File Download

There are no files associated with this item.

  Links for fulltext
     (May Require Subscription)
Supplementary

Article: Molecular meccano, 49. - Pseudorotaxanes and catenanes containing a redox-active unit derived from tetrathiafulvalene

TitleMolecular meccano, 49. - Pseudorotaxanes and catenanes containing a redox-active unit derived from tetrathiafulvalene
Authors
KeywordsCatenanes
Molecular machines
Pseudorotaxanes
Template-directed synthesis
Tetrathiafulvalenes
Issue Date1999
Citation
European Journal of Organic Chemistry, 1999, n. 5, p. 985-994 How to Cite?
AbstractTwo bis(2-oxy-1,3-propylenedithio)tetrathiafulvalene-containing acyclic polyethers and two macrocyclic polyethers, each incorporating one bis(2-oxy- 1,3-propylenedithio)tetrathiafulvalene unit and one p-phenylene ring, have been synthesized. The two acyclic polyethers are bound by cyclobis(paraquat- p-phenylene) with pseudorotaxane geometries in solution. The two macrocyclic polyethers have been mechanically interlocked with this tetracationic cyclophane to form [2]catenanes in a kinetically controlled self-assembly process. The X-ray crystallographic analysis of one of the two [2]catenanes and 1H-NMR-spectroscopic studies of both compounds showed that the p- phenylene ring of the macrocyclic polyether is located inside the cavity of the tetracationic cyclophane, while the bis(2-oxy-1,3- propylenedithio)tetrathiafulvalene unit resides alongside. The [2]pseudorotaxanes and [2]catenanes show broad bands around 780 nm, arising from the charge-transfer (CT) interaction between the electron-donor tetrathiafulvalene-(TTF-)type unit and the electron-acceptor units of the tetracationic cyclophane. 1H-NMR-spectroscopic studies have shown that the [2]pseudorotaxanes dissociate into their separate components upon oxidation of the TTF-type unit, as a result of disruption of the CT interaction and electrostatic repulsion between the tetracationic host and the newly formed monocationic guest. The subsequent reduction of the guest to its neutral state affords back the pseudorotaxane-type complex restoring the original equilibrium. The results obtained from electrochemical experiments are consistent with the reversible, redox-driven dethreading/rethreading process observed by 1H-NMR spectroscopy. Variable-temperature 1H-NMR-spectroscopic investigations have revealed two dynamic processes, both involving the relative movements of the mechanically interlocked components in the [2]catenanes. The two consecutive oxidation processes involving the TTF-type unit, observed electrochemically, are displaced toward more positive potentials compared with the free cyclic polyethers. The two reversible two- electron reduction processes, characteristic of free cyclobis(paraquat-p- phenylene), separate into four reversible one-electron processes because of the topological difference between the 'inside' and 'alongside' electron- acceptor units in the [2]catenane.
Persistent Identifierhttp://hdl.handle.net/10722/332446
ISSN
2023 Impact Factor: 2.5
2023 SCImago Journal Rankings: 0.584
ISI Accession Number ID

 

DC FieldValueLanguage
dc.contributor.authorAsakawa, Masumi-
dc.contributor.authorAshton, Peter R.-
dc.contributor.authorBalzani, Vincenzo-
dc.contributor.authorBoyd, Sue E.-
dc.contributor.authorCredi, Alberto-
dc.contributor.authorMattersteig, Gunter-
dc.contributor.authorMenzer, Stephan-
dc.contributor.authorMontalti, Marco-
dc.contributor.authorRaymo, Françisco M.-
dc.contributor.authorRuffilli, Cristina-
dc.contributor.authorStoddart, J. Fraser-
dc.contributor.authorVenturi, Margherita-
dc.contributor.authorWilliams, David J.-
dc.date.accessioned2023-10-06T05:11:33Z-
dc.date.available2023-10-06T05:11:33Z-
dc.date.issued1999-
dc.identifier.citationEuropean Journal of Organic Chemistry, 1999, n. 5, p. 985-994-
dc.identifier.issn1434-193X-
dc.identifier.urihttp://hdl.handle.net/10722/332446-
dc.description.abstractTwo bis(2-oxy-1,3-propylenedithio)tetrathiafulvalene-containing acyclic polyethers and two macrocyclic polyethers, each incorporating one bis(2-oxy- 1,3-propylenedithio)tetrathiafulvalene unit and one p-phenylene ring, have been synthesized. The two acyclic polyethers are bound by cyclobis(paraquat- p-phenylene) with pseudorotaxane geometries in solution. The two macrocyclic polyethers have been mechanically interlocked with this tetracationic cyclophane to form [2]catenanes in a kinetically controlled self-assembly process. The X-ray crystallographic analysis of one of the two [2]catenanes and 1H-NMR-spectroscopic studies of both compounds showed that the p- phenylene ring of the macrocyclic polyether is located inside the cavity of the tetracationic cyclophane, while the bis(2-oxy-1,3- propylenedithio)tetrathiafulvalene unit resides alongside. The [2]pseudorotaxanes and [2]catenanes show broad bands around 780 nm, arising from the charge-transfer (CT) interaction between the electron-donor tetrathiafulvalene-(TTF-)type unit and the electron-acceptor units of the tetracationic cyclophane. 1H-NMR-spectroscopic studies have shown that the [2]pseudorotaxanes dissociate into their separate components upon oxidation of the TTF-type unit, as a result of disruption of the CT interaction and electrostatic repulsion between the tetracationic host and the newly formed monocationic guest. The subsequent reduction of the guest to its neutral state affords back the pseudorotaxane-type complex restoring the original equilibrium. The results obtained from electrochemical experiments are consistent with the reversible, redox-driven dethreading/rethreading process observed by 1H-NMR spectroscopy. Variable-temperature 1H-NMR-spectroscopic investigations have revealed two dynamic processes, both involving the relative movements of the mechanically interlocked components in the [2]catenanes. The two consecutive oxidation processes involving the TTF-type unit, observed electrochemically, are displaced toward more positive potentials compared with the free cyclic polyethers. The two reversible two- electron reduction processes, characteristic of free cyclobis(paraquat-p- phenylene), separate into four reversible one-electron processes because of the topological difference between the 'inside' and 'alongside' electron- acceptor units in the [2]catenane.-
dc.languageeng-
dc.relation.ispartofEuropean Journal of Organic Chemistry-
dc.subjectCatenanes-
dc.subjectMolecular machines-
dc.subjectPseudorotaxanes-
dc.subjectTemplate-directed synthesis-
dc.subjectTetrathiafulvalenes-
dc.titleMolecular meccano, 49. - Pseudorotaxanes and catenanes containing a redox-active unit derived from tetrathiafulvalene-
dc.typeArticle-
dc.description.naturelink_to_subscribed_fulltext-
dc.identifier.doi10.1002/(sici)1099-0690(199905)1999:5<985::aid-ejoc985>3.0.co;2-o-
dc.identifier.scopuseid_2-s2.0-0032770935-
dc.identifier.issue5-
dc.identifier.spage985-
dc.identifier.epage994-
dc.identifier.isiWOS:000080228100006-

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats