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Preparative method for the synthesis of lithium, sodium, cesium, and calcium salts of ( E)-4-(5-arylisoxazol-3-yl)methyleneaminobutanoic, ( E)-6-(5-arylisoxazol-3-yl)methyleneaminohexanoic, ( E, S)-3-methyl-2-(5-arylisoxazol-3-yl)methyleneaminobutanoic, ( E, S)-4-methyl-2-(5-arylisoxazol-3-yl)methyleneaminopentanoic and ( E,2 S,3 S)-3-methyl-2-(5-arylisoxazol-3-yl)methyleneaminopentanoic acids was developed by reacting 5-phenyl(4-tolyl)isoxazole-3-carbaldehydes with amino acids like 4-aminobutyric and 6-aminocaproic acids, L-valine, L-leucine or L-isoleucine in the presence of lithium hydride, sodium methoxide, cesium carbonate or calcium hydride in boiling methanol. [ABSTRACT FROM AUTHOR]

o-Phenylenediamine reacts with 2-formyl-, 2-acetyl-, or 2-benzoylpyridine in ethanol in the presence of cobalt, nickel, copper, or zinc chlorides to form monomeric complexes MLCl· nHO {M = Co, Ni, Cu, Zn; L = N, N-bis(pyridin-2-ymethylidene)benzene-1,2-diamine, L = N, N-bis(pyridin-2-ylethylidene) benzene-1,2-diamine, L = N, N-bis[phenyl(pyridin-2-yl)methylidene]benzene-1,2-diamine; n = 0-3}. The condensation products (L-L) act in the complexes as tetradentate N,N,N,N-ligands. Thermolysis of the complexes occurs in two stages: dehydration (70-95°C) and complete degradation (320-450°C). At concentrations of 10-10 M, the complexes inhibit in vitro growth and proliferation of HL-60 human promyelocytic leukemia cells. [ABSTRACT FROM AUTHOR]

New zinc and cadmium complexes with 3-[2-( N-tosylaminobenzylidene)]aminoquinoline (HL) and 6-[2-( N-tosylaminobenzylidene)]aminoquinoline (HL) were synthesized. The structures of HL, HL and complexes ML (M = Zn, Cd) were established based on the elemental analysis data, IR spectroscopy, H NMR spectroscopy, and quantum chemical calculations. Electron absorption and photoluminescence spectra of the complexes were studied. OLED devices were developed, where ZnL complexes were used as an emission layer. This device emitted yellow light with CIE x = 0.436, y = 0.492 and x = 0.463, y = 0.484, maximum luminance at 10 V was 126 and 150 cd m, respectively. [ABSTRACT FROM AUTHOR]

The interaction of the conformational degrees of freedom of azomethines in the nematic phase, which is induced by electronic donor-acceptor properties of the terminal substituents of the benzylideneaniline core is studied. These degrees of freedom related to the rotation angles φ around the bonds between the substituent and the aniline ring (φ) and also between the CH=N bridge and the aniline ring (ω) are characterized by the parameters Q = 〈cosφ〉. It is found that the interaction of these degrees of freedom is manifested in the linear dependence Q( Q). Within the phenomenological theory the effect of this interaction on changes δ in the Q values during the nematic liquid crystal-isotropic liquid phase transition is revealed along with the temperature T and character of this transition. The derivation of previously established empirical dependences T( Q) is presented in the presence of direct and indirect steric effects of side substituents affecting the Q values. A diverse combination of δ signs in the nematic phase, which is a prerequisite for the conformational polymorphism of the nematic phases of azomethines, is shown. [ABSTRACT FROM AUTHOR]

A small library of new azomethine derivatives of 3-aryl-2-thioxo-2,3-dihydroquinazolin-4(1H)-ones was synthesized. The key intermediates 2-thioxo-quinazolinones (3a-e), obtained in 2 steps from the corresponding anilines, were treated with methyl chloroacetate to afford S-substituted esters (4a,d), which were then converted into corresponding acetohydrazides (5a,d). Further, acetohydrazide (5d) was converted to the azomethines derivatives (6a-k) by reacting with a number of suitably substituted benzaldehydes. FTIR, ¹H NMR, 13C NMR, GC-MS, and elemental analyses were used to confirm the assigned structures of the synthesized compounds. Further, compounds 3a, 5, and 6j were also confirmed by X-ray diffraction data. [ABSTRACT FROM AUTHOR]

Highlights: [•] We constructed three kinds of polymer devices with diimide-imines. [•] We analyze PV and ESI properties in the level of naphthalene diimide-imines structure. [•] We examine devices with various amounts of naphthalene diimide-imines. [•] PV effects depend on the device architecture and amount of compound in active layer. [ABSTRACT FROM AUTHOR]

