Journal
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
Volume 2013, Issue 18, Pages 3675-3684Publisher
WILEY-V C H VERLAG GMBH
DOI: 10.1002/ejoc.201300356
Keywords
Nanostructures; Macrocycles; Liquid crystals; Structure elucidation; Click chemistry
Categories
Funding
- University of Strasbourg
- Centre Nationale de la Recherche Scientifique (CNRS)
- Spanish project [CTQ2012-35692]
- FEDER founds
- Swiss National Science Foundation [200020-140298]
- Agence National de la Recherche (ANR)
- Swiss National Science Foundation
Ask authors/readers for more resources
Whereas the reaction of 1,4-bis(2-bromoethyloxy)benzene (4) with paraformaldehyde in the presence of BF3 center dot Et2O afforded exclusively the cyclopentameric pillar[5]arene derivative (5), both cyclopenta- and cyclohexameric macrocycles 5 and 6 were obtained when the reaction of 4 with paraformaldehyde was performed at 45 degrees C in CHCl3 with FeCl3 as the catalyst. Treatment of compounds 4-6 with sodium azide provided the corresponding polyazides, to which a cyanobiphenyl building block was subsequently grafted to generate model compound 1, pillar[5]arene 2, and pillar[6]arene 3, bearing two, ten and twelve mesomorphic subunits, respectively. The liquid-crystalline and thermal properties of the compounds were investigated by polarized optical microscopy (POM), differential scanning calorimetry (DSC), and X-ray diffraction (XRD). Comparison of the liquid-crystalline properties of macrocycles 2 and 3 with those of 1 revealed the strong influence of the macrocyclic pillar[n]arene core on the mesomorphic properties. Whereas only a monotropic mesophase was observed for 1, a broad enantiotropic mesophase was evidenced for both pillar[n]arene derivatives.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available