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  • 1
    Electronic Resource
    Electronic Resource
    Asymmetric halogenation and hydrohalogenation of styrene in crystalline cyclodextrin complexes (1987)
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 5 (1987), S. 449-458 
    Details
    ISSN: 1573-1111
    Keywords: Asymmetric halogenation ; hydrohalogenation ; styrene ; cyclodextrincomplex
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Asymmetric halogenation and hydrohalogenation of styrene in microcrystalline cyclodextrin complexes were studied in the gas-solid state, and compared with the homogenous reactions in aqueous or dimethyl sulfoxide solutions. The gas-solid brominations in the α- and β-cyclodextrin complexes produced predominantly (−)-1,2-dibromo-l-phenylethane. The chiral induction for the reaction of the α-cyclodextrin complex rose to 9 times that of the β-cyclodextrin complex. Brominations in the homogenous solutions containing the α- or β-cyclodextrin complexes gave no dibromide but racemic bromohydrin. In the gas-solid chlorination, the α-cyclodextrin complex gave (−)-dichloride,S-(+)-2-chloro-l-phenylethanol (14% ee) and (+)-1,2,2-trichloro-l-phenylethane, and the β-cyclodextrin complex produced (+)-dichloride,S-(+)-chlorohydrin (8% ee) and (+)-trichloride. The chiral induction of the gas-solid halogenation using the solid cyclodextrin complexes is attributed to the ability to hold rigidly a chiral conformation of the crystalline state. However, the gas-solid hydrohalogenation all gave racemic products.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00664102
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  • 2
    Electronic Resource
    Electronic Resource
    Effects of salts, solvents, and substituents on the reaction of cellulose with epoxy compounds (1976)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 177 (1976), S. 1301-1329 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Salzeffekte sowie Lösungsmittel- und Substitutenteneffekte bei der Reaktion von Cellulose mit Epoxyverbindungen wurden untersucht und mit Literaturangaben verglichen. Der Salzeffekt konnte hauptsächlich mit der Elektronegativität oder der Acidität des Kations sowie mit der Nucleophilie oder der Basizität des Anions beschrieben werden. Die Variation der Reaktion mit den Lösungsmitteln der Epoxyverbindungen konnte auf deren Löslichkeitsparameter zurückgeführt werden. Der Substituenteneffekt der Epoxyverbindungen bei dieser Additionsreaktion wurde mit Hilfe der modifizierten Gleichung von Taft, (logk-logk0)/σ*=(Qp-QsEs)/σ*, ermittelt. Unter dem Gesichtspunkt der neuen Ergebnisse wurde der Reaktionsmechanismus diskutiert.
    Notes: Effects of salts, solvents, and substituents on the reaction of cellulose with epoxy compounds were re-investigated and compared with the published data. The salt effect could be described mainly by the electronegativity or the acidity of the cations, and also by the nucleophilicity or the basicity of the anions. The variation of the reaction with solvents for epoxy compounds could be explained by the solubility parameter of the solvents. The substituent effect of the epoxy compounds on this addition reaction was elucidated by the modified Taft's equation, (logk-logk0)/σ*=(Qp-QsEs)/σ*. The mechanism for the reaction was discussed in the light of the reinvestigated phenomena.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1976.021770507
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  • 3
    Electronic Resource
    Electronic Resource
    Self-crosslinkable polymers, 2Part 1: cf.1.. High pressure copolymerization of 2,3-epoxy-1-propyl methacrylate with 2-vinyl-5-ethylpyridine (1976)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 177 (1976), S. 3265-3283 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die durch AIBN initiierte Copolymerisation von 2,3-Epoxy-1-propylmethacrylat (1) (M1) und 5-Äthyl-2-vinylpyridine (1) (M2) wurde in THF bei 60°C unter hohem Druck (bis 15 kbar) untersucht. Unter Druck wurden lösliche, lineare Polymere erhalten, die seitenständige Epoxy- und Pyridylgruppen enthalten und die als selbsthärtende Harze verwendet werden können. Die Copolymerisationsparameter r1 und r2 nehmen mit steigendem Druck zu (angegeben ist r1, r2 sowie der Druck in kbar): 0,60, 0,64 bei 2 kbar; 0,64, 0,66 bei 4 kbar; 0,72, 0,69 bei 7 kbar; 0,78, 0,72 bei 10 kbar; 0,87, 0,76 bei 13 kbar; 0,91,0,80 bei 15 kbar. Es ist daher wahrscheinlich, daß das Aktivierungsvolumen des Kettenwachstums, Δ*p, für beide Kettenwachstumsschritte unterschiedlich ist. Die Viskositätszahlen der Copolymeren in THF bei 30°C liegen zwischen 0,26 und 1,35 ; wobei der Wert vom Polymerisationsdruck und der Copolymerenzusammensetzung abhängt. Die Copolymeren sind amorph, besitzen keinen klaren Schmelzpunkt und gehen beim weiteren Erhitzen ohne Zusati: von Härtern in vernetzte Polymere über.