The study is devoted to nucleophilic substitution of nitro groups in 1-amino-3,5-dinitropyrazole ( 1) and its amino group derived analogs. Compound 1 upon treatment with S-nucleophiles undergoes regioselective substitution of the nitro group at position 5. Azomethine 5 obtained by the condensation of 1 with benzaldehyde gives the nucleophilic substitution reaction with S-, O-and N-nucleophiles also with involvement of the nitro group at position 5. The synthesized 5-R-substituted azomethines 7-9 upon treatment with hydrazine hydrate form N-amino-5-R-3-nitropyrazoles and benzaldazine. [ABSTRACT FROM AUTHOR]

Highlights: [•] We analyze the influence of diimine structure on their photoluminescence properties. [•] Imine emitted blue, violet or green light in solution. [•] The theoretical electrochemical energy band gap of diimines was observed at in the range of 3.65–4.08eV. [•] Some of the diimines seems to be promising potential candidates for OLEDs. [ABSTRACT FROM AUTHOR]

Highlights: [•] We analyze the influence of imine structure on their physical properties. [•] Imines emitted blue, violet or green light in solution. [•] Electrochemical energy band gap of imines was observed at in range of 3.80–4.19eV. [•] Some of the imines seems to be promising potential candidates for optoelectronics. [ABSTRACT FROM AUTHOR]

Density, ultrasonic velocity and viscosity of azomethines containing sulfamethoxazole nucleus have been measured in N,N-dimethylformamide and tetrahydrofuran solutions over a wide concentration range at temperature 308.15 K. From these experimental data, acoustical parameters such as intermolecular free path length, isentropic compressibility and relaxation strength have been evaluated, that help understanding the molecular interactions occurring in these solutions. Furthermore, compressibility solvation number, the apparent molar compressibility and apparent molar volume of the solutions have been determined and discussed. [ABSTRACT FROM AUTHOR]

The reaction of cyano(2-isopropyltetrahydropyran-4-ylidene)acetic acid ethyl ester and 4-fluorophenylmagnesium bromide produced the cyanoester that was decarboxylated to the corresponding nitrile. Reduction of the latter by LiAlH formed 2-[4-(4-fluorophenyl)-2-isopropyltetrahydropyran-4-yl]ethylamine, reaction of which with aromatic aldehydes synthesized azomethines that were then reduced by NaBH to secondary amines. The last were transformed to oxalates and acetamides. It was shown that the secondary amine oxalates possessed high antibacterial activity. [ABSTRACT FROM AUTHOR]

The title compound, C16H12N4S, forms a three-dimensional layered network structure via intermolecular hydrogen bonding and π-stacking. The azomethine molecule adopts the thermodynamically stable E regioisomer and the pyridine substituents are antiperiplanar. The mean planes of the pyridine rings and the azomethine group to which they are connected are twisted by 27.27 (5) and 33.60 (5)°. The electrochemical energy gap of 2.3 eV based on the HOMO-LUMO energy difference is in agreement with the spectroscopically derived value. [ABSTRACT FROM AUTHOR]

Abstract: Schiff bases or azomethines are among the most important groups of biomolecules. These compounds have been found to reveal both remarkable biological activities and a variety of valuable practical applications. An interest in the exploration of novel series of synthetic Schiff bases has undoubtedly been growing due to their proven utility as attractive lead structures for the design of novel cytotoxic and cytostatic agents with a mechanism of action that sometimes differs from that of clinically authorized anticancer agents. Therefore, in the present paper we have focussed our attention on the collected synthetic simple Schiff bases of aldimine- and ketimine-types revealing anticancer activities in vitro, that have been described in the scientific literature during the last decade, and on structural variations whose affect the antiproliferative activity in sets of the designed molecules. [Copyright &y& Elsevier]

Three new azomethines based on triphenylamine with two or three substituents were obtained. Chemical structure and purity were confirmed by 1 H NMR, FTIR elemental analysis and mass spectroscopy. The investigations were focused on the relationship between chemical structure and properties important for optoelectronic materials. Thus, the studies of thermal, optical and electrochemical properties were carried out based on differential scanning calorimetry, thermogravimetric analysis, electronic absorption, photoluminescence and cyclic voltammetry measurements. The ongoing consideration of experimental results was complemented by theoretical calculations using the density functional theory method. The donor activity of obtained compounds was tested in bulk-heterojuntion photovoltaic cells with structure ITO/PEDOT:PSS/imine:PCBM/Al and ITO/PEDOT:PSS/imine:P3HT:PCBM/Al). The effect of the presence of the amino-thiophene-3,4-dicarboxylic acid diethyl ester groups and various number of hexyloxyphenyl units on imines properties was demonstrated.

