Journal article

+ 1 other files

Self-assembly of Ag(I) helicates with new enantiopure 5,6-Chiragen type ligands

  • Mamula, Olimpia Institute of Chemical Technology, HES-SO Fribourg, Switzerland - Chemistry Department, University of Fribourg, Switzerland
  • Bark, Thomas Chemistry Department, University of Fribourg, Switzerland
  • Quinodoz, Boris Chemistry Department, University of Fribourg, Switzerland
  • Stoeckli-Evans, Helen Institute of Physics, University of Neuchâtel, Switzerland
  • Zelewsky, Alexander von Chemistry Department, University of Fribourg, Switzerland
Show more…
    24.04.2018
Published in:
  • Inorganica Chimica Acta. - 2018, vol. 475, p. 200–206
English Two new chiral bis-bidentate, C2-symmetrical ligands belonging to the Chiragen family have been synthesised and characterised. They are designed for polynuclear self-assemblies since the two (−)-5,6-pinenebipyridines units are connected by bridges whose length and rigidity avoids the coordination of the bipyridine moieties to the same metal centre. The ligand L1 with a 1,4-dimethylene naphthalene bridge leads, by complexation with Ag(I) cations, to a polymeric, single stranded helix. The helical pitch contains five metal centers, two consecutive metal centers being connected by a bis-bidentate, helically wrapped ligand, one up and the other down resulting in a coordination number four. The chirality (Λ) around each metal centre is controlled by the six asymmetric carbons of the ligands and the homochirality of the metal centers gives rise to a P orientation at the helix level. The 1H-NMR measurements of these species in solution indicate a temperature dependent behaviour pointing out possible equilibria between various [AgnLn]n+ fragments as confirmed by MS-spectroscopy. The ligand L2 with a 4,4′-dimethylene-1,1′-biphenyl bridge reacts with Ag(I) and lead to well resolved and temperature independent 1H- NMR spectra suggesting the formation of a circular helicate.
Faculty
Faculté des sciences et de médecine
Department
Département de Chimie
Language
  • English
Classification
Chemistry
License
License undefined
Identifiers
Persistent URL
https://folia.unifr.ch/unifr/documents/306695
Other files

Statistics

Document views: 10 File downloads:
  • bar_saa.pdf: 3
  • bar_saa_sm.pdf: 2