154845-75-7Relevant academic research and scientific papers
Synthesis and characterization of novel 4-benzyloxyphenyl 4-[4-(n-dodecyloxy) benzoyloxy]benzoate liquid crystal
Balkanli, Emine,?akar, Fatih,Ocak, Hale,Cankurtaran, ?zlem,Bilgin Eran, Belk?z
, p. 71 - 81 (2021/03/16)
Liquid crystal (LC) compound 4-Benzyloxyphenyl 4-[4-(n-dodecyloxy)benzoyloxy]benzoate (BDBB) was prepared and characterized. Inverse gas chromatography (IGC) was to be a beneficial analysis method for the research of thermodynamic characteristics of the new LC. Acetate and alcohol isomers were used to examine LC selectivity via the IGC technique at temperatures between 333.2 K and 483.2 K. The retention diagrams of n-heptane, n-octane, n-nonane, n-decane, undecane, dodecane, tridecane, n-butyl acetate, isobutyl acetate, ethyl acetate, n-propylbenzene, isopropylbenzene, ethylbenzene, chlorobenzene, and toluene on BDBB were plotted with temperatures of 483.2-493.2 K. Flory-Huggins interaction parameter and weight fraction activity coefficient at infinite dilution were researched for BDBB.
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.
Effect of regioisomerism on the self-assembly, photophysical and gelation behavior of aroylhydrazone based polycatenars: Synthesis and characterization
Kanth, Priyanka,Singh, Hemant Kumar,Kumar, Vijay,Singh, Sachin Kumar,Rao, D.S. Shankar,Prasad, S. Krishna,Singh, Bachcha
, (2019/07/02)
In this paper we report five series of aroylhydrazone based polycatenars differing from each other in number and position of alkoxy chains on one end of the core; keeping other end the same. A systematic variation in the structures was carried out to understand the effect of position and chain length on the mesophase behavior. In the case of single alkoxy chain at 4-position, there is a transition from Smectic C to Smectic A mesophase during cooling and Smectic A to Smectic C transition in heating cycle in all the homologues except n = 6 & n = 8. In the case of two alkoxy chains at 3-, 5-positions, the compounds are non-mesogenic in nature. On changing the position of alkoxy chains from 3-, 5-positions to 3-, 4-positions, intermolecular forces weaken and these compounds become liquid crystalline and show columnar rectangular mesophase resulting from the effect of regioisomerism. Moving on to the series with three alkoxy chains, it was observed that 2-, 3-, 4-trialkoxy substituted compounds exhibit columnar rectangular mesophase except lower chain length (n = 6 & 8) while 3-, 4-, 5-trialkoxy substituted aroylhydrazones show columnar rectangular mesophase; except n = 10 which shows columnar oblique mesophase. Thus it was established that on increasing density of alkoxy chains around one terminal, mesophase changes from smectic to columnar mesophase. Temperature dependent Raman studies confirm the presence of intermolecular hydrogen bonding. Further, effect of substitution pattern did not show much influence on the photophysical properties of the mesogenic series in solid and solution state. However, the non-mesogenic series showed a different absorption and emission transition from the mesogenic series in solid and solution state. Solid state fluorescence studies show almost similar emission maxima in all the series. However, it was also noticed that non-mesogenic series show maximum red shifted emission maxima in solid state as compared to that of solution. All the series showed good gelation properties with less than 1% CGC (wt%) suggesting the strong ability of molecules to form gel. These H-bonded liquid-crystalline gels have immense potential for applications in emissive displays.
Star-shaped fluorescent liquid crystals derived from s-triazine and 1,3,4-oxadiazole moieties
Pradhan, Balaram,Pathak, Suraj Kumar,Gupta, Ravindra Kumar,Gupta, Monika,Pal, Santanu Kumar,Achalkumar, Ammathnadu S.
supporting information, p. 6117 - 6130 (2016/07/06)
Star-shaped molecules with a central triazine core appended with three 1,3,4-oxadiazole arms have been designed with the variation in the number, length and pattern of peripheral chain substitution. These compounds were investigated for their thermal, electrochemical and photophysical behavior. These nonconventional molecules stabilized wide range columnar phases and demonstrated how one can tune the liquid crystal self-assembly through simple structural modification. The photophysical properties of these star shaped molecules are extremely dependent on the number and pattern of peripheral chain substitution. These compounds exhibit blue and green luminescence in the solid/liquid crystal state. The ability to overcome aggregation induced quenching is due to the favorable packing of these molecules in the solid state. These solid-state emissive materials with good thermal stability and lower band gap may find applications in the construction of emissive displays and organic lasers.
Triketonate difluoroboron complexes. Substitution-dependent liquid crystal and photophysical properties
Sánchez, Ignacio,Fernández-Lodeiro, Adrián,Oliveira, Elisabete,Campo, José Antonio,Torres, M. Rosario,Cano, Mercedes,Lodeiro, Carlos
, p. 184 - 200 (2016/09/07)
Novel alkyloxyphenyl-substituted β,δ-triketonate difluoroboron complexes have been efficiently synthesised and thoroughly characterised. Significant features such as liquid crystal behaviour and solid and solution fluorescence are observed in all cases. The mesomorphism was determined by the presence of one, two or three alkyl chains in each substituent aromatic group of the triketonate ligand. So, smectic C mesophases were found for compounds carrying two lateral chains, each of them located at one of each phenyl substituent, while the presence of four or six chains at the whole molecule gave rise to smectic A or discotic lamellar and hexagonal columnar mesophases, respectively. Fluorescence in the solid state and in solution is again proved to be dependent on the ligand substitution as well as to be maintained in the mesophase. These multifunctional materials also present luminescent sensor activity towards Hg2+ and Cu2+.
