Effect of matrix domination in PANI interpolymer complexes with polyamidosulfonic acids

Various polyaniline (PANI) interpolymer complexes with polyacids in the form of molecular solutions were synthesized by chemical oxidative polymerization of aniline in the presence of water-soluble poly-(2-acrylamido-2-methyl-1-propanesulfonic acid) (flexible backbone), poly-p,p′-(2,2′-disulfoacid)-diphenylene-terephthalamide (t-PASA, rigid backbone), and their mixtures in different ratios. The complexes were characterized by UV-Vis-near infrared spectroscopy in solutions; also, the films’ drop-casts from these solutions were investigated by cyclic voltammetry, spectroelectrochemical, direct current (DC) conductivity, and atomic force microscopy (AFM) measurements. It was shown that the nature of polyacid affects the shape of spectra and the dynamics of their changes. The character of spectral changes during the matrix synthesis of PANI in the presence of mixtures of the rigid-chain and flexible-chain matrixes and the study of spectral properties of the obtained PANI solutions demonstrates the existence of the rigid-matrix domination effect in the process of formation of PANI interpolymer complexes. Spectral properties of the obtained PANI complexes with the mixtures of flexible-chain and rigid-chain polyacids of different ratios (3:1, 1:1, 1:3, and 1:6) are very similar to those ones for the complex with rigid-chain t-PASA. At the same time, there is a correlation between the electrical conductivity and morphology of the films of PANI complexes and their composition, the conductivity passing through a minimum for the complexes with the polyacid mixtures (6:1, 3:1, and 1:1).     

Preparation of polyaniline in the presence of polymeric sulfonic acids mixtures: the role of intermolecular interactions between polyacids

Polyaniline (PANI) was synthesized by chemical oxidation of aniline in the presence of mixtures of water-soluble poly(sulfonic acids) of different nature. Under these conditions, the use of polyacid templates leads to the formation of interpolymer complexes of PANI and polyacid mixtures. The obtained PANI complexes were characterized by UV, visible, near IR, and Fourier transform infrared spectroscopy. It was shown that the rigidity of the polyacid backbone and the composition of a polyacid mixture affect the electronic structure of PANI complexes and the duration of the induction period of aniline oxidation. Domination of the more rigid-backbone template in the synthesis of PANI complexes with mixtures of the rigid- and flexible-backbone polyacids was observed. According to the viscometry and FTIR spectroscopic data, the reason of the domination is the existence of the intermolecular interaction between the polyacids in the mixture. In this case, duration of the induction period of aniline oxidation was between these values for pure polyacids.     

Temperature-dependent synthesis, crystal structures, characterizations, and DFT calculations of two new copper(II) complexes with p-fluorobenzoic acid and 2,2′-bipyridine ligands

Two new copper(II) complexes, [Cu(p-FBA)₂(2,2′-bpy)]·(H₂O) (1) and [Cu(p-FBA)(2,2′-bpy)₂]·(p-FBA)₂ (2) {p-FBA = p-fluorobenzoic acid, 2,2′-bpy = 2,2′-bipyridine} have been obtained from an identical starting mixture using temperature as the only independent variable and characterized by X-ray single crystal diffraction as well as with infrared spectroscopy, elemental analysis, and thermogravimetric analysis. The results reveal that 1 has 1D infinite chain structure formed by O–H···O hydrogen bonds, while 2 features a 0D structure. Additionally, there exist C–H···O hydrogen bonds and π–π stacking interactions in 1, forming 2D supramolecular structure. Furthermore, density functional theory (DFT) calculations of the structures, stabilities, orbital energies, composition characteristics of some frontier molecular orbitals and Mulliken charge distributions of the [Cu(p-FBA)₂(2,2′-bpy)] of 1 and [Cu(p-FBA)(2,2′-bpy)₂]⁺ cation of 2 were performed by means of Gaussian 03W package and taking B3LYP/lanl2dz basis set.     