    Notes: 2,2′-Azoisobutyronitrile-initiated copolymerization of 2,3-epoxy-1-propyl methacrylate (1) (M1) with 5-ethyl-2-vinyl-pyridine (2) (M2) was studied in tetrahydrofuran at 60°C under high pressure up to 15 kbar. Under pressure, soluble linear polymers with pendant epoxy and pyridyl groups were obtained and can be used as self-curable resins. The monomer reactivity ratios, r1 and r2, became larger with increasing pressure (r1, r2, and pressure given): 0,60, 0,64 at 2 kbar; 0,64, 0,66 at 4 kbar; 0,72, 0,69 at 7 kbar; 0,78, 0,72 at 10 kbar; 0,87, 0,76 at 13 kbar; 0,91, 0,80 at 15 kbar. Therefore, the change of activation volume of the chain propagation, ΔV*p, may vary from one type of propagation step to another. The intrinsic viscosities of the copolymers were found in tetrahydrofuran at 30°C to be 0,26 to 1,35 and to be dependent upon the copolymer composition and the pressure. These copolymers were amorphous, had no clear melting points and became insoluble crosslinked polymers under heating without further addition of any curing agents.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1976.021771115
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  • 4
    Electronic Resource
    Electronic Resource
    Radical polymerizability of N-(4-anilinophenyl) acrylamide under high pressure (1977)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 178 (1977), S. 3253-3256 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1977.021781211
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  • 5
    Electronic Resource
    Electronic Resource
    Polymerization of mesomorphic monomers, 2.Part 1: ref.4. Bulk polymerization of 4-(2-vinyloxyethoxy)benzoic acid (1976)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 177 (1976), S. 3035-3048 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Ein neuer thermotroper flüssig-kristalliner Vinyläther, 4-(2-Vinyloxyäthoxy)benzoesäure (1a), wurde durch Hydrolyse des entsprechenden Methylesters 1b erhalten. Seine radikalische Polymerisation in Substanz wurde bei 130-195°C in fester, mesomorpher und isotrop-flüssiger Phase mit 2,2′-Azoisobutyronitril durchgeführt, um den Effekt der Monomerordnung auf die Polymerisationsgeschwindigkeit und die Eigenschaften des Polymers zu untersuchen. Das Auftreten mesomorpher Phasen scheint nicht von einem besonderen Effekt auf die Polymerisationsgeschwindigkeit und den Staudinger-Index begleitet zu sein. Die Geschwindigkeit nahm mit steigender Temperatur zu, d.h. mit abnehmender Ordnung oder erhöhter Beweglichkeit des Monomers. In N,N-Dimethylformamid beträgt der Staudinger-Index bei 30°C 0,06-0,10 dl g-1. Hochkristalline Polymere wurden in der festen und mesomorphen Phase erhalten. Das in der isotrop-flüssigen Phase gebildete Polymer war dagegen weniger kristallin.
