CC BY
4
478 CHEMICAL PROBLEMS 2024 no. 4 (22) ISSN 2221-8688
UDC 548.3
SYNTHESIS, CHARACTERIZATION, AND STUDY OF THE CRYSTALLINE PROPERTIES OF ASTERISM COMPOUNDS
Dardaa A. Ibrahim, Hanaa K. Salih
Department of Chemistry, College of Science, Tikrit University, Tikrit, Iraq
email: dardaa@,tu. edu. iq
Received 15.05.2024 Accepted 04.07.2024
Abstract: This study involves the synthesis of asterism compounds (D1-D6) through the reaction of 1 mole of benzene 1,3,5-triol with 3 moles ofprepared pentacyclic ring ester derivatives, dissolved in absolute ethanol. The validity of the compound structures was (confirmed using physical and spectroscopic methods such as infrared spectroscopy, and proton nuclear magnetic resonance spectroscopy. Additionally, melting points and purity were determined, and reaction progress was monitored by Thin-Layer Chromatography (TLC). The liquid crystal phases of certain prepared compounds were examined using a polarizing optical microscope (POM).
Keywords: Asterism compounds, Esters, Liquid crystals. DOI: 10.32737/2221-8688-2024-4-478-488
1. Introduction
Liquid crystals represent a transitional state between the irregular liquid state and the ordered crystalline solid state [1, 2]. Liquid crystals were described as the fourth state of matter and were called fluid crystals or floating crystals [3]. Liquid crystals exhibit a state intermediate between the solid phase, where molecular motion is constrained and molecular organization is complete in terms of position and direction [4], and the isotropic or liquid phase [5, 6], where molecular motion is free and this phase exhibits random organization, despite displaying properties attributable to both liquid and solid states, they possess unique properties not present in either liquid or solid states [7]. Liquid crystals are a type of fluid containing a specific system in which molecules are arranged [8]. This arrangement makes the substance anisotropic, meaning its physical properties are not present in all directions [9]. Classification of different phases of thermotropic liquid Crystals Nematic-thread like molecules, parallel arrangement and Discotic -disk like molecules and Smectic-soap like smectic A molecules with
transitional/ rotational motion and smectic C molecules arrangement in layers parallel tonormal and Chiral-also known as cholesteric [10].
The most distinguishing feature of these molecules is their possession of flat shapes resembling sheets or elongated shapes resembling rods, and with the assistance of these shapes, the molecules arrange themselves parallel to each other [11, 12]. Liquid crystals have numerous applications in medicine and industry, including common applications such as their use in watches, computers, television screens, and electronic games [13, 14].
This study tries to synthesize asterism compounds (D1-D6) via a meticulous organic reaction. The significance of this process lies in the strategic choice of benzene 1,3,5-triol as the central core due to its symmetrical structure and reactivity, which facilitates optimal interaction with the pentacyclic ester moieties. Dissolving the reactants in absolute ethanol ensures a high-purity solvent environment that minimizes potential side reactions and maximizes product
CHEMICAL PROBLEMS 2024 no. 4 (22)
www.chemprob.org
yield. This methodological approach not only underscores the precision required in forming complex organic compounds but also highlights ethanol role as an efficient solvent in promoting effective esterification reactions. The resulting asterism compounds may exhibit unique chemical properties and potential applications across various fields such as pharmaceuticals,
materials science, and supramolecular chemistry. By carefully controlling reaction conditions and leveraging the inherent reactivity of benzene triol and pentacyclic esters, this study will advances our ability to design and synthesize novel compound architectures with tailored functionalities.
2. Experimental part
2.1. Material and Devices used.
The chemical materials are collected from Fluka, Aldrich, and BDH and used without further purification. The melting points were measured using Electrothermal Melting Apparatus 9300. Bruker FT-IR 8400S spectrophotometer with a scale of (400-4000) cm-1 by KBr disc. 1H-NMR spectra on Bruker instruments running at 400 MHZ. Thin Layer Chromatography (TLC) was performed using Fluka silica gel plates with 0.2 mm thickness, activated with fluorescent silica gel G, and visualization was achieved using UV light.
