Copolymerization of N-Vinylsuccinimide with Butyl Methacrylate in Pyridine

The kinetics of radical copolymerization of N-vinylsuccinimide with n-butyl methacrylate in pyridine was studied, and the previously unknown copolymerization constants of the monomers were determined. The calculations were performed using appropriate software and a new procedure for approximation of the experimental data, which allow determination of the kinetic parameters at high conversions with the minimum error. The copolymerization kinetics were compared for the reaction systems constituted by N-vinylsuccinimide and n-butyl methacrylate and by N-vinylsuccinimide and n-butyl acrylate.     

Controlled radical polymerization of N-vinylpyrrolidone and N-vinylsuccinimide under the conditions of reversible chain transfer by the addition-fragmentation mechanism

Regular trends in controlled radical polymerization of N-vinylpyrrolidone and N-vinylsuccinimide by the mechanism of reversible chain transfer in the presence of a series of dithiobenzoates and trithiocarbonates were studied. The possibility of preparing soluble poly-N-vinylsuccinimide in concentrated solutions using benzyl benzodithioate as reversible chain-transfer agent was demonstrated.     

Copolymerization of N-vinylsuccinimide with butyl acrylate in an electron-donor medium of tertiary aminese

The effect of electron-donor solvents on the parameters of the NMR signals of vinyl protons in N-vinylsuccinimide and butyl acrylate was examined. The kinetics of copolymerization of N-vinylsuccinimide with butyl acrylate in triethylamine and tributylamine was studied by monitoring the running concentrations of the monomers in the course of the reaction. The copolymerization constants were calculated. The diad and triad composition of the copolymers formed in the medium of tertiary amines was predicted, and their microstructural nonuniformity was evaluated.     

Influence of the Reaction Medium on the Kinetics of Copolymerization of N-Vinylsuccinimide with Butyl Acrylate

Radical copolymerization of N-vinylsuccinimide with n-butyl acrylate in pyridine and the influence of donor characteristics of the solvent on the reaction kinetics were studied. The kinetics of copolymerization in various solvents (dichloroethane, dimethyl sulfoxide, and pyridine) were studied.     

A <Superscript>1</Superscript>H NMR study of radical copolymerization of <Emphasis Type="Italic">N</Emphasis>-vinylsuccinimide with <Emphasis Type="Italic">n</Emphasis>-butyl acrylate in dimethyl sulfoxide

Kinetic features of radical copolymerization of N-vinylsuccinimide with n-butyl acrylate in dimethyl sulfoxide were studied by ¹H NMR spectroscopy. The dependences of the running concentrations of the monomers and of the “instant” and overall compositions of the copolymers on the reaction time were determined. The limiting conversions were established for correct analysis of the kinetic features of copolymerization at essentially different relative activities of the monomers. The copolymerization constants and the probability of alternation of the units in the copolymer chains were calculated. Original Russian Text E.V. Sivtsov, A.I. Gostev, N.A. Lavrov, 2007, published in Zhurnal Prikladnoi Khimii, 2007, Vol. 80, No. 10, pp. 1679–1682.     

Alternating polyampholytes prepared by hydrolysis of copolymer of maleic anhydride and N-vinylsuccinimide

Alternating polyampholytes (MA-VA) containing two acidic groups and one basic group were prepared by the copolymerization of maleic anhydride (M₁) and N-vinylsuccinimide (M₂) at 60°C with AIBN as the initiator, followed by acid hydrolysis with 1N hydrochloric acid at 140°C for 24 hr. The monomer reactivity ratios r₁ and r₂ are 0.025 and 0.06, respectively. The structure of polymers was discussed on the basis of the data of their elementary, infrared (IR), and thermal analyses and the binding ability of heavy metal ion. Polyampholytes were soluble in strong acidic and basic media but were precipitated in the pH range 3–4. An isoelectric point at pH 3 was determined by potentiometric titration and the turbidimetric method. By thermal treatment above 205°C the polyampholyte turned quantitatively into a cyclized lactam. This suggests that the polyampholyte MA–VA has an intramolecular hydrogen bond between the amino and γ-carboxyl groups. The binding of Cu²⁺ and Hg²⁺ by the polyelectrolyte was evaluated by equilibrium dialysis.     

Self-fixing medicinal films based on copolymers of N-vinylsuccinimide with n-butyl acrylate

The information on properties of films based on copolymers of N-vinylsuccinimide with n-butyl acrylate that are recommended as wound coverings was summarized. Atraumatic, gel-forming, gas-permeable elastic films that self-fix on skin were made from these copolymers by the method of pouring from solutions. As a result, the materials displaying antibacterial (dioxidin, furacylin, lincomycin, rifampicin) and anesthetic (trimecain, pyromecain, anesthesin, novocain) influences were prepared and investigated.     

