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A series of new calamitic liquid crystals, 4-[3-(pyridin-4-yl)prop-2-enoyl]phenyl 4-alkyloxybenzoates, comprising a pyridyl core, ester–chalcone central linkage and terminal alkyloxy chain were synthesized and characterized. This series consists of four members that differ by the length of the alkyloxy chain (CnH2n+1O, where n = 10, 12, 14, 16). The structures of the title compounds were elucidated using spectroscopic and spectrometric techniques, such as FT-IR, NMR (1H and 13C) and EI-MS. The mesomorphic properties were studied using differential scanning calorimetry and optical polarizing microscopy. The decyloxy-containing compound was found to be non-mesogenic, whilst the compounds containing n-dodecyloxy to n-hexadecyloxy chains exhibited an enantiotropic smectic A phase with a fan-shaped texture. From the structure–property relationship study, it was proposed that the number of carbons in the alkyloxy chain must be at least 12 (n ≥ 12) to generate the smectic phase in the corresponding substituted ArCOOArCOCHCHC5H4N compounds.

A series of elongated Schiff base esters containing three aromatic rings with hexadecanoyl chain as one of the terminal group and various R substituents (R = CN, OH, SH, and NO2) at the other end of molecule were prepared, and their structures were confirmed via physical measurement. The thermotropic properties of these compounds were investigated via differential scanning calorimetry and polarizing optical microscopy. The thermal data indicate that all of these compounds exhibit mesomorphic properties. Whilst compounds with R = OH, SH and NO2 show nematic phases, compound containing cyano substituent are smectogenic in nature.

Steglich esterification between 1-(4-hydroxyphenyl)-3-(pyridin-3-yl)prop-2-en-1-one and 4-dodecyloxybenzoic acid has produced a new compound, 4-[3-(pyridin-3-yl) prop-2-enoyl]phenyl 4-dodecyloxybenzoate. The title compound was characterized by IR and NMR analysis.

A new Schiff base ester, 3-hydroxy-4-[(phenylimino)methyl]phenyl 4-(hexadecanoyloxy)benzoate was synthesized and its IR, 1H-NMR, 13C-NMR and MS spectroscopic data are presented.

A new Schiff base ester, 4-{[(4-chlorophenyl)imino]methyl}-3-hydroxyphenyl 4-(hexadecanoyloxy)benzoate was synthesized and its IR, 1H-NMR, 13C-NMR and MS spectroscopic data are presented.

A new Schiff base ester, 4-{[(4-bromophenyl)imino]methyl}-3-hydroxyphenyl 4-(hexadecanoyloxy)benzoate was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are presented.

A new Schiff base ester, 4-{[(4-methoxyphenyl)imino]methyl}-3-hydroxyphenyl 4-(hexadecanoyloxy)benzoate was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are presented.

A new Schiff base, 4-{[(4-methylphenyl)imino]methyl}-3-hydroxyphenyl 4-(hexadecanoyloxy)benzoate was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are presented.

A new Schiff base ester, 4-({[4-(methylthio)phenyl]methylene}amino)phenyl dodecanoate was synthesized and its IR, 1H NMR, 13C NMR and EI-MS spectroscopic data are presented.

The asymmetric unit of the title complex, [Sn4(C4H9)8(C11H14NO2)4O2], consists of two crystallographically independent half-molecules. The other halves are generated by crystallographic inversion centers. In each tetranuclear molecule, both of the two independent Sn atoms are five-coordinated, with distorted trigonal–bipyramidal SnC2O3 geometries. One Sn atom is coordinated by two butyl groups, one O atom of the benzoate anion and two bridging O atoms, whereas the other Sn atom is coordinated by two butyl groups, two O atoms of the benzoate anions and a bridging O atom. All the butyl groups are equatorial with respect to the SnO3 trigonal plane. Weak intramolecular C—H...O hydrogen bonds stabilize the molecular structures. In one molecule, two of the butyl groups and the bridging benzoate anion are each disordered over two positions.

A new Schiff base ester, 4-{[(4-iodophenyl)imino]methyl}phenyl octadecanoate was synthesized and its IR, 1H NMR, 13C NMR and EI-MS spectroscopic data are presented.

In the title complex, [Sn(C6H5)3(C7H3ClNO4)(CH4O)], the five-coordinate SnIV atom exists in a trigonal–bipyramidal environment, formed by a monodentate carboxylate group, three phenyl rings and a methanol molecule. The axial sites are occupied by the O atoms of the methanol molecule and the carboxylate group, while the equatorial plane is formed by the C atoms of three phenyl rings. The benzene ring of the 2-chloro-4-nitrobenzoate ligand makes dihedral angles of 66.18 (7), 74.71 (7) and 77.39 (7)° with respect to the three phenyl rings. In the crystal, the molecules are linked via intermolecular O—H...O and C—H...O hydrogen bonds into a column along the b axis.

A new Schiff base ester, 4-{[(4-fluorophenyl)imino]methyl}-3-hydroxyphenyl 4-(hexadecanoyloxy)benzoate was synthesized and its IR, 1H NMR, 13C NMR and EI-MS spectroscopic data are presented.