2.2. Synthesis of Asterism Compounds (discotic) (D1-D6)
In a 50 mL round-bottom flask containing
20 mL of absolute ethanol, 0.001 mol (0.5 g) of benzene 1,3,5-triol is dissolved to this 0.003 mol of prepared thiazolidinone ring esters derivatives dissolved in absolute ethanol is added. After the addition is complete, the reaction mixture is refluxed for 7 hours. The progress of the reactions was monitored using thin-layer chromatography (TLC) and iodine staining. Upon completion of the reflux period, the mixture was cooled and stirred for an additional hour. Precipitate formation was noticed, collected, dried, and recrystallized using ethanol [18, 19]. Table (1) show some physical properties of the synthesized compounds.
Table 1. Yield ratios and some physical properties of compounds (D1-D6)
Comp. Molecular Formula X Yields % Rf M.P. OC Colour
D1 C54H39N3O9S3 H 82 0.58 205-208 Yellow
D2 C54H36Cl3N3O9S3 Cl 70 0.54 188-190 Orange
D3 C54H36Br3N3O9S3 Br 68 0.54 118-120 Orange
D4 C54H36N6O15S3 NO2 67 0.54 199-202 Orange
D5 C57H45N3O12S3 OCH3 59 0.64 173-175 Orange
D6 C57H45N3O9S3 CH3 72 0.61 194-196 Orange
X represent replacement functional group (Figure Compounds (D1-D6) are newly synthesized for the firs M.P. indicates melting points 0 t time
2.3. Study of Liquid Crystal Phases
The liquid crystal phases of certain prepared compounds were examined using a polarizing optical microscope (POM) carried with an electric heater. The microscope was also carried with a high-resolution camera and a heat-resistant lens to obtain high-precision images. The compound under examination,
whose liquid crystal phases were to be investigated, was placed in the liquid crystal phase measurement device, and the compound was heated to its melting point. Subsequently, the compound was cooled, and this process was repeated several times to obtain liquid crystals with clearer geometric shapes [20, 21].
3. Results and Discussion
Asterism Compounds (discotic) (D1-D6) benzene to produce thiazolidinone (Fig. 1). react by 3 moles at 1,3,5-triyl with 1 mole
Fig. 1. The structural formula of the prepared compounds (D1-D6). Reactant (discotic, left side of the equation), productant (thiazolidinone, right side of the equation).
3.1. Properties of Compounds (D1-D6) by FT-IR
The infrared spectrum of compounds (D1-D6) noted that an absorption band appeared in the range (3010-3065) cm-1, which belongs to the stretching of the aromatic (CH) bond. Also, an absorption band appeared in the range (1681-
1696) cm-1 due to the stretching of the carbonyl (C=O) ester bond and an absorption band appeared in the range (1520-1600, 1412-1459) cm-1 due to the stretching of the (C=C) ring bond, and an absorption band appeared in the range (659-696) cm-1 is due to the stretching of the (C-S) bond, [22, 23] (Table 2).
Table 2. FT-IR absorption results for oxazepine derivatives (D1-D6) (cm-1)
Comp. -X vC-H Arom. vC=O ester v C =C vC-S Others
ring
D1 H 3021 1684 1520 1413 696
D2 Cl 3065 1686 1561 1412 674 C-Cl 782
D3 Br 3030 1696 1550 1459 681 C-Br 654
D4 NO2 3025 1684 1573 1454 668 NO2 1538, 1293
D5 OCH3 3048 1686 1600 1444 659 C-H alip. 2993
D6 CH3 3010 1681 1593 1425 694 C-H alip.2953
3.2. Characterization of compounds (D1-D6) by 1H-NMR
The solvent (DMSO-d6) was used for *H-NMR study of all six compounds (D1-D6).
When studying the 1H-NMR spectrum of the compound [D1], it was observed that a multiple signal in the range (7.45-9.06) ppm is attributed to the protons of the aromatic rings, a single signal appears at the chemical shift (6.57) ppm due to the proton of three groups (CH) in
the thiazolidinone ring, and a single signal appears at the chemical shift (4.17) ppm due to the protons of tree groups (CH2) in the thiazolidinone ring, and the appearance of a single signal upon chemical shift (3.34) ppm is attributed to the protons of water (HDO), and a signal appears at the chemical shift (2.48-2.50) ppm is attributed to the protons of the solvent (DMSO-d6) [24,25] (Fig. 2).
