title: Redox control of molecular motions in bipyridinium appended calixarenes.
abstract: A series of redox-responsive architectures featuring two bipyridinium units introduced onto the lower rim of a calixarene skeleton has been synthesized. The redox-triggered intramolecular dimerization of the reduced bipyridiniums has been investigated by electrochemistry, spectroelectrochemistry and by theoretical chemistry. The spectroscopic signature of the intramolecular dimers was found to evolve significantly with the size of the alkyl linker introduced between the calixarene skeleton and the bipyridinium units. On account of experimental data supported by theoretical calculations, these differences have been attributed to the extent of the orbital overlap in the π-dimerized species, involving either four or only two of the pyridine rings of the bipyridinium radical cations stacked in eclipsed or staggered conformations, respectively.
authors.affiliation: Département de Chimie Moléculaire (UMR5250), Laboratoire de Chimie Inorganique Rédox, Université Joseph Fourier/CNRS, Grenoble, France.
authors.forename: Adriana
authors.initials: A
authors.lastname: Iordache
authors.forename: Ramu
authors.initials: R
authors.lastname: Kannappan
authors.forename: Estelle
authors.initials: E
authors.lastname: Métay
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Duclos
authors.forename: Stéphane
authors.initials: S
authors.lastname: Pellet-Rostaing
authors.forename: Marc
authors.initials: M
authors.lastname: Lemaire
authors.forename: Anne
authors.initials: A
authors.lastname: Milet
authors.forename: Eric
authors.initials: E
authors.lastname: Saint-Aman
authors.forename: Christophe
authors.initials: C
authors.lastname: Bucher