Polar Uç Gruplara Sahip Yeni Üç-Halkalı Kalkon-İmin Türevlerinin Sentezi, Yapısal ve Mesomorfik Karakterizasyonu

Öz

Bu çalışmada, uç pozisyonlardan birinde n-dodesiloksi grubu, diğerinde ise siyano veya brom grubu bulunan üç-benzen-halkalı merkezi üniteden oluşan yeni kalkon-imin türevleri sentezlenmiştir. Elde edilen türevlerin kimyasal yapıları spektral analizlerle (1H-, 13C/APT-NMR ve FT-IR) aydınlatılmıştır. Türevlerin mesomorfik davranışları diferansiyel taramalı kalorimetri (DSC) ve polarize optik mikroskop (POM) ile gözlemlenmiştir. Siyano-uçlu kalkon-imin türevinin (3a) 19 ˚C termal sıcaklık aralığı ile karakterize edilen enansiyotropik SmA mesofazını ve ayrıca M mesofazını sergilerken, brom-uçlu kalkon-imin türevinin (3b) ise herhangi bir mesomorfik davranış göstermediği belirlenmiştir. Bu sonuç, polar uç grubunun türü ve doğasının moleküllerin sıvı kristal özelliklerini büyük ölçüde etkilediğini vurgulamaktadır.

Anahtar Kelimeler

• Sıvı kristaller
• Kalkon-imin türevleri
• Mesomorfik davranış
• Çubuksu molekül

Synthesis, Structural and Mesomorphic Characterization of New Three-Ring Chalcone-Imine Derivatives with Polar End Groups

Öz

In this study, new chalcone-imine derivatives composed of three-benzene-ring central unit containing n-dodecyloxy group at one end and cyano or bromo group at other end have been synthesized. Chemical structures of the obtained derivatives have been clarified by spectral analyses (1H-, 13C/APT-NMR and FT-IR). The mesomorphic behaviour and optical textures of the derivatives have been observed by differential scanning calorimetry (DSC) and polarized optical microscopy (POM). It was determined that cyano-terminated chalcone-imine derivative (3a) exhibits enantiotropic SmA mesophase, characterized by thermal range of 19 ˚C and also a M mesophase, while bromo-terminated chalcone-imine derivative (3b) does not show any mesomorphic behaviour. This result emphasizes that the type and the nature of the polar end group has a huge impact on the liquid crystalline properties of the molecules.

Anahtar Kelimeler

• Liquid crystals
• Chalcone-imine derivatives
• Mesomorphic behaviour
• Rod-like molecule

Kaynakça

1. [1] Andrienko, D. 2018. Introduction to liquid crystals. Journal of Molecular Liquids, 267, 520–541.
2. [2] Kato, T., Mizoshita, N., Kishimoto, K. 2006. Functional Liquid‐Crystalline Assemblies: Self‐Organized Soft Materials. Angewandte Chemie International Edition, 45(1), 38–68.
3. [3] Kato, T. 2002. Self-Assembly of Phase-Segregated Liquid Crystal Structures. Science, 295, 2414–2418.
4. [4] Gurboga, B., Tuncgovde, E.B., Kemiklioglu, E. 2022. Liquid crystal‐based elastomers in tissue engineering. Biotechnology and Bioengineering, 119(4), 1047–1052.
5. [5] Leu, J.S.L., Teoh, J.J.X., Ling, A.L.Q., Chong, J., Loo, Y.S., Mat Azmi, I.D., Zahid, N.I., Bose, R.J.C., Madheswaran, T. 2023. Recent Advances in the Development of Liquid Crystalline Nanoparticles as Drug Delivery Systems. Pharmaceutics, 15(5), 1421.
6. [6] Wang, Z., Xu, T. Noel, A., Chen, Y.-C., Liu, T. 2021. Applications of liquid crystals in biosensing. Soft Matter, 17(18), 4675–4702.
7. [7] Fu, C., Li, D., Liu, C., Zhang, Y., Zhang, J., Cheng, Y. 2025. Chiral Co‐Assembled Liquid Crystal Polymer Network Enabled by In‐Situ Photopolymerization for High‐Performance CP‐OLEDs. Angewandte Chemie, 137(36).
8. [8] Denisov, I.G., Grinkova, Y. V., Lazarides, A.A., Sligar, S.G. 2004. Directed Self-Assembly of Monodisperse Phospholipid Bilayer Nanodiscs with Controlled Size. Journal of the American Chemical Society, 126(11), 3477–3487.

9. [9] Matharu, A.S., Jeeva, S., Ramanujam, P.S. 2007. Liquid crystals for holographic optical data storage. Chemical Society Reviews, 36(12), 1868.
10. [10] Ahmed, H.A., Mansour, E., Hagar, M. 2020. Mesomorphic study and DFT simulation of calamitic Schiff base liquid crystals with electronically different terminal groups and their binary mixtures. Liquid Crystals, 47(14-15), 2292–2304.
11. [11] Veerabhadraswamy, B.N., Rao, D.S.S., Prasad, S.K., Yelamaggad, C. V. 2015. Optically active, three-ring calamitic liquid crystals: the occurrence of frustrated, helical and polar fluid mesophases. New Journal of Chemistry, 39(3), 2011–2027.
12. [12] Zaki, A.A., Hagar, M., Alnoman, R.B., Jaremko, M., Emwas, A.-H., Ahmed, H.A. 2020. Mesomorphic, Optical and DFT Aspects of Near to Room-Temperature Calamitic Liquid Crystal. Crystals, 10(11), 1044.
13. [13] Foo, K.-L., Ha, S.-T., Yeap, G.-Y. 2022. Synthesis and phase transition behavior of calamitic liquid crystals containing heterocyclic core and lateral ethoxy substituent. Phase Transitions, 95(2), 178–192.
14. [14] Trân, H.Q., Kawano, S., Thielemann, R.E., Tanaka, K., Ravoo, B.J. 2024. Calamitic Liquid Crystals for Reversible Light‐Modulated Phase Regulation Based on Arylazopyrazole Photoswitches. Chemistry – A European Journal, 30(2).
15. [15] Rothera, J.G., Yu, J., AlNajm, K., Butrus, R., Ahangari‐Bashash, E., Watanabe, L.K., Rawson, J.M., Dmitrienko, A., Vukotic, V.N., Eichhorn, S.H. 2025. Core‐Only Calamitic Liquid Crystals: Molecular Design and Optoelectronic Properties. Chemistry – An Asian Journal, 20(8).
16. [16] Al-Zahrani, S.A., Khan, M.T., Jevtovic’, V., Masood, N., Jeilani, Y.A., Ahmed, H.A. 2023. Design of Liquid Crystal Materials Based on Palmitate, Oleate, and Linoleate Derivatives for Optoelectronic Applications. Molecules, 28(4) 1744.
17. [17] Bisoyi, H.K., Li, Q. 2022. Liquid Crystals: Versatile Self-Organized Smart Soft Materials. Chemical Reviews, 122(5), 4887–4926.
18. [18] Bubnov, A., Cigl, M., Mironov, S., Otruba, M., Penkov, D., Pacherová, O., Bohmová, Z., Hamplová, V. 2023. The correlations between the molecular core structure and mesomorphic behaviour for chiral liquid crystals with several (S)-lactate groups. Journal of Molecular Liquids, 387, 122590.
19. [19] Al-Mutabagani, L.A., Alshabanah, L.A., Gomha, S.M., Abolibda, T.Z., Shaban, M., Ahmed, H.A. 2021. Synthesis and Mesomorphic and Electrical Investigations of New Furan Liquid Crystal Derivatives. Frontiers in Chemistry, 9.
20. [20] Han, Z.-Y., Kun, S.-Q., Kang, J.-T., Jia, Y.-G. 2022. New (-)-menthol-based blue phase liquid crystals with different polar substituents in the terminal group: Synthesis, mesophase behaviors, and DFT calculations. Journal of Molecular Structure, 1263, 133147.
21. [21] Ali, M.H., Saad, G.R., Ahmed, N.H.S., Fahmi, A.A. 2023. Synthesis and physico-chemical properties of dilateral flouro azo/ester four aromatic ring mesogens and their mixtures of liquid crystals. Liquid crystals, 50(5), 737–753.
22. [22] Srinivasa, H.T. 2022. Polar cyano/nitrile group-derived rod-shaped nematic liquid crystals: synthesis and characterizations†. Molecular Crystals and Liquid Crystals, 737(1), 11–22.
23. [23] Wu, R., Xiong, G., Chen, Y., Wang, S. 2024. Control Patterning of Cyanobiphenyl Liquid Crystals for Electricity Applications. Langmuir, 40(41), 21693–21700.
24. [24] Kress, K.C., Kaller, M., Axenov, K. V., Tussetschläger, S., Laschat, S. 2012. Synthesis and mesomorphic properties of calamitic malonates and cyanoacetates tethered to 4-cyanobiphenyls. Beilstein Journal of Organic Chemistry, 8, 371–378.
25. [25] Paterson, D.A., Abberley, J.P., Harrison, W.T., Storey, J.M., Imrie, C.T. 2017. Cyanobiphenyl-based liquid crystal dimers and the twist-bend nematic phase. Liquid Crystals, 1–20.