Interpolymer complexes of copolymers of vinyl ether of diethylene glycol with poly(acrylic acid)

 The complex formation reactions of poly(vinyl ether of diethylene glycol) as well as vinyl ether of diethylene glycol–vinyl butyl ether copolymers with poly(acrylic acid) have been studied in aqueous and alcohol solutions. The formation of interpolymer complexes which were stabilized by hydrogen bonds was shown. The effects of molecular weight of poly(acrylic acid) and the nature of the nonionic polymer on the composition and stability of interpolymer complexes were clarified. The critical pH values of complexation were determined for different systems with various molecular weights and hydrophobic–hydrophilic balances. The stability of the interpolymer complexes formed in aqueous and alcohol solutions with respect to dimethylformamide addition was evaluated. The role of hydrophobic interactions and the presence of active groups on stability of the interpolymer complexes is discussed. Received: 23 July 2001 Accepted: 27 September 2001     

Preparation of nano-sized polybenzimidazole and carbon particles via poly(amino-amide) particles

Poly(amino-amide; PAA) particles consisting of p-phthalyl chloride and 3,3′-diaminobenzidine and 4,4′-diphenyldicarbony chloride and 3,3′-diaminobenzidine were prepared. The particles were then transformed by treatment with heat into poly(p-phenylenebenzimidazole; PPC–PAA) and poly(4,4′-diphenylenebenzimidazole; DPC–PAA) particles, respectively. The number ratio of ring-closing of the obtained product was found to be dependent on the processing temperature. However, the morphology and diameter of the products were not found to be temperature dependent. PPC–PAA particles were amorphous and DPC–PAA particles had a high degree of crystallinity. Further, upon heating up to 1,000 °C, poly(p-phenylenebenzimidazole) and poly(4,4′-diphenylenebenzimidazole) particles were transformed into carbon particles and carbon bulk, respectively. The poly(amino-amide), polybenzimidazole and carbon particles obtained were nano-sized spherical particles with narrow size distributions.     

The behavior of <Emphasis Type="Italic">p</Emphasis>-bis{3-[N-(3-chloro-buten-2-yl)pyrrolidinio(piperidinio or morpholinio)]propyn-1-yl}benzene dichlorides in an aqueous base medium

In aqueous base medium p-bis{3-[N-(3-chlorobuten-2-yl)pyrrolidinio (piperidinio or morpholinio)]-propyn-1-yl}benzene dichlorides undergo a two-way dehydrochlorination-cyclization reaction to form benzo[5,6-a:5′,6′-c]bis(2,2-tetramethylene- or -2,2-pentamethylene-4-methylisoindolinium) and benzo-[5,6-a:5′,6′-c]bisspiro(4-methylisoindoline-2,4′-morpholinium) dichlorides. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 546–549, April, 2009.     

A highly specific polyclonal antiserum to the environmental contaminant 1,1,1-trichloro-2,2-bis-(4-chlorophenyl)-ethane (p,p′-DDT)

A very selective polyclonal antiserum against 1,1,1-trichloro-2,2-bis-(4-chlorophenyl)-ethane (p,p′-DDT) was obtained by a careful choice of the haptenic structure (2,2-bis(4-chlorophenyl)-ethanol hemisuccinate). This hapten was conjugated to BSA to prepare the immunogen. The effects of different types of solid phases on the equilibrium reaction between the hapten on solid phase and the polyclonal antiserum were evaluated to obtain a fine tuning of the antiserum performances in terms of specificity for p,p′-DDT and sensitivity to low levels of this pesticide. The calibration curves obtained show that it is possible to set up a sensitive assay for p,p′-DDT, employing a p,p′-dichlorodiphenylacetic acid-based solid phase, with a detection limit of 0.12 ng/mL and a working range of about 0.21–40 ng/mL. Selectivity towards several p,p′-DDT-related substances was good (o,p-DDT 17%, p,p′-DDD 1.2% o,p-DDD 6.3%, p,p′-DDE 6.7%). Received: 4 November 1996 / Revised: 9 June 1997 / Accepted: 16 June 1997     

The spectroelectrochemical behavior of films of polyaniline interpolymer complexes in the near infrared spectral region

