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  • 1
    Electronic Resource
    Electronic Resource
    Functional polymers, XL. Syntheses of mono- and di(4-methoxy)benzotriazolesubstituted 2,4-dihydroxyaceto(or benzo)phenones (1986)
    Springer
    Monatshefte für Chemie 117 (1986), S. 805-819 
    Details
    ISSN: 1434-4475
    Keywords: Functional polymers ; 2(2-Hydroxyphenyl)2 H-benzotriazoles ; 2-Hydroxyphenylaceto(benzo)phenones ; Azo coupling ; Reductive cyclization ; Ultraviolet stabilizers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wurden acht Benzotriazole und 4-Methoxybenzotriazole — mono- oder disubstituierte Derivate von 2,4-Dihydroxyaceto(oder benzo)phenonen — über Azokopplung von 4-Methoxy-2-nitrobenzoldiazoniumchlorid mit 2,4-Dihydroxyaceto(oder benzo)phenonen und nachfolgender reduktiver Cyclisierung synthetisiert. Reine monosubstituierte Verbindungen waren sehr schwer herzustellen. Sorgfältige Wahl despH-Wertes für die Azo-Kupplung und geeignete Reagentien für die reduktive Cyclisierung waren dabei wesentlich. Alle Verbindungen wurden mittels UV-, IR-,1H-NMR- und13C-NMR-Spektren und Elementaranalysen charakterisiert. Die synthetisierten Verbindungen besitzen jeweils eine 2-(2-Hydroxyphenyl)-2H-benzotriazol-Einheitund eine 2-Hydroxyaceto(oder benzo)phenon-Einheit im gleichen Molekül und stellen effektvolle und nützliche Ultraviolett-Absorber dar.
    Notes: Abstract Eight benzotriazoles and (4-methoxy)benzotriazoles, mono- or di-substituted derivatives of 2,4-dihydroxyaceto(or benzo)phenone were synthesized by azo coupling of (4-methoxy)2-nitrobenzenediazonium chloride with 2,4-dihydroxyaceto(or benzo)phenone followed by reductive cyclization. Pure mono-substituted compounds were very difficult to prepare. Careful selection of thepH for the azo coupling and selection of the proper reagents for the reductive cyclization were essential. All compounds were characterized by their ultraviolet, infrared1H and13C NMR spectra and their elemental analysis. These compounds have both the 2(2-hydroxyphenyl)2H-benzotriazole unit and a 2-hydroxyaceto(or benzo)phenone unit in the same molecule and are effective and useful ultraviolet absorbers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00810072
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  • 2
    Electronic Resource
    Electronic Resource
    Functional polymers, 11Part 10: W. Deits, E. Westhead, O. Vogl, J. Macromol. Sci., Chem. 16, 691 (1981). Synthesis and polymerization of 2-(2-hydroxy-5-vinylphenyl)-2 H-benzotriazoleDedicated to Prof. Dr. Georg Manecke on the occasion of his 65th birthday, with warmest personal wishes (1982)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 183 (1982), S. 259-279 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: 2-(2-Hydroxy-5-vinylphenyl)-2H-benzotriazole (9) was prepared by a seven step synthesis in about a 25% overall yield starting from o-nitroaniline. Diazotization in aqueous HCl gave a diazonium salt which was coupled with p-ethylphenol to an azo-dye which was reduced with zinc powder in sodium hydroxide solution to 2-(2-hydroxy-5-ethylphenyl)-2H-benzotriazole (4). This compound was acetylated and then brominated with N-bromosuccinimide to 2-[2-acetoxy-5-(1-bromoethyl)phenyl]-2H-benzotriazole (6) which was dehydrobrominated with triethylamine in acetonitrile or tributylamine in dimethylacetamide to the vinyl compound which was hydrolyzed to 9. This monomer was readily homopolymerized and copolymerized with styrene and methyl methacrylate using 2,2′-azobis(2-methylpropionitrile) as initiator.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1982.021830201
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  • 3
    Electronic Resource
    Electronic Resource