Fig. 2. ^-NMR spectrum of the compound (D1 to D5).
The 1H-NMR study of the compound [D2] aromatic rings, a single signal appears at the shows that a multiple signal in the range (7.16- chemical shift (6.37) ppm due to the proton of 8.83) ppm is attributed to the protons of the three groups (CH) in the thiazolidinone ring,
and a single signal appears at the chemical shift (4.14) ppm due to the protons of tree groups (CH2) in the thiazolidinone ring, and the appearance of a single signal upon chemical displacement (3.35) ppm is attributed to the protons of water (HDO), and a signal appears at the chemical shift (2.48-2.51) ppm is attributed to the protons of the solvent (DMSO-d6), [26,27] (Fig. 2).
The 1H-NMR spectrum of the compound [D3] shows that multiple signals in the range (7.24-8.76) ppm is attributed to the protons of the aromatic rings, a single signal appears at the chemical shift (6.42) ppm due to the proton of three groups (CH) in the thiazolidine ring, and a single signal appears at the chemical shift (4.07) ppm due to the protons of tree groups (CH2) in the thiazolidine ring, and the appearance of a single signal upon chemical displacement (3.36) ppm is attributed to the protons of water (HDO), and a signal appears at the chemical shift (2.482.53) ppm is attributed to the protons of the solvent (DMSO-d6) [28, 29] (Fig. 2).
The 1H-NMR spectrum of the compound [D4] reveals that multiple signals in the range (7.46-9.05) ppm is attributed to the protons of the aromatic rings, a single signal appears at the chemical shift (6.57) ppm due to the proton of three groups (CH) in the thiazolidine ring, and a single signal appears at the chemical shift (4.05) ppm due to the protons of tree groups (CH2) in the thiazolidine ring, and the appearance of a single signal upon chemical displacement (3.34) ppm is attributed to the protons of water (HDO), and a signal appears at the chemical shift (2.492.52) parts per million is attributed to the protons of the solvent (DMSO-d6) [30, 31] (Fig. 2).
When studying the 1H-NMR spectrum of the compound [D5], it was observed that a multiple signal in the range (6.82-9.38) ppm is attributed to the protons of the aromatic rings, a single signal appears at the chemical shift (6.51) ppm due to the proton of three groups (CH) in the thiazolidinone ring, and a single signal appears at the chemical shift (4.03) ppm due to the protons of tree groups (CH2) in the thiazolidinone ring, and a single signal appears at the chemical shift (3.92) ppm due to the proton of tree groups (CH3), and the appearance of a single signal upon chemical displacement
(3.33) ppm is attributed to the protons of water (HDO), and a signal appears at the chemical shift (2.48-2.51) parts per million is attributed to the protons of the solvent (DMSO-d6), [32,33] (Fig. 2).
The protons of the aromatic rings are responsible for a multiple signal in the range of 7.02-8.85 ppm, according to the chemical [D6's] 1H-NMR spectra, and , a single signal appears at the chemical shift (6.51) ppm due to the proton of three groups (CH) in the thiazolidinone ring, and a single signal appears at the chemical shift (4.04) ppm due to the protons of tree groups (CH2) in the thiazolidinone ring, and the appearance of a single signal upon chemical displacement (3.34) ppm is attributed to the protons of water (HDO), and a signal appears at the chemical shift (2.492.51) ppm is attributed to the protons of the solvent (DMSO-d6), and a single signal appears at the chemical shift (2.22-2.25) ppm due to the proton of tree groups (CH3) [34, 35].
