2312-15-4Relevant articles and documents
Synthesis and liquid crystalline properties of new triazine-based π-conjugated macromolecules with chiral side groups
Akkurt, Nihat,Al-Jumaili, Mohammed Hadi Ali,C?kar, Fatih,Ocak, Hale,Torun, Lokman
, p. 726 - 735 (2020)
In this study, we reported the synthesis of a new tribranched macromolecule liquid crystal with triazine in the centre. The central triazine core is bonded via sequences of Sonigashira coupling to 3 triazine unites through acetylenic bridges. The triazines at the periphery are substituted with 2 chiral citronellyloxy side groups. The salt of the resulting star-shaped macromolecule, which was oily at room temperature, with 4-dodecyloxybenzoic acid at 1:1 ratio exhibited a Smectic C (SmC) mesophase. The liquid crystalline properties of organic salt were investigated using DSC (differential scanning calorimetry) and POM (polarizing optical microscopy).
Ionic interaction of tri-armed structure based on benzene ring: synthesis and characterization
Al-Jumaili, Mohammed Hadi Ali,Akkurt, Nihat,Torun, Lokman
, p. 551 - 558 (2021)
Abstract: Liquid crystalline is a state of matter which combines the properties of liquid and a crystalline solid. Ionic liquid crystals are a new class of materials which exhibit phase transition at low temperature. A new structure was synthesized based on a benzene ring carrying three armed, two arms of triazine ring and the third arm is phenoxy benzene. The presence of alkyl chain groups on the periphery reduced the mesophase transitions which are desirable for low-temperature applications of liquid crystals. The substitution was achieved efficiently by Sonogashira coupling. The tri-armed compound was synthesized successfully through cross-coupling. However, it was oily and no transition phase was observed. Therefore, to increase the liquid crystal possibility, the compound was mixed with 4-(dodecyloxy)benzoic acid (4-DBA) with 1:1 ratio to produce an organic salt through hydrogen bonding. The organic salt obtained by ionic interaction between the tri-armed compound and 4-DBA exhibited a phase transition at low temperature. However, ionic liquid crystals are important class of mesomorphic materials and have considered as sealants due to their very low vapour pressure which demonstrated a proficient electrolyte systems for their anisotropic phase such as high ionic conductivity and diffusion along with excellent thermal stability. All the intermediate compounds and final compounds were confirmed by spectroscopic techniques (1H NMR, 13C NMR, FT-IR, and HRMS). Graphic abstract: [Figure not available: see fulltext.].
Synthesis and mesomorphic characterization of some novel steroidal mesogens: A structure–property correlation
Bhat S, Vanishree,Kumar, Sandeep,Raghunathan, V. A.
, (2021/08/25)
The steroidal derivatives are found to be extremely good mesogens since their inception. Because of their inherent chirality, they have the potential to induce a wide variety of liquid crystalline phases, including frustrated phases depending upon the structure of the steroidal skeleton and the substituents attached. In this report, a series of novel monoalkoxy and dialkoxy benzoate derivatives of ergosterol and a few monoalkoxy derivatives of stigmasterol have been synthesized and their mesomorphic property has been investigated. The derivatives exhibited various mesophases including SmA, SmC*, N*, TGB and blue phases. Also, the gelation ability of some of these derivatives with various organic solvents has been examined. Furthermore, the mesomorphism of these derivatives has been compared with the analogous cholesteryl counterparts.
New macromolecular structures based on benzene core, synthesis and characterization
Ali, Mohammed Hadi,Torun, Lokman
, p. 465 - 472 (2021/09/28)
A series of new compounds based on benzene ring as a central core substituted with aromatic compounds such as (benzene and pyridine) and three armed of 2-chloro-4,6-bis((3,7-dimethyloct-6-en-1-yl) oxy)-1,3,5-triazine, have been obtained by sequential nucleophilic substitution of chlorine atoms in cyanuric chloride. The substitution at the acetylenic periphery on the central benzene ring has been achieved efficiently by Sonogashira coupling. Equimolar mixtures of the six-armed compounds based on the benzene core with the complementary 4-dodecyloxybenzoic acid, which already possessed liquid crystal property, has resulted in an organic salt. The obtained organic salts have been investigated by polarizing optical microscopy (POM) and differential scanning calorimetry (DSC). The synthesized compounds have been confirmed by spectroscopic methods (1H and13C NMR and mass spectromery).
