| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 5279165 | Tetrahedron Letters | 2007 | 6 Pages |
The linear and polycatenar type 1H-imidazole amphiphiles showing a strong self-assembly tendency to build various supramolecular structures in bulk were synthesized by the esterification reaction of 4â²-alkyloxy phenols (for 1-4) and hydroxyphenyl trialkyloxybenzoates (for 5-7) with 4-chlorocarbonyl imidazole. The linear 1H-imidazole amphiphiles formed thermotropic smectic phases, but compound 4 with an ethyl group instead of hydrogen on 1N did not show a mesophase. The polycatenar type 1H-imidazole amphiphiles (5-7) formed thermotropic hexagonal columnar and cubic phases. A phase transition was observed from a columnar phase to a cubic phase as the temperature increased on heating, and vice versa on cooling. In the POM study for compounds 5-7, optically isotropic phases first appeared on cooling from the isotropic melts, and then birefringent mesophases with a nonspecific texture appeared on further cooling. The X-ray analysis shows that the optically isotropic phases were very likely micellar cubic phases with Pm3n symmetry. The birefringent phases were confirmed as hexagonal columnar phases.
Graphical abstractPolycatenar 1H-imidazole amphiphiles formed highly ordered thermotropic liquid crystals and showed phase transitions from a columnar phase to a cubic phase as the temperature increased on heating, and vice versa on cooling.Download full-size image