3.3. Diagnosis and Discussion of Liquid Crystal Behavior
One of the pivotal factors driving the study of liquid crystal behaviour in synthesized compounds is the unique physical and chemical characteristics of these liquid crystalline compounds. Therefore, the liquid crystal behaviour of prepared compounds was investigated using polarizing optical microscopy (POM) equipped with an electric heater. This involved taking a quantity of the material to be studied and placing it on a glass slide, then observing the thermal transitions of liquid crystalline phases during heating. Subsequently, the nature of these transitions was identified, and the thermal stability of each transition was studied. To understand the nature of these transitions and their thermal stability, it is essential to grasp some general concepts about the nature of the prepared compounds and the probability of liquid crystalline phases appearing in them [36, 37].
Organic compounds were prepared, one with a rod-like shape and the other discotic, both being morphologies indicative of liquid crystalline phases. Mesogenic units were prepared from a molecular core consisting of more than two aromatic rings connected by groups enhancing electronic delocalization
along the molecular axis, represented by groups (-C=N, -OC=O). The liquid crystal behaviour of prepared compounds was monitored using POM to determine the liquid crystalline transitions and to study the nature of these transitions and their thermal stability. It was observed that most discotic compounds exhibited liquid crystalline transitions with high thermal stability, depending on the nature of the mesogenic units for each compound [38, 39]. When studying the liquid crystal behaviour of compounds under investigation, it was noticed that compounds with rod-like mesogenic units did not exhibit liquid crystalline properties, possibly due to the ratio of molecular length to width not falling within the range (L/d > 4.0-6.4), where d is the
average molecular diameter and L is the molecular length [40,41]. The appearance of discotic liquid crystal phases in compounds might be attributed to the mesogenic unit's disclike structure possessing a disparate radial axis, with the molecular diameter significantly larger than the longitudinal axis represented by the disc thickness [42]. Therefore, the appearance of liquid crystalline properties in discotic compounds is attributed to the presence of a proper structure of mesogenic units composed of the molecular core containing more than two aromatic rings linked by bonds enhancing electronic delocalization along the molecular axis.
Heating
Rectangular |_
I & Hexagonal N nematic
Cooling
D1
D2
D3
D4
¡H
f j
4 ^ Str • X
Fig. 3. Heating cooling phases of liquid crystal of the generated compound D1 to D4 showing N
nematic, rectangular, and hexagonal shapes.
Furthermore, the presence of polar forces and side attraction forces between terminal groups increasing terminal bonding mesogenic unit molecules favour the appearance
of rectangular and homogeneous liquid crystal phases. Additionally, the presence of polar terminal groups increases terminal bonding forces favoring the appearance of nematic liquid crystal phases in the compound. It was observed that the thermal stability of the nematic liquid crystal phase (AN) increases with the presence of polar terminal groups, as the presence of groups like (NO2, OCH3) at the molecule's end provides greater thermal stability to the nematic phase compared to groups like (H, CH3) [43, 44]. Studying the produced compounds' liquid crystal characteristics revealed that the
transitions were monotropic and only happened when the compounds heated, except in compound (D1), where they appeared during both heating and cooling, indicating an enantiotropic property [45, 46]. Table (3) illustrates the transition temperatures for the compounds under study, and (Figure 3) depicts images of the liquid crystalline compounds obtained.
Studying the produced compounds' liquid crystal characteristics revealed that the transitions were monotropic and only happened when the compounds heated.
Table 3. Transition temperatures and liquid crystal phases of prepared compounds.
No. Cr Sa Sc N ASa ASc AN
Cr Col.h Col.r N A Col.h A Col.r AN
D1 203 241 258 38 17
208 252 44
D2 180 219 241 39 22
D3 119 134 159 15 25
D4 193 226 33
Cr=Crystal phase Sa, Sc , = Smectic phase N= Nematic phase
4. Conclusions
The prepared compounds were of high purity and this was confirmed by various spectroscopic examinations. The increase in the number of aromatic rings led to an increase in melting points. The absence of crystal phases in some compounds may be due to the effect of
increasing the number of aromatic rings that increased the hardness of the molecule, which prevented the appearance of crystal phases as well as compensated aggregates on the rings, which increase the width of the molecule and thus not align.
References
1. Stephen M.J., Straley J.P. Physics of liquid crystals // Reviews of Modern Physics, 1974, V. 46(4), p. 617. https://doi.org/10.1103/RevModPhys.46.61 7.