This account gives an overview of our recent work in the area of conjugated azomethines derived from 2-aminothiophenes. It will be presented that mild reaction conditions can be used to selectively prepare symmetric and unsymmetric conjugated azomethines. It further will be demonstrated that azomethines consisting of various 5-membered aryl heterocycles lead to chemically, reductively, hydrolytically, and oxidatively robust compounds. The optical and electrochemical properties of these materials can be tuned contingent on the degree of conjugation, type of aryl heterocycle, and by including various electronic groups. The end result is materials having colors spanning 250 nm across the visible spectrum. These colors further can be tuned via electrochemical or chemical doping. The resulting doped states have high color contrasts from their corresponding neutral states. The collective opto-electronic properties and the means to readily tune them, make thiophenoazomethine derivatives interesting materials for potential use in a gamut of applications. [ABSTRACT FROM AUTHOR]

New derivatives of the benzo[de]isoquinoline-1,3-dione system containing an amino group were synthesized by the reaction of 2-benzyl-6-bromobenzo[de]isoquinoline-1,3-dione with ethylenediamine and hydrazine. Further functionalization of the free amino groups leads to imines, amines, thioureas, and hydrazones. Some compounds exhibit high chemosensor selectivity in the determination of anions. [ABSTRACT FROM AUTHOR]

Abstract: Optical (UV–vis and photoluminescence) properties of two soluble organic molecules based on azomethines with benzothiazole core (BTA1 and BTA2) were reported. The structures of both compounds are characterized by means FTIR, 1H NMR, and 13C NMR spectroscopy and elemental analysis; the results show an agreement with the proposed structure. The investigated compounds emitted blue light. Influence of excitation wavelength and concentration on maximum and intensity of emission of BTA1 and BTA2 was found. Electrochemical properties of the compounds were studied by differential pulse voltammetry. Introduction of fluorine moieties (BTA1) resulted in lower energy band gap (Eg ) of approximately ∼0.5eV, whereas BTA2 showed Eg of ∼2.8eV. The devices comprised of BTA1 with P3HT:PCBM (1:1:1) showed an open circuit voltage (V OC) of 0.40V, a short circuit current (J SC) of 1.19mA/cm2, and a fill factor (FF) of 0.23, giving a power-conversion efficiency (PCE) of 0.10% under AM1.5G irradiation (100mW/cm2). [Copyright &y& Elsevier]

128 Azomethines were synthesized through condensation of carbonyl compounds with various amines in pyridine in the presence of MeSiCl as promoter and water scavenger in 58-98 % yield. EtN was added to reaction mixtures before precipitating the product with HO to prevent acid catalyzed hydrolysis of the C=N bond. The scope and limitation of the method are discussed. High yields and simple setup/workup procedure make this method suitable for the combinatorial synthesis of azomethines, which are suitable as starting materials for high throughput synthesis of various combinatorial libraries. The azomethines synthesized were used as starting materials in a one-pot combinatorial synthesis of amines and amides. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Thermal properties of two azomethine liquid crystals with a benzothiazole core were synthesized and investigated by applied Mettler-Toledo AG equipment (TG/DSC). Azomethines with benzothiazole core was obtained by nucleophilic addition of benzothiazole-2-carboxaldehyde in N, N-dimethylacetamide (DMA) solution with 4-(heptadecafluoroctyl)aniline (BTA1) or 4-hexadecylaniline (BTA2). The differential scanning calorimetry (DSC) was employed to evaluate their phase transitional behavior. Variable heating and cooling rates were used to study liquid crystalline properties of azomethines with benzothiazole core. Compound BTA1 exhibited liquid crystalline properties, while BTA2 is non-mesogenic. Three or four endothermic DSC peaks were observed for both compounds during heating process with the rate 0.5 °C/min. The mesophase was identified and confirmed by XRD study and polarized optical microscopy (POM) too. The thermal stability was determined by thermogravimetric analysis (TG). The temperatures of 5% mass loss ( T) of BTA1 and BTA2 range from 212 to 317 °C in nitrogen. [ABSTRACT FROM AUTHOR]

