Université de Fribourg

Laterally stretched polycyclic aromatic hydrocarbons: synthesis of dibenzophenanthroheptaphene and tetrabenzotriphenylenopyranthrene derivatives

Alameddine, Bassam ; Anju, Rajamohanan Sobhana ; Shetty, Suchetha ; Baig, Noorullah ; Al-Sagheer, Fakhreia ; Al-Mousawi, Saleh ; Jenny, Titus A.

In: New Journal of Chemistry, 2017, vol. 41, no. 13, p. 6025–6032

Efficient methods for the synthesis of dibenzophenanthroheptaphene (DBPH) and tetrabenzotriphenylenopyranthrene (TBTP) were developed. As a result, a series of unprecedented derivatives of DBPH (1a–c) and TBTP (2a–b) were conventionally obtained from the Scholl cyclodehydrogenation reaction of their respective tribenzopentaphene synthons. An alternative convergent synthesis of DBPH is also...

Université de Fribourg

Tribenzopentaphene derivatives with lateral aromatic groups: the effect of the nature and position of substituents on emission properties

Alameddine, Bassam ; Anju, Rajamohanan Sobhana ; Al-Sagheer, Fakhreia ; Jenny, Titus A.

In: New Journal of Chemistry, 2016, vol. 40, no. 12, p. 10363–10370

Nine new derivatives of the trapezoidal tribenzopentaphene (TBP) polycyclic aromatic hydrocarbon (PAH) were synthesized via the Suzuki–Miyaura palladium catalyzed cross-coupling reaction. The novel TBP derivatives, which bear various rigid and flexible aromatic groups either at their more accessible (R1) or congested (R2) bases, were fully characterized using high resolution mass...

Université de Fribourg

Influence of linear and branched perfluoroalkylated side chains on the π–π stacking behaviour of hexa-peri-hexabenzocoronene and thermotropic properties

Alameddine, Bassam ; Aebischer, Olivier Frédéric ; Heinrich, Benoît ; Guillon, Daniel ; Donnio, Bertrand ; Jenny, Titus A.

In: Supramolecular Chemistry, 2014, vol. 26, no. 2, p. 125–137

The thermotropic properties and self-assembly of two different series of hexa-peri-hexabenzocoronenes (HBC) bearing either linear or branched perfluoroalkylated side chains, each with a wide range of alkyl spacer and perfluorinated tail lengths, have been studied. Correlations between thermogravimetric analysis, differential scanning calorimetry, polarised optical microscopy and small-angle X-ray...

Université de Fribourg

Synthesis of novel alkyl- and perfluoroalkyl-substituted polycondensed aromatic hydrocarbons for molecular electronics

Schindler, Mauro K. ; Jenny, Titus (Dir.)

Thèse de doctorat : Université de Fribourg, 2010.

The demand for electronic devices has exploded in the last few years. They are all around us and we use them everyday; TV, mobile phones, computers, etc. Most people could not imagine living without them. The presence of these devices has increased the consumption of electrical power and other resources such as silicon and petrol derivatives. This increase has itself created a demand for...

Université de Fribourg

Synthesis of alkyl-Substituted tribenzopentaphenes as versatile polycondensed aromatic hydrocarbon π-π stacking building blocks

Alameddine, Bassam ; Caba, Sofia Martin ; Schindler, Mauro ; Jenny, Titus A.

In: Synthesis, 2012, vol. 44, p. 1928-1934

We show the versatile synthesis of four tribenzopentaphene derivatives bearing alkyl side chains at three different positions. Substitutions on two of these positions led to subtle intensity changes at the lines of the blue emission, whereas alkylation in the bay region led to dimerization of the pentaphene derivative, resulting in a distortion of the chromophore geometry and an emission shift to...

Université de Fribourg

New polycondensed aromatic compoundsfor applications in the hydrogen cycle

Fragnière, Nicolas ; Jenny, Titus (Dir.)

Thèse de doctorat : Université de Fribourg, 2011.

This work presents the synthesis of a new perfluorinated sulfonic acid function HBC which car¬ries a sulfonic acid at the end of one perfluorinated side-chain.The aim of the introduction of this sulfonic acid is its ability to form proton channels which could be used as electrolyte in pro¬ton exchange membranes for fuel cells. The channels would be created by the formation of stacks of three...

Université de Fribourg

Synthesis of Hexa-peri-hexobenzocoronenes Carrying Linear or Branched Perfluoroalkylated Side Chains

Aebischer, Olivier F. ; Muñoz, David T. ; Tondo, Patrick ; Débieux, Jean-Luc ; Jenny, Titus A.

In: Synthesis, 2010, vol. 7, p. 1123-1140

Substituted disc-shaped perfluoroalkylated hexa-peri-hexabenzocoronenes (HBC), known to self-assemble into conducting ordered architectures, were synthesized and characterized. A systematic variation of the linear or branched perfluoroalkylated side chains was performed in order to screen the influence of the lateral chain on their one-dimensional self-aggregation.

Université de Fribourg

Controlling the supramolecular assembly of perfluorinated polycondensed aromatic hydrocarbons by side chain engineering

Aebischer, Olivier F. ; Jenny, Titus (Dir.) ; Weiss, Antoine (Codir.)

Thèse de doctorat : Université de Fribourg, 2007 ; Nr. 1575.

The possibilities of industry to process and to engineer materials at the nanometer level rapidly increase and products using materials engineered at the nanometer level emerge on the markets. In the long term, it is hardly possible to estimate, from the present point, where the ability to engineer materials on the nano-scale will lead human beings, whether the dream of a molecular nanotechnology...

Université de Fribourg

Synthesis and investigation of new large self-assembled supramolecules as potential electron emitters

Alameddine, Bassam ; Jenny, Titus (Dir.)

Thèse de doctorat : Université de Fribourg, 2004 ; no 1440.

Nanotechnology, a research area that covers many scientific disciplines such as Medicine, Biology, Physics and Chemistry has found a great interest in research institutions and wide applications in industries. This is due to many reasons; from these we note the control down to the molecular level providing thereby a greatest efficiency and an important added value as a reason of the low cost of...

Université de Fribourg

Controlling the lateral aggregation of perfluoroalkylated hexa-peri-hexabenzocoronenes

Aebischer, Olivier F. ; Aebischer, Annina ; Donnio, Bertrand ; Alameddine, Bassam ; Dadras, Massoud ; Güdel, Hans-Ulrich ; Guillon, Daniel ; Jenny, Titus A.

In: Journal of Materials Chemistry, 2007, vol. 17, no. 13, p. 1262-1267

The investigation of two hexa-peri-hexabenzocoronene (HBC) derivatives carrying linear or branched perfluoroalkylated side chains is reported. Polycondensed aromatic hydrocarbons (PAH) such as HBC derivatives are well known to self-organize to form highly ordered monomolecular stacks, which in turn show a concentration- and solvent-dependent lateral aggregation. However, possible...