Free-Radical copolymerization of N-vinylsuccinimide with butyl acrylate in the presence of zinc chloride and aluminum chloride

The free-radical copolymerization of N-vinylsuccinimide with butyl acrylate performed in dimethyl sulfoxide and benzyl alcohol in the presence of zinc chloride and aluminum chloride as complexing agents is studied. Under the given conditions, the reactivity ratios are determined. It is shown that zinc chloride influences the electron-density distribution only in butyl acrylate molecules. It is found that benzyl alcohol retards the total rate of polymerization. The character of the monomer-unit distribution in copolymer macromolecules is described.     

Lipophilic Diamides as Ionophores for Alkali and Alkaline Earth Metal Cations

A series of lipophilic N, N, N′,N′-tetrasubstituted diamides were prepared and their selectivity in solvent polymeric membranes was studied, cis-N, N, N′, N′-Tetraisobutylcyclohexane-1,2-dicarboxamide induces a selectivity in membranes for Li⁺over alkaline earth metal cations and other alkali metal cations by a factor of about 1000 and 100 respectively. The ionophore N, N′-diheptyl-N,N′-dimethylethylmalonamide is an attractive candidate for the use in microelectrodes for the determination of intracellular Mg²⁺-activities.     

Geminal systems. 50. Synthesis and alcoholysis of N-acyloxy-N-alkoxy derivatives of ureas,carbamates, and benzamides

Procedures were developed for the synthesis of N-acyloxy-N-alkoxy derivatives of ureas, carbamates, and benzamides by the reactions of the corresponding N-alkoxy-N-chloro derivatives with sodium carboxylates in MeCN. N-Chloro-N-ethoxy-p-toluenesulfonamide was inert in this reaction. Alcoholysis of N-acyloxy-N-alkoxy derivatives of ureas, carbamates, and tert-alkylamines afforded the corresponding N,N-dialkoxy derivatives, whereas alcoholysis of N-acetoxy-N-ethoxybenzamide gave rise to alkyl benzoates.     

Synthesis of 2-amino-4-imino-4,5-dihydrothiazoles from N-sulfonyl-α-chloroamidines and thiourea

A number of new and interesting 2-amino-4-(N-substituted)imino-4,5-dihydrothiazoles were synthesized by reacting thiourea (or thiourea hydrochloride) with N-alkyl- or N,N-dialkyl-N′-p-toluenesulfonyl-α-chloroacetamidines, where the N,N-alkyl groups were ethyl, cyclohexyl, benzyl, β-phenethyl, (3,5-dimethyl-1-adamantyl)-methyl, as well as N,N-dimethyl- and N,N-pentamethylene. Reactions of N-alkyl-N-p-toluenesulfonyl-2-chloroacetamidines (substituents being N-ethyl, N-benzyl and N,N-dimethyl) with thiourea hydrochloride in hot 2-propanol furnished 2-amino-4-(p-toluenesulfonyl)imino-4,5-dihydrothiazole (in 51, 60 and 65% yields, respectively) and the corresponding amine hydrochloride. In hot acetone or butanone, the reactions of these N-sulfonyl-2-chloroacetamidines with excess thiourea provided 2-amino-4-N-(alkyl or N,N-dialkyl)imminium-4,5-dihydrothiazole chlorides in 25–80% yield. The by-product from these reactions was p-toluenesulfonamide. The structures of the products were established by chemical transformations and spectral methods (nmr and mass spectra).     

Separation and identification of purine nucleosides in the urine of patients with malignant cancer by reverse phase liquid chromatography/electrospray tandem mass spectrometry

Urinary‐modified nucleosides have a potential role as cancer biomarkers for a number of malignant diseases. High performance liquid chromatography (HPLC) was combined with full‐scan mass spectrometry, MS/MS analysis and accurate mass measurements in order to identify purine nucleosides purified from urine. Potential purine nucleosides were assessed by their evident UV absorbance in the HPLC chromatogram and then further examined by the mass spectrometric techniques. In this manner, numerous modified purine nucleosides were identified in the urine samples from cancer patients including xanthine, adenosine, N1‐methyladenosine, 5′‐deoxy‐5′‐methylthioadenosine, 2‐methyladenosine, N6‐threonylcarbamoyladenosine, inosine, N1‐methylinosine, guanosine, N1‐methylguanosine, N7‐methylguanine, N2‐methylguanosine, N2,N2‐dimethyguanosine, N2,N2,N7‐trimethylguanosine. Furthermore, a number of novel purine nucleosides were tentatively identified via critical interpretation of the combined mass spectrometric data including N3‐methyladenosine, N7‐methyladenine, 5′‐dehydro‐2′‐deoxyinosine, N3‐methylguanine, O6‐methylguanosine, N1,N2,N7‐trimethylguanosine, N1‐methyl‐N2‐ethylguanosine and N7‐methyl‐N1‐ethylguanosine. Copyright © 2009 John Wiley & Sons, Ltd.     

