188685-17-8Relevant articles and documents
Synthesis, Thermal, and Optical Properties of Tris(5-aryl-1,3,4-oxadiazol-2-yl)-1,3,5-triazines, New Star-Shaped Fluorescent Discotic Liquid Crystals
Tober, Natalie,Rieth, Thorsten,Lehmann, Matthias,Detert, Heiner
, p. 15295 - 15304 (2019)
The synthesis of tris(aryloxadiazolyl)triazines (TOTs), C3-symmetrical star-shaped mesogenes with a 1,3,5-triazine center, 5-phenyl-1,3,4-oxadiazole arms, and various peripheral alkoxy side chains is reported. Threefold Huisgen reaction on a ce
Exceptional dual fluorescent, excited-state intramolecular proton-transfer (ESIPT) columnar liquid crystals characterized by J-stacking and large Stokes shifts
Kanakala, Madhu Babu,Yelamaggad, Channabasaveshwar V.
, (2021/03/19)
Excited-State Intramolecular Proton-Transfer (ESIPT) fluorophores are emerging as promising future materials for electronic and biotechnological applications. ESIPT columnar (Col) liquid crystals (LCs) have been especially projected as the apt materials for advanced technological endeavors. But, there are hardly any explorations in this direction and thus, needing immediate attention. Herein we report on the synthesis, characterization, and ESIPT activity of a homologous series of novel phasmidic bis(N-salicylideneaniline) Col LCs. Optical microscopic, calorimetric and powder X-ray diffraction (XRD) studies evidence the occurrence of hexagonal columnar (Colh) phase having p6mm symmetry where the constituent slices result from the self-assembly of a pair of mesogens in a side-by-side manner facilitated by intense longitudinal π-π interactions. X-ray data confirm the absence of both directionally correlated tilting of the slices and transverse core-core interactions within the columns. Fluorescence probing clearly evidence the ESIPT occurring not only in DCM solution of the mesogens but also in their three-condensed states viz., solid, liquid crystal, and isotropic liquid phase; in general, two archetypal emission bands at ~430 nm (weak) and ~ 630 nm (strong) with large Stokes shifts (250–275 nm) of ESIPT phenomenon have been observed. The slow shift of emission maxima of the ESIPT fluorescence as a function of decreasing temperature without photoluminescence quenching coupled with the estimated tilt angle (?) of the slices normal to the columnar axis (37 to 42o), from the XRD data, confirm the formation of so-called Scheibe or J-aggregates. The redox activity, metal ion sensing ability, and solvatochromism of the mesogens have also been investigated. The study suggests that these ESIPT Col LCs with band-gap of about 3 eV can be regarded as wide-bandgap semiconducting materials having the electronic characteristics falling between those of conventional semiconductors and insulators.
Impact of substitution pattern and chain length on the thermotropic properties of alkoxy-substituted triphenyl-tristriazolotriazines
Detert, Heiner,Glang, Stefan,Haspel, Tobias,Lehmann, Matthias,Limbach, Daniel,Rieth, Thorsten,Schupp, Niklas,Sperner, Marcel,Tober, Natalie,Wicker, Philipp
, (2021/06/14)
Tristriazolotriazines (TTTs) with a threefold alkoxyphenyl substitution were prepared and studied by DSC, polarized optical microscopy (POM) and X-ray scattering. Six pentyloxy chains are sufficient to induce liquid-crystalline behavior in these star-shap
Fluorescent columnar bis(boron difluoride) complexes derived from tetraketonates
Chen, Ya-Wen,Lin, Yen-Chun,Kuo, Hsiu-Ming,Lai, Chung K.
, p. 5465 - 5477 (2017/07/10)
Three new series of bis-(boron difluoride) complexes 1a-c derived from substituted tetraketonates 2a-c are reported, and their mesomorphic and optical properties have been investigated. Two single crystals of mesogenic ligand 2a (n = 6) and nonmesogenic d
Self-assembly of hekates-tris(N -salicylideneaniline)s into columnar structures: Synthesis and characterization
Achalkumar, Ammathnadu S.,Hiremath, Uma S.,Rao, D. S. Shankar,Prasad, S. Krishna,Yelamaggad, Channabasaveshwar V.
