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  • 1
    Electronic Resource
    Electronic Resource
    Asymmetric polymerization of N-triphenylmethylmaleimide with chiral anionic initiators (1997)
    Springer
    Polymer bulletin 38 (1997), S. 509-514 
    Details
    ISSN: 1436-2449
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract. Asymmetric polymerization of N-triphenylmethylmaleimide (TrMI) is performed with chiral anionic initiators in tetrahydrofuran and toluene at − 78 and 0 °C to obtain optically active polymer. It is found that the (S)-(+)-1-(2-pyrrolidinylmethyl) pyrrolidinelithium [Li-(+)-PMP] and lithium (−)-menthoxide are effective for the asymmetric polymerization of N-triphenylmethylmaleimide in THF. The polymers obtained are characterized by circular dichroism (CD). It is inferred that the propagation reaction of polymerization of TrMI with Li-(+)-PMP is dominated by ion pair mechanism and meanwhile free ion mechanism cannot be ignored based on GPC analysis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002890050080
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  • 2
    Electronic Resource
    Electronic Resource
    Self-condensing vinyl polymerization of acrylamide (1999)
    Springer
    Polymer bulletin 43 (1999), S. 29-34 
    Details
    ISSN: 1436-2449
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary A novel approach to branched polyacrylamide was described. The branched structure resulted from the amidyl radicals which were formed by the reaction of amide groups with Cu(III) of potassium diperiodatocuprate, K5[Cu(HIO6)2], in alkaline medium and capable of initiating the vinyl polymerization of acrylamide monomer. The obtained polymer was characterized by 1H NMR, FT-IR and intrinsic viscosity measurements.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002890050529
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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
    Helix-sense-selective copolymerization of phenyl[bis(2-pyridyl)]methyl methacrylate, diphenyl(2-pyridyl)methyl methacrylate and triphenylmethyl methacrylate with chiral anionic initiators (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2127-2133 
    Details
    ISSN: 0887-624X
    Keywords: phenyl[bis(2-pyridyl)]methyl methacrylate ; (S)-(+)-1-(2-pyrrolidinylmethyl)pyridine ; anionic asymmetric copolymerization ; optically active copolymer ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Optically active poly[triphenylmethyl methacrylate-co-phenyl[bis(2-pyridyl)]methyl methacrylate] (poly[TrMA-co-PB2PyMA], poly[diphenyl(2-pyridyl)methyl methacrylate-co-phenyl[bis(2-pyridyl)]methyl methacrylate] (poly[D2PyMA-co-PB2PyMA]), and poly[triphenylmethyl methacrylate-co-diphenyl(2-pyridyl)-methyl methacrylate] (poly[TrMA-co-D2PyMA]) were prepared by helix-sense-selective copolymerization with complexes of organolithium with (-)-sparteine [(-)Sp],(S, S)-(+)- and (R, R)-(-)-2,3-dimethoxy-1,4-bis(dimethylamino)butane [(+)- and (-)DDB], and (S)-(+)-2-(1-pyrrolidinylmethyl)pyridine [(+)PMP] as anionic initiators in toluene at low temperature. The copolymers obtained with (-)Sp and (+)DDB or (-)DDB complexes of organolithium showed low optical activity, but to [(+)PMP] complex with N,N′-diphenyleneamine monolithium amide [(+)PMP-DPEDA-Li)] was effective in synthesizing copolymers of high optical rotation ([α]25D about +320 to + 370°) which were comparable to those of corresponding homopolymers with one-handed helical structure. The optical rotations of poly[TrMA-co-PB2PyMA] and poly[TrMA-co-D2PyMA] were much more stable than that of poly(D2PyMA) or poly(PB2PyMA) in a solution of CHCl3-2,2,2-trifluoroethanol (10 : 1, v/v) at 25°C, but optical rotation of poly[D2PyMA-co-PB2PyMA] slowly decreased with time in the same conditions. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2127-2133, 1998
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Block copolymerization of triphenylmethyl methacrylate with other methacrylates using (-)-sparteine/9-fluorenyllithium as an initiator (1997)
    Weinheim : Wiley-Blackwell
    Macromolecular Chemistry and Physics 198 (1997), S. 279-290 
    Details
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Diblock and triblock copolymerization of triphenylmethyl methacrylate (TrMA) with methyl methacrylate (MMA), butyl methacrylate (BuMA), benzyl methacrylate (BzMA) or diphenylmethyl methacrylate (DPMMA) in the presence of the chiral anionic complex initiator, (-)-sparteine/9-fluorenyllithium, were investigated. The resulting block copolymers show high specific rotation and were characterized by means of gel-permeation chromatography, scanning electron microscopy, nuclear magnetic resonance, circular dichroism spectra and thermal analysis.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1997.021980205
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  • 6
    Electronic Resource
    Electronic Resource
    Studies on helix-sense-selective copolymerization based on triphenylmethyl methacrylate (1994)
    Weinheim : Wiley-Blackwell
    Macromolecular Chemistry and Physics 195 (1994), S. 1177-1187 
    Details
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Helix-sense-selective copolymerizations based on triphenylmethyl methacrylate (TrMA) with methyl methacrylate (MMA), benzyl methacrylate (BzMA) and diphenylmethyl methacrylate (DPMMA) in the presence of the chiral anionic complex initiator (-)-sparteine/9-fluorenyl-lithium (1) were investigated. The studies concentrated on the stereoregularity of the copolymers, the relative reactivity of the monomers, the specific rotation of the copolymers and the influence of the solvent on the copolymerization. The results show that the match of TrMA with MMA of smaller size would favour the form of the copolymer with isotactic one-handed helix having higher specific rotation as compared with BzMA ad DPMMA in toluene, but the TrMA/MMA copolymer obtained in tetrahydrofuran possessed a very low specific rotation because of the action of the polar tetrahydrofuran on the anion complex.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1994.021950406
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