In this work, we carry out spectroelectrochemical studies of films of interpolymer complexes of polyaniline (PANI) prepared via the chemical and electrochemical template polymerization of aniline in the presence of polyamide sulfonic acids with different structures. It is shown that their spectroelectrochemical behavior in the near infrared region depends on the rigidity of the chain of the polymer sulfonic acid matrix. Electrodeposited films of PANI complexes with a rigid-chain polyacid exhibit a more intense absorption in the near infrared region (1000–2200 nm) and a less intense absorption in the absorption region of localized polarons (around 750 nm) in comparison with complexes with a flexible-chain polyacid. The comparison of the dependence of absorption in the near infrared region on potential with the cyclic voltammetry curves suggests that the chromophores responsible for this absorption are radical cations in nature. In the spectra of the films of chemically synthesized PANI complexes with a flexible-chain polyacid, during a long-term cycling in the region of potentials of the first redox stage of PANI, the absorption in the near infrared region which corresponds to delocalized polarons is also formed. This is apparently attributed to the intensification of the intermolecular interactions under the conformational fluctuations that accompany the change in the degree of oxidation of the film during cyclic voltammetry.     

Design of postmetallocene catalytic systems of aryliminetype for olefins polymerization: XIII. Synthesis of tetradentate bis(2-hydroxy-1-naphthaldimine) ligands and their complexes with titanium(IV) dichloride

Reactions of 2-hydroxy-1-naphthaldehyde with 1,4-diaminobutane, 1,6-diaminohexane, 4,4′-methylenedianiline and its alkyl- and cycloalkyl-sybstituted derivatives, with 4,4′-sulfonyldianiline, 2,2′- and 4,4′-oxydianiline, 4,4′-(1,4-phenylenebisoxy)dianiline, 4,4′-[propane-2,2-diylbis(1,4-phenylenebisoxy)]dianiline, and p-terphenyl-4,4″-diamine afforded a series of the corresponding diimines that at treating with TiCl₂(OPr-i)₂ formed mono- and binuclear complexes of titanium(IV) dichloride with tetradentate ligands LTiCl₂ and L₂(TiCl₂)₂.     

Synthesis and studies of spectroscopic and electrochemical properties of dinuclear ruthenium(<Emphasis Type="SmallCaps">II</Emphasis>) and manganese(<Emphasis Type="SmallCaps">II</Emphasis>) complexes

New dinuclear ruthenium manganese complexes of general composition (bpy)₂Ru(L)MnCl_x(H₂O)₂ (L is 1,10-phenanthroline-5,6-dione, 3,3′-dicarboxy-2,2′-bipyridyl, or bis(pyrazolyl); x = 2 or 4) were synthesized by the reaction of (bpy)₂Ru(L) with MnCl₂ · 4H₂O. These compounds and the starting mononuclear ruthenium complexes were studied by spectrophotometric and electrochemical methods in MeCN. The position of the charge-transfer band Ru^II → L in the spectra depends on the donor-acceptor characteristics of the ligand L. For the dinuclear complex under study, the formal potentials of reversible one-electron oxidation of Ru^II are in the range of 0.9–1.2 V (vs. the standard hydrogen electrode), whereas oxidation of Mn^II occurs at more positive (by 0.1–0.2 V) potentials. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2281–2285, October, 2005.     

Titanium(<Emphasis Type="SmallCaps">IV</Emphasis>) chloride complexes with chiral tetraaryl-1,3-dioxolane-4,5-dimethanol ligands as a new type of catalysts of ethylene polymerization

Titanium complexes of chiral ligands, (4R,5R)-2,2-dimethyl-α,α,α′,α′-tetraphenyl-1,3-dioxolane-4,5-dimethanol and its structural analogs, activated by polymethylalumoxane catalyze ethylene polymerization with an activity from 3 to 530 (kg polyethylene) (mol Ti h atm)⁻¹. An increase in the bulk of the aryl substituents results in a decrease in the catalytic activity of the complexes. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2275–2280, October, 2005.     

