Photoinduced Electron Transfer and Intramolecular Folding in a Tricarbonylrhenium (Bi)pyridine Based Donor/Crown/Acceptor Assembly: Dependence on Solvent

Christine A. Berg-Brennan, Dong I. Yoon, Robert V. Slone, Amy P. Kazala, Joseph T Hupp

Research output: Contribution to journalArticle

31 Citations (Scopus)

Abstract

The title assembly diplays an emissive rhenium-to-pyridine charge-transfer state that is partially quenched by electron transfer to an attached acceptor (nitrobenzene). Quenching is preceded by intramolecular folding (J. Am. Chem. Soc. 1993, 115, 2048). Variable-temperature quenching measurements can be used to determine the characteristic temperature, Ttr, above which unfolded photoexcited state conformations become favored over folded conformations. Similar information for the ground state can be obtained from variable-temperature NMR measurements. Studies in eight solvents show that excited state folding is (1) enthalpically favored but entropically disfavored (all solvents), (2) correlated (via Ttr) with the inverse dielectric strength of the solvent, and (3) enhanced in comparison to folding in the electronic ground state (studies in one solvent). The combined evidence points to a folding reaction that is driven by optimization of localized Coulombic interactions. Optimization of solvent cohesive interactions, however, may possibly also play a role in the folding reaction.

Original languageEnglish
Pages (from-to)2032-2035
Number of pages4
JournalInorganic Chemistry
Volume35
Issue number7
Publication statusPublished - 1996

Fingerprint

folding
pyridines
electron transfer
assembly
Electrons
Ground state
Conformations
Quenching
quenching
Rhenium
optimization
ground state
nitrobenzenes
rhenium
Excited states
Temperature
temperature
Charge transfer
charge transfer
Nuclear magnetic resonance

ASJC Scopus subject areas

  • Inorganic Chemistry

Cite this

Photoinduced Electron Transfer and Intramolecular Folding in a Tricarbonylrhenium (Bi)pyridine Based Donor/Crown/Acceptor Assembly : Dependence on Solvent. / Berg-Brennan, Christine A.; Yoon, Dong I.; Slone, Robert V.; Kazala, Amy P.; Hupp, Joseph T.

In: Inorganic Chemistry, Vol. 35, No. 7, 1996, p. 2032-2035.

Research output: Contribution to journalArticle

Berg-Brennan, Christine A. ; Yoon, Dong I. ; Slone, Robert V. ; Kazala, Amy P. ; Hupp, Joseph T. / Photoinduced Electron Transfer and Intramolecular Folding in a Tricarbonylrhenium (Bi)pyridine Based Donor/Crown/Acceptor Assembly : Dependence on Solvent. In: Inorganic Chemistry. 1996 ; Vol. 35, No. 7. pp. 2032-2035.
@article{d150a0a82df4465b9e91d7c566d3afd0,
title = "Photoinduced Electron Transfer and Intramolecular Folding in a Tricarbonylrhenium (Bi)pyridine Based Donor/Crown/Acceptor Assembly: Dependence on Solvent",
abstract = "The title assembly diplays an emissive rhenium-to-pyridine charge-transfer state that is partially quenched by electron transfer to an attached acceptor (nitrobenzene). Quenching is preceded by intramolecular folding (J. Am. Chem. Soc. 1993, 115, 2048). Variable-temperature quenching measurements can be used to determine the characteristic temperature, Ttr, above which unfolded photoexcited state conformations become favored over folded conformations. Similar information for the ground state can be obtained from variable-temperature NMR measurements. Studies in eight solvents show that excited state folding is (1) enthalpically favored but entropically disfavored (all solvents), (2) correlated (via Ttr) with the inverse dielectric strength of the solvent, and (3) enhanced in comparison to folding in the electronic ground state (studies in one solvent). The combined evidence points to a folding reaction that is driven by optimization of localized Coulombic interactions. Optimization of solvent cohesive interactions, however, may possibly also play a role in the folding reaction.",
author = "Berg-Brennan, {Christine A.} and Yoon, {Dong I.} and Slone, {Robert V.} and Kazala, {Amy P.} and Hupp, {Joseph T}",
year = "1996",
language = "English",
volume = "35",
pages = "2032--2035",
journal = "Inorganic Chemistry",
issn = "0020-1669",
publisher = "American Chemical Society",
number = "7",

}

TY - JOUR

T1 - Photoinduced Electron Transfer and Intramolecular Folding in a Tricarbonylrhenium (Bi)pyridine Based Donor/Crown/Acceptor Assembly

T2 - Dependence on Solvent

AU - Berg-Brennan, Christine A.

AU - Yoon, Dong I.

AU - Slone, Robert V.

AU - Kazala, Amy P.

AU - Hupp, Joseph T

PY - 1996

Y1 - 1996

N2 - The title assembly diplays an emissive rhenium-to-pyridine charge-transfer state that is partially quenched by electron transfer to an attached acceptor (nitrobenzene). Quenching is preceded by intramolecular folding (J. Am. Chem. Soc. 1993, 115, 2048). Variable-temperature quenching measurements can be used to determine the characteristic temperature, Ttr, above which unfolded photoexcited state conformations become favored over folded conformations. Similar information for the ground state can be obtained from variable-temperature NMR measurements. Studies in eight solvents show that excited state folding is (1) enthalpically favored but entropically disfavored (all solvents), (2) correlated (via Ttr) with the inverse dielectric strength of the solvent, and (3) enhanced in comparison to folding in the electronic ground state (studies in one solvent). The combined evidence points to a folding reaction that is driven by optimization of localized Coulombic interactions. Optimization of solvent cohesive interactions, however, may possibly also play a role in the folding reaction.

AB - The title assembly diplays an emissive rhenium-to-pyridine charge-transfer state that is partially quenched by electron transfer to an attached acceptor (nitrobenzene). Quenching is preceded by intramolecular folding (J. Am. Chem. Soc. 1993, 115, 2048). Variable-temperature quenching measurements can be used to determine the characteristic temperature, Ttr, above which unfolded photoexcited state conformations become favored over folded conformations. Similar information for the ground state can be obtained from variable-temperature NMR measurements. Studies in eight solvents show that excited state folding is (1) enthalpically favored but entropically disfavored (all solvents), (2) correlated (via Ttr) with the inverse dielectric strength of the solvent, and (3) enhanced in comparison to folding in the electronic ground state (studies in one solvent). The combined evidence points to a folding reaction that is driven by optimization of localized Coulombic interactions. Optimization of solvent cohesive interactions, however, may possibly also play a role in the folding reaction.

UR - http://www.scopus.com/inward/record.url?scp=0000640122&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0000640122&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0000640122

VL - 35

SP - 2032

EP - 2035

JO - Inorganic Chemistry

JF - Inorganic Chemistry

SN - 0020-1669

IS - 7

ER -