Synthesis of deuterium and tritium labelled phenyl glycine

A new method of synthesis of phenyl glycine labelled with deuterium and tritium was elaborated. Labelled phenyl glycine was obtained by isotope exchange method between phenyl glycine and deuterated or tritiated water at elevated temperature in hydrochloric acid medium using K₂PtCl₄ as a catalyst. 37 GBq /1 Ci/ HTO was used for the synthesis of tritiated phenyl glycine and labelled product with specific activity of 185 MBq/mole /5 mCi/mole/ was obtained.     

Synthesis of aminimide monomers and polymers

A convenient and practical synthesis of trimethylamine acrylimide, 1 , starting from 1, 1, 1-trimethylhydrazinium p-toluenesulfonate, 3 , and 3-chloropropionyl chloride is described. The intermediate, trimethylamine 3-chloropropionimide, 2 , is easily transformed into 1 either through a single-step dehydrohalogenation or through a two-step process consisting of very facile thermal rearrangement to 1,1,1-trimethylacrylylhydrazinium chloride, 4 , and subsequent deprotonation. Two new polymerizable monomers, 5 , and 6 , containing aminimide functionality were synthesized from trimethylamine imine, 7 , and the appropriate vinyl oxazolones, 8 , and 9 . Synthesis of hitherto unreported trimethylamine chloroacetimide, 10 , which offers unique opportunities for incorporating water-solubilizing and alkali-stable aminimide functionality into a variety of structures through nucleophilic displacement, is also described.     

Synthesis of tritium labelled methyl vinyl ketone and its use in copolymer analysis

The synthesis of tritiated methyl vinyl ketone by base catalysed exchange and its use in determining the ketone content of styrene/methyl vinyl ketone copolymers are reported. Methods of assay are described in detail and the general applicability of the method is discussed.     

Synthesis of sulfone-containing monomers and polymers using cationic cyclopentadienyliron complexes

The synthesis of sulfone-containing monomers with pendent cationic cyclopentadienyliron (CpFe⁺) moieties has been accomplished via nucleophilic aromatic substitution of dichloroarene complexes with a number aliphatic dithiols. These complexes were further oxidized using m-CPBA to give the sulfone-based monomers. Polymerization of the sulfone-based monomers with O-containing nucleophiles produced the sulfone-based polymers. Direct nucleophilic aromatic substitution of dichloroarene complexes with dinucleophiles allowed for the formation of organoiron sulfide-based polymers. Oxidation of these polymers led to the formation of sulfone polymers with the pendent iron moieties. The organometallic monomers and polymers were found to be more soluble in polar solvents in comparison to their organic analogues.     

Synthesis of photo and thermosetting monomers and polymers based on benzocyclobutene

Russian Chemical Bulletin - Modern approaches to the preparation of monomers and polymers based on benzocyclobutene are considered. The groups of polymers containing siloxane, silyl,...     

Synthesis of homologous monomers and polymers of carbazole,phenothiazine and dibenzazepine

Monomers and polymers of 3-vinyl-N-ethylcarbazole, 3-vinyl-N-methylphenothiazine, 3,7-divinyl-N-methylphenothiazine, N-acrylylcarbazole, N-acrylylphenothiazine, and N-acrylyl- and N-methacrylyldibenzazepine have been synthesized. The synthetic procedures for preparing the monomers and polymers are described.     

Synthesis and characterization of monomers and polymers for adhesives from methyl oleate

The focus of this work is to synthesize a monomer from a fatty acid methyl ester capable of forming high molecular weight polymers. The mono‐unsaturation in the starting material, methyl oleate, was first epoxidized using a peroxy acid. This intermediate material was further modified using acrylic acid. The acrylated molecule is able to participate in free‐radical polymerization reactions to form high molecular weight polymers. The rate of polymerization was low because of the long aliphatic structure of the monomer. It is hypothesized that the polymerization reaction occurred in the interface between the particle and water, thereby slowing down the reaction. After 18 h of reaction, a monomer conversion of approximately 91% was achieved. A maximum weight‐average molecular weight of approximately 10⁶ g/mol was observed after 14 h of reaction. At early reaction times linear polymers were formed. However, as the reaction time increased, the amount of branching that occurred on the polymer molecule increased, as indicated by gel permeation chromatography and light scattering. This has been attributed to chain transfer to polymer via hydrogen abstraction from a tertiary backbone C–H bond. The resulting polymer may be of considerable interest for pressure‐sensitive adhesive applications. © 2002 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 451–458, 2002; DOI 10.1002/pola.10130     

TNT-Based condensation monomers and polymers

New aromatic diamines were obtained on the basis of available and inexpensive 2, 4, 6-trinitrotoluene (trotyl, TNT). Monomers obtained were used for the preparation of the new organo-soluble polyimides containing thiophenoxy and phenoxy side groups.     