Crystal structure of the complex Zn(2,2′-Bipy)(C2H5OCS2)2 with mono- and bidentate ethylxanthate ligands

While seeking molecular precursors for ZnS films obtained by gas phase chemical deposition [1, 2] we synthesized mixed-ligand compounds ZnL(ROCS₂)₂ [R = i-Pr. /-Bu; L = 2,2′-bipyridyl (2,2′-Bipy), 1,10-phenanthroline (Phen)] [3]. The volatile complex Zn(2,2′-Bipy)(i-PrOCS₂)₂ was used as a precursor to obtain electroluminescent ZnS:Mn films [4]. According to XRD data, the compound Zn(Phen)(i-BuOCS₂)₂ is monomeric. The c.n. of zinc is six. The Phen and 1-B11OCS₂ ions behave as cyclic bidentate ligands [3, 5]. It was assumed that other mixed-ligand complexes with Phen and 2,2′-Bipy have an analogous structure [3]. Here we report on the structure of the known mixed-ligand complex of zinc(II) ethylxanthate with 2,2′-bipyridyl [6, 7]. It was found that the behavior of alkylxanthate ligands in mixed-ligand complexes of zinc(II) is more complex. Translated from Zhumal Stmktumoi Khimii, Vol. 41, No. 1, pp. 196-201, January–February, 2000.     

Chiral distinction in square planar Pt and Pd complexes of 2,2′-bipyridine derivatives

A computational study of square planar organometallic complexes formed by the ligand 2,2′-bipyridine and all its possible difluoro derivatives in analogous position of the aromatic rings (n,n′-difluoro-2,2′-bipyridine, where n = n′ = 3, 4, 5, and 6) and two M–X₂ (M = Pd and Pt and X = F, Cl, Br, and I) fragments has been carried out amounting to a total of 80 complexes. Relationships have been found between the chiral distinction energy and the different chemical moieties present. Using the statistical Free-Wilson method, the relative energies between the diastereomeric complexes have been correlated with the position of the substituent, the counter anion, and the central metal cation.     

Synthesis and electrochemical behavior of polyaniline doped by electroactive anions

Electrochemical potentiodynamic and potentiostatic synthesis was used to obtain polyaniline (PANI) doped by new electroactive anions (EAAs): organic dianion of the diammonium salt of 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfoacid) (ABTS) and inorganic ammonium hexachloroiridate dianion IrCl₆²⁻ (HCI). Two methods of electrochemical synthesis were studied: under constant potential (potentiostatic synthesis) and under potential cycling (potentiodynamic synthesis). The optimum ratio of EAA: principal electrolyte (1 M H₂SO₄) was found at which the maximum catalytic effect was obtained in the course of the synthesis and the principal properties of PANI obtained were preserved.     

Synthesis,spectroscopic and thermal properties of Pt(II) complexes of some polydentate ligands

The new tetradentate symmetrical (2R,2′S)-1,1′-piperazine-1,4-diyldipropane-2-thiol) (L¹), (2S)-1-[bis(2-aminoethyl)amino]propan-2-ol) (L²), and 2-{(E)-[((1R,2S)-2-{[(1Z)-(2-hydroxy phenyl)methylene]amino}cyclohexyl)imino]methyl}phenol (L³) ligands were synthesized and characterized on the basis of FT-IR, ¹H, ¹³C NMR, EI mass, and elemental analysis. Three commercially available ligands, (2,2′-[ethane-1,2-diylbis(thio)]diethanol (L⁴), 2,2′-dithiodiethanenamine (L⁵), and (2,2′-[ethane-1,2-diyldi(imino)] diethanol (L⁶), were also studied. Pt(II) complexes were characterized by FTIR, elemental analysis and thermal methods. Thermal behaviors of these complexes were investigated in the range 10–1000 °C. Magnetic properties were also studied, and the all complexes were found to be diamagnetic. The structures consist of the monomeric units in which the Pt(II) atoms exhibit square planar geometry. N,N′-bis(salicylidene)-1,2-cyclohexane has been synthesized and characterized by X-ray single crystal diffraction measurement. The ligand crystallizes in monoclinic crystal system and space group, Cc.     

