A passive chemical dosimeter for assessing long-term exposure in air containing aniline and aniline derivatives

A passive chemical dosimeter for assessing long-term exposure to toxic substances (aniline and its derivatives) in the atmosphere of inhabitable premises was described. The compounds to be determined were accumulated on an absorption filter due to a chemical reaction with a selective agent upon the many-hour exposure of the device. Analytical performance of chemical dosimeters (diffusion coefficients, chemisorption pre-concentration rate, and detection limits) was evaluated. The concentrations of aniline, p-chloroaniline, 3,4-dichloroaniline, and o-toluidine in the air of chemical laboratories and smoking rooms were determined.     

Electrochemical and chemical synthesis of nanostructure copoly(aniline-o-anisidine-o-toluidine) and study of its electrochemical behavior in organic sulfonic acid media

Terpolymerization of aniline, o-anisidine and o-toluidine was carried out by electrochemical and interfacial chemical polymerization. All homopolymers and terpolymer thin films have been synthesized through electropolymerization at room temperature in aqueous solutions containing 0.5 M of organic sulfonic acid, such as p-toluene sulfonic acid, methane sulfonic acid, sulfosalicylic acid, dodecylbenzene sulfonic acid, and 0.1 M of aniline, o-anisidine and o-toluidine monomers, using cyclic voltammetry method, applying a sequential linear potential scan at a rate of 25 mV s^?1 between ?0.1 and 0.9 V. The electrochemical terpolymerization has been performed at various mole ratios of monomers. Nanoparticles obtained from conjugation of homo- and terpolymer with organic sulfonic acids, were prepared by a chemical oxidation via interfacial chemical polymerization. SEM micrographs, FTIR spectra and conductivity measurements using four-probe method were applied for the characterization of the products. Terpolymer was characterized by higher conductivity than poly-o-toluidine and lesser than polyaniline and poly-o-anisidine. The solubility of terpolymers was dependent on the monomers mole ratio.     

Topological and thermodynamic investigations of molecular interactions of aniline and o-toluidine with chloroform

Molar excess volumes, V^E, molar excess enthalpies, H^E, and speeds of sound data, u, of chloroform (i) + aniline or o-toluidine (j) binary mixtures have been measured as a function of composition at 308.15 K. Isentropic compressibility changes of mixing, have been determined by employing speed of sound data. Topological investigations of V^E data reveals that aniline, chloroform and o-toluidine are associated entities and these (i + j) mixtures contain a 1:1 molecular complex. The IR studies lend further support to the nature and extent of interaction for the proposed molecular entity in the mixtures. H^E and values have also been calculated by employing Moelwyn-Huggins concept [Polymer 12 (1971) 387] taking topology of the constituents of the mixtures. It has been observed that calculated H^E and values compare well with their corresponding experimental values. The observed V^E, H^E and data have also been analyzed in terms of Flory theory.     

Antipyrilquinoneimine dye formation by coupling aniline derivatives with 4-aminoantipyrine in the presence of ruthenium nanoparticles

The coupling of 4-aminoantipyrine (4-AAP) with aniline derivatives catalyzed by ruthenium nanoparticles (Rnp) has been studied by UV-Vis spectroscopy in aqueous medium. The rate constant for antipyrilquinoneimine dye formation depends on the nature of the aniline substituent and the pH, ionic strength and temperature of the reaction medium. The maximum rate constant of the dye formation reaction is observed at pH 3.6. Aniline derivatives with electron donating substituents show higher rate constant values than those with electron withdrawing substituents, with increasing rate constant values in the order: N,N-dimethyl aniline > o-toluidine > o-chloroaniline > m-chloroaniline. With pseudo first order kinetics, the total order is 1.0 + 1.0 + 1.0 = 3.0, which includes the orders with respect to amine, 4-AAP and Rnp. Studies on these effects help to complete the kinetic analysis as well as propose the reaction pathway. Furthermore, TEM measurement confirms that the nanoscalar size of the Rnp is 7 nm.     

Heats of mixing of some binary methylene chloride solutions

Heats of mixing of pyridine, α-picoline, aniline, o-toluidine and cyclohexane with methylene chloride have been measured at 298.15 K. The results have been considered in terms of molecular interactions between the components of these mixtures and possible structures of the complexes have been described.     