The title complex, [Sn4(C4H9)8(C7H3ClNO4)4O2], is a cluster formed by a crystallographic inversion center around the central Sn2O2 ring. Both of the two independent Sn atoms are five-coordinated, with distorted trigonal–bipyramidal SnC2O3 geometries. One Sn atom is coordinated by two butyl groups, one O atom of the benzoate anion and two bridging O atoms, whereas the other Sn atom is coordinated by two butyl groups, two O atoms of the benzoate anions and a bridging O atom. The O atoms of the bridging benzoate anion are disordered over two sites with an occupancy ratio of 0.862 (12):0.138 (12). One of the butyl groups coordinated to the Sn2O2 ring is disordered over two sites with an occupancy ratio of 0.780 (8):0.220 (8), whereas both of the two butyl groups coordinated to the other Sn atom are disordered over two sites with occupancy ratios of 0.788 (5):0.212 (5) and 0.827 (10):0.173 (10). All the butyl groups are equatorial with respect to the SnO3 trigonal plane. In the crystal, complex molecules are stacked down [010] with weak intermolecular C—H...π interactions stabilizing the crystal structure.

A new Schiff base ester, 3-hydroxy-4-{[(4-methoxyphenyl)imino]methyl}phenyl octadecanoate, was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are presented.

A new Schiff base ester, 3-hydroxy-4-{[(4-chlorophenyl)imino]methyl}phenyl octadecanoate, was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are presented.

A new Schiff base ester, 3-hydroxy-4-{[(4-bromophenyl)imino]methyl}phenyl octadecanoate, was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are presented.

A new Schiff base ester, 3-hydroxy-4-{[(4-fluorophenyl)imino]methyl}phenyl octadecanoate, was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are presented.

A new Schiff base ester, 3-hydroxy-4-{[(4-ethylphenyl)imino]methyl}phenyl octadecanoate, was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are presented.

A new Schiff base ester 3-hydroxy-4-[(phenylimino)methyl]phenyl myristate was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are presented.

A new Schiff base ester, 4-{[(3-chlorophenyl)imino]methyl}-3-hydroxyphenyl myristate, was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are presented.

A heterocycle, 4-[(1,3-benzothiazol-2-ylimino)methyl]phenyl dodecanoate, was synthesized and its IR, 1H NMR, 13C NMR, elemental analysis and MS spectroscopic data are presented. This new compound exhibited smectic A phase.

A new heterocycle, 2-[4-(hexadecyloxy)-3-methoxyphenyl]-1,3-benzothiazole, was prepared and its IR, 1H NMR, 13C NMR, elemental analysis and MS spectroscopic data are reported.

A new Schiff base ester, 4-{[(3-cyanophenyl)imino]methyl}-3-hydroxyphenyl tetradecanoate, was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are presented.

A new Schiff base ester, 3-hydroxy-4-{[(3-nitrophenyl)imino]methyl}phenyl tetradecanoate, was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are presented.

A new heterocycle 2-(3-methoxy-4-hexadecanoyloxyphenyl)benzothiazole was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are presented.

2-(4-Heptyloxyphenyl)benzothiazole was synthesized and its IR, 1H NMR and MS spectroscopic data are presented.

A new 2-(4-propyloxyphenyl)benzothiazole was synthesized and its IR, 1H and 13C NMR and MS spectroscopic data are presented.

A new Schiff base ester comprising of heterocyclic moiety, 3-hydroxy-4-{[(6-methoxy-1,3-benzothiazol-2-yl)imino]methyl}phenyl palmitate was synthesized and its IR, 1H NMR, 13C NMR, elemental analysis and MS spectroscopic data are presented.

A new Schiff base ester, 4-[(4-dimethylaminobenzylidene)amino]phenyl tetradecanoate, was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are reported.

A new Schiff base 4-[(pyridin-3-ylmethylene)amino]phenyltetradecanoate was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are presented.

The ability of tetraethylenepentamine modified peanut husks (TEPA-PH) composite beads in the removal of an anionic azo dye, Congo Red (CR) was studied. In batch adsorption studies, various parameters such as contact time, initial dye concentration, pH, dosage and agitation rate were included to study their influence towards the adsorption process. The TEPA-PH composite beads formed were thoroughly characterized by using several techniques which includes Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy, Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). The experimental data followed the pseudo-second-order kinetic model with R² close to unity. Among the isotherm models, the experimental data is best fitted to Freundlich isotherm model by having R² of 0.9948. The maximum adsorption capacity was determined to be 19.5695 mg/g using the Langmuir model. The significant factors were selected using the Plackett-Burman (PB) design and the optimization of the adsorption model was done using the Response Surface Methodology (RSM). With optimum conditions of 180 min of contact time, 62.5 mg/L of initial dye concentration and 0.35 g of dosage, the percentage uptake of CR can reach 77.11%. [ABSTRACT FROM AUTHOR]

Structure-property relationship is one of the most important research areas in the liquid crystals. Therefore, in the present work, we studied a new series of rod-like heterocyclic liquid crystals, 6-methyl-2-[4-(4-alkoxybenzoyloxy)benzylideneamino]benzothiazoles. The rod-like molecules having heterocyclic and two phenyl rings as core system, imine and ester as linking units, long alkoxy chain at the terminal position. There are six members in the series with different length of alkoxy chain (CnH2n+1O-, where n = 6, 8, 10, 12, 14, 16). The structures of the compounds were elucidated using spectroscopic techniques. Their mesomorphic behaviours were determined by differential scanning calorimetry, polarizing optical microscopic and powder X-ray diffraction techniques. Members with shorter alkoxy chain (n = 6, 8, 10) exhibited single mesophase (nematic). As the alkoxy chain increased to n = 12, 14, 16, the nematic phase appeared together with an additional mesophase (smectic). The phase width was dependent on the alkoxy chain length. The incorporation of the methyl substituent at the sixth position (lateral) of the benzothiazole able to increase the clearing point and widen the mesophase width of the compounds. [ABSTRACT FROM AUTHOR]