Photoelectric properties of the charge-transfer complex of polyvinylcarbazole with tetracyanoquinodimethane

Photoelectric properties of a polymeric PVK-TCNQ charge transfer complex have been investigated as a function of component weight ratio, wavelength and intensity of light, temperature and voltage; the investigation also covered the kinetics of photoconductivity. The results have been interpreted using Poole-Frenkel's theory and Onsager's theory of recombination.     

Semiconducting polymers based on charge-transfer complexes. IV. Electrical properties and structure of polymeric charge-transfer complexes

Model electron donor molecules, 10-methylphenothiazine and 4-(methylthio)anisole, and polymeric electron donors which contained these molecules on the side chains of N-acyl-substituted polyethylenimines, were complexed with the electron acceptors, dichlorodicyanoquinone (DDQ), tetracyanoquinodimethane (TCNQ), tetracyanoethylene (TCNE), and tetranitrofluorenone (TNF). The model donors formed 1:1 complexes with all the acceptors except TCNE. The polymeric donors formed amorphous complexes with DDQ, TCNQ, and TCNE. Crystalline complexes were formed with TNF which had low melting points (lower than the model complexes and the pure polymer). This is apparently due to poor lateral packing of the polymer chains. Electrical resistivities were lower for all the polymer complexes than for the corresponding model complexes. Electrical resistivity also decreased with increase in complex crystallinity. In the best case the polymer complex was two hundred times as conducting as the model. The concentration of unpaired electrons measured by EPR was nearly independent of temperature. Most of the electrons seen are trapped and do not participate in conduction. Thermal activation energies for conduction were in the range of 0.5–1.8 eV and were nearly equal for the model and corresponding polymeric complexes. Elongation of polymer complex with TCNQ by rolling produces a decrease in resistivity in the roll direction, although the complex is amorphous. This reinforces the hypothesis that conduction is parallel to the polymer backbone. A polymer–tetranitrofluorenone complex was photoconducting, though the photoconductivity was smaller than the dark conductivity at the level of illumination used. Dember and Seebeck effects indicated that the major carrier in the complex was holes.     

Spectrophotometric analysis of selective serotonin reuptake inhibitors based on formation of charge-transfer complexes with tetracyanoquinodimethane and chloranilic acid

A simple, accurate, and sensitive spectrophotometric method for analysis of selective serotonin reuptake inhibitors (SSRIs) has been developed and validated. The analysis was based on the formation of colored charge-transfer complexes between the intact molecule of SSRI drug as an n-electron donor and each of tetracyanoquinodimethane (TCNQ) or p-chloranilic acid (pCA) as electron acceptors. The formed complexes were measured spectrophotometrically at 842 and 520 nm for TCNQ and pCA, respectively. Different variables and parameters affecting the reactions were studied and optimized. Under the optimum reaction conditions, linear relationships with good correlation coefficients (0.9975-0.9996) were found between the absorbances and the concentrations of the investigated drugs in the concentration ranges of 4-50 and 20-400 microg/mL with TCNQ and pCA, respectively. With all the investigated drugs, TCNQ gave more sensitive assays than pCA; the limits of assay detection were 2.5-4.8 and 20-40 microg/mL with TCNQ and pCA, respectively. The intra- and interassay precisions were satisfactory; the relative standard deviations did not exceed 2%. The proposed procedures were successfully applied to the analysis of the studied drugs in pure form and pharmaceutical formulations with good accuracy; the recovery values were 98.4-102.8 +/- 1.24-1.81%. The results obtained from the proposed method were statistically comparable with those obtained from the previously reported methods.     

Synthesis and characterization of two charge-transfer salts based on Keggin-type polyoxometalates and morpholinebiguanide

Two new inorganic-organic salts, formulated as (C₆H₁₃N₅OH)₂ [HPMo₁₂O₄₀] · 5H₂O and (C₆H₁₃N₅OH)₃[PW₁₂O₄₀], were synthesized and characterized by elemental analysis, IR, ESR, diffuse reflectance spectra, thermogravimetry, and X-ray photoelectron spectroscopy. Solid diffuse reflectance spectra showed charge-transfer interactions between the inorganic and organic moieties in the solid state. Salt I had strong photosensitivity for UV light or X-ray irradiation, and its photochromic reaction under UV light was found to exhibit first-order kinetics. The article is published in the original.     

Reaction of 2-arylazobenzimidazolium quaternary salts with amines

Different behaviors of aromatic and nonaromatic amines with respect to a change in the structure of the salt and variations in the reaction conditions were revealed in a study of the reaction of 2-arylazobenzimidazolium quaternary salts with amines. Aliphatic and secondary cyclic amines react at comparable rates via pathways involving cleavage of the azo group and replacement of the hydrogen in the para position relative to the azo group. The reaction with aromatic amines proceeds primarily via the amination pathway, and a methyl group in the meta position relative to the azo group facilitates replacement of the hydrogen atom significantly.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 817–824, June, 1982.     