Mono- and bis-chelate iron(III)-containing complexes with a tridentate azomethine ligand based on n-dodecyloxybenzoic acid ester derivatives with oxybenzoyl-4-salidene-N′-ethyl-N-ethylenediamine with NO counterions are obtained. The structure of the compounds is determined by IR spectroscopy, elemental analysis, and mass spectrometry (MALDI-ToF MS). It is found that the complexation of iron salts with tridentate ligands in a mixture of solvents (alcohol:benzene) results in the formation of bischelate compounds of the composition 1:2 with octahedral packing of iron in the complex, while in pure alcohol solutions, asymmetric mono-chelate complexes are obtained. [ABSTRACT FROM AUTHOR]

A new and efficient method has been developed for the synthesis of biologically significant 2-arylbenzimidazoles, 2-arylbenzothiazoles, and azomethines using recyclable and inexpensive polyvinyl pyrrolidone (PVP)–stabilized Ni nanoparticles in ethylene glycol at room temperature in excellent yields. [ABSTRACT FROM AUTHOR]

Abstract: The tetradentate azomethines were prepared by condensation of 2-piperazin-1-ylethanamine, (3-morpholin-4-ylpropyl)amine with 3-methylthophene-2-carbaldehyde, salicylaldehyde and 1H-imidazole-5-carbaldehyde. The ligands were characterized based on mass, 1H and 13C NMR, FTIR, and elemental analyses. New complexes of ligands with copper(II), iron(II) and nickel(II) were synthesized. Metal complexes are reported and characterized by magnetic, conductivity measurements, FTIR, elemental and thermal analyses (TG–DTA). Spectral analyses show that all the ligands behave as neutral tetradentate ligands and bind to the metal via azomethine N, piperazine N, salicylaldehyde O, morpholine O, imidazole N and thiophene S. Results of magnetic measurements and thermal studies show that the geometrical structures of the nickel(II) complexes are square planar while copper(II) and iron(II) are octahedral. The thermal behaviors of these complexes show that the hydrated complexes lose the hydration water molecule in the first step, followed immediately by decomposition of the anion and ligand molecules in subsequent steps. The solvatochromic behavior of the iron(II)–L2 complex was investigated using the electronic spectra of 1×10−3 M in four different solvents. The solvatochromism was explained in terms of MLCT transition and solvent characteristics such as polarity, nature and acceptor–donor properties. [Copyright &y& Elsevier]

In this work we have studied the dielectric properties of five unsymmetrical azomethine (A1−A5) liquid crystals prepared from different aldehydes or obtained from various amines. The effects of rod length and type of terminal chains on the thermal and mesomorphic behaviours were investigated by dielectric spectroscopy. The wide frequency range dielectric spectroscopy confirmed the phase transition detected in an earlier study. Moreover, a relaxation behaviour was detected in three compounds in various phases, which was connected to a particular dipolar group present in these materials, in contrast to two other compounds having a similar molecular structure but lacking strong dipolar groups. The relaxation processes changed their character or disappeared during the phase transition. [ABSTRACT FROM AUTHOR]

Abstract: The molecules bearing triphenylamine (TPA) structure were widely investigated mainly as active hole-transporting materials for construction of light-emitting diodes. Our previous research was concerned for poly(azomethines) bearing TPA in structure. Now we present research of its model compounds. A series of five conjugated azomethines have been synthesized in reaction of different aromatic diamines and 4-formyltriphenylamine. The structures of given azomethines were characterized by means of FTIR, 1H NMR, and 13C NMR spectroscopy and elemental analysis. Optical, electrochemical and thermal properties of all compounds were investigated by means of differential scanning calorimetry (DSC), UV–vis spectroscopy, photoluminescence spectroscopy and cycling voltammetry. Influence of chemical structure of the compounds on their properties has been analyzed. [Copyright &y& Elsevier]

Abstract: New, solution processable azomethines, consisting of electron-donating triarylamine units (TPA) were synthesised via condensation of 4-formyltriphenylamine with 1,5-diaminonaphthalene, 1,4-diaminonaphthalene, 3,3′-dimethylnaphtidine and 3,8-diamino-6-phenylphenanthridine in view of their potential application in organic (opto)electronics. The structures of the compounds were characterized by means of IR, NMR spectroscopy and elemental analysis; the results show an agreement with the proposed structure. The prepared azomethines exhibited glass-forming properties with glass-transition temperatures in the range of 102–222°C. Optical properties of the prepared compounds were investigated by UV–Vis and photoluminescence (PL) measurements. The obtained compounds emitted blue–green light in chloroform solution with emission maximum (λ em) at ca. 500nm and blue one (λ em ∼440nm) in blend with PMMA. The electrochemical behavior of azomethines was studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The HOMO level was in the range from −5.08 to −5.22eV. The HOMO, LUMO levels and energy band gap (E g) were additionally calculated theoretically at B3LYP/6-31G(d,p) level. It was found that imine obtained from 1,4-diaminonaphthalene exhibited better conjugation than other TPA-based azomethines. Preliminary electrical conductivity measurements were carried out on ITO/compound/Al devices. [Copyright &y& Elsevier]

