Conformational dynamics of α,β,γ,δ-tetraarylporphyrins and their dications

Jennie Wang Dirks, George Underwood, Jolene Cox Matheson, John Devens Gust

Research output: Contribution to journalArticle

50 Citations (Scopus)

Abstract

Rotational isomerism in several tetraarylporphyrin free bases and the corresponding dications has been studied by using dynamic 1H NMR spectroscopy. The average free energy of activation for rotation of a single aryl ring for the stereoisomers of α,β,γ,δ-tetrakis(2-methoxyphenyl)porphyrin is ΔG433 = 25.9 kcal/mol. The barrier for the corresponding dication is ΔG388 = 23.0 kcal/mol. For α,β,γ,δ-tetrakis(2,4-dimethoxyphenyl)porphyrin and its dication, the rotational barriers are ΔG433 = 25.2 and ΔG388 = 21.8 kcal/mol, respectively. These results shed light on the questions of the degree of distortion of the porphyrin macrocycle in solution and the orientation of the aryl rings relative to the mean porphyrin plane.

Original languageEnglish
Pages (from-to)2551-2555
Number of pages5
JournalJournal of Organic Chemistry
Volume44
Issue number14
Publication statusPublished - 1979

Fingerprint

Porphyrins
Stereoisomerism
Nuclear magnetic resonance spectroscopy
Free energy
Chemical activation

ASJC Scopus subject areas

  • Organic Chemistry

Cite this

Conformational dynamics of α,β,γ,δ-tetraarylporphyrins and their dications. / Dirks, Jennie Wang; Underwood, George; Matheson, Jolene Cox; Gust, John Devens.

In: Journal of Organic Chemistry, Vol. 44, No. 14, 1979, p. 2551-2555.

Research output: Contribution to journalArticle

Dirks, JW, Underwood, G, Matheson, JC & Gust, JD 1979, 'Conformational dynamics of α,β,γ,δ-tetraarylporphyrins and their dications', Journal of Organic Chemistry, vol. 44, no. 14, pp. 2551-2555.
Dirks, Jennie Wang ; Underwood, George ; Matheson, Jolene Cox ; Gust, John Devens. / Conformational dynamics of α,β,γ,δ-tetraarylporphyrins and their dications. In: Journal of Organic Chemistry. 1979 ; Vol. 44, No. 14. pp. 2551-2555.
@article{ba4d7653141f4360ac495d8ad2cc0de5,
title = "Conformational dynamics of α,β,γ,δ-tetraarylporphyrins and their dications",
abstract = "Rotational isomerism in several tetraarylporphyrin free bases and the corresponding dications has been studied by using dynamic 1H NMR spectroscopy. The average free energy of activation for rotation of a single aryl ring for the stereoisomers of α,β,γ,δ-tetrakis(2-methoxyphenyl)porphyrin is ΔG≠433 = 25.9 kcal/mol. The barrier for the corresponding dication is ΔG≠388 = 23.0 kcal/mol. For α,β,γ,δ-tetrakis(2,4-dimethoxyphenyl)porphyrin and its dication, the rotational barriers are ΔG≠433 = 25.2 and ΔG≠388 = 21.8 kcal/mol, respectively. These results shed light on the questions of the degree of distortion of the porphyrin macrocycle in solution and the orientation of the aryl rings relative to the mean porphyrin plane.",
author = "Dirks, {Jennie Wang} and George Underwood and Matheson, {Jolene Cox} and Gust, {John Devens}",
year = "1979",
language = "English",
volume = "44",
pages = "2551--2555",
journal = "Journal of Organic Chemistry",
issn = "0022-3263",
publisher = "American Chemical Society",
number = "14",

}

TY - JOUR

T1 - Conformational dynamics of α,β,γ,δ-tetraarylporphyrins and their dications

AU - Dirks, Jennie Wang

AU - Underwood, George

AU - Matheson, Jolene Cox

AU - Gust, John Devens

PY - 1979

Y1 - 1979

N2 - Rotational isomerism in several tetraarylporphyrin free bases and the corresponding dications has been studied by using dynamic 1H NMR spectroscopy. The average free energy of activation for rotation of a single aryl ring for the stereoisomers of α,β,γ,δ-tetrakis(2-methoxyphenyl)porphyrin is ΔG≠433 = 25.9 kcal/mol. The barrier for the corresponding dication is ΔG≠388 = 23.0 kcal/mol. For α,β,γ,δ-tetrakis(2,4-dimethoxyphenyl)porphyrin and its dication, the rotational barriers are ΔG≠433 = 25.2 and ΔG≠388 = 21.8 kcal/mol, respectively. These results shed light on the questions of the degree of distortion of the porphyrin macrocycle in solution and the orientation of the aryl rings relative to the mean porphyrin plane.

AB - Rotational isomerism in several tetraarylporphyrin free bases and the corresponding dications has been studied by using dynamic 1H NMR spectroscopy. The average free energy of activation for rotation of a single aryl ring for the stereoisomers of α,β,γ,δ-tetrakis(2-methoxyphenyl)porphyrin is ΔG≠433 = 25.9 kcal/mol. The barrier for the corresponding dication is ΔG≠388 = 23.0 kcal/mol. For α,β,γ,δ-tetrakis(2,4-dimethoxyphenyl)porphyrin and its dication, the rotational barriers are ΔG≠433 = 25.2 and ΔG≠388 = 21.8 kcal/mol, respectively. These results shed light on the questions of the degree of distortion of the porphyrin macrocycle in solution and the orientation of the aryl rings relative to the mean porphyrin plane.

UR - http://www.scopus.com/inward/record.url?scp=0008326004&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0008326004&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0008326004

VL - 44

SP - 2551

EP - 2555

JO - Journal of Organic Chemistry

JF - Journal of Organic Chemistry

SN - 0022-3263

IS - 14

ER -