Mixing Behavior of Cationic Hydrotropes with Anionic Surfactant Sodium Dodecyl Sulfate

Mixing behavior of anionic surfactant sodium dodecyl sulfate (SDS) with cationic hydrotropes aniline hydrochloride (AH), o-toluidine hydrochloride (o-TH), and p-toluidine hydrochloride (p-TH) have been studied using conductivity at different temperatures. Critical micelle concentration for different mixing mole fractions, their ideal values, and different interaction parameters have been estimated. All the parameters show nonideal behavior with synergistic interactions. Thermodynamic parameters are also calculated for these systems.     

Infrared spectra of bis(aniline) and bis (p-toluidine) metal(II) isothiocyanate complexes

The infrared spectra of eight complexes of general formula [ML₂(NCS)₂] (M = Co, Ni, Cu, Zn; L = aniline or p-toluidine) have been determined over the range 4000–4150 cm^?1. Colour, magnetic moments and IR spectra are consistent with polymeric octahedral coordination in the Co(II) and Ni(II) complexes and polymeric tetragonal coordination in the Cu(II) complexes, while the Zn(II) complexes are assigned polymeric octahedral (L = aniline) and tetrahedral (L = p-toluidine) structure on the basis of their IR spectra. Independent ¹⁵N-labelling of the nitrogen atoms of the amino and isothiocyanate groups yields assignments for the internal vibrations of both groups and enables the metal-amine and metal—isothiocyanate stretching vibrations (vM-NH₂ and vM-NCS) to be distinguished. Both vM-NH₂ and vM-NCS are metal ion dependent in the Irving-Williams sequence (Co < Ni < Cu > Zn) expected from their proposed structures while the vN-H and vN-CS vibrations are inversely related to the masses of the coordinated metal ions.     

Synthesis and physicochemical studies on Co(III) complexes

Complexes of Co(III) with 2-hydroxyacetophenone-thiosemicarbazone, 2-hydroxy-3-methylacetophenonethiosemicarbazone and 2-hydroxy-4-methyl-acetophenonethiosemicarbazone, and the addition complexes of 2-hydroxy-acetophenone thiosemicarbazone with ammonia, pyridine, aniline,o-toluidine,m-toluidine andp-toluidine have been synthesized and characterized on the basis of their conductivities, electronic and infrared spectral data. All complexes are low-spin octahedral in nature. Various parameters have been obtained using ligand field theory.     

A spectrophotometric study of molecular complexes of 2,3-dicyano-1,4-naphthoquinone

Molecular complexes of 2,3-dicyano-1,4-naphthoquinone with various aromatic anilines were studied spectrophotometrically in dichloromethane solvent at different temperatures. All these complexes show a new broad charge-transfer band in the visible region of the electromagnetic spectrum. All the donors are known to form strong 1:1 complexes with the acceptor and their stoichiometry was unaffected by the variation of temperature over a small interval. The thermodynamic and spectroscopic parameters were evaluated. The order of donor strength followed the sequence: 2,5-dimethylaniline > 2,3-dimethylaniline > N,N-dimethylaniline > p-toluidine > o-toluidine > m-toluidine > N-methylaniline > aniline.     

Molecular rearrangements—XII: Pyrolysis of α-phenylacetanilide

Pyrolysis of α-phenylacetanilide resulted in migration of the benzyl group to the o and p positions of the aniline nucleus and formation of CO, NH₃, toluene benzaldehyde, dibenzyl, trans stilbene, aniline, 9 phenylacridine and 2,3 diphenyl-indole. With o-toluidine as a solvent the previous products were accompanied by 2,3 diphenyl-7-methylindole and 4 amino 3 methyl diphenylmethane. With isoqumoline 1 benzyl isoquinoline and 1,1' bi-isoquinolyl were also obtained.It is concluded that the pyrolysis of phenylacetanilide depends on the homolytic fission of the amide C-N bond into anilino and phenylacetyl free radicals followed by the interaction of the primary and secondary formed radicals with the rearrangement products and solvent nuclei.     