    Kinetic determination of stereoselectivity in the anionic polymerization of α-ethyl-α-phenyl-β-propiolactone (1983)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 184 (1983), S. 811-819 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The kinetics of the anionic polymerization of optically active α-ethyl-α-phenyl-β-propiolactone (optical purity 16,8%) initiated with bis(triphenylphosphine)iminium acetate was investigated and the rate constants for the homo-(kph) and crosspropagation (kpc) (considering R and S enantiomers as comonomers) were determined. The knowledge of the values of kph and kpc, equal to 1,53·10-4 and 9,0·10-51· mol-1·s-1, respectively (25°C, CH2Cl2 solvent), allowed us to calculate the distribution of homosequences in the polymer prepared from racemic monomer. The concentration of homosequences was slightly higher than calculated for the process with random enchainment of enantiomers. Thus, the content of homodyads, homotriads, and homotetrads equals 63, 40, and 25%, whereas for the random process it was 50, 25, and 13%, respectively. This difference is, however, too small to create homoblocks which could be responsible for the observed crystallinity of these polymers.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1983.021840415
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  • 4
    Electronic Resource
    Electronic Resource
    Haloaldehyde polymers, 34Part 33: cf. J. Zhang, G. D. Jaycox, O. Vogl, Polym. J. 19, 603 (1987).. 1H and 13C NMR spectra of chloral oligomers prepared by lithium tert-butoxide initiation and the assignment of the meso/racemo addition products of the dimers (1989)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 190 (1989), S. 2217-2228 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: 1H and 13C NMR spectra of the mixture of chloral oligomers prepared by initiation with lithium tert-butoxide were examined in detail. 1H and 13C NMR signals due to meso and racemo diastereomers of the dimer fraction were unequivocally assigned through the 13C-1H COSY spectrum and the 13C NMR spectra with low-power selective 1H-decoupling. The two-dimensional NOESY spectrum showed correlation peaks between the signals due to the methine (acetal) protons of the neighbouring chloral monomeric units of the most abundant isomers in the trimer and tetramer fractions. The 1H NOE enhancements and 3JCH coupling constants were measured for the dimers; the results confirmed the meso/racemo assignments based on earlier conformational analysis.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1989.021900922
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  • 5
    Electronic Resource
    Electronic Resource
    Cationic polymerization of aldehydes (1974)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 175 (1974), S. 1281-1308 
    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 kationische Polymerisation von Formaldehyd, höheren aliphatischen Aldehyden und Halogenaldehyden wird diskutiert. Die Polymerisation wird mit Lewis-Säuren und Brønsted-Säuren initiiert, wird aber beherrscht von der Tatsache, daß in fast allen Fällen die Polymeren ausfallen und aus der Lösung auskristallisieren. Die Folge ist, daß die Polymerisationen diffusionskontrolliert werden und dies in einigen Fällen sogar bei kleinen Umsätzen. Diese Erscheinung ist nicht auf die kationische Polymerisation beschränkt, doch kommt hier hinzu, daß die wachsenden Enden leicht okkludiert werden und kationische Initiatoren von dem ausfallenden Polymeren absorbiert werden. Die Morphologie und das Ausmaß der Quellung des ausgefallenen Polymeren spielt eine wichtige Rolle in bezug auf die Polymerisationsgeschwindigkeit und den Umsatz des Monomeren zum Polymeren. Wie zu erwarten, lassen sich aliphatische Aldehyde leichter als Halogenaldehyde mit kationischen Initiatoren polymerisieren; dies kann in dem Unterschied des Startmechanismus begründet sein.