Synthesis of lepidine and its derivatives from aromatic amines and quaternary salts of Mannich bases

A quaternary salt of 4-(diethylamino)butan-2-one, methyldiethyl-3-ketobutylammonium methyl sulfate, is used as an alkylating agent to synthesize lepidine and 1-phenyllepidine salts. The method gives good yields, under mild conditions, of lepidine and 1-phenyllepidine perchlorate. An intermediate product is isolated, and a reaction mechanism suggested.     

Synthesis and properties of catechol-fused tetrathiafulvalene derivatives and their hydrogen-bonded conductive charge-transfer salts

Catechol-fused tetrathiafulvalene (TTF) derivatives have been designed and synthesized as a new type of π-electron donor molecules having two phenolic hydroxyl groups. Cyclic voltammetry measurements and quantum chemical calculations demonstrated the electronic effect of the direct fusion of the catechol unit to the TTF π-skeleton. In the charge-transfer (CT) salts with bromide or chloride anions, a one-dimensional hydrogen-bonded chain was formed by the intermolecular OH?X network between the catechol moieties and the halide anions. The slight dissimilarity of the hydrogen-bond distances for the two CT salts gave rise to the significant differences in their overall molecular arrangements and intermolecular interactions as well as the electrical resistivities.     

Hydrogen-bonded networks in organic conductors: crystal structures and electronic properties of charge-transfer salts of tetracyanoquinodimethane with 4,4'-biimidazolium having multiprotonated States

[structure: see text] Novel hydrogen-bonded charge-transfer salts of TCNQ with mono- and diprotonated 4,4'-biimidazolium were synthesized in order to demonstrate the high potential of the 4,4'-biimidazole system in a molecular conductor from the viewpoint of crystal engineering and electronic modulation. Crystal structure analyses of neutral 4,4'-biimidazole and TCNQ salts revealed the formation of two types of hydrogen-bonding modes of the 4,4'-biimidazole moiety depending on the protonated states. Neutral 4,4'-biimidazole possessed a linear chain mode of hydrogen-bonding to construct two-dimensional network. In the TCNQ salt of monoprotonated 4,4'-biimidazolium, the 4,4'-biimidazole moiety formed a dimer by a complementary mode of hydrogen-bonding. In contrast, the salt of diprotonated 4,4'-biimidazolium showed a double linear chain mode of hydrogen-bonding to construct a three-dimensional network. The formation of two types of hydrogen-bonding modes made the difference in the stacking patterns of TCNQ columns and in their transport properties. The TCNQ salt of diprotonated 4,4'-biimidazolium exhibited high electrical conductivity (sigma(rt) = 1.1 x 10(-1) S cm(-1)).     

Synthesis and luminescence properties of the europium quaternary complexes nanoparticles

In this paper,the nanometer-sized(200 nm)quaternary rare-earth complex Eu(BA)(TTA)2phen was successfully prepared by using the method of optimizing chemical precipitation.The characterizations of these nanoparticles were performed by using elemental analysis,thermogravimetric analysis,infrared spectroscopy,fluorescence spectroscopy,transmission electron microscopy and luminescence quantum-yield.The results indicate that they are better than common ternary complexes at light-emitting performance,luminescence properties,thermal stability,uniformity and particle size;they can also be further mixed with a suitable polymer to form functional rare earth polymers.Compared to the common solid materials,the quaternary complex has better and unique characteristics such as nanoparticle size effect and surface effect.A foundation had been laid for the further expansion of its application in the field of light-emitting and magnetic materials.     

溴化苄基取代吡啶类季铵盐的制备和抗菌性能

抗菌材料和抗菌制品的研究与应用一直是世界各国研究的重要课题~([1-3]),其中有机抗菌剂占据主要地位.季铵盐是研究比较多的一类有机抗菌剂,它们表现出良好的物理性质,如胶束浓度低,黏弹性好和溶解性强~([4]),同时此类抗菌剂具有强效的抗菌作用~([5]),引起了人们的极大兴趣.季铵盐广泛应用于医药、卫生、食品、饲料工业、农业、纺织、塑料、橡胶、造纸、水处理、油田开采、涂料、日常生活等多种领域~([6-10]).     