2. Alikhanova A.I., Mamedova A.F., Ibadov E.A., Nurullayeva D.R. Preparation and study of copolymer of N, N'-(P-phenylene) bismaleimide with allyl ester of salicylic acid // Chemical Problems, 2023, V. 21(4), p. 361-369. https://doi.org/10.32737/2221-8688-2023-4-361-369.
3. Binnemans K. Ionic liquid crystals // Chemical Reviews, 2005, V. 105(11), p.
4148-204.
https://doi .org/10.1021/cr0400919.
4. Kusabayashi S., Takenaka S. Structure and Properties of Liquid Crystals // Journal of Synthetic Organic Chemistry, 1984, V. 42(1), p. 2-12. https://doi .org/10.5059/yukigoseikyokaishi. 42.2.
5. Aslanova E.T., Mamedov E.T, Rashidova M.N., Garayeva A.A., Atakishiyeva V.O. Synthesis of new thermostable polyhydroxyester on the basis of 2-hydroxypropyl-1, 3-bis-carboxymethylesterosulfoimide of
saccharin-6-carboxylic acid // Chemical Problems, 2023, V. 21(2), p. 140-145. DOI: 10.32737/2221-8688-2023-2-140-145.
6. Huseynov K.Z., Aliyev P.A., Mirzoyeva M.A., Eyvazova I.M., Aliyev N.A. Synthesis of alkoxycarbonylmethyl esters of thioacetic and thiobenzoic acids and their investigation as additives to lubricating oils // Chemical Problems, 2023, V. 21(3), p. 294-300. DOI: 10.32737/2221-8688-20233-294-300.
7. Li S.L., Chen Z.Y., Chen P., Hu W., Huang C., Li S.S., Hu X., Lu Y.Q., Chen L.J. Geometric phase-encoded stimuli-responsive cholesteric liquid crystals for visualizing real-time remote monitoring: humidity sensing as a proof of concept // Light: Science & Applications, 2024, V. 13(1), 27. https://doi.org/10.1038/s41377-023-01360-7.
8. Mathe M.T., Himel M.S., Adaka A., Gleeson J.T., Sprunt S., Salamon P., Jakli A. Liquid Piezoelectric Materials: Linear Electromechanical Effect in Fluid Ferroelectric Nematic Liquid Crystals // Advanced Functional Materials, 2024, V. 34(18), 2314158. https://doi.org/10.1002/adfm.202314158.
9. Wang D., Li Y.L., Chu F., Li N.N., Li Z.S., Lee S.D., Nie Z.Q., Liu C., Wang Q.H. Color liquid crystal grating based color holographic 3D display system with large viewing angle // Light: Science & Applications, 2024, 13(1), 16. https://doi.org/10.1038/s41377-023-01375-0.
10. Rajni B., Rakesh S., Bharti K., Reecha M., Simona C. (). The Prospective of Liquid Crystals in Nano formulations for Drug Delivery Systems // Journal of Molecular Structure, 2021, V. 1245, 131117. 10.1016/j.molstruc.2021.131117.
11. Wang D., Liu S., Wei W., Guo H., Zhang Y., Peng H., Zhou X., Xie X. Holographic Plastics with Liquid Crystals // Macromolecules, 2024, V. 57(6), p. 255773.
https://doi .org/10.1021/ acs.macromol.3c02 011.
12. Zhang C., Chen G., Zhang K., Jin B., Zhao Q., Xie T. Repeatedly Programmable
Liquid Crystal Dielectric Elastomer with Multimodal Actuation // Advanced Materials, 2024, V. 36(16), 2313078. https://doi.org/10.1002/adma.202313078.
13. Durur H., Yoku§ A., Duran S. Investigation of exact soliton solutions of nematicons in liquid crystals according to nonlinearity conditions // International Journal of Modern Physics B, 2024, V. 38(4), 2450054.
https://doi.org/10.1142/S021797922450054 1.
14. Bisoyi H.K., Kumar S. Discotic nematic liquid crystals: science and technology // Chemical Society Reviews, 2010, V. 39(1), p. 264-85. DOI: 10.1039/B901792P.