26. [26] Pathak, G., Phettong, B., Chattham, N. 2025. Optimization of 4-Cyano-4’-pentylbiphenyl Liquid Crystal Dispersed with Photopolymer: Application Towards Smart Windows and Aerospace Technology. Polymers, 17(16), 2232.
27. [27] Alaasar, M., Tschierske, C. 2019. Nematic phases driven by hydrogen-bonding in liquid crystalline nonsymmetric dimers. Liquid crystals, 46(1), 124–130.
28. [28] Hagar, M., Ahmed, H.A., Alnoman, R.B., Jaremko, M., Emwas, A.-H., Sioud, S., Abu Al-Ola, K.A. 2021. New Liquid Crystal Assemblies Based on Cyano-Hydrogen Bonding Interactions. Frontiers in Chemistry, 9.
29. [29] Sezgin, B., Can Karanlık, C., Karanlık, G. 2025. Exploring the mesophase and optical behavior of novel furan-based chalcone liquid crystals with ester/azo linkages. New Journal of Chemistry, 49(29), 12676–12687.
30. [30] Wan, D., Liang, L., Mo, L., Che, Z., Hu, M., Li, J., Li, J. 2025. Synthesis and properties of high birefringence vinylene-bridged fluorinated terphenyl liquid crystals. Journal of Molecular Structure, 1345, 141668.
31. [31] Pytlarczyk, M., Kula, P. 2019. Synthesis and mesomorphic properties of 4,4”-dialkynyl-2’,3’-difluoro-p-terphenyls – the influence of C≡C acetylene linking bridge. Liquid Crystals, 46(4), 618–628.
32. [32] Habeeb, H.Q.A., Tomi, I.H.R. 2025. A new series of asymmetric calamitic esters based on 1,3,4-thiadiazole: synthesis, characterisation, and study of their thermo-optic properties. Liquid Crystals, 1–12.
33. [33] Patil N, V., Sahoo, R., Veerabhadraswamy, B.N., Chakraborty, S., Dhar, R., Mathad, R.D., Yelamaggad, C. V. 2021. Polarization of three- ring Schiff base ferroelectric liquid crystals. Liquid Crystals, 48(8), 1194–1205.
34. [34] Shirodkar, M.J., Bhat, K.S., Bhattacharjee, D., Sonali, M.K., Mahesha, M.G., Bhagavath, P. 2025. Mesomorphic and DFT study of new difluoro substituted Schiff base liquid crystals. Scientific Reports, 15(1), (2025) 15540.
35. [35] Panchal, J.C., Chaudhary, M.Y., Patel, H.N., Patel, T.M., Thakur, S., Mittal, S., Vyas, K.M., Sangani, C.B., Ahmed, S. 2025. Synthesis of new liquid crystal Schiff’s bases bearing ester moiety, DFT calculation and mesomorphic studies. Journal of Molecular Structure, 1321, 140078.
36. [36] Fadhil, M.Z.A.M., Mustamin, M.A., Jamain, Z. 2024. Liquid crystalline behaviour of symmetrical thermotropic Schiff base compounds. Journal of Molecular Structure, 1315, 138929.
37. [37] Ahmed, H.A., Aboelnaga, A. 2022. Synthesis and mesomorphic study of new phenylthiophene liquid crystals. Liquid Crystals, 49(6), 804–811.
38. [38] Zhu, X., Yin, F., Zhao, H., Chen, S., Bian, Z. 2017. Some new azobenzene liquid crystals involving chalcone and ester linkages. RSC Adv., 7(73), 46344–46353.
39. [39] Palahally Thimmappa, S. Sangarashettihalli Krishnegowda, G., Sudhir, A., Hemavathi Nagaraju, D. 2025. Chalcone based liquid crystalline compounds beyond biological applications: a review. Liquid Crystals, 52(5-6), 453–477.
40. [40] Katariya, K.D., Nakum, K.J., Hagar, M. 2022. New thiophene chalcones with ester and Schiff base mesogenic Cores: Synthesis, mesomorphic behaviour and DFT investigation. Journal of Molecular Liquids, 359, 119296.
41. [41] Katariya, K.D., Nakum, K.J., Soni, H., Nada, S., Hagar, M. 2023. Imine based Four-Ring Chalcone-Ester liquid Crystals: Synthesis, Characterization, mesomorphic behaviour and DFT approach. Journal of Molecular Liquids, 380, 121719.
42. [42] Bashir, N., Hameed, S., Muhammad, K., Vieira, A.A., Bechtold, I.H., Hameed, S. 2023. 4-(Aroyloxybenzoyloxy)benzonitriles with pronounced homeotropic SmA alignment. Liquid Crystals, 50(11-12), 1806–1813.
43. [43] Tanaka, S., Takezawa, Y., Kanie, K., Muramatsu, A. 2023. Forming a Homeotropic SmA Structure of Liquid Crystalline Epoxy Resin on an Amine-Modified Surface. ACS Omega, 8(36), 32365–32371.