Hélène Nierengarten

Fullerodendrimers with peripheral triethyleneglycol chains: synthesis, mass spectrometric characterization, and photophysical properties

Poly(aryl ether) dendritic branches terminated with peripheral triethyleneglycol chains have been attached to C60. The resulting fullerodendrimers have been characterised by electrospray mass spectrometry (ESMS), which appears to be a particularly interesting analytical tool for the unambiguous structural assignment of such high molecular weight fullerene derivatives. Their photophysical properties have been systematically investigated in three solvents, namely toluene, dichloromethane, and acetonitrile. The changes observed in the photophysical properties along the series suggest an increasing interaction between the poly(aryl ether) dendritic wedges and the fullerene core, which brings about an increasing isolation of the central chromophore from the exterior. Finally, thanks to their high solubility, fullerodendrimers 1–4 have been easily incorporated in mesoporous silica glasses and preliminary measurements on the resulting doped samples have revealed efficient optical limiting properties.

Chiral recognition properties of spiroacetal polyethers using electrospray ionisation mass spectrometry

Associations between monocyclic or bicyclic polyethers (1 – 10) incorporating a chiral spiroacetal moiety and ammonium enantiomeric pairs of phenylglycine methyl ester (G1) or phenyl glycinol (G2) were studied by Electrospray Ionisation Mass Spectrometry by the enantiomer-labelled method. Several spiro-crowns and spiro-cryptands showed chiral recognition properties.

A supramolecular oligophenylenevinylene–C60 conjugate

Abstract A new methanofullerene derivative with an ammonium subunit has been prepared and its ability to form a supramolecular complex with an oligophenylenevinylene (OPV)–crown ether conjugate evidenced by NMR, electrospray mass spectrometry and luminescence experiments.

High Molecular Weight CuII Coordination Polymers and Their Characterisation by Electrospray Mass Spectrometry (ESMS)

The ligands L and ligand L* self-assemble with CuII in different solvents to give a mixture of coordination polymers. These artificial nanostructures have been characterised with the help of ESMS, the only analytical tool that allows their unambiguous characterisation. Kinetic and thermodynamic ESMS studies have excluded the possibility that these compounds form aggregates during the ES process.

p-tert-Butylcalix[4]arene Functionalised with Bipyridyl Carboxylates for Lanthanide Complexation: Synthesis, Photophysical Properties, Solution and Solid State Behavior

A new ligand based on a p-tert-butylcalix[4]arene functionalised with three 6-carboxylato-2,2′-bipyridine arms reacted with lanthanide(III) cations to form 2:2 complexes in the solid state, whereas in solution, a concentration-dependent equilibrium is observed between 2:2 and 1:1 species, as evidenced by ES-MS and metal luminescence measurements. In the X-ray molecular structure of the terbium complex two branched calixarene platforms share one pendant arm in order to provide a neutral dimeric structure which is held together by a strong hydrogen bonded network together with efficient π–π stacking of two pyridine rings belonging to each ligand.

Alkali cation induced liquid crystalline properties of an oligophenylenevinylene-benzocrown ether conjugate

An oligophenylenevinylene-benzocrown ether conjugate has been prepared and its binding selectivity for alkali metal ions evaluated by electrospray mass spectrometry. Whereas this benzocrown-ether derivative does not exhibit any liquid crystalline properties, the self-assembly by coordination to potassium or cesium leads to supramolecular sandwich complexes with mesomorphic properties.