Vinyl monomers bearing chromophore moieties and their polymers. III. Synthesis and photochemical behavior of acrylic monomers having phenothiazine moieties and their polymers

Four acrylic monomers bearing phenothiazine moieties, i.e., N-acrylyl-phenothiazine (APT), N-acrylyl-2-chlorophenothiazine (ACPT), N-acrylyl-2-acetylphenothiazine (AAPT), and 10-acrylyl-1-azaphenothiazine (AAzPT) were synthesized by dehydrohalogenation of the corresponding N-(β-chloropropionyl)-substituted phenothiazine derivatives with 1,8-diazabicyclo[5.4.0]undec-5-ene (DBU). These monomers could easily be polymerized by initiation with AIBN. The emission fluorescence spectra of the monomers and their polymers were recorded, which showed that the polymers displayed much stronger fluorescence than their corresponding monomers at the same chromophore concentrations. This phenomenon, as termed as “structural self-quenching effect,” was commonly observed for acrylic monomers bearing chromophore moieties and ascribed to the coexistence of the electron-donating chromophore and the electron-accepting double bond in the same molecule. Because of the formation of exciplex, the monomer APT, as well as ACPT, AAPT, AAzPT, and their polymers, could initiate the photopolymerization of AN. The charge transfer phenomenon between P(APT), P(ACPT), and C₆₀ was also explored. © 1996 John Wiley & Sons, Inc.     

New carbazole-containing monomers and polymers

Five novel vinyl monomers, all of which contain 3-substituted carbazolyl groups [i.e., N-(9-ethyl-3-carbazolyl)-maleimide, 9-ethyl-3-carbazolyl acrylamide, 9-ethyl-3-carbazolyl methacrylamide, 9-ethyl-3-hydroxymethylcarbazolyl acrylate, and 9-ethyl-3-hydroxymethylcarbazolyl methacrylate], and their corresponding polymers were synthesized. Two methods were used for the synthesis of the last two monomers.     

Synthesis, structure and mesomorphism of new cholesteric monomers and smectic comblike polymers

Seven new cholesteric monomers (M-1−M-7) and the corresponding smectic comblike polymers containing cholesteryl groups (P-1−P-7) were synthesized. The chemical structures and purity were characterized by FT-IR, ¹H NMR, and elemental analyses. The specific optical rotations were evaluated with a polarimeter. The mesomorphism was investigated by polarizing optical microscopy, differential scanning calorimetry, thermogravimetric analysis, and X-ray diffraction. The specific optical rotation values of these monomers and polymers with the same numbers of phenyl ring and terminal groups were nearly equal, however, they decreased with increasing the aryl numbers in the mesogenic core. M-1−M-7 showed oily streak texture and focal conic texture, or fingerprint texture, or spiral texture of cholesteric phase. P-1−P-7 showed the smectic A phase. The melting, clearing, and glass transition temperatures increased, and the mesophase temperature ranges widened with increasing the aryl number in the mesogenic core. Surprisingly, although the molecular structures of M-6 and M-7 were similar to those of M-4, namely the mesogenic cores contained three phenyl rings, their phase behavior had a considerable difference, and T_m and T_i of M-6 and M-7 were less than those of M-4. In addition, M-6 and M-7 also showed an obvious glass transition. TGA showed that all the polymers had good thermal stabilities.     

Synthesis and properties of reactive liquid crystal monomers and side-chain liquid crystalline polymers

Two nematic liquid crystal (LC) monomers containing double bonds in the side chain were designed and synthesised. Length of the side groups varied from 1 to 2 methylene units. The side-chain polymers were synthesised by hydrosilylation reaction. The molecular structures of the intermediates and the LC monomers were characterised by Fourier transform infrared, elemental analysis and nuclear magnetic resonance spectroscopy. The thermal phase behaviour of the monomers and polymers were investigated by differential scanning calorimetry and polar optical microscopy coupled with hot stage. The LC monomers showed only one nematic mesophase in the cooling process. And, the two polymers exhibit an enantiotroppic nematic mesophase either in the heating or in the cooling process.     

Synthesis and characterization of new cholesteric monomers and smectic polymers containing menthyl groups

New cholesteric monomers (M₂−M₅) and the corresponding smectic homopolymers (P₂−P₅) based on menthyl groups were synthesized. The chemical structures were characterized by Fourier transform infrared and ¹H NMR. The specific optical rotations were evaluated with a polarimeter. The structure–property relationships of the new compounds are discussed. The mesomorphism was investigated by differential scanning calorimetry, thermogravimetric analysis, polarizing optical microscopy, and X-ray diffraction. The selective reflection property of light was studied with UV/Visible/NIR. The monomers M₂−M₅ formed the cholesteric or blue phase when a flexible link chain was inserted between the mesogenic core and the terminal menthyl groups by reducing the steric effect. M₁ showed no mesomorphism, while M₂−M₅ revealed enantiotropic cholesteric phase. In addition, M₂ and M₃ also showed a cubic blue phase on cooling. The selective reflection of light for M₂−M₅ shifted to the short reciprocal wavelength region with increasing the temperature or intramolecular spacer length. P₂−P₅ exhibited the smectic A phase. The melting, clearing, and glass transition temperatures increased when increasing the aryl number in the mesogenic core or decreasing the intramolecular spacer length.     