    Notes: Cationic polymerizations of formaldehyde, higher aliphatic aldehydes and haloaldehydes are discussed. The polymerization is initiated by Lewis and Brønsted acids but is dominated by the fact that in almost all cases the polymers precipitate and crystallize from the solution. As a consequence the polymerizations become diffusion controlled sometimes even at low conversions. This phenomenon is not limited to cationic polymerization but additionally the growing ends are readily occluded and cationic initiators are adsorbed on the precipitated polymer. The morphology and the degree of swelling of the precipitated polymer plays an important role upon the rate of polymerization and conversion of monomer to polymer. As expected, polymerizations of aliphatic aldehydes are more readily carried out by cationic initiators than the polymerization of haloaldehydes; this may be caused by the difference in the initiation mechanism.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1974.021750413
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  • 6
    Electronic Resource
    Electronic Resource
    Head-to-head polymers, 14Part 13: cf.18. Part 15: F. Laupretre, L. Monnerie, O. Vogl, Eur. Polym. J., in press.. Thermal degradation of head-to-head and head-to-tail polystyrenes and poly(vinylcyclohexane)s (1979)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 180 (1979), S. 2295-2302 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The thermal degradation behavior of head-to-head (H-H) and head-to-tail (H-T) polystyrenes and poly(vinylcyclohexane)s has been investigated by direct pyrolysis in a mass spectrometer. Both H-H and H-T isomers show only small differences in their initial temperatures of decomposition but remarkably different degradation processes. Whereas H-T polystyrene decomposes in accordance with earlier investigations mainly by a radicalic depolymerization into the monomer and yields only a small amount of dimer and trimer, the H-H polystyrene shows no unzipping and only a statistic degradation into oligomeric styrenes. The formation of stilbene is a diagnostic reaction of H-H polystyrene. The pyrolysis-mass spectra of H-H and H-T poly(vinylcyclohexane)s are more similar than those of the polystyrenes but the favored thermal cleavage between the two tertiary carbon atoms or next to the tertiary carbon atoms of the polymer backbone chain leads to some characteristic fragments, e.g. 1,3-dicyclohexylpropene from the H-T and 1,2-dicyclohexylethane from the H-H polymer.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1979.021801003
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  • 7
    Electronic Resource
    Electronic Resource
    Haloaldehyde polymers, 40Part 39, cf.15a.. Stereostructure of chloral oligomers prepared with lithium tert-butoxide: Helical conformation of the linear isotactic oligomers in crystal and in solution (1990)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 191 (1990), S. 557-569 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The stereostructures of linear chloral oligomers were determined by X-ray single crystal analysis. The chloral oligomers from dimer to pentamer were isolated by distillation and by GPC fractionation from the oligomer mixture prepared with t-BuOLi initiation and acetate endcapping. The dimer fraction was a diastereomeric mixture of the racemo (1) and meso (2) isomers, while the trimer, tetramer and pentamer fractions each contained a single diastereomer (3, 4 and 5). The single crystals of 2, 3, 4 and 5 grown from methanol solutions belong to the space groups P1-, P21/n, P21/a and Pca21, respectively. X-ray analyses showed that the acetal backbones of 2, 3 and 4 consist exclusively of meso dyads. The backbone arrangements of 2, 3 and 4, are essentially identical and approximate the repeat gauche(+)-skew(-) sequences from the t-BuO group to the acetyl terminal group (for S-configurations). The conformation of (S,S,S,S)-4 is very similar to a unit sequence of a 4/1-helical structure of isotactic polychloral with left-handed helicity. The axis of the helix is parallel to the c-axis of the crystal, and the repeat distance is 4,81 Å. The conformations of the acetal backbones of 4 and 5 in solution were also investigated by NMR spectroscopy, on the basis of dihedral angle dependence of 3JC—O—C—H coupling constants.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1990.021910311
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  • 8
    Electronic Resource
    Electronic Resource