An effective nanocomposite of polyaniline and ZnO: preparation,characterizations, and its photocatalytic activity

The polyaniline/zinc oxide (PANI/ZnO) nanocomposites were prepared by in situ polymerization of aniline monomer with ZnO nanomaterials and applied as a photocatalyst for the degradation of methylene blue (MB) dye. The morphological observations elicited the agglomerations of PANI sheets which occurred due to the interaction between PANI and ZnO nanomaterials in PANI/ZnO nanocomposites. As compared to pristine PANI, the UV–vis spectra exhibited that the absorption peak of π–π* transitions considerably shifted to higher wavelength at 360 nm from 325 nm in the nanocomposites. The photocatalytic activity results indicated the substantial degradation of MB dye by ~76% over the surface of PANI/ZnO nanocomposite catalyst under light illumination. The PANI/ZnO nanocomposites showed three times higher photocatalytic activity to MB dye degradation compared to pristine PANI might due to high photogenerated electron (ē)–hole (h⁺) pairs charge separation.     

Synthesis and photochromic properties of a new biindenylidenedione compound bearing hydroxylphenyl groups in crystal state

A new biindenylidenedione compound, named [trans-anti-3,3′-Di-p-hydroxyl phenyl-3,3′-dihydroxy-[2,2′-bi-1H-indene]-1,1′-dione] (2) was synthesized and characterized by means of ¹H-NMR, IR, MS and X-ray crystallographic diffraction techniques. The photochromic behavior was investigated by means of UV–Vis spectroscopy, and the results showed that the inclusion complex of 2 with guest solvent N,N-dimethylformamide (DMF) did not exhibit photochromism in crystal state. The structure–property relation was discussed briefly in context to the intermolecular interactions and the solvent-dependent effect on photochromism.     

Synthesis of water‐soluble conductive copolymer based on polyaniline

Synthesis and characterization of polyaniline‐grafted poly(styrene‐alt‐maleic anhydride) (PANI‐g‐PSMA) was carried out to obtain conductive comb copolymers with highly improved processability. First, polyaniline (PANI) was prepared in nano‐scale by chemical synthesis under ultrasonic irradiation. Then the poly(styrene‐alt‐maleic anhydride) (PSMA) was synthesized by free radical polymerization. Moreover, the PANI was grafted on the PSMA backbone to prepare a comb‐like conductive copolymer for improving its processability as a new method. The products were characterized by Fourier transform infrared, ultraviolet–visible spectroscopy and X‐ray diffraction patterns. Morphology of the samples was also investigated by scanning electron microscopy images. Finally, the solubility and conductivity of the products were studied, and it resulted in high solubility of the products in water and other common organic solvents in comparison to the pure PANI. Copyright © 2015 John Wiley & Sons, Ltd.     

Homopolymerization of <Emphasis Type="Italic">N</Emphasis>-vinylamides in the presence of water-soluble initiators and preparation of polyelectrolytes from the polymerization products

Homopolymerization of vinylformamide and N-methyl-N-vinylacetamide in water in the presence of 2,2′-azobis(2-methylpropanediamine) dihydrochloride and of the hydrogen peroxide-ammonium hydroxide system was examined. Hydrolysis of polyvinylformamide, poly-N-methyl-N-vinylacetamide, and poly-N-vinylacetamide with hydrochloric acid at 100°C was studied.     

Iridium(I)-Catalyzed Asymmetric Intermolecular Hydroarylation of Norbornene with Benzamide

 Starting from the dinuclear chloro-bridged Ir(I) complexes [IrCl(PP)]₂ (PP = (R)-(6,6′-dimethylbiphenyl-2,2′-diyl)-1,1′-bis-(diphenylphosphine), (R)-(6,6′-dimethoxy-biphenyl-2,2′-diyl)-1,1′-bis-(diphenylphosphine), and (R)-1-((S)-2-(diphenylphosphino-ferrocenyl))-ethyldicyclohexylphosphine), a new class of cyclopentadienyl Ir(I) complexes containing a chiral bisphosphine ([IrCp(PP)]) was prepared and characterized. These new complexes are suited precatalysts for the direct hydroarylation of norbornene with benzamide. 2-(exo-Norbornyl)-benzamide is formed with an enantiomeric excess of up to 94% by the use of 1 mol% iridium, albeit in low yield.