Vinyl monomers bearing chromophore moieties and their polymers. XI. Synthesis and photochemical behavior of carbazole‐containing methacrylic monomers and their polymers

Three carbazole‐containing methacrylic monomers, 2‐(N‐carbazolyl)ethyl methacrylate(CzEMA), 6‐(N‐carbazolyl)hexyl methacrylate(CzHMA), and 11‐(N‐carbazolyl)undecyl methacrylate (CzUMA), and their saturated model compounds, 2‐(N‐carbazolyl)ethyl isobutyrate, 6‐(N‐carbazolyl)hexyl isobutyrate, and 11‐(N‐carbazolyl)undecyl isobutyrate, were synthesized and polymerized. UV absorption spectra showed that there was either negligible or no interaction between the carbon–carbon double bond of the methacrylic group and the carbazolyl chromophore moiety in the ground state for these monomers. Fluorescence spectra of the monomers, their model compounds, and the polymers were recorded in the solvents with different polarities. CzEMA exhibited the fluorescence structural self‐quenching effect (SSQE), but CzHMA and CzUMA did not. In addition, the SSQE of CzEMA depended strongly on the polarity of the solvents. That is, the stronger the polarity of a solvent was, the more obvious the SSQE was. Therefore, the SSQE of CzEMA mainly was caused by the intramolecular charge‐transfer interaction between the excited electron‐donating carbazolyl chromophore moiety and the electron‐accepting carbon–carbon double bond of the methacrylic group. This was confirmed by the fluorescence‐decay curves and the fluorescence lifetimes of the monomers, their model compounds, and the polymers. The monomers, their model compounds, and the polymers initiated the photopolymerization of methyl methacrylate (MMA) upon UV irradiation. CzEMA showed greater initiation ability than the other two monomers and their model compounds; this was ascribed to the photoinduced intramolecular charge‐transfer interaction. The higher initiation efficiency of the homopolymers compared to that of the copolymers with MMA was interpreted as the result of singlet energy migration of the excited carbazolyl chromophores along the polymer chains. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 679–688, 2000     

Synthesis and characterization of alkylated N‐vinylformamide monomers and their polymers

N‐alkyl‐N‐vinylformamide monomers (alkyl: n‐butyl, hexyl, decyl, and dodecyl) are synthesized in two steps: first, preparation of N‐vinylformamide potassium salt by the reaction of N‐vinylformamide (NVF) with potassium t‐butoxide, then reaction with alkyl bromide. All four monomers are liquid and are characterized by IR, ¹H NMR, ¹³C NMR, and mass spectra. They exist as rotomers in solution and a 2D NOE experiment on the N‐hexyl containing polymer shows the E isomer to be favored. The polymerizability of the four monomers is from good to fair, depending upon the length of alkyl chain on the N‐atom‐‐the longer the chain length, the lower lower the polymerizability of monomer. The hydrolysis of poly(N‐hexyl‐N‐vinylformamide) and poly(N‐dodecyl‐N‐vinylformamide) under acidic and basic conditions was examined. Studies show that hydrolytic cleavage of formyl groups of poly (N‐alkylated‐N‐vinylformamide) depends on the hydrophobicity of the alkyl substituent on the N‐atom under acidic conditions; both polymers were hydrolyzed to only a minor extent under alkaline conditions. The N‐alkylated monomers can copolymerize with NVF and demonstrate amphiphilic properties. The copolymers demonstrate a critical aggregation concentration above which they can solubilize a water insoluble dye; the N‐hexyl containing copolymer stabilizes a castor oil‐in‐water emulsion. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4994–5004, 2004     

Automatic isotope gas analysis of tritium labelled organic materials

An analytical procedure and an automatic apparatus are described for the determination of tritium in organic compounds by gas counting. The sample is pyrolysed in hydrogen atmosphere at 1000°C, then, with hydrogen, the decomposition products are rinsed through a column of molecular sieve-5A heated to 550°C. Tritium in water, hydrogen sulphide, ammonia and hydrogen cyanide is transferred into the hydrogen stream by isotope exchange completed on the column. The inactive water vapor, hydrogen sulphide, ammonia and hydrogen cyanide as well as carbon dioxide are removed from the gas stream by appropriate absorbents, and the radioactive hydrogen together with tritiated methane, carbon monoxide and nitrogen included in the pyrolytic products is led into an internal proportional counter tube for radioactivity measurement. The method provides quantitative recovery, it is free of memory effect and suitable for the rapid assay of a wide variety of organic compounds containing C, H, N, O, S in addition to tritium.