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  • 1
    Electronic Resource
    Electronic Resource
    Synthesis of poly(1-methyl-1-phenyl-1-silapentane) by chemical reduction of poly)1-methyl-1-phenyl-1-sila-cis-pent-3-ene with diimide (1991)
    Springer
    Polymer bulletin 25 (1991), S. 621-624 
    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 Poly(1-methyl-1-phenyl-1-silapentane) (I) has been prepared by the chemical reduction of the carbon-carbon double bonds of poly(1-methyl-1-phenyl-1-sila-cis-pent-3-ene (cis-II) with diimide, which was generatedin-situ by the thermal decomposition ofp-toluenesulfonhydrazide in refluxing toluene. At lower temperature (100°C),cis-II is isomerized byp-toluenesulfinic acid to lower molecular weight poly(1-methyl-1-phenyl-1-sila-cis andtrans-pent-3-ene) (cis/trans-II). Protodesilation of I with trifluoromethanesulfonic acid yields poly(1-methyl-1-trifluoromethanesulfonyl-1-silapentane) (III). The structures of I andcis/trans-II have been characterized by1H,13C and29Si NMR, GPC, TGA and elemental analysis. The structure of I has been characterized spectroscopically by1H,13C,19F and29Si NMR.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01032655
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  • 2
    Electronic Resource
    Electronic Resource
    Synthesis and microstructure of poly(1-phenyl-1-sila-cis-pent-3-ene) (1991)
    Springer
    Polymer bulletin 25 (1991), S. 63-69 
    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 poly(1-Phenyl-1-sila-cis-pent-3-ene) (I) has been prepared by the anionic ring opening polymerization of 1-phenyