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Entropy directs the self-assembly of supramolecular palladium coordination macrocycles and cages

The self-assembly of palladium-based cages is frequently rationalized via the cumulative enthalpy (ΔH) of bonds between coordination nodes (M, i.e., Pd) and ligand (L) components. This focus on enthalpic rationale limits the complete understanding of the Gibbs free energy (ΔG) for self-assembly, as...

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Autores principales: Poole III, D. A., Bobylev, E. O., Mathew, S., Reek, J. N. H.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Royal Society of Chemistry 2022
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9430592/
https://www.ncbi.nlm.nih.gov/pubmed/36128226
http://dx.doi.org/10.1039/d2sc03154j
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author Poole III, D. A.
Bobylev, E. O.
Mathew, S.
Reek, J. N. H.
author_facet Poole III, D. A.
Bobylev, E. O.
Mathew, S.
Reek, J. N. H.
author_sort Poole III, D. A.
collection PubMed
description The self-assembly of palladium-based cages is frequently rationalized via the cumulative enthalpy (ΔH) of bonds between coordination nodes (M, i.e., Pd) and ligand (L) components. This focus on enthalpic rationale limits the complete understanding of the Gibbs free energy (ΔG) for self-assembly, as entropic (ΔS) contributions are overlooked. Here, we present a study of the M(2)(lin)L(3) intermediate species (M = dinitrato(N,N,N′,N′-tetramethylethylenediamine)palladium(ii), (lin)L = 4,4′-bipyridine), formed during the synthesis of triangle-shaped (M(3)(lin)L(3)) and square-shaped (M(4)(lin)L(4)) coordination macrocycles. Thermochemical analyses by variable temperature (VT) (1)H-NMR revealed that the M(2)(lin)L(3) intermediate exhibited an unfavorable (relative) ΔS compared to M(3)(lin)L(3) (triangle, ΔTΔS = +5.22 kcal mol(−1)) or M(4)(lin)L(4) (square, ΔTΔS = +2.37 kcal mol(−1)) macrocycles. Further analysis of these constructs with molecular dynamics (MD) identified that the self-assembly process is driven by ΔG losses facilitated by increases in solvation entropy (ΔS(solv), i.e., depletion of solvent accessible surface area) that drives the self-assembly from “open” intermediates toward “closed” macrocyclic products. Expansion of our computational approach to the analysis of self-assembly in Pd(n)(ben)L(2n) cages ((ben)L = 4,4'-(5-ethoxy-1,3-phenylene)dipyridine), demonstrated that ΔS(solv) contributions drive the self-assembly of both thermodynamic cage products (i.e., Pd(12)(ben)L(24)) and kinetically-trapped intermediates (i.e., Pd(8)(c)L(16)).
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spelling pubmed-94305922022-09-19 Entropy directs the self-assembly of supramolecular palladium coordination macrocycles and cages Poole III, D. A. Bobylev, E. O. Mathew, S. Reek, J. N. H. Chem Sci Chemistry The self-assembly of palladium-based cages is frequently rationalized via the cumulative enthalpy (ΔH) of bonds between coordination nodes (M, i.e., Pd) and ligand (L) components. This focus on enthalpic rationale limits the complete understanding of the Gibbs free energy (ΔG) for self-assembly, as entropic (ΔS) contributions are overlooked. Here, we present a study of the M(2)(lin)L(3) intermediate species (M = dinitrato(N,N,N′,N′-tetramethylethylenediamine)palladium(ii), (lin)L = 4,4′-bipyridine), formed during the synthesis of triangle-shaped (M(3)(lin)L(3)) and square-shaped (M(4)(lin)L(4)) coordination macrocycles. Thermochemical analyses by variable temperature (VT) (1)H-NMR revealed that the M(2)(lin)L(3) intermediate exhibited an unfavorable (relative) ΔS compared to M(3)(lin)L(3) (triangle, ΔTΔS = +5.22 kcal mol(−1)) or M(4)(lin)L(4) (square, ΔTΔS = +2.37 kcal mol(−1)) macrocycles. Further analysis of these constructs with molecular dynamics (MD) identified that the self-assembly process is driven by ΔG losses facilitated by increases in solvation entropy (ΔS(solv), i.e., depletion of solvent accessible surface area) that drives the self-assembly from “open” intermediates toward “closed” macrocyclic products. Expansion of our computational approach to the analysis of self-assembly in Pd(n)(ben)L(2n) cages ((ben)L = 4,4'-(5-ethoxy-1,3-phenylene)dipyridine), demonstrated that ΔS(solv) contributions drive the self-assembly of both thermodynamic cage products (i.e., Pd(12)(ben)L(24)) and kinetically-trapped intermediates (i.e., Pd(8)(c)L(16)). The Royal Society of Chemistry 2022-08-10 /pmc/articles/PMC9430592/ /pubmed/36128226 http://dx.doi.org/10.1039/d2sc03154j Text en This journal is © The Royal Society of Chemistry https://creativecommons.org/licenses/by/3.0/
spellingShingle Chemistry
Poole III, D. A.
Bobylev, E. O.
Mathew, S.
Reek, J. N. H.
Entropy directs the self-assembly of supramolecular palladium coordination macrocycles and cages
title Entropy directs the self-assembly of supramolecular palladium coordination macrocycles and cages
title_full Entropy directs the self-assembly of supramolecular palladium coordination macrocycles and cages
title_fullStr Entropy directs the self-assembly of supramolecular palladium coordination macrocycles and cages
title_full_unstemmed Entropy directs the self-assembly of supramolecular palladium coordination macrocycles and cages
title_short Entropy directs the self-assembly of supramolecular palladium coordination macrocycles and cages
title_sort entropy directs the self-assembly of supramolecular palladium coordination macrocycles and cages
topic Chemistry
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9430592/
https://www.ncbi.nlm.nih.gov/pubmed/36128226
http://dx.doi.org/10.1039/d2sc03154j
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