Copolymerizations of 2-hydroxyethyl methacrylate with alkyl methacrylates

Copolymerizations of 2-hydroxyethyl methacrylate with ethyl methacrylate and n-butyl methacrylate were studied in bulk at temperatures between 60 and 80° using benzoyl peroxide as initiator. The monomer reactivity ratios were calculated using Joshi-Joshi, Fineman-Ross and intersection methods. The temperature had only a marginal effect on the reactivity ratios.     

Reaction of vinylpyridines with oxazoles

Depending on the structure, the reaction of the hydrochlorides of 2- and 4-vinylpyridines and 2-methyl-5-vinylpyridine with oxazoles leads to the synthesis of dipyridyls with or without a hydroxy group. It is shown that the regiospecificity of the reaction can be predicted on the basis of quantum-chemical calculations with the aid of the concepts of MO perturbation theory.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1255–1262, September, 1980.     

Copolymerizations of alkyl methacrylates with vinyltriacetoxysilane

Copolymerizations of methyl methacrylate (MMA) and butyl methacrylate (BMA) with vinyltriacetoxysilane (VTAS) have been carried out in bulk at 70°. The compositions of the copolymers were determined from their silicon contents; the reactivity ratios were calculated by the Kelen-Tüdős method. For MMA/VTAS, r₁ = 7.75 ± 0.31 and for BMA/VTAS, r₁ = 4.62 ± 0.15; in both systems, r₂ is zero, indicating that VTAS does not homopolymerize under the experimental conditions. The influence of the silicon comonomer on properties of the copolymers, such as solubility annd thermal behaviour, was studied.     

Cyclodimerization of vinylpyridines

When isomeric 2- and 4-vinylpyridines, as well as 2-methyl-5-vinylpyridine, are heated in polyphosphoric or acetic acid, they undergo dimerization, which proceeds via a 1,4-cycloaddition scheme to give pyridyl-substituted 5,6,7,8-tetrahydroquinclines or isoquinolines. Quantum-chemical calculations with the use of the concepts of molecular orbital perturbation theory make it possible to predict the regiospecificity of the reaction. The regiospecific cross cycloaddition of 4-vinylpyridine to 2-methyl-5-vinylpyridine was proposed theoretically and proven experimentally.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1248–1254, September, 1980.     

Base- and acid-catalyzed condensation reactions of reissert compounds with vinylpyridines

The hydrochloric acid-catalyzed condensation of 2-p-anisoyl-1,2-dihydroisoquinaldonitrile ( 3 ) with 2-vinylpyridine gave 2-(1-isoquinolyl)-3-(2-pyridyl)-5-p-anisylpyrrole ( 4 ), and the corresponding reaction of 3 with 4-vinylpyridine afforded 2-(1-isoquinolyl)-3-(4-pyridyl)-5-p-anisylpyrrole (5). The condensation of the lithium salt of 3 with 4-vinylpyridine gave α-(4-pyridyl)-β-(1-iso-quinolyl)-p-methoxypropiophenone ( 10 ), which was cyclized to 2-(4-pyridyl)-3-p-anisylpyrrolo-[2,1-a]isoquinoline (7) by the action of concentrated hydrochloric acid. 2-(4-Pyridyl)-3-phenyl-pyrrolo[2,1-a]isoquinoline ( 6 ) and 2-(2-pyridyl)-3-p-anisylpyrrolo[2,1-a]isoquinoline ( 8 ) were prepared by analogous sequences of reactions.     

Preparation of N-substituted amidines2

N-substituted amidines can be prepared in good yield by heating equimolecular quantities of aryl nitriles and primary amines with AlCl₃. Also when a nitrile is kept at room temperature in contact with hydrogen chloride gas in dry ether in the presence of arylamine, amidines may be formed in good yields.     

Cyclodimerizations and Copolymerizations of Vinyl Ketones with Vinyl Monomers

Stable high-molecular-weight polyacetals can be prepared from formaldehyde or from its trimer trioxane.     

Synthesis of N-substituted 2-benzoxalones

3-Acetylaminomethyl-2-benzoxazolones are obtained by Beckmann rearrangement of the anti-oximes of 3-acetonyl-2-benzoxazolones. The isomeric 3-(N-methylcarbamoylmethyl)-2-benzoxazolones are synthesized by alkylation of 2-benzoxazolone with chloroacetic acid, followed by reaction of the 3-carboxymethyl-2-benzoxazolones obtained with thionyl chloride and methylamine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1185–1188, September, 1985.     

Vinyl Polymerization. 401. Polymerization of Vinyl Monomer Initiated with Poly-2-hydroxyethylmethacrylate

The polymerization of vinyl monomer initiated with poly-2-hydroxyethylmethacrylate (PHEMA) in water was carried out at 85°C. Cu(II) ion was not necessary for this polymerization. Methacrylate monomers were polymerized, while styrene and acrylonitrile were not. The polymerization was found to proceed through a radical mechanism in the interior of PHEMA which was swelled in water. The grafting efficiency of MMA polymer obtained was about 90%. The overall activation energy was estimated to be 32.9 kJ/mol.     

Thermomechanical properties of polymeric composites based on 2-hydroxyethylmethacrylate and fumed silicas

Summary Thermomechanical properties have been investigated for the composites synthesized by the thermal polymerization of 2-hydroxyethylmethacrylate or its polymerization initiated with acrylamide complex of cobalt nitrate in the presence of the fumed silica or silicon hydride-containing silicas. The effect of the filler surface nature on temperature dependencies of deformability of the polymeric composites has been studied.     

