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  • 1
    Electronic Resource
    Electronic Resource
    Stereospecific polymerization of benzyl α-(alkoxymethyl) acrylates (1997)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 721-726 
    Details
    ISSN: 0887-624X
    Keywords: benzyl α-(alkoxymethyl)acrylate ; stereospecific polymerization ; anionic polymerization ; isotactic polymer ; tacticity ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: α-(Alkoxymethyl) acrylates, such as methyl α-(phenoxymethyl) acrylate, benzyl α-(methoxymethyl)acrylate (BMMA), benzyl α-(benzyloxymethyl)acrylate, and benzyl α-(tert-butoxymethyl)acrylate, were synthesized, and their polymerizability and the stereoregularity of the polymers obtained by radical and anionic methods were investigated. The radically obtained polymers were found to be atactic by 13C- and 1H-NMR analyses, but the polymers obtained with lithium reagents in toluene at -78°C were highly isotactic. Further, it is noteworthy that isotactic polymers were also produced with lithium reagents even in tetrahydrofuran. Effects of polymerization temperature and counter cation on stereoregularity were clearly observed in the polymerization of BMMA, and a potassium reagent afforded an almost atactic polymer. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35:721-726, 1997
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Asymmetric anionic polymerization of (2-fluorophenyl)(4-fluorophenyl)(2-pyridyl)methyl methacrylate leading to a helical polymer (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2013-2019 
    Details
    ISSN: 0887-624X
    Keywords: asymmetric polymerization ; anionic polymerization ; (2-fluorophenyl)(4-fluorophenyl)(2-pyridyl) methyl methacrylate ; optically active polymer ; helix ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A novel racemic methacrylate, (2-fluorophenyl)(4-fluorophenyl)(2-pyridyl)-methyl methacrylate1 (2F4F2PyMA), was synthesized and polymerized with chiral complexes of N,N′-diphenylethylenediamine monolithium amide (DPEDA-Li) with (-)-sparteine (Sp), (2S, 3S)-(+)-2,3-dimethoxy-1,4-bis(dimethylamino)butane (DDB), and (S)-(+)-1-(2-pyrrolidinylmethyl)pyrrolidine (PMP) in toluene at -78°C. The monomer showed higher resistance against methanolysis compared with triphenylmethyl methacrylate (TrMA) and several other analogues. In the asymmetric anionic polymerization of 2F4F2PyMA, PMP was found to be a more effective chiral ligand than DDB and Sp and gave quantitatively an optically active polymer with nearly perfect isotacticity. Enantiomer selection was observed in the polymerization of racemic 2F4F2PyMA with the chiral lithium complexes. Chiral recognition ability of the optically active poly(2F4F2PyMA) was examined by an enantioselective adsorption experiment. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2013-2019, 1998
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Helix-sense-selective polymerization of phenyl[bis(2-pyridyl)]methyl methacrylate and chiral recognition ability of the polymer (1993)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 31 (1993), S. 2721-2728 
    Details
    ISSN: 0887-624X
    Keywords: phenyl[bis(2-pyridyl)]methyl methacrylate ; optically active polymer ; solvolysis ; chiral stationary phase ; anionic polymerization ; (S)-(+)-1-(2-pyrrolidinylmethyl)pyrrolidine ; optical resolution ; high performance liquid chromatography ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A novel monomer, phenyl[bis(2-pyridyl)]methyl methacrylate (PB2PyMA), was synthesized. The solvolysis rate of PB2PyMA measured in CDCl3-CD3 OD [1/1 (v/v)] by 1H-NMR spectroscopy at 35°C was much smaller than those of triphenylmethyl methacrylate (TrMA) and diphenyl-2-pyridylmethyl methacrylate (D2PyMA). PB2PyMA was anionically polymerized with the complexes of organolithiums with (-)-sparteine (Sp), (S,S)-(+)-and (R,R)-(-)-2,3-dimethoxy-1,4-bis(dimethylamino)butanes[(+)-and (-) -DDB], and (S)-(+)-1-(2-pyrrolidinylmethyl) pyrrolidine (PMP) in toluene at low temperature. The polymers obtained with Sp and DDB complexes showed low optical activity. PMP complexes, particularly that with N,N′-diphenylethylenediamine monolithium amide, were effective in synthesizing a polymer of high optical rotation ([α]25365 ∼ +1350°) which was comparable to those of poly(TrMA) and poly(D2PyMA) with one-handed helical structure. The optical rotation of poly(PB2PyMA) in a mixture of CHCl3 and 2,2,2-trifluoroethanol (9/1, v/v) slowly decreased with time. Optically active poly(PB2PyMA) coated on macroporous silica gel was able to resolve racemic compounds as a chiral stationary phase for high-performance liquid chromatography. © 1993 John Wiley & Sons, Inc.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1993.080311107
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  • 4
    Electronic Resource
    Electronic Resource