胺铜或镍配离子的TCNQ电荷转移盐的合成和物理性质

合成了七个胺铜或镍配离子的TCNQ电荷转移盐[ML2][TCNQ]n(TCNQ=7, 7, 8, 8-四氰基对苯二醌二甲烷; n=2, 3;M=Cu, Ni; L=tn, pn, dien, dmtade)。通过元素分析、红外光谱、电子光谱、顺磁共振谱、光电子能谱、磁化率和电导率对这些电荷转移盐进行了表征。结果表明, 这些电荷转移盐分子中存在TCNQ^0和TCNQ^-且TCNQ^0与TCNQ^-之间存在相互作用, 部分电荷从[TCNQ]n^2向[ML2]^2^+转移, 导致化合物中的金属表现为混合价态。七个样品的室温电导率在10^-^5～10^-^1^0S.cm^-^1, 属于有机半导体, 其导电性主要归结为一维TCNQ分子柱的形成。     

Semiconducting polymers based on charge-transfer complexes. I. Synthesis of electron-donor-containing poly-N-acylethylnimines

Polymers were made which contained 10-methyl, 3-phenothiazinyl, and 4-(methylthio)phenoxy electron-donating groups on side chains. N-Acyl-substituted poly-ethylenimines were chosen because the repeat distance along the polymer chain is the same as the repeat distance in most aromatic charge-transfer complexes (about 6.4 Å) and the side chains do not interfere with each other. This paper describes synthetic routes for preparation of these electron-donor-containing polymers. Synthesis of a polyacrylate donor is also described.     

Synthesis and biological activity of quaternary phosphonium salts based on 3-hydroxypyridine and 4-deoxypyridoxine

Methods for the synthesis of quaternary phosphonium salts based on 3-hydroxypyridine and 4-deoxypyridoxine were developed. Some of obtained compounds possess high antibacterial and antitumor activity in vitro.     

硝基芴桐类化合物与芳香胺相互作用的电子吸收光谱研究

本文研究不同结构的芳香胺和硝基芴酮形成的基态电荷转移复合物, 讨论结构和溶剂对基吸收光谱的影响.     

Semiconducting polymers based on charge-transfer complexes. III. Complexing and chemical stability of charge-transfer complexes in solution

10-Methylphenothiazine and p-(methylthio)anisole were compared to polymers which contained these donor molecules on the side chains of N-acyl-substituted polyethylenimines. Charge-transfer absorption spectra were compared for these donors with the acceptors: dichlorodicyanobenzoquinone, tetracyanoquinodimethane, tetracyanoethylene, and 2,4,5,7-tetranitrofluorenone. Benesi-Hildebrand plots show that the formation of the polymer complexes have 3 to 50 times higher equilibrium constants than those of the corresponding model complexes. This can be explained by complexing parallel to the polymer backbone. The polymer has the proper geometry for complexing (6.4 Å, repeat distance in the polymer backbone), and an acceptor molecule can therefore be inserted between two adjacent donor molecules for increased stability. Shifts of the absorption maxima to longer wavelength for some of the polymer complexes can be rationalized by the probability that in the polymer, an acceptor is sandwiched between two donors and thus forms 2:1 complexes; the extra resonance energy may shift the absorption maximum to longer wavelength. A second possible explanation is based on solvation of the complex which reduces the energy of the excited state. Polymers absorb mainly in the complex form. Model compounds absorb mainly by contact charge transfer, which is nonsolvated and thus occurs at higher energy or shorter wavelength. Extinction coefficients are higher for the model complexes than for the polymer complexes. Contact charge transfer, which can contribute in greater proportion to the model than to the polymer complexes, explains this. The amount of contact charge transfer can be calculated simply from the probability of a donor being in the solvent shell of an acceptor. Complex decomposition rates were determined based on measuring changes in the intensities of the charge-transfer absorption spectra. Dichlorodicyanoquinone complexes were unstable, while the other complexes were stable.     

Preparation and properties of antibacterial ABS plastics based on polymeric quaternary phosphonium salts antibacterial agents

Antibacterial acrylonitrile‐butadiene‐styrene (ABS) plastics were prepared by adding polymeric quaternary phosphonium salts as antibacterial agents through a double screw extruder. The novel polymeric quaternary phosphonium salts (PBrMAP‐n) with alkyl chain length ranging from 3 to 11 were synthesized, and their chemical structures were confirmed by Nuclear magnetic resonance hydrogen spectroscopy (¹H‐NMR) and Fourier transform infrared spectroscopy (FT‐IR) spectra. The thermogravimetric analysis (TGA) results showed that all of the antibacterial agents had good thermal stability. The influence of addition amount as well as the alkyl chain length on mechanical properties and antibacterial properties was investigated. Compared with the pure ABS, all of PBrMAP‐n containing specimens had comparable tensile strength and flexural properties but reduced impact strength. Only samples with 10 wt% of PBrMAP‐11 exhibited more than 90% antibacterial efficiency against Escherichia coli and Staphylococcus aureus.     

Palladium extraction from nitrate solutions by tertiary amines and quaternary ammonium salts

The mechanism of palladium extraction by trilaurylamine and trilaurylmethylammonium nitrate from nitric acid solutions was studied. The composition of the extracted compounds was determined by the Job method as well as by organic phase saturation. Both reagents were found to extract palladium as Am₂Pd/NO₃/₄ /Am=ammonium cation/.