15. Dalaf A.H. Synthesis and Characterization of Some Quartet and Quinary Hetero cyclic Rings Compounds by Traditional Method and Microwave Routes Method and Evaluation of Their Biological Activity // M. Sc. Thesis, Tikrit University, Tikrit, Iraq, 1-94.
16. Jebur M.H., Albdere E.A., Al-Hussainawy M.K., Alwan S.H. Synthesis and characterization of new 1, 3-Oxazepine-4, 7-dione compounds from 1, 2-diaminobenzene // Int. J. Health Sci., 2022, No 6, p. 4578-89. https://doi.org/10.53730/ijhs.v6nS4.9123.
17. Dalaf A.H., Jumaa F.H., Jabbar S.A. Synthesis and Characterization of some 2, 3-dihydroquinozoline and evaluation of their biological activity // Tikrit Journal of Pure Science, 2018, V. 23(8), p. 66-76. https://doi.org/10.25130/tjps.v23i8.545.
18. Jabar S.A., Hussein A.L., Dalaf A.H., Aboud H.S. Synthesis and characterization of azetidine and oxazepine compounds using ethyl-4-((4-bromo benzylidene) amino) benzoate as precursor and evalution of their biological activity // Journal of Education and Scientific Studies, 2020, V. 5(16), p. 39-52
19. Abd I.Q., Ibrahim H.I., Jirjes H.M., Dalaf A.H. Synthesis and identification of new compounds have antioxidant activity beta-carotene, from natural auxin phenyl acetic acid // Research Journal of Pharmacy and Technology, 2020, V. 13(1), p. 40-6.
https://doi.org/10.5958/0974-360X.2020.00007.4.
20. Dalaf A.H., Jumaa F.H. Synthesis, identification and assess the biological and laser efficacy of new compounds of azetidine derived from benzidine // MJPS. 2020, V. 7(2), p. 12-25. DOI: 10.52113/2/07.02.2020/12-25.
21. Saleh R.H., Rashid W.M., Dalaf A.H., Al-Badrany K.A., Mohammed O.A. Synthesis of some new thiazolidinone compounds derived from schiff bases compounds and evaluation of their laser and biological efficacy // Ann Trop & Public Health, 2020, V. 23(7), p. 1012-31. http://doi.org/10.36295/ASR0.2020.23728.
22. Yass I.A., Aftan M.M., Dalaf A.H., Jumaa F.H. Synthesis and identification of new derivatives of bis-1, 3-oxazepene and 1, 3-diazepine and assess the biological and laser efficacy for them // InThe Second International & The Fourth Scientific Conference of College of Science -Tikrit University. (P4) 2020, p. 77-87.
23. Salih B.D., Dalaf A.H., Alheety M.A., Rashed W.M., Abdullah I.Q. Biological activity and laser efficacy of new Co (II), Ni (II), Cu (II), Mn (II) and Zn (II) complexes with phthalic anhydride // Materials Today: Proceedings, 2021, V. 43, p. 869-74. https://doi.org/10.1016/j.matpr.2020.07.083
24. Khalaf S.D., Ahmed N.A., Dalaf AH. Synthesis, characterization and biological evaluation (antifungal and antibacterial) of new derivatives of indole, benzotriazole and thioacetyl chloride // Materials Today: Proceedings, 2021, V. 47, p. 6201-10. https://doi.org/10.1016/j.matpr.2021.05.160
25. Dalaf A.H., Jumaa F.H., Salih H.K. Preparation, characterization, biological evaluation and assess laser efficacy for new derivatives of imidazolidin-4-one // International Research Journal of Multidisciplinary Technovation, 2021, V. 3(4), p. 41-51. https://doi.org/10.21608/ejchem.2021.5529 6.3163.
26. Rabah M.A., El Qady O.A., Abou El Kassem S.A. Recovery of Metal Values from Secondary Resources // Int. Res. J. Multidiscip. Technovation, 2022, V. 4(2), p. 11-20. https://doi .org/10.54392/irjmt2222.
27. Dalaf A.H., Jumaa F.H., Aftana M.M., Salih H.K., Abd I.Q. Synthesis, Characterization, Biological Evaluation, and Assessment Laser Efficacy for New Derivatives of Tetrazole // InKey Engineering Materials, 2022, V. 911, p. 3339. https://doi.org/10.4028/p-6849u0.
28. Alasadi Y.K., Jumaa F.H., Dalaf A.H., Shawkat S.M., Mukhlif M.G. Synthesis, Characterization, and Molecular Docking of New Tetrazole Derivatives as Promising Anticancer Agents // Journal of Pharmaceutical Negative Results, 2022, V. 13(3), p. 513-22. https://doi.org/10.47750/pnr.2022.13.03.07 9.
29. Dalaf A.H., Jumaa F.H., Yass I.A. Synthesis, characterization, biological evaluation, molecular docking, assess laser efficacy, thermal performance and optical stability study for new derivatives of bis-1, 3-oxazepene and 1, 3-diazepine // InAIP Conference Proceedings, 2022, 2394, 040037. https://doi.org/10.1063/5.0121213.
30. Alasadi Y.K., Jumaa F.H., Dalaf AH. Synthesis, identification, antibacterial activity and laser effect of new derivatives of bis-1, 3-oxazepene-4, 7-dione and 1, 3-diazepine-4, 7-dione. InAIP Conference Proceedings, 2022, 2394, 040019. https://doi.org/10.1063/5.0121358.
31. Toma M.A., Ibrahim D.A., Dalaf A.H., Abdullah S.Q., Aftan M.M., Abdullah E.Q. Study the adsorption of cyclopentanone on to natural polymers // InAIP Conference Proceedings, 2022, 2394, 040007. https://doi.org/10.1063Z5.0121209.
32. Hamad A.M., Atiyea Q.M., Hameed D.N., Dalaf A.H. Green synthesis of copper nanoparticles using strawberry leaves and study of properties, anti-cancer action, and activity against bacteria isolated from Covid-19 patients // Karbala International Journal of Modern Science, 2023, V. 9(1),
12. https://doi.org/10.33640/2405-
609X.3275.
33. Jassim A.S., Dalaf A.H., Abdullah T.F. Studying the Biological Activity and Properties of Copper Nanoparticles Prepared by Pulsed Laser Ablation in Liquid // InThe Third International and The Fifth Scientific Conference for College of Science - Tikrit University, 2022, V. 25(1), p. 213-221.
34. Mohammed L.J., Hamad A.M., Atiyea Q.M., Jwair W.A., Dalaf A.H., Jasim A.S., Elsaigher S.M., Ragab A., Hassan Z.H. In vitro Comparison of the Effect of Zinc Oxide Nanoparticles and Hibiscus sabdariffa Extract on Streptococcus mutans Isolated from Human Dental Caries // InThe Third International and The Fifth Scientific Conference for College of Science-Tikrit University, 2022, V. 2(2), p. 5-14.
35. Najm R.S., Shannak Q.A., Dalaf AH. Synthesis and Decoration of Aromatic Derivatives Nano Platelets by the Electric Method // Azerbaijan Pharmaceutical and Pharmacotherapy Journal, 2023, V. 22(2), p. 92-7. https://doi.org/10.61336/appj/22-2-22.
36. Ruan K., Zhong X., Shi X., Dang J., Gu J. Liquid crystal epoxy resins with high intrinsic thermal conductivities and their composites: A mini-review // Materials Today Physics, 2021, V. 20, 100456. https://doi.org/10.1016/j.mtphys.2021.1004 56.
37. Lv P., Yang X., Bisoyi H.K., Zeng H., Zhang X., Chen Y., Xue P., Shi S., Priimagi A., Wang L., Feng W. Stimulus-driven liquid metal and liquid crystal network actuators for programmable soft robotics // Materials Horizons, 2021, V. 8(9), p. 247584. https://doi.org/10.1039/D1MH00623A.
38. Li Y.L., Li N.N., Wang D., Chu F., Lee S.D., Zheng Y.W., Wang Q.H. Tunable liquid crystal grating based holographic 3D display system with wide viewing angle and large size // Light: Science & Applications, 2022, V. 11(1), p. 188. https://doi.org/10.1038/s41377-022-00880-
y.