    Haloaldehyde polymers, 43.Part 42, cf. G. D. Jaycox, O. Vogl, J. Am. Chem. Soc., submitted.. Structure of 2-bornyloxy-terminated chloral oligomers (1991)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 192 (1991), S. 35-48 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Oligomerization of trichloroacetaldehyde (chloral) was carried out with the lithium salt of (1 S, 2 R, 4 S)-(-)-borneol as the initiator. The unimer and dimer fractions consisted of two and four diastereomers, respectively; the individual isomers were isolated from the fractions by crystallization from methanol or by high performance liquid chromatography. The X-ray single-crystal analysis showed that the major isomer in the unimer fraction is the (R)-form which has the acetal carbon in (R)-configuration. The diastereomeric ratios were determined by 1H NMR as R/S = 57/43 for the unimers and RS/SR/RR/SS = 34/25/23/18 for the dimers. The conformations of the meso-dimers [(R,R)- and (S,S)-isomers] in the crystalline form corresponded to a half turn of the 41-helix of isotactic polychloral, whereas the conformations of the racemo-dimers (the (R,S)- and (S,R)-isomers) were different from the helical structure in the crystal and in solution. The trimer fraction consisted of six of the eight possible diastereomers; among these isomers, the mm isomers (the (R,R,R)- and (S,S,S)-isomers) were highly predominant. The amount of the (R,R,R)-trimer formed was only slightly larger than that of the (S,S,S)-isomer. (a) Part 42, cf. G. D. Jaycox, O. Vogl, J. Am. Chem. Soc., submitted.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1991.021920104
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  • 9
    Electronic Resource
    Electronic Resource
    Haloaldehyde polymers, 15.Part 14: L. S. Corley, O. Vogl, J. Macromol. Sci., Chem. 14, 1105 (1980). Stabilization of polychloral by posttreatment (1980)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 181 (1980), S. 2111-2126 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Polychloral prepared by anionic polymerization has primarily alkoxide endgroups as the living terminal ends. The initial endgroups depend on the type of nucleophile used for the initiation. Alkoxide-terminated polychloral degrades to monomer on heating to slightly above 100°C or on extraction with methanol or acetone. Programmed DTG shows a degradation rate maximum (MDT) near 150°C. Terminations of the polymer endgroups were observed when the polymer was allowed to stand for long periods of time before workup. The type and amount of stabilization depends on the cation and residual monomer. With HCI the alkoxide ends can be protonated to give hydroxyl terminated polychloral, which is stable to extraction and has an MDT of 220°C. Acylation or alkylation as posttreatments could not be shown to produce the expected acyl- or alkyl endcapped polychloral, but posttreatment with acetyl chloride produced partially stable polymer (one MDT higher than 300°C) without detectable acetyl endgroups. The most effective posttreatment is with PCl5/CCl4 which gives highly stabilized polychloral with an MDT near 350°C. The treatment was only effective in thin sections of polymer and appeared to have introduced a chlorine endgroup.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1980.021811009
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  • 10
    Electronic Resource
    Electronic Resource
    Functional polymers, 5.Part 4: D. Tirrell, D. Bailey, C. Pinazzi, O. Vogl, Macromolecules 11, 313 (1978). Preparation and polymerization of methyl 4-vinylsalicylate, 4-vinylsalicylic acid and 4-vinylacetylsalicylic acid (1980)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 181 (1980), S. 2097-2109 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Methyl 4-vinylsalicylate, 4-vinylsalicylic acid, and 4-vinylacetylsalicylic acid were prepared in overall yields of 28%, 21% and 16%, respectively, starting with 3-ethylphenol. Radical polymerization of all three monomers was investigated. Methyl 4-vinylsalicylate and 4-vinylsalicylic acid polymerized normally via radical initiation, giving soluble polymers of high molecular weight. 4-Vinylacetylsalicylic acid gave gelled polymerization mixtures in tert-butanol and in dimethyl sulfoxide, using the same experimental procedure; this was shown to be a result of intermolecular transesterification during polymerization. A water-insoluble copper complex of poly(4-vinylsalicylic acid) was prepared. Methyl 4-vinylacetylsalicylate was also synthesized, in 35% yield, but no polymerization experiments were performed with this monomer. These new polymeric salicylic acid derivatives are of interest as ultraviolet stabilizers, as protective agents for the skin, as metal-complexing agents, and as potential medicinal agents.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1980.021811008
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