Aromatic donor-acceptor charge-transfer and metal-ion-complexation-assisted folding of a synthetic polymer

Angewandte Chemie - International Edition

Volumn 43, Issue 25, 2004, Pages 3264-3268

  Ghosh, Suhrit ^a   Ramakrishnan, S ^a  

^a INDIAN INSTITUTE OF SCIENCE   (India)

Author keywords

Charge transfer; Donor acceptor; Polymers; Solvophobic effect; Supramolecular chemistry; Systems

Indexed keywords

COMPLEXATION; MACROMOLECULES; NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; POLYMERS;

SOLVOPHOBIC EFFECT; SYNTHETIC MACROMOLECULES;

CHARGE TRANSFER;

METAL ION; POLYMER;

ARTICLE; COMPLEX FORMATION; ELECTRON TRANSPORT; MACROMOLECULE; PHYSICAL CHEMISTRY; PROTON NUCLEAR MAGNETIC RESONANCE; STRUCTURE ANALYSIS; ULTRAVIOLET SPECTROSCOPY;

ELECTRONS; HYDROCARBONS, AROMATIC; METALS, ALKALI; MOLECULAR STRUCTURE; ORGANOMETALLIC COMPOUNDS; POLYMERS; PROTONS;

EID: 4544365759     PISSN: 14337851     EISSN: None     Source Type: Journal    
DOI: 10.1002/anie.200453860     Document Type: Article

References (42)

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40. 3CN (1:1 v/v). In contrast, there was no change in the chemical shifts in the case of a mixture of the model compounds at the same concentration.
41. The program EQNMR version 2.10 was used to calculate the K values from the variation of the chemical shift of the acceptor proton. (Freeware developed by M. J. Hynes, Chemistry Department, University College, Galway, Ireland). It is evident that the association constant does not directly parallel the extent of change seen in either the charge-transfer absorbance or the chemical shift. It may be reasoned that the extent of change experienced by the donor and acceptor units (both in their NMR and UV/Vis spectra), owing to metal-ion complexation by the loop, would greatly depend on the final geometry of the donor-acceptor complex. Thus, formation of a strong complex with the metal ion need not necessarily bring the donor and acceptor units in the optimum geometry for most effective charge-transfer interaction. Further studies are currently being done on model conor-acceptor oligomers to gain better insight into these aspects.
42. +. A similar variation was reported by Vogtle and co-workers in the case of podands (see reference [11a]). All the spectral variations are included in the Supporting Information.