order of magnitude in n-octane solution. The increase in the H-bond donor parameter used to describe the amide NH group is directly proportional to the H-bond donor parameter of the phenol OH group that makes the intramolecular H-bond. These polarisation effects will lead to substantial cooperativity in complex systems that feature networks of non-covalent interactions, and the measurements described here provide a quantitative basis for understanding such phenomena. The Royal Society of Chemistry 2022-10-03 /pmc/articles/PMC9580511/ /pubmed/36320903 http://dx.doi.org/10.1039/d2sc04271a Text en This journal is © The Royal Society of Chemistry https://creativecommons.org/licenses/by/3.0/ |
spellingShingle | Chemistry Soloviev, Daniil O. Hanna, Fergal E. Misuraca, Maria Cristina Hunter, Christopher A. H-bond cooperativity: polarisation effects on secondary amides |
title | H-bond cooperativity: polarisation effects on secondary amides |
title_full | H-bond cooperativity: polarisation effects on secondary amides |
title_fullStr | H-bond cooperativity: polarisation effects on secondary amides |
title_full_unstemmed | H-bond cooperativity: polarisation effects on secondary amides |
title_short | H-bond cooperativity: polarisation effects on secondary amides |
title_sort | h-bond cooperativity: polarisation effects on secondary amides |
topic | Chemistry |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9580511/ https://www.ncbi.nlm.nih.gov/pubmed/36320903 http://dx.doi.org/10.1039/d2sc04271a |
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