    Notes: A new thermotropic liquid crystalline vinyl ether, 4-(2-vinyloxyethoxy)benzoic acid (1a), was obtained by hydrolysis of the corresponding methyl ester 1b. The radical bulk polymerization of this acid was carried out at 130-195°C in the solid, the mesomorphic, and the isotropic liquid phases with 2,2′-azoisobutyronitrile to study the effect of monomer ordering on polymerization rate and polymer properties. No significant effect on the rate of polymerization and the intrinsic viscosity of the products appeared to be associated with the existence of the mesomorphic phases. The rate increased with increasing temperature, i.e., decreasing ordering or enhanced mobility of the monomer. The intrinsic viscosity was 0,06-0,10 dl g-1 in N,N-dimethylformamide at 30°C. High crystalline polymers were obtained in the solid and the mesomorphic phases, whereas the polymer formed in the isotropic liquid phase was a less crystalline solid.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1976.021771018
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  • 6
    Electronic Resource
    Electronic Resource
    Solid-state polymerization of 1,4-bis(3-acetylaminophenyl)-1,3-butadiyne under high pressure1Presented at the American Chemical Society Fall Meeting, August 1984, Philadelphia, Pennsylvania and at the 25th High Pressure Conference, Jpn., November, 1984, Tsukuba, Japan. (1986)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Letters Edition 24 (1986), S. 177-184 
    Details
    ISSN: 0887-6258
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1986.140240406
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  • 7
    Electronic Resource
    Electronic Resource
    Addition reaction of multifunctional epoxides with silk fibroin (1972)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 152 (1972), S. 217-231 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die Reaktion von di- und trifunktionellen Epoxiden mit Seidenfibroin wurde in Gegenwart verschiedener Salze in mehreren Lösungsmitteln bei 45 bis 75°C untersucht. Die Reaktionsgeschwindigkeiten hängen von der Art der verwendeten Salze und Lösungsmittel ab. Große Gewichtszunahmen (bis zu 28%) wurden bei der Reaktion mit Äthylenglykol-diglycidäther, Glycerin-triglycidäther und Vinylcyclohexan-dioxid in Lösungsmitteln wie Tetrachlorkohlenstoff, Toluol, Äthanol und Isopropanol erhalten, wenn mit Thiosulfat-, Rhodanid-, Cyanid- oder Chlorionen katalysiert wurde. Die Gewichtszunahmen bei der Seide/Epoxid-Reaktion wurden hauptsächlich durch Reaktion des Epoxids mit der phenolischen Hydroxylgruppe der Tyrosinreste erhalten, wobei auch Lysin-, Histidin-, Arginin- und Serinreste reagieren. Die Seide besaß nach der Reaktion mit den Epoxiden geringe Löslichkeit in wäßriger NaOH und HCl ohne Abnahme der Feuchtigkeitsaufnahme und Biegsamkeit und hatte stark verbesserte Knitterfestigkeit.
    Notes: The reaction of di- and tri-functional epoxides with silk fibroin was investigated in the presence of various salts in different solvents at 45-75°C. The reaction rates depend on the nature of the salts and the solvents used. Large weight gains (to 28%) were obtained in the reactions with ethyleneglycol diglycidyl ether, glycerol triglycidyl ether, and vinylcyclohexene dioxide catalyzed by thiosulfate, thiocyanate, cyanide, or chloride ions in such solvents as carbon tetrachloride, toluene, ethanol, and isopropanol. The weight gains in the silk/epoxide reaction were obtained mainly by the reaction of epoxide with the phenolic hydroxyl groups of the tyrosine residues, although lysine, histidine, arginine, and serine residues were found to react. The silk fabrics reacted with the epoxides were imparted with low solubilities in aqueous NaOH and HCl solutions without an appreciable decrease of moisture regain and flexibility of the fabric, and had much improved creaseproof properties.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1972.021520121
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  • 8
    Electronic Resource
    Electronic Resource
    13C- and 1H-nmr evidence for all-cis peptide bonds in cyclic tetrapeptide cyclo(L-Pro-Sar)2 (1983)
    New York : Wiley-Blackwell
