Tetrathiafulvalene radical cation dimerization in a bistable tripodal [4]rotaxane

Ivan Aprahamian, John Carl Olsen, Ali Trabolsi, J. Fraser Stoddart

Research output: Contribution to journalArticle

Abstract

The template-directed synthesis of a bistable tripodal [4]rotaxane, which has cyclobis(paraquat-p-phenylene) (CBPQT4+) as the π-electron-de-ficient rings, and tetrathiafulvalene (TTF) and 1,5-dioxynaphthalene units as the pairs of π-electron-rich recognition sites located on all three legs of the tripodal dumbbell, is described. The chemical and electrochemical oxidation of the [4]rotaxane and its tripo dal dumbbell have allowed us to unravel an unprecedented TTF+ radical cation dimerization. In fact, two types of TTF dimers, namely, the radical cation dimer [TTF+]2 and the mixed-valence one [(TTF) 2]+, have been ob served at room temperature for the tripodal dumbbell, whereas, in the case of the [4]rotaxane, only the radical cation dimer [TTF+]2 is formed. This anomaly can be explained if it is accepted that most of the neutral TTF units in the [4]rotaxane are encircled by CBPQT4+ rings, which renders the formation of the mixed-valence dimer [(TTF)2]+ highly unfavorable.

Original languageEnglish (US)
Pages (from-to)3889-3895
Number of pages7
JournalChemistry - A European Journal
Volume14
Issue number13
DOIs
StatePublished - Apr 28 2008

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Rotaxanes
Dimerization
Dimers
Cations
Positive ions
Electrons
Electrochemical oxidation
Paraquat
tetrathiafulvalene

Keywords

  • Bistability
  • Click chemistry
  • Dimerization
  • Rotaxanes
  • Template synthesis

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Tetrathiafulvalene radical cation dimerization in a bistable tripodal [4]rotaxane. / Aprahamian, Ivan; Olsen, John Carl; Trabolsi, Ali; Stoddart, J. Fraser.

In: Chemistry - A European Journal, Vol. 14, No. 13, 28.04.2008, p. 3889-3895.

Research output: Contribution to journalArticle

Aprahamian, Ivan ; Olsen, John Carl ; Trabolsi, Ali ; Stoddart, J. Fraser. / Tetrathiafulvalene radical cation dimerization in a bistable tripodal [4]rotaxane. In: Chemistry - A European Journal. 2008 ; Vol. 14, No. 13. pp. 3889-3895.
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