Electron-impact fragmentation of N-substituted 2-aminobenzoxazoles and 2-aminobenzothiazoles

The mass spectra of twenty-eight N-substituted 2-aminobenzoxazoles and 2-aminobenzothiazoles have been recorded and the identity of various ions in the mass spectra have been established by high resolution measurement. The molecular compound of series, benzoxazole, undergoes loss of hydrogen cyanide and carbon monoxide from the molecular ion as the most important decomposition pathways. The mass spectra of N-substituted benzothiazoles showed a similar fragmentation as that of N-substituted benzoxazoles.     

Copolymerizations of N-arylmaleamic acids with styrene and butadiene

N-(3-Dimethylamino-6-methylphenyl)maleamic (I) and N-(2,4,6-trimethylphenyl)maleamic (II) acids were prepared; their radical copolymerizations with styrene and butadiene were investigated. The monomer reactivity ratios were determined and the Alfrey-Price copolymerization constants (e, Q) were calculated. The ratio of the average kinetic chain length to the number-average degree of polymerization indicates pronounced chain transfer to I and II. Inhibitors of radical polymerization stopped the copolymerizations of I and II with styrene but not those with butadiene.     

Reaction of vinylpyridines and vinylquinolines with 1,3,5-triazine in polyphosphoric acid

Russian Journal of Organic Chemistry -     

Characteristics of Heterophase Graft Copolymerizations

Abstract

Persulfate-initiated graft copolymerizations of glutaraldehyde crosslinked gelatin with acrylic acid, acrylamide, vinyl acetate, and methyl methacrylate in the aqueous phase were investigated. It was observed that percentage grafting, molecular weights of the grafts, and grafting efficiencies were greatly influenced by the nature of the monomers. Hydrophilic monomers gave a higher frequency of grafting but lower molecular weights. While the frequency of grafting with hydrophobic monomers was low, the molecular weights of the grafts were comparatively high. The results are explained in terms of microdomain kinetics, similar to those encountered in emulsion or suspension polymerizations.     

Synthesis of N-substituted aziridine-2-carboxylates

The synthesis of the methyl esters of N-methoxycarbonyl- and N-benzyloxycarbonylaziridine-2-carboxylic acid 2 by reacting methyl 2-chloro-N-carbalkoxyglycinate 1 with diazomethane is described. The aziridines were readily converted to derivatives of O-methylserine 5 and S-methylcysteine 6.     

Free-Radical Copolymerizations of N-Phenyl Maleimide

Free radical-initiated copolymerization of N-phenyl maleimide (NPMI) with styrene (St), vinyl acetate (VAc) and methyl meth-acrylate (MMA) at 35°C in benzene solution initiated by AIBN was studied. The copolymerization of NPMI and St yields a “nearly equimolecular” alternating copolymer, irrespective of monomer feed. Reactivity ratios of NPMI with St, VAc, and MMA were determined by a curve-fitting method which has the advantage of delivering values not involving personal judgement. Q₁ and e₁ values of NPMI were also calculated. Tentative explanations have been proposed to Interpret the “nearly alternating” copolymerization between NPMI and St. In addition, thermal stabilities of copolymers were studied by using a programmed thermo-gravimetric analysis technique. Copolymers of St, VAc, and MMA show a considerable increase in thermal stability with increasing content of NPMI. The glass transition temperatures of copolymers of NPMI with MMA and St were measured by differential scanning calorimetry. In both series of copolymers the glass transition temperature increases markedly with increasing in NPMI content. In the case of NPMI-St copolymers, the relative thermal stability as well as glass transition temperature also corroborated the nearly alternating behavior observed.     

Some N-substituted 2-amino- and 2-methylquinoline-3,4-dicarboximides

The reaction of sodium 2-amino-3-cyanoquinoline-4-carboxylate and 2-methyl-3-cyanoquino-line-4-carboxylic acid in polyphosphoric acid led to 2-amino- and 2-methylquinoline-3,4-dicar-boximide, respectively. Both of these compounds undergo imide N-alkylation reactions with methyl iodide and various chloroalkylaminodialkyl amines, while the latter also condenses with 3,4-dichlorobenzaldehyde to form styryl derivatives. Although some of these compounds may be considered structural analogs of the antimalarial 4-quinolinemethanols, none exhibited antimalarial activity.     

Thermal degradation of partly complexed poly(vinylpyridines) with transition metal chloride

The thermal degradation of poly(vinylpyridines), partly complexed with transition metal chlorides containing Co(II), Ni(II), Cu(II) and Zn(II) ions, was investigated using thermogravimetry, infrared spectrometry and gc/mass spectrometry. When poly(2-vinylpyridine) and poly(4-vinylpyridine) were partly complexed with transition metal ions, thermal degradation was initiated at low temperature. The complexes were decomposed even near the threshold temperature for weight loss. Degradations were modified by the complexation, particularly for poly(2-vinylpyridine). Yields of dimers, ethylpyridine, etc., increased linearly with degree of complexation, but that of monomer decreased linearly. The increase of the yield of dimer could be explained from the concept that polymer radicals reacted with metal chlorides, then dehydrochlorinated and underwent β-scission.