Thermochemical studies for determination of the molar enthalpy of formation of aniline derivatives

The standard (p ^o=0.1 MPa) molar enthalpies of combustion atT=298.15 K were measured by static bomb combustion calorimetry for liquidN,N-diethylaniline,N,N-dimethyl-m-toluidine,N,N-dimethyl-p-toluidine, andN-ethyl-m-toluidine. Vaporization enthalpies forN,N-dimethyl-m-toluidine andN-ethyl-m-toluidine were determined by correlation gas chromatography. Derived standard molar values of _f H _m ^o (g) at 298.15 K forN,N-diethylaniline (62.1±7.6);N,N-dimethyl-m-toluidine (72.6±7.3),N,N-dimentyl-p-toluidine (68.9±7.4),N-ethyl-m-toluidine (30.5±3.8 kJ· mol^–1) were obtained.     

Synthesis and spectral characterization of some complexes of platinum(II) containing η-methyleugenol

Several complexes of the formula trans-[Pt(Meug)(Am)Cl₂], Meug: methyleugenol (4-allyl-1,2-dimethoxybenzene), a η²-coordinated olefin, and Am: ammine, methylamine, diethylamine, o-toluidine, m-toluidine, p-toluidine, o-anisidine, m-anisidine and p-anisidine have been prepared. UV, IR, Raman, ¹H NMR, ¹³C NMR and 2D NMR spectra of the complexes were recorded and analyzed.     

Bis(indenyl)titanium(IV) and zirconium(IV) complexes of monofunctional bidentate salicylidimines

Dichlorobis(indenyl)-titanium(IV) and -zirconium(IV), (C₉H₇)₂TiCl₂ and (C₉H₇)₂ZrCl₂, react with bidentate Schiff bases such as salicylidene aniline, salicylidene-o-toluidine, salicylidene-m-toluidine and salicylidene-p-toluidine in a 1:1 molar ratio in refluxing tetrahydrofuran in the presence of triethylamine to yield complexes of the type (C₉H₇)₂Ti(SB)Cl and (C₉H₇)₂Zr(SB)Cl, respectively where SB is the anion of the corresponding Schiff base, SBH. The new derivatives have been characterised on the basis of their elemental analyses, conductance measurements and spectral (IR, ¹H NMR and electronic) studies.     

Studies on some oxovanadium(IV) complexes of acyl pyrazolone analogues

A series of novel bidentate pyrazolone based Schiff base ligands were synthesized by interaction of 4-benzoyl-3-methyl-1-(4′-methylphenyl)-2-pyrazolin-5-one with various aromatic amines like aniline, o-,m-,p-chloroaniline and o-,m-,p-toluidine in a ethanolic medium. All of these ligands have been characterized on the basis of elemental analysis, IR and ¹H NMR data. The molecular geometries of five of these ligands have been determined by single crystal X-ray study. Crystallographic study reveals that these ligands exist in the amine-one tautomeric form in the solid state. NMR study also suggests the existence of the amine-one form in solution at room temperature. Ab initio calculations for representative ligand HL¹ has been carried out to know the coordination site of the ligand. Novel vanadium Schiff base complexes of these ligands with general formula [OV(L^1–7)₂(H₂O)] have been prepared by interaction of aqueous solution of vanadyl sulfate pentahydrate with DMF solution of the appropriate ligands. The resulting complexes have been characterized on the basis of elemental analysis, vanadium determination, molar conductance and magnetic measurements, thermo gravimetric analysis, infrared and electronic spectral studies. Suitable distorted octahedral structures have been proposed for these complexes.     

Kinetic analysis of thermogravimetric data. XVIII. Thermal decomposition of some [Co(AMINE)2 (NCS)2] type complexes

[Co(p-toluidine)₂(NCS)₂] (I), [Co(m-toluidine)₂(NCS)₂] (II) and [Co(aniline)₂(NCS)₂] (III) have been synthesized. Kinetic parameters n, E and Z (apparent reaction order, activation energy and pre-exponential factor) have been derived from the TG curves recorded under 12 different working conditions. The influence of the sample weight (m_o) and of the heating rate (q) upon the kinetic parameters as well as upon the decomposition temperature and the amount of amine liberated in the first decomposition stage are discussed. Mean values of the activation energy and of the decomposition temperature are discussed in terms of the Co—amine bond strength and molecular structure based on IR evidence.     