    Asymmetric polymerization of triphenylmethyl methacrylate by optically active anionic catalysts (1980)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 18 (1980), S. 3043-3051 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Triphenylmethyl methacrylate (TrMA) was polymerized with two types of asymmetric anionic catalyst, lithium (R)-N-(1-phenylethyl)anilide (LiAn) and (-)-sparteine-butyllithium complex (Sp-BuLi), at -78°C. Both catalysts yielded optically active polymers. The polymers obtained with LiAn in toluene and tetrahydrofuran (THF) showed specific rotations [α]20D of from -50° to -90° (in THF). The [α]20D of the polymer obtained with Sp-BuLi in toluene was positive and increased with polymer yield reaching above +300°s, whereas the polymer obtained in THF showed a low [α]20D (ca. +7°). Gel permeation chromatograms of both polymers obtained with LiAn and Sp-BuLi in THF exhibited rather narrow molecular weight distributions, whereas those obtained in toluene showed at least two or three components with markedly different molecular weights. The circular dichroism (CD) spectrum of the polymer obtained with Sp-BuLi showed strong positive peaks at 208 and 232 nm and a weak band at 250-280 nm; the polymer produced with LiAn showed a similar spectrum with opposite sign. The poly(methyl methacrylate)s derived from these poly(TrMA)s were highly isotactic but showed negligible rotations ([α]20D ± 2° in toluene). The polymer of high molecular weight showed clear polarization under a polarizing microscope and the low polymer obtained with LiAn appeared to show flow birefringence in chloroform at room temperature.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1980.170181013
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  • 5
    Electronic Resource
    Electronic Resource
    Reactivity of methacrylates in anionic copolymerization with methyl methacrylate by n-BuLi (1975)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 13 (1975), S. 1161-1174 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Monomer reactivity ratios, r1 and r2 were determined in the anionic copolymerizations of methyl methacrylate (MMA, M1) with ethyl (EtMA), isopropyl (i-PrMA), tert-butyl (t-BuMA), benzyl (BzMA), α-methylbenzyl (MBMA), diphenylmethyl (DPMMA), α,α-dimethylbenzyl (DMBMA), and trityl (TrMA) methacrylates (M2) by use of n-BuLi as an initiator in toluene and THF at -78°C. The order of the reactivity of the monomers towards MMA anion was DPMMA 〉 BzMA 〉 MMA 〉 EtMA 〉 MBMA 〉 i-PrMA 〉 t-BuMA 〉 TrMA 〉 DMBMA in toluene and TrMA 〉 BzMA 〉 MMA 〉 DPMMA 〉 EtMA 〉 MBMA 〉 i-PrMA 〉 DMBMA 〉 t-BuMA in THF. Except for the extremely low reactivity of TrMA and DPMMA in toluene due to steric hindrance, the order was explained in terms of the polar effect of the ester groups. A linear relationship was found between log (1/r1) and Taft's σ* values of the ester groups, where the ρ* value was 1.1. The plots of log (1/r1) vs. the 1Ha (cis to the carbonyl) and 13Cß chemical shifts of the monomers were also on straight lines. The polymer obtained in the copolymerization of MMA with TrMA in toluene by n-BuLi at -78°C was a mixture of poly-MMA and a copolymer, suggesting that there exist two kinds of growing centers.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1975.170130512
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  • 6
    Electronic Resource
    Electronic Resource
    Microstructure of the copolymers of methyl methacrylate with other methacrylates obtained by radical and anionic copolymerizations in tetrahydrofuran (1979)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 17 (1979), S. 1215-1225 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Monomer reactivity ratios r1 and r2 were determined in the copolymerizations of methyl methacrylate (MMA, M1) with 1, 1-diphenylethyl (DPEMA), α,α-dimethylbenzyl (DMBMA), tert-butyl (t-BuMA), diphenylmethyl (DPMMA), phenyl (PhMA), and 1-naphthyl (NpMA) methacrylates (M2) in tetrahydrofuran (THF) by azobisisobutyronitrile (AIBN) at 60°C and butyllithium (n-BuLi) at -78°C. The reactivities of the monomers were explained in terms of the polar effect of the ester groups in both copolymerizations. All the copolymers isolated in low yields were converted to PMMA either directly or by copoly(MMA - methacrylic acid) to determine the triad tacticities of the copolymers. Coisotactic parameters σ12 and σ21 were determined by assuming the terminal model statistics. The σ21 values always accorded to the σ21 values within experimental error, and in radical copolymerizations they were between isotactic parameters σ11 and σ22 of the homopolymerizations of MMA and M2 monomers. In anionic copolymerizations, however, the σ12 = σ21 values varied, depending on the M2 monomers. In copolymerization with DPEMA the values were less than both σ11 and σ22 with DMBMA they were between σ11 and σ22, with DPMMA, nearly equal to σ11, and with PhMA and NpMA, greater than both σ11 and σ22. The application of these parameters to copolymerizations performed at high conversion was also investigated.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1979.170170424
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  • 7
    Electronic Resource
    Electronic Resource
