15872-48-7Relevant academic research and scientific papers
"Structured Nuclei" of 4-(Octadecyloxy)benzoic Acid Monolayer for Induced Nucleation of 4-Hydroxybenzoic Acid Monohydrate As Determined by Grazing Incidence X-ray Diffraction on the Aqueous Solution
Weissbuch, Isabelle,Berkovic, Garry,Yam, Ruth,Als-Nielsen, Jens,Kjaer, Kristian,et al.
, p. 6036 - 6045 (1995)
A monolayer of 4-(octadecyloxy)benzoic acid at the air-solution interface has been used to induce oriented nucleation of three-dimensional (3-D) crystals of 4-hydroxybenzoic acid (HBA) minohydrate.The two-dimensional (2-D) crystalline structure of this mo
Thermotropic properties of monosubstituted ferrocene derivatives bearing bidentate N-benzoyl-N′-arylthiourea ligands - Novel building blocks for heterometallic liquid crystal systems
Seshadri, Tarimala,Haupt, Hans-Juergen
, p. 1345 - 1350 (1998)
Ferrocene-based derivatives such as 4-{3-[4-(octyloxy)benzoyl]thioureido}phenyl 4-ferrocenylbenzoate and other higher homologues (n = 12,16 and 18; n=length of alkoxy chain) were prepared by reacting 4-alkoxybenzoyl isothiocyanates with the corresponding amines containing the ferrocenyl moiety. Their mesomorphic properties were investigated by means of polarized optical microscopy and differential scanning calorimetry. All the compounds exhibit enantiotropic nematic phases and the nematic range increases with increasing terminal alkyl chain length. On cooling, the nematic phase persists below 0°C in the first three compounds and in the case of n = 18, a phase transformation, possibly to the Sc phase, around 72°C during cooling was observed. In all cases, a glass transition was observed around Tg = 18-35°C, which is remarkable for low molecular mass calamitic metallomesogen systems.
Synthesis and mesomorphic properties of bis ester derivatives of coumarin containing chalcone linkage
Shah, Priyanka,Soni, Rina,Soman, Shubhangi S
, (2021/05/04)
Bis ester derivatives of coumarin containing chalcone linkage with various terminal alkoxy groups were designed, synthesized and characterized. Compounds 11a-m were studied for their mesomorphic properties using polarizing optical microscope & differential scanning calorimetry and photophysical properties using UV-vis & fluorescence spectroscopy. In this particular homologous series, compounds having lower flexible alkoxy chains showed very good mesogenic property with nematic mesophase formation, while analogues with higher chains failed to show any liquid crystalline property. Compound 11a with methoxy group showed very good absorbance and fluorescence as compared to higher chain length analogues.
Synthesis, mesomorphic properties and biological evolution of calamitic-shaped chalcone-based LCs: effect of lateral and terminal group
Dwivedi, Durgesh J.,Thakor, Akshay,Desai, Vipul,Sharma, Vinay S.,Patel
, p. 16 - 32 (2021/05/26)
The mesomorphic properties of linear shaped homologous series based on two linkage group have been designed and synthesized with different side chain substituents (-OR) on the one end of terminal side with presence of lateral nitro group and second terminal iodo substituted group. Novel series consists thirteen members (C1 to C8, C10, C12, C14, C16, C18). Compounds (C1 to C6) showed nonliquid crystalline properties while compound (C7 to C18) displayed smectic and nematogenic mesophase properties. The textures of smectic C and nematic phase are fan, schlieren and droplets type. All these compounds were characterized by spectroscopic techniques such as [FTIR] and 1H Nuclear magnetic resonance [NMR] spectroscopy. The mesomorphic properties of these compounds were observed by POM and further confirmed by DSC and XRD. Chalconyl ester based compounds (C3 to C12) shows good antibacterial as well as antifungal activity compared with corresponding standard drugs.
λ-shaped to T-shaped azo diester mesogens having methyl (–CH3)/methoxy(–OCH3) terminal substituents with trisubstituted benzene
Duan, Yongtao,Koshti, Rohit R.,Kumar Ameta, Rakesh,Patel, H. N.,Sangani, Chetan B.,Tarpada, Umesh P.,Vyas, Akshay,Yao, Yongfang
, (2021/07/12)
A two new homologous series of λ-shape to T-shape mesogenic azo diesters were synthesized, and their thermotropic properties were studied by differential scanning calorimetry and a hot-stage polarizing optical microscope. The difference between these two series is in the structure of terminal substituents methyl (–CH3) for series I and methoxy (–OCH3) for series II at one terminus. Structure variation from λ-shape to T-shape as we go from lower members to higher members is discussed. In the series I, methoxy to n-pentyloxy derivatives are non-mesogenic. n-hexyloxy derivative exhibits only monotropic nematic mesophase. n-heptyloxy to n-dodecyloxy derivatives exhibit monotropic smectic C mesophase. n-tetradecyloxy derivative exhibits enantiotropic SmA mesophase, whereas n-hexadecyloxy derivatives exhibit monotropic Smectic A mesophase. In series II, methoxy to n-hexyloxy derivatives are non-mesogenic. n-heptyloxy and n-octyloxy derivatives exhibit monotropic smectic C mesophase. Smectic A mesophase commences from the n-decyloxy derivative as a monotropic and persists up to the last member synthesized. The mesomorphic properties of the present series were compared with each other and with the structurally related mesogenic homologous series to evaluate the effect of methyl (–CH3)/methoxy (–OCH3) substituents as well as variation in the shape of the molecule by varying the alkoxy chain length of the bulky lateral substituent on mesomorphism.