Abstract: New arylene bisimide derivatives, both low molecular compounds and polymers consisting of a naphthalene diimide core and imine linkages were synthesized. The azomethine-diimides were prepared from N,N′-bis(4-amino-2,3,5,6-tetramethylphenyl)naphthalene-1,4,5,8-dicarboximide (DANDI) which was condensed with 4-pyridinecarboxaldehyde or 1,3-benzothiazole-2-carboxaldehyde or 2-thiophenecarboxaldehyde or 2,2′-bithiophene-5-carboxaldehyde. Poly(azomethine-naphthaleneimide)s were obtained by high temperature polycondensation of DANDI with 2,5-thiophenedicarboxaldehyde or 2,2′-bithiophene-5,5′-dicarboxaldehyde. The materials do not show decomposition below 300°C. The azomethine-diimides exhibited glass-forming properties with glass transition temperatures in the range of 80–195°C. For the first time, to the best of our knowledge, amorphous molecular naphthalene diimide compounds were obtained. Optical properties of the prepared compounds were investigated by UV–vis and photoluminescence (PL) measurements. Most of the azomethine-diimides emitted green light with the highest intensity with emission maximum (λ em) at ca. 519–535nm contrary to polymers which λ em was at 450 and 485nm. All the compounds are electrochemically active and azomethine-diimides undergo quasi-reversible reduction and irreversible oxidation as evidenced by cyclic voltammetry (CV). In all studied molecules the electrochemically determined HOMO level is in the range of −5.5 to −5.13eV whereas the LUMO level is close to −4.0eV for azomethine-diimides and −3.8eV for polymers as determined by differential pulse voltammetry (DPV). The investigated compounds exhibited low electrochemical band gap (1.21–1.5eV) being promising for optoelectronic applications. [Copyright &y& Elsevier]

From 3-allyl salicylaldehyde and 4-aminoazobenzene (HL), the Schiff-base complex of copper(II) is synthesized and structurally characterized. The crystallographic unit of a CuL ( 1) single crystal contains two independent molecules of the complex. Coordination polyhedra of copper atoms are slightly distorted squares; azomethine ligands are in the trans-position. The neighboring molecules of the complex are bonded by intermolecular π stacking interactions. [ABSTRACT FROM AUTHOR]

1-(Anthracen-9-ylmethyl)-1 H-benzimidazol-2-amine was synthesized by alkylation of benzimidazol-2-amine with 9-chloromethylanthracene, and a series of azomethines based on it was obtained. Spectral investigations of the 9-anthrylmethylbenzimidazole derivatives revealed their high chemosensor activity with respect to hydrogen cations. Quantum-chemical investigation of the structures obtained showed that they possess high proton affinity and can be regarded as analogs of 'proton sponges'. [ABSTRACT FROM AUTHOR]

Abstract: A new thermotropic liquid crystals containing azobenzene unit and imine linkages were synthesized via condensation of 4-(4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,11-heptadecafluoroundecyloxy)benzaldehyde with 4-aminoazobenzene (AzoAz-1) and 4,4′-diaminoazobenzene (AzoAz-2). The structures of compounds were characterized by means of NMR, FTIR spectroscopy and elemental analysis; the results show an agreement with the proposed structure. The mesomorphic behavior of the unsymmetrical AzoAz-1 and symmetrical AzoAz-2 azobenzeneimines was investigated via differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). Based on the POM and DSC measurements AzoAz-1 exhibited smectic phases (SmX, SmA), while AzoAz-2 showed smectic (SmX1, SmX2, SmA) and nematic (N) mesophases. Optical properties of the azobenzeneimines were tested by UV–vis and photoluminescence (PL) spectroscopy in various solvents. Preliminary investigations of electrical properties of the new compounds were carried out by current–voltage (I–V) measurements performed on ITO/compound/Al device. [Copyright &y& Elsevier]

Abstract: Two novel poly(azomethinenaphthaleneimide)s (poly(AZ-NI)s) and azomethine-naphthalene diimide (AZ-NI) consisting of electron-donating triarylamine with imine linkages and electron-accepting naphthalene diimide moieties were prepared via condensation of N,N′-bis(4-amino-2,3,5,6-tetramethylphenyl)naphthalene-1,4,5,8-dicarboxyimide (DANDI) with 4-formyltriphenylamine, 4,4′-diformyltriphenylamine and 4,4′,4″-triformyltriphenylamine. The thermal degradation kinetics of obtained compounds was studied by TGA. The activation energy (E a ) of thermal decomposition process was estimated by the first order Coats–Redfern equation and was in the range 115.1–266.7kJ/mol. Poly(AZ-NI)s and AZ-NI exhibited useful levels of thermal stability, their 5% weight-loss temperatures were above 350°C. Optical properties of the prepared compounds were investigated by UV–vis and photoluminescence (PL) measurements. The obtained alternating donor–acceptor compounds emitted mainly blue light. The electrochemical behavior of poly(AZ-NI)s, AZ-NI and DANDI was studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). As calculated from CV, the electrochemical energy band gap (E g) of the linear polymer was equal to 1.15eV, but the E g of the branched one was lower: 1.06eV, whereas the E g of AZ-NI and DANDI was 1.32 and 0.47eV, respectively. For the first time, to the best of our knowledge, polynaphthaleneimides with triphenylamine units and azomethine linkages have been described in this article. [Copyright &y& Elsevier]

A series of mono and bis 2-2-(arylidineaminophenyl)indole azomethines have been synthesized by a condensation reaction of 2-(2-amino phenyl) indole with various mono and diketones R-CO-R /R-CO-X-CO-R (1:1/2:1 ratio) in ethanol media. The synthesized azomethines were characterized via IR, H-NMR, C-NMR, MS and elemental analysis. The antimicrobial activity of these compounds against different bacteria and fungi was also evaluated. [ABSTRACT FROM AUTHOR]

Some new azomethines have been synthesized from vanillin and their characterization was done by IR, 1H NMR and mass spectra. Further, some physicochemical properties such as density and refractive index have been studied for these synthesized compounds in different solvents at 308.15 K. The heat of the solution was also determined at different temperatures. [ABSTRACT FROM AUTHOR]

Abstract: The thermal and opto-electrical properties of new thermotropic compounds based on tetraphenylphthalic-based imides have been explored. Energy band gap () was calculated from absorption spectrum and absorption coefficient α. Current–voltage (I–V) measurements were performed on ITO/compound/Al, ITO/compound:PCBM/Al and ITO/PEDOT:PSS/compound:PCBM/Al devices before and after irradiation with light (under illumination 1000W/m2). Compounds were blended with [6,6]-phenyl C61 butyric acid methyl ester (PCBM) in the weight ratio 1:1 and additionally tested using various AFM techniques. The mesogenic properties were characterized by POM and DSC. Both compounds exhibited liquid crystalline properties. Preliminary photovoltaic experiments were carried out for two kinds of bulk heterojunction devices (BHJ) and compared with reference device. For the first time, to the best our knowledge, tetraphenylphthalic-based imides with liquid crystalline properties were examined and described in the article. [Copyright &y& Elsevier]

Quantum chemical calculations are applied to study the structure and energy of the complexes of a series of Schiff bases (SBs) with acetic acid. The results of the calculations give evidence that a weak hydrogen bond occurs between the oxygen atoms of the acid and SB aromatic protons in these complexes along with the CHCOOH...N=CH H-bond. The structure of the complexes is confirmed experimentally by measuring the nuclear Overhauser effect. The effect of the properties of SB terminal substituents on the stability of SB-acid complexes is analyzed. [ABSTRACT FROM AUTHOR]

Two series of novel symmetrical azomethines prepared by the condensation of 4,4'-(butane-1,4-diylbis(oxy))bis(butane-4,1-diyl)bis(4-aminobenzoate) (PBBA470) and 5,10,15,20,25,30,35,40,45,50,55,60-dodecaoxatetrahexacontane-1,64-diylbis(4-aminobenzoate) (PBBA 1200) with a range of aldehydes have been characterised by 1H and 13C nuclear magnetic resonance, Fourier transform infrared and UV-Vis spectroscopy. Current-voltage measurements were performed using a device comprising indium-tin oxide/compound/Alq3/Al. The effect of rod length and the nature of the terminal chains on the thermal and mesomorphic behaviour of these materials were investigated by differential scanning calorimetry, polarising optical microscopy and wide- and small-angle X-ray diffraction. Additionally, the compounds were studied using various atomic force microscopy techniques, including mode and phase imaging, and measurements based on local contrast force-distance curves and roughness, together with skew and kurtosis, are presented. [ABSTRACT FROM AUTHOR]

An efficient, clean, cheap, and quick procedure for the condensation of aromatic primary amine, namely, 4-aminophenazone, with different aryl carbonyls to produce azomethines under solvent-free and catalyst-free conditions at room temperature has been described. Their structures were confirmed by 1H-nuclear magnetic resonance (NMR), infrared (IR), mass spectra, and elemental analysis. The corresponding azomethines has been screened virtually using bioinformatical parameters on the basis of hypothetical antibacterial pharmacophore structure designed to interact with both of gram-positive bacteria and gram-negative bacteria. The virtually screened molecules were subjected to screening against certain strains of gram-positive and gram-negative bacteria. Based on the results of initial screening, the bactericidal action of some selected compounds has been increased by hybrid coupling with silver nanoparticles. The results thus obtained are discussed. [ABSTRACT FROM AUTHOR]

Abstract: The optical, electrical and thermal properties of unsymmetrical imine with two fluorinated chains are described. The structure of imine was characterized by means of 1H, 13C NMR spectroscopy and elemental analyses and the results show an agreement with the proposed structure. The wide-angle X-ray diffraction [WAXD(T)] technique in different temperatures was used to probe the structural properties of the azomethine. Mesomorphic behaviour was investigated via differential scanning calorimetry (DSC) and polarizing optical microscopy (POM) studies. Additionally, the mesomorphic behaviour of the azomethine presented in this work was compared with other azomethines. The absorption (UV-vis), photoluminescence (PL) and thermoluminescence (TL) features of the compound are documented. The sample was irradiated with a test dose of 2Gy Co-60 gamma rays. Current–voltage (I–V) measurements were performed on an ITO/Az/Al device in the dark and during irradiation with light (under illumination of 1000W/m2). [ABSTRACT FROM AUTHOR]

Abstract: A new type of thermotropic liquid crystalline compounds containing azomethine linkages and naphthalene diimide moieties were synthesized via condensation of novel N,N′-bis(4-amino-2,3,5,6-tetramethylphenyl)naphthalene-1,4,5,8-dicarboximide with 4-(4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,11-heptadecafluoroundecyloxy)benzaldehyde and 4-octadecyloxybenzaldehyde. The structures of compounds are characterized by means of FTIR, NMR spectroscopy and elemental analysis; the results show an agreement with the proposed structure. Optical properties of the obtained azomethine–naphthalene diimides (AZ-NIs) in solution and in solid state as thin films on the quartz substrate were tested by UV–vis spectroscopy. The electrochemical behavior of AZ-NIs was studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energy levels, and electrochemical () and optical (E g) band gap values were calculated using the results of electrochemical and UV/vis measurements, respectively. The electrical properties of the azomethine–naphthalene diimides were investigated by current–voltage (I–V) measurements. I–V characteristics were performed on ITO/compound/Al, and ITO/compound:PC61BM/Al devices in the dark and during irradiation with light (under illumination 1000W/m2). Additionally, the azomethine–naphthalene diimides films were tested using AFM technique. The mesomorphic behavior of the AZ-NIs was investigated via differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). First time, to the best of our knowledge, compounds with both azomethine and naphthalene diimide units with liquid crystalline properties were described in this article. [ABSTRACT FROM AUTHOR]

zomethine complexes of copper, nickel, cobalt, and zinc are demonstrated to favor selective transfer in the medium of polyorganosiloxanes. In studies of the friction surfaces with the use of methods of optical and scanning electron microscopy, energy-dispersion electron probe X-ray microanalysis, and infrared frustrated total internal reflection spectroscopy, the formation of a transition-metal and tribopolymer film containing polyorganosiloxane fragments is found. [ABSTRACT FROM AUTHOR]

Abstract: Three discotic-shaped azomethines were prepared by condensation reactions of 4,4′,4″-triformyltriphenylamine with various aliphatic monoamines. Their chemical structures were confirmed by FTIR, 1H, 13C NMR spectroscopies, as well as elemental analysis. Thermal properties of the azomethines were examined by differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and X-ray diffraction (WAXRD, SAXRD). Moreover, UV–vis properties of the thin films of the compounds were investigated on the quartz substrate without and with [6,6]-phenyl C61 butyric acid methyl ester (PC61BM). Current–voltage (I–V) measurements were performed on ITO/compound/Al, ITO/compound:PC61BM/Al and ITO/PEDOT:PSS/compound:PC61BM/Al devices in the dark and during irradiation with light (under illumination 1000W/m2). Additionally, the compounds were tested using various AFM techniques. [ABSTRACT FROM AUTHOR]