, p. 527 - 544 (2013/03/13)
Two series of new, photoluminescent star-shaped discotic liquid crystals, recently termed as "hekates", derived from tris(N-salicylideneaniline) s (TSANs), were synthesized by the facile threefold condensation of 3,4-bis(alkoxy)phenyl 4-aminobenzoates/3,4,5-tris(alkoxy) phenyl 4-aminobenzoates with 1,3,5-triformylphloroglucinol and characterized. These two series of discotics with six and nine peripheral n-alkoxy tails were especially designed and accomplished to understand the relation between mesomorphic/photophysical properties and molecular structure. Proton NMR spectral analysis revealed their existence as an inseparable mixture of two keto-enamine tautomeric forms featuring C3h and Cs rotational symmetries. A systematic study into the thermotropic liquid crystal behavior using polarizing optical microscopy, differential scanning calorimetry, and X-ray scattering confirmed the presence of columnar (Col) phase in vast majority of the TSANs prepared. The two-dimensional (2D) lattices of these fluid columnar phases were found to be characteristic of hexagonal Col (Col h), rectangular Col (Colr), or oblique Col (Col ob) phases depending on the number/length of the peripheral flexible chains. The stabilization of the Colob phase, a less commonly found fluid columnar structure, and the first of its kind in TSAN systems, implies very intensive intermolecular (face-to-face) interactions among the TSAN cores within the column. The photophysical properties were investigated both in solution and the columnar states by UV-vis absorption and photoluminescence; markedly, the solution state emits light in the blue region. The light-emitting ability of the Col phase is particularly significant given the possibility that, in such cores, the protons and electrons interact with each other through the H-bonding environment.
Mesomorphism and luminescence properties of platinum(II) complexes with tris(alkoxy)phenyl-functionalized pyridyl pyrazolate chelates
Liao, Ching-Ting,Chen, Hsiu-Hui,Hsu, Hsiu-Fu,Poloek, Anurach,Yeh, Hsiu-Hsuan,Chi, Yun,Wang, Kang-Wei,Lai, Chin-Hung,Lee, Gene-Hsiang,Shih, Chun-Wei,Chou, Pi-Tai
, p. 546 - 556 (2011/03/21)
A series of new mesomorphic platinum(II) complexes 1-4 bearing pyridyl pyrazolate chelates are reported herein. In this approach, pyridyl azolate ligands have been strategically functionalized with tris(alkoxy)phenyl groups with various alkyl chain length
Gallic esters of 4,5-dinitrocatechol as potential building blocks for thermotropic liquid crystals
Judele, Roxana,Laschat, Sabine,Baro, Angelika,Nimtz, Manfred
, p. 9681 - 9687 (2007/10/03)
A series of unsubstituted and 1,4-disubstituted gallic catecholates 1, 6 and 7 as possible candidates for wedge-shaped mesogens were prepared starting from the respective benzene derivatives 2a-c and gallic esters 5a-h. The mesomorphic properties were inv
Coassembly of a hexagonal columnar liquid crystalline superlattice from polymer(s) coated with a three-cylindrical bundle supramolecular dendrimer
Percec, Virgil,Ahn, Cheol-H.,Bera, Tushar K.,Ungar, Goran,Yeardley, Duncan J.P.
, p. 1070 - 1083 (2007/10/03)
The synthesis and structural analysis of a polymer containing twin- dendritic benzamide side-groups (i.e. poly{N-[3,4-bis(n-dodecan-1-yloxy)- 5(1-methacryloyl-η-undecan-1-yloxy)phenyl]-3,4,5-tris(n-dodecan-1- yloxy)benzamide}) (19) are described. The disc
Tailoring thermotropic cubic mesophases: Amphiphilic polyhydroxy derivatives
Borisch, Konstanze,Diele, Siegmar,Goering, Petra,Kresse, Horst,Tschierske, Carsten
, p. 529 - 543 (2007/10/03)
Novel amphiphilic polyhydroxy compounds [N-(3,4-dialkoxybenzoyl)-1-amino-1-deoxy-D-glucitols (glucamides), N-(3,4-dialkoxybenzoyl)-1-deoxy-1-methylamino-D-glucitols, N-(3,4,5-trialkoxybenzoyl)-1-deoxy-1-methylamino-D-glucitols (N-methylgucamides), 1-benzo
Formation of disordered hexagonal arrangements in bis(β,δ-triketonato)copper(II) complexes
Lai, Chung K.,Chen, Fuh-Gue,Ku, Yu-Ju,Tsai, Chun-Hsien,Lin, Raymond
, p. 4683 - 4687 (2007/10/03)
Two homologous series of 1-(4-alkoxy-2-hydroxyphenyl)-3-(3,4,5-trialkoxyphenyl)propane-1,3-diones and 1-(2-hydroxyphenyl)-3-(3,4,5-trialkoxyphenyl)propane-1,3-diones were prepared by base-catalysed rearrangement of 4-alkoxy-2-(3,4,5-trialkoxybenzoyloxy)ac