Water-Soluble imide-amide copolymers. III. Preparation and characterization of poly (acrylamide-co-N,N-diallylaniline) and poly (acrylamide-co-sodium N,N-diallylsulfanilate)

N,N-diallylaniline monomer was prepared in good yields, for use in preparation of homopolymer and for copolymerization with acrylamide. Functionalized N,N-diallylaniline monomer, as sodium N,N-diallylsulfanilate, was also prepared in good yields for copolymerization with acrylamide. Both monomers were fully characterized by elemental analysis, IR, and NMR. Poly (N,N-diallylaniline) was obtained by polymerization of a strongly acidic aqueous solution of N,N-diallylaniline initiated with hydrogen peroxide. Spectroscopic data from this homopolymer was used to facilitate spectral assignments of the new copolymers. Copolymers of acrylamide with N,N-diallylamine were prepared at monomer feed ratios of 10, 20, and 30 mol % amine and gave 3.5, 7.4, and 8.9 mol % incorporation, respectively. Similar diallyl monomer incorporation rates were obtained for the copolymerization of sodium N,N-diallylsulfanilate with acrylamide. With 10, 30, and 50 mol % of the sodium salt relative to acrylamide, 3.9, 8.4, and 19.2 mol % incorporation of the diallyl monomer was obtained.     

Novel synthesis of polymeric phase transfer catalysts containing N,N-dialkylacrylamide unit and their catalytic activity

Soluble polymeric phase transfer catalysts (PTCs) containing benzyltributylphosphonium chloride moieties and polar N,N-dialkyl-acrylamide with long alkyl groups such as N,N-dipropylacrylamide, N,N-dibutylacrylamide, N,N-dihexylacrylamide, and N,N-dioctylacrylamide were prepared via two-step reactions from p-chloromethylstyrene and the corresponding N,N-dialkylacrylamide. When the obtained polymers were added, the phase transfer catalyzed reaction of benzylchloride with solid potassium acetate to proceed smoothly. The catalytic activity was strongly affected by the content of phosphonium chloride and the varieties of comonomer unit in the polymeric PTC. The polymeric PTC containing the N,N-dihexylacrylamide unit showed excellent high catalytic activity in a low polar solvent such as the mixed solvent of toluene with 70 vol % n-tridecane. Therefore, the polymer containing lipophilic long chains such as the hexyl group is desirable for polymeric PTC. © 1996 John Wiley & Sons, Inc.     

N-Methacryloylaminodeoxyglucose Copolymers Containing Unsaturated Acid and Activated Ester Units

Copolymers of N-methacryloylaminodeoxyglucose with acrylic and methacrylic acids were prepared by radical copolymerization. The reactions of these copolymers with p-nitrophenol, N-hydroxysuccinimide, and N-hydroxyphthalimide in the presence of N,N'-dicyclohexylcarbodiimide were studied.     

The solvent effect on the isotropic hyperfine interaction in some aliphatic polyamine copper(II) complexes

ESR and optical absorption studies are described for a number of copper(II) chelates with aliphatic polyamines, exhibiting both square pyramidal and square bipyramidal coordination around the copper ion. The complexes studied were bis(N,N′-dimethylethylenediamine)copper(II) sulphate tetrahydrate, bis(N,N′-diethylethylenediamine)copper(II) nitrate, diaquosulphato(N,N,N′,N′-tetramethylethylenediamine)copper(II) hydrate, dinitrato(N,N,N′,N′-tetramethylethylenediamine)copper(II), dichloro(N,N,N′,N′-tetramethylethylenediamine)copper(II) and dithiocyanato(N,N,N′,N′-tetramethylethylenediamine)copper(II). The ESR measurements were carried out in methanol, dimethyl sulphoxide, dimethylformamide and pyridine, at room and liquid nitrogen temperatures. The molecular orbital coefficients were estimated assuming an axial symmetry. The parameter χ proportional to the hyperfine constants shows a variation with the solvent for all these complexes. The χ values in solution are lower than the corresponding average χ values reported in the solid state for each complex. The solvent effect and the influence of 4s character in the ground state are discussed. The χ values, either calculated or reported, for a number of copper complexes for [4O], [3O, N], [2O, 2N], [O, 3N] and [4N] environments around copper(II) are presented.     