Synthesis, characterization and mesomorphic investigations of ester-substituted aroylhydrazones possessing a lateral hydroxyl group
Singh, Sachin Kumar,Singh, Hemant Kumar,Nandi, Rajib,Kumar, Vijay,Tarcea, Nicolae,Popp, Jürgen,Singh, Ranjan K.,Singh, Bachcha
, p. 99 - 112 (2014/04/17)
The synthesis, characterization and investigation of a new liquid crystalline series of ester containing aroylhydrazones with a lateral hydroxyl group, N-[4-(4′-alkoxy)benzoyloxy-2-hydroxy-benzylidene]-N′- [4″-alkoxybenzoyl]hydrazine (Cm,nLH), with the same or different peripheral alkoxy chains, and some of their nickel(II) and copper(II) complexes are described. All the ligands, except those with no terminal chains on either end of the molecule, exhibit an enantiotropic SmC mesophase, as evidenced by polarizing optical microscopy and differential scanning calorimetric studies. It has been found that addition of a lateral hydroxyl group along with ester-substitution to the aroylhydrazone core increases the mesomorphic as well as thermal stability of the ligands. Also, the coordination of Ni2+ and Cu2+ with the aroylhydraozone core inhibits the mesomorphic potential of the ligands. A temperature dependent Raman study of one of the members, C12,12LH (m = n = 12) has been made to identify phase transitions and to understand the molecular rearrangement as a result of changes in intermolecular interactions at the phase transition. DFT calculations have been performed to obtain the stable electronic structure of the ligand (C6,6LH) and its nickel(II) complex.
Synthesis and study of vitrescent materials based on the alkoxybenzoic acids derivatives and triethanolamine
Gruzdev,Akopova,Frolova
, p. 652 - 658 (2013/07/05)
Fifteen new branched triethanolamine esters of the benzoic acid derivatives were designed and the mesomorphism typical of discotic mesogens was forecast for them. In eight of the obtained compounds a manifestation of liquid crystal properties was predicted, for four derivatives equiprobable prognosis was given, and only three compounds were predicted not to form a mesophase. The obtained esters were characterized by elemental analysis, NMR and IR spectroscopy, gas chromatography-mass spectrometry. The main thermal characteristics that allow accounting for their phase behavior were determined.
New mesomorphic benzothiazol derivatives: Synthesis and characterization
Koh, Teck-Ming,Ha, Sie-Tiong,Yeap, Guan-Yeow,Lin, Hong-Cheu
, p. 926 - 928 (2013/09/24)
In this paper, the synthesis of new mesomorphic benzothiazolyl derivatives, 6-ethoxy-2-[4-(4-alkyloxybenzoyloxy)benzylidenamino]benzothiazoles, is presented. The structures of the title compounds were elucidated using spectroscopic techniques, such as FT-IR, NMR (1H and 13C), elemental analysis and EI-MS. The mesomorphic behaviours of these compounds were determined by differential scanning calorimetric and polarizing optical microscopic techniques. Compounds exhibited nematic and tilted smectic phases upon heating from crystal phase. An obvious odd-even effect was observed in this homologous series.
Hydrophobically assisted separation-friendly Mitsunobu reaction
Guo, Jian,Lu, Yu-Jiao,Zhang, Li,Ye, Xin-Shan
supporting information; experimental part, p. 1696 - 1700 (2012/07/17)
A separation-friendly Mitsunobu reaction using hydrophobic-tagged acids is reported. Commercially available or simply prepared and recyclable hydrophobic-tagged acids can react with various alcohols to afford the target products in high yield with easy purification based on C-18 silica solid-phase extraction or normal silica gel filtration. Georg Thieme Verlag Stuttgart · New York.
Synthesis and mesomorphic evaluation of new calamitic liquid crystals containing benzothiazole core
Koh, Teck Ming,Ha, Sie Tiong,Lee, Teck Leong,Lee, Siew Ling,Yeap, Guan Yeow,Lin, Hong Cheu,Subramaniam, Ramesh T.
scheme or table, p. 619 - 622 (2012/02/01)
The design and synthesis of new calamitic benzothiazole-based liquid crystals, 2-[4-(4-alkyloxybenzoyloxy)-phenyl]benzothiazoles are presented. The target compound was characterized using spectroscopic techniques, such as FT-IR, NMR (1H and 13C), microanalysis and EI-MS. The liquid crystalline behaviours of these compounds were thoroughly examined by differential scanning calorimetry and polarizing optical microscope techniques. These materials exhibited enantiotropic nematic phase with high thermal stability (>168 °C). Smectic A phase starts to emerge as monotropic (metastable) phase from C10 member and changes into enantiotropic (stable) phase from C12 and persists up to C16 members.