39. Kim I., Ansari M.A., Mehmood M.Q., Kim W.S., Jang J., Zubair M., Kim Y.K., Rho J. Stimuli-responsive dynamic metaholographic displays with designer liquid crystal modulators // Advanced Materials, 2020, V. 32(50), 2004664. https://doi.org/10.1002/adma.202004664.
40. Zhang J., Uzun S., Seyedin S., Lynch P.A., Akuzum B., Wang Z., Qin S., Alhabeb M., Shuck C.E., Lei W., Kumbur EC. Additive-free MXene liquid crystals and fibers // ACS central science, 2020, V. 6(2), p. 254-65. https://doi .org/10.1021/acscentsci.9b01217.
41. Esteves C., Ramou E., Porteira A.R., Moura Barbosa A.J., Roque A.C. Seeing the unseen: the role of liquid crystals in gas-sensing technologies // Advanced optical materials, 2020, V. 8(11), 1902117. https://doi.org/10.1002/adom.201902117.
42. Uchida J., Soberats B., Gupta M., Kato T. Advanced functional liquid crystals // Advanced Materials, 2022, V. 34(23), 2109063.
https://doi.org/10.1002/adma.202109063.
43. Yin K., Hsiang E.L., Zou J., Li Y., Yang Z., Yang Q., Lai P C., Lin C.L., Wu S T. Advanced liquid crystal devices for augmented reality and virtual reality displays: principles and applications // Light: Science & Applications. 2022, V. 11(1), 161. https://doi.org/10.1038/s41377-022-00851-3.
ASTERiZM BiRL9§M9L9RENiN SiNTEZi, XARAKTERiSTiKASI V9 KRiSTAL
XUSUSiYYOTLaRiNiN OYR9NiLM9Si
Dardaa A. ibrahim, Hanaa K. Salih
Tikrit Universiteti, Elm Kolleci, Kimya Bolmdsi, Tikrit, iraq e-mail: [email protected]
Xülasa: Bu tadqiqat asterizm qurulu§lu birla§malarinin (D1-D6) mütlaq etanolda hall edilmi§ 1 mol benzol 1,3,5-triol va 3 mol hazirlanmi§ pentasiklik halqali efir toramalari ila reaksiyasi vasitasila sintezina hasr olunmu§dur. Birla§malarin strukturlari infraqirmizi spektroskopiya va proton nüva maqnit rezonans spektroskopiyasi kimi fiziki va spektroskopik üsullardan istifada etmakla tasdiq edilmi§dir. Bundan alava, alinmi§ birla§malarin arima noqtalari va tamizlik daracalari müayyan edilmi§dir. Reaksiyanin gedi§i Nazik Ortük Xromatoqrafiyasi (TLC) ila mü§ahida edilmi§dir. Bir sira birla§malarin maye kristal fazalari polyar optik mikroskop (POM) vasitasila tadqiq edilmi§dir. A?ar sozlar: asterizm birla§malari, efirlar, maye kristallar.
СИНТЕЗ, ХАРАКТЕРИСТИКА И ИЗУЧЕНИЕ КРИСТАЛЛИЧЕСКИХ СВОЙСТВ
СОЕДИНЕНИЙ АСТЕРИЗМА
Дардаа А. Ибрагим, Ханаа К. Салих
Кафедра химии, Колледж наук, Университет Тикрита, Тикрит, Ирак
e-mail: [email protected]
Резюме: Это исследование включает синтез соединений со звездоподобной структурой (D1-D6) посредством реакции 1 моля бензол-1,3,5-триола с 3 молями приготовленных производных пентациклического кольца эфира, растворенных в абсолютном этаноле. Достоверность структур соединений была подтверждена с использованием физических и спектроскопических методов, таких как инфракрасная спектроскопия и протонная ядерная магнитно-резонансная спектроскопия. Кроме того, были определены точки плавления и чистота, а ход реакции контролировался с помощью тонкослойной хроматографии (ТСХ). Жидкокристаллические фазы некоторых приготовленных соединений были исследованы с помощью поляризационного оптического микроскопа (ПОМ). Ключевые слова: соединение астеризма, эфиры, жидкие кристаллы.