    Biopolymers 22 (1983), S. 617-632 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Conformations of the cyclic tetrapeptide cyclo(L-Pro-Sar)2 in solution were studied by 1H- and 13C-nmr spectrometry and model building. The nmr data provide definite evidence that this cyclic peptide exists chiefly in two conformations, namely, a C2-symmetric conformation and an asymmetric structure. The former was demonstrated to be predominant in polar solvents (100% in Me2SO-d6). This structure contains all cis-peptide bond linkages and all trans′ Pro Cα=CO bonds. It represents the first cyclic tetrapeptide in which all four peptide bonds have been found in the cis-conformation. As the polarity of the solvent decreases, the population of C2-symmetric conformers decreases (88% in CD3CN and 65% in CDCl3). At the same time, a minor asymmetric conformer, characterized by cis-cis-cis-trans peptide bond sequences (two cis Sar-Pro bonds, one cis Pro-Sar bond, and one trans Pro-Sar bond), is seen to increase (9% in CD3CN and 30% in CDCl3). A proposed predominant conformation in solution for cyclo(L-Pro-Sar)2 was compared with a crystal structure, as reported in an accompanying paper. Both structures show striking overall similarities.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.360220207
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  • 9
    Electronic Resource
    Electronic Resource
    Salt-catalyzed addition reaction of epoxy compounds with various silk fibroins (1977)
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 64 (1977), S. 1-18 
    Details
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die heterogene Addition Zahlreicher Monoepoxyverbindungen an einigen Arten von Seidenfibroinen, wiez. B. aus Diethyoploca japonica, Antheraeapernyi, Philosamia cynthia ricini und Bombyx mori wurde in verschiedenen Lösungsmitteln bei 45-75°C unter Verwendung Zahlricher wäßriger Salzlösungen als Katalysatoren untersucht. Die auftretenden Salzeffekte werden hauptsächlich der Katalysatoren untersucht. Die auftretenden Salzeffekte werden hauptsächlich der Nucleophilie der Anionen und der Acidität der Kationen zugeschrieben. Substituenteneffekte der Epoxyverbindungen auf die Additionsreaktionen wurden mit Hilfe der modifizierten Taft-Gleichung untersucht.
    Notes: The heterogeneous addition reaction of various monoepoxy compounds with some kinds of silk fibroins e.g. of Dictyoploca japonica, Antheraea pernyi, Philosamia cynthia ricini and Bombyx mori was investigated in various solvents at 45-75°C using aqueous solutions of many kinds of salts as padding catalysts. The salt effects on these reactions of silk fibroins with epoxy compounds were described mainly by the nucleophilicity of the anions and also by the acidity of the cations. The substituent effects of the epoxy compounds on the addition reactions were elucidated by the modified Taft's equation. By means of the solubility parameter of the solvents we were able to explain the solvent dependency of the weight gains of the silk fibroins. The reactivity difference among these silk fibroins was partly described by the variation of shape and the amino acid compositions of the fibers.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/apmc.1977.050640101
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  • 10
    Electronic Resource
    Electronic Resource
    Epoxy resins from substituted benzoic acids-formaldehyde resinsPresented at 14th Annual Meeting of Gosei Jushi Kogyo Kyokai on Thermosetting of Resins, Osaka, Sept. 1964. (1967)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 11 (1967), S. 1345-1358 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Some polybasic acid derivatives were obtained from substituted benzoic acids such as p- and o-toluic acids, and p-formaldehyde in concentrated sulfuric acid by a method similar to that of Naokawa et al. The structure of these resinous substituted benzoic acid-formaldehyde materials was determined by a paper chromatography and infrared spectrum analysis, and found to be where n = 0-2; R = H, R′, and R″ = H or CH3, respectively. New glycidyl-ester-type epoxy resins were prepared from these substituted benzoic acid-formaldehyde resins and epichlorohydrin in the presence of sodium hydroxide, using dioxane as a solvent. These resins were considered to have the general structure shown above, where n = 0-2, , and R′ and R″ = H or CH3, respectively.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1967.070110730
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