Three gemini cationic surfactants as biodegradable corrosion inhibitors for carbon steel in HCl solution

Three gemini cationic surfactants with different hydrophobic spacer chain lengths were synthesized and characterized. The inhibition effect of N,N′-bis(2-hydroxyethyl)-N,N′-dimethyl-N,N′-bis(2-(tetradecanoyloxy)ethyl)ethane-1,2-diaminium bromide (G-2); N,N′-bis(2-hydroxyethyl)-N,N′-dimethyl-N,N′-bis(2-(tetradecanoyloxy)ethyl) hexane-1,6-diaminium bromide (G-6); and N,N′-bis(2-hydroxyethyl)-N,N′-dimethyl-N,N′-bis (2-(tetradecanoyloxy) ethyl) dodecane-1,12-diaminium bromide (G-12) on the corrosion of carbon steel in 1.0 M HCl solution at 25–60 °C was studied by weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy. The results show that the synthesized inhibitors are effective inhibitors even at very low concentration, and the adsorption on the carbon steel surface obeys the Langmuir adsorption isotherm. Potentiodynamic polarization curves reveal that the synthesized inhibitors behave as a mixed-type inhibitor. Adsorption of used inhibitors led to a reduction in the double layer capacitance and an increase in the charge transfer resistance. Thermodynamic parameters have been obtained by adsorption theory. Surface activity and corrosion inhibition relationship were discussed. The biodegradability of the synthesized surfactants showed their readily biodegradation in the open environment and were considered as environmentally friendly corrosion inhibitors.

     

Radical polymerization of N-substituted itaconamic esters and itaconamides

Two kinds of itaconamic esters, α-substituted acrylate derivatives (IAE-I) and α-substituted acrylamide derivatives (IAE-II), as well as itaconamides (IAm) were prepared and polymerized with a radical initiator. It has been revealed that N,N-disubstituted IAE-I as an acrylate is more reactive in polymerization than N,N-disubstituted IAE-II as an acrylamide and that N,N′-dialkyl substituted IAm homopolymerizes but N,N,N′,N′;-tetraalkyl substituted one does not. In radical copolymerization with styrene, IAE-I showed a higher polymerization reactivity than IAE-II. The effects of the N-substituents on the polymerization reactivity were discussed on the basis of conformation of the monomers. The polymers obtained were also characterized. © 1994 John Wiley & Sons, Inc.     

Proton NMR spectroscopy of asymmetric benzylamines. The long-range effects of an asymmetric environment

¹H NMR Spectra of the asymmetric benzylamines N-benzyl-N-butyl-2-hydroxy-1,3-propandiamine, N-benzyl-N-(2-ethylhexyl)-2-hydroxy-1,3-propandiamine, N-benzyl-N-butyl-2,3-epoxypropanamine and N-benzyl-N-(2-ethylhexyl)-2,3-epoxypropanamine, were analysed. A pronounced non-equivalance of the benzylic hydrogens is induced by asymmetric carbons in γ position with respect to the benzylic group. [Δδ=0.2–0.3 ppm; J(AB)～13.5 Hz]. Two sets of AB patterns were observed when two asymmetric carbons were present in the same molecule. RS+SR Diastereomers can thus be distinguished from the RR+SS enantiomers.     

Synthesis, X-Ray Diffraction Data, and 1H and 13C NMR Spectra of N-(N-Arylsulfonylimidoyl)-1,4-benzoquinonimines Derived from N-Aroyl(acetyl)-1,4-benzoquinonimines

Oxidation of N-(N-arylsulfonylimidoyl)-4-aminophenols gave the corresponding N-[N-arylsulfonylimidoyl)-1,4-benzoquinonimines, derivatives of N-aroyl- and N-acetyl-1,4-benzoquinonimines. The structure of the products was studied by the X-ray diffraction method and ¹H and ¹³C NMR spectroscopy. N-(N-Arylsulfonylimidoyl)-1,4-benzoquinonimines were found to undergo fast (on the NMR time scale) Z E isomerization about the CÍN bond in the quinonimine fragment. N-(N-Arylsulfonylacetimidoyl)-1,4-benzoquinonimines in solution give rise to dynamic Z E-isomerization with respect to the CÍN bond in the N-arylsulfonylacetimidoyl fragment.