The condensation of ethyl 2-[(2-aminophenyl)aminomethylidene]-3-oxo-3-polyfluoroalkyl-propionates with aldehydes (salicylaldehyde, furfural, and benzaldehyde) affords the corresponding azomethine derivatives exhibiting the complexing ability toward copper and nickel ions. [ABSTRACT FROM AUTHOR]

The synthesis and thermal properties of unsymmetrical imine with a fluorinated chain and a carboxylic group are described. The mesomorphic behavior was investigated via differential scanning calorimetry (DSC) and polarizing optical microscopy (POM) studies. Additionally, we compared the mesomorphic behavior of the azomethine presented in this work with other azomethines. [ABSTRACT FROM AUTHOR]

The synthesis and mesomorphic properties of a series of thermotropic liquid crystalline symmetrical rod and bent-shaped imines containing two long alkoxysemifluorinated chains were reported. Three different diamines varying in the number of phenylene rings from 1 to 3 were used to understand structure-mesomorphic property correlation. Differential scanning calorimetry, X-ray diffraction and polarised optical microscopy were used to determine their phase transition behaviour. An enantiotropic smectic phase was observed for all the systems studied. The thermal properties of the azomethines were discussed in relation to the core shape and length of the core. Current-voltage measurements were performed on ITO/compound/Alq3/Al and ITO/TiO2/compound/Alq3/Al devices before and after irradiation with light (about 1000 W m-2). To prepare the TiO2 layer, the sol-gel technique was applied. [ABSTRACT FROM AUTHOR]

A new series of thermotropic phosphorus-based liquid crystalline (LC) dendrimers based on a thiophosphoryl-phenoxymethyl(methylhydrazono) core (thiophosphoryl-PMMH) up to the fifth generation has been synthesised by solution condensation of aldehyde groups, surface-functionalised thiophosphoryl-PMMH dendritic substrates of generation numbers G0.5 to G5.5, with the appropriate molar equivalents of the pro-mesogenic n-hexadecylaniline mono-functional building block. Their chemical composition has been confirmed by 1H/13C/31P nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, elemental analysis. Optical properties have been studied by ultraviolet-visible absorption, photoluminescence spectroscopy and polarised optical microscopy, and thermal characteristics by differential scanning calorimetry. Electrical studies have been made using the current-voltage characteristics of organic light-emitting diodes consisting of multi-layered indium tin oxide/dendrimer/aluminium tris(8-hydroxyquinoline)Al architecture. It has been demonstrated that the molecular engineering approach adopted can successfully lead to phosphorus-containing dendritic organic semiconductors (OSCs) which show tunable mesomorphic behaviour (extension of the observed smectic mesophase) and (opto) electronic properties, owing to their peripheral decoration with a tunable number of azomethine-based optically active chromophoric units. This rare combination of 'tunable by design' properties makes this series of thermostable thiophosphoryl-PMMH-based LC dendrimers a particularly appealing class of OSCs for use in optically and/or electronically active layers of (opto)electronic devices such as light-emitting diodes, field-effect transistors, solar cells and lasers. [ABSTRACT FROM AUTHOR]

3,3'-Diacetyloxy (2), 3,3'-dihydroxy (3), 4,4'-diamino (4), and 4-amino (5) diphenylselenide derivatives were prepared as new precursors for the title studies. Compound 6 was obtained by condensation of 4 with an appropriate aromatic aldehyde. Unsymmetrical diphenylselenides 7 and 8 were obtained by condensation of 4 and/or 5 with an aromatic aldehyde. Compound 7 undergoes facile condensation with the same aldehyde present in its arylidene moiety to yield 6, while condensation with another different aromatic aldehyde yielded unsymmetrical 4-arylideneamino diphenylselenide derivative 9. Oxidation of 6, 8, and 9 using lead tetra acetate and/or N-bromosuccinimide yielded symmetrical bis-(2-aryl benzoxazol-6-yl) (10), unsymmetrical 3'-hydroxy, 2-aryl benzoxazol-6-yl selenides (11), and 2-aryl benzoxazol-6-yl, 2'-aryl' benzoxazol-6'-yl selenide derivatives (12), respectively. Compound 10 was prepared in one-pot unequivocal synthesis by fusion of 4 with the appropriate aromatic aldehyde, while 12 was prepared by fusion of 4 with two different aromatic aldehydes. In certain cases, 6 and 9 were heated on a direct flame until complete homogeneity afforded the corresponding 10 and 12. The structures of the synthesized compounds are based on physical data, IR, 1H NMR, 13C NMR, chemical means, and mass spectral data. Some of the synthesized compounds were biologically tested. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. [ABSTRACT FROM AUTHOR]