Naphthoyl hydrazine organic gel factor as well as preparation method and application thereof
-
, (2021/11/06)
The invention relates to a naphthoyl hydrazine organic gel factor and a preparation method and application thereof. Where n is-18; wherein n is-18. The alkoxy benzoic acid and the condensation agent are mixed into a mixed solution, naphthalene carbonylhydrazide is added and the condensation reaction is carried out, and the alkoxy benzoic acid and the condensation agent are subjected to condensation reaction and can be prepared by separation and purification. The organic gel factor is mixed with an organic solvent, is heated and dissolved in a sealed state, and after cooling, an organic gel with fluorine ion responsiveness can be obtained. Compared with the prior art, the preparation method has the advantages of simple preparation process, mild reaction conditions, good gel ability for various organic solvents such as methanol and ethanol, and the like. The fluorinion has a remarkable specific response to fluoride ions in a gel state, and shows a remarkable advantage in the aspect of fluorine ion detection.
Synthesis and characterization of novel rod-like ester-based liquid crystalline homologous series: Effect of tert-butyl tail on mesomorphism
Thakur, Shavi,Patel, Hemant N.
, p. 76 - 89 (2021/04/14)
A new rod-like homologous series consisting twelve compounds with central ester linkage and terminal tert-butyl group, tert-butyl [4-(4’-n-alkoxybenzoyloxy)benzoates] has been synthesized and characterized through standard spectroscopic techniques like UV, FT-IR, 1HNMR, DSC, POM, and XRD. Methoxy and ethoxy derivatives are nonmesogenic. Nematic mesophase commences as enantiotropy from propyloxy derivative and persists up to the octadecyloxy derivatives. Smectic A mesophase commences as monotropy from propyloxy to the octadecyloxy derivatives. The mesomorphic properties of present series are compared with other structurally related series to evaluate the effect of terminal tert-butyl group on mesomorphism. Two derivatives are subjected to in?vitro antimicrobial activity.
Photoconductive bent-core liquid crystalline radicals with a paramagnetic polar switchable phase
Shivakumar, Kilingaru I.,Pociecha, Damian,Szczytko, Jacek,Kapu?ciński, Szymon,Monobe, Hirosato,Kaszyński, Piotr
, p. 1083 - 1088 (2020/02/05)
A series of self-organizing bent-core derivatives 1[12,n], containing a highly π-delocalized stable radical as the central angular structural element, is described. The planarity of the open-shell core permits efficient π-π stacking, which results in the formation of B2 and soft crystalline phases above 100 °C. Optical, XRD and dielectric analyses of 1[12,12] indicate that the ground state of the observed B2 phase is polar antiferroelectric of type SmCAPA exhibiting tristable electro-optical switching. SQUID and EPR measurements revealed strong antiferromagnetic spin-spin exchange interactions below the isotropic phase, which have been estimated at θ = -46 cm-1 with the Curie-Weiss law. Transient photoconductivity was observed in the B2 phase with a hole carrier mobility μh of 1.4 × 10-4 cm2 V-1 s-1
Dependence of mesomorphism on terminal polar group in novel azoester series
Kher, Seema N.,Prajapati,Makwana,Chandra, Raviprakash S.
, p. 44 - 53 (2019/10/14)
Novel homologous series 4-(4′-n-alkoxy benzoyloxy) napthyl azo 4″–bromo benzenes, consisted of 11 members of a series. All the 11 members (ethoxy to hexadecyloxy) except hexadecyloxy are only enantiotropically nematogenic without exhibition of any smectogenic character. Transition temperatures and the textures are determined by an optical polarizing microscopy equipped with a heating stage. Textures of a nematic phase are threaded or schlieren. Analytical and spectral data supported the molecular structure of homologs. Transition curves viz., solid-nematic and nematic-isotropic showing phase behavior of the mesophase in a phase diagram behave in normal manner. Alternation of transition temperatures is exhibited by N–I transition curve. Thus, novel series is entirely nematogenic and high ordered melting type. Thus, synthesis of a novel azoester homologous series is carried out with a view to understand and establish the effect of molecular structure on Liquid crystal (LC) behaviors of a substance.
“Effect of the linking unit on the calamitic-shaped liquid crystal: a comparative study of two homologous series of benzoate and cinnamate linked compounds”
Kashyap, Dinesh,Patel, Sunil,Prajapat, Varsha,Sharma, Vinay,Vasava, Dilip
, p. 58 - 70 (2019/08/28)
Two homologous series based on three linking groups have been synthesized and well characterized by elemental analyses and spectroscopic techniques such as Fourier transform infrared [FT-IR] and proton magnetic resonance magnetic resonance [1H NMR] spectroscopy. The mesomorphic properties of these compounds were observed by using optical polarized microscopy (POM) and confirmed by differential scanning calorimetry (DSC) analysis. In this present investigation, we have synthesized two homologous series viz. (E)-4-(3-(4-(tetra decanoyloxy) phenyl) acryloyl) phenyl-4-n-alkoxy benzoate (Series-1) and 4-((E)-3-(4-(((E)-3-(4-n-alkoxy phenyl) acryloyl) oxy) phenyl)-3-oxo prop-1-en-1-yl) phenyl tetradecanoate (Series-2). Both of the series are differing with respect to the first linking group. All the homologous in following series displays LC properties on heating as well as cooling condition except first four homologous (C1 to C4) in series-1 and six homologous (C1 to C6) in series-2. To get more insights, the HOMO, LUMO studies are carried out which supports intramolecular charge transfer interactions in this class of mesogens.