Highly conductive soluble terpolymers of aniline,toluidine, and o‐aminobenzoic acid/m‐aminobenzenesulfonic acid

Two series of terpolymers, one of o‐/m‐toluidine and aniline with o‐aminobenzoic acid and the other of o‐/m‐toluidine and aniline with m‐aminobenzenesulfonic acid, have been synthesized by oxidative polymerization via an emulsion method with ammonium persulfate as the oxidant and HCl as the external dopant. The terpolymers exhibit excellent solubility and retain the high conductivity (∼1 S cm⁻¹) characteristic of the unsubstituted homopolymer, polyaniline. The terpolymers also possess higher thermal stability than polyaniline. This can be attributed to the presence of internal doping groups and substituents, which introduce flexibility to the otherwise rigid polyaniline backbone. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3040–3048, 2005     

Synthesis and biological evaluations of some Schiff-base esters of ferrocenyl aniline and simple aniline

The synthesis and biological studies of some long chain esters containing Schiff bases and their ferrocenyl analogues were carried out. The 4-amino ferrocene was prepared by the reported method. Long chain esters were synthesized by the condensation of different aliphatic acids with the corresponding aldehyde. The esters were then reacted with aniline as well as with 4-aminophenyl ferrocene to give corresponding Schiff bases. All the synthesized compounds were analyzed by elemental, FTIR and proton NMR studies, were also investigated for a range of biological activities. Determined by crown gall tumor inhibition assay. Antioxidant and DNA protective activities were determined by DPPH free radical scavenging assay and OH radical induced oxidative DNA damage assay, respectively. Among all test compounds, o-hydroxy-p-n-octadecanoyloxy-benzylidine-p-ferrocenyl aniline (FA2.1: a ferrocene containing Schiff base) showed highest antitumor, DPPH free radical scavenging and DNA protective activities.     

In situ synthesis of copper nanoparticles and poly(o-toluidine): A metal-polymer composite material

We report here a novel in situ synthetic method for the preparation of poly(o-toluidine) and copper nanoparticle composite material. In this experiment, o-toluidine and cupric sulfate were used as the precursor; during the reaction o-toluidine was oxidized and forms poly(o-toluidine), while on the other hand cupric sulfate gets reduced and forms copper nanoparticle. IR, UV-vis and Raman spectra provide the information on the structure of the polymer. The TEM and SEM show the size of the nanoparticles and the morphology of the polymer, respectively.     

Voltammetric analysis of the possibility of derivatization of levodopa in the presence of aniline derivatives

Electrochemical oxidation of levodopa (LD) as one of the most well-known neurotransmitters has been studied in the presence of some aniline derivatives. The electron transfer of LD is followed by two competitive reactions in the presence of these amines. The reactions are the Michael additions of side chain amine group of LD and/or aromatic amines to electrochemically generated o-quinone. There are two ECE mechanisms for both pathways and the competition between these inter and intramolecular reactions drastically depends on the pH of the medium. The pH dependence of reactions has been studied and the observed homogeneous rate constants of the reactions were estimated by digital simulation of cyclic voltammograms. The effect of aniline substituents was also studied with regard to their reactivities toward o-quinone of LD and the competitive reactions. Based on the obtained results, the products of intermolecular reactions are electroactive diphenylamine derivatives and their half-wave potentials depend on the nature of the aniline substituent.     

Chemical synthesis and characterization of aniline and o-anthranilic acid copolymer

The chemical co-polymerization of aniline with o-anthranilic acid (AA) to form copolymer films has been made in aqueous hydrochloric acid medium. The copolymer films were monitored by using the quartz crystal microbalance (QCM) technique. The effect of AA and its concentrations on the film formation was investigated. The results were justified by measuring the UV-Vis absorption spectra for the in situ copolymer films grown onto glass slides immersed into the polymerization media and the in situ UV-Vis absorption spectra for the copolymer in the bulk during the co-polymerization. The conductivity for the copolymer films and powder pellets at different molar ratios of aniline/AA were measured. Also, the IR spectra, X-ray diffraction and the thermal gravimetric analysis for the copolymer powder formed in the bulk in the absence and presence of AA were measured and discussed. It is found that the presence of AA affects the yield, induction period, depletion time and growth rate of the film formation. It also affects the crystallinity, and conductivity as well as the solubility of the polymer. Finally, the dopant weight fraction (w) associated with the copolymer was determined. It is almost half the value determined for the polymer in absence of AA.