    Anionic polymerization of N-methacryloylaziridine (1981)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 19 (1981), S. 2647-2650 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1981.170191023
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  • 8
    Electronic Resource
    Electronic Resource
    Asymmetric selective polymerization of racemic 1,2-diphenylethyl methacrylate with the ethylmagnesium bromide-(-)-sparteine complex (1984)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1831-1837 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Asymmetric selective (or stereoelective) polymerization of racemic 1,2-diphenylethyl methacrylate (DPEMA) with ethylmagnesium bromide (EtMgBr)-(-)-sparteine catalyst was studied in toluene at -78°C. In the polymerization (S) enantiomer was consumed preferentially and the enantiomeric excess of initially polymerized (S) enantiomer was consumed preferentially and the enantiomeric excess of initially polymerized DPEMA was greater than 90%. Optically pure (R) monomer was recovered at about 70% polymer yield. Poly(DPEMA) obtained with EtMgBr-(-)-sparteine complex was highly isotactic. It was found in the polymerization of optically active DPEMA that optical rotation of poly(DPEMA) was dependent on the tacticity and that isotactic and syndiotactic poly(DPEMA)s showed opposite optical rotations. Circular dichroism spectra of the optically active polymers were measured.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1984.170220805
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  • 9
    Electronic Resource
    Electronic Resource
    Stereospecific polymerization of o-methoxystyrene by anionic initiators (1969)
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-1: Polymer Chemistry 7 (1969), S. 1933-1946 
    Details
    ISSN: 0449-296X
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: o-Methoxystyrene was polymerized with n-butyllithium (n-BuLi), Na naphthalene, and K dispersion as initiators in tetrahydrofuran (THF) and toluene. The stereoregularity of the polymer was investigated by means of the NMR spectroscopy. The methoxy resonance of the spectrum split into ten components due to the tactic pentads. It was found by x-ray examination that the polymer obtained by n-BuLi in toluene at -45°C was crystalline and highly isotactic. In THF, the stereospecificity of the polymerization was independent of the initiator, and the isotacticity of the polymer increased with increasing reaction temperature. In toluene, the stereospecificity depended on the initiator; i.e., n-BuLi gave a polymer with higher isotacticity than that given by phenylsodium. The fraction of isotactic triad of the polymer obtained by n-BuLi in toluene at -78°C was more than 90%, but 50% at 50°C. The presence of ca. 1% THF in toluene led to a steep decrease in the isotacticity even at -78°C. The tacticity of the polymer given by Na naphthalene was not affected by the existence of NaB(C6H5)4 in THF. The polymerization in THF could be explained by Bovey's “single σ” process, while a penultimate effect was observed in the polymerization by n-BuLi in toluene.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1969.150070732
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  • 10
    Electronic Resource
    Electronic Resource
    Poly(β-amino acid)s. IV. Synthesis and conformational properties of poly(α-isobutyl-L-aspartate) (1978)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 16 (1978), S. 2237-2251 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(α-isobutyl-L-aspartate) was prepared by the polycondensation reaction of p-nitrophenyl ester of α-isobutyl-L-aspartate and the conformation of the poly(β-amino acid) was investigated by X-ray diffraction, polarized infrared, circular dichroism (CD), optical rotatory dispersion (ORD), and NMR spectroscopy. α-Isobutyl β-p-nitrophenyl-L-aspartate hydrochloride and hydrobromide were used as monomers and dimethylformamide, chloroform, and chlorobenzene, as solvents. A high-molecular-weight polymer with [η] 1.0 dl/g (dichloroacetic acid, 25°C) was formed in the polymerization of the hydrochloride in chloroform at 25°C. The X-ray diagram and polarized infrared spectrum of the stretched polymer film obtained from a chloroform solution suggested a cross-β-form as the most probable structure in the solid state. The CD spectra of the polymer in a 2,2,2-trifluoroethanol (TFE) solution and its film cast from the solution showed a peak at 205 nm and a trough at 190 nm which were assigned to a β-structure. The polymer was associated in chloroform. The NMR and ORD spectra in chloroform were similar to those in TFE, which suggests that the polymer also exists in the β-structure in chloroform. The addition of small amounts of dichloroacetic acid and sulfuric acid to chloroform and TFE solutions, respectively, destroyed the β-structure. A random copolymer of α-isobutyl-L-aspartate with β-alanine was also prepared by polycondensation reaction. The copolymer apparently did not form an ordered structure in the solid state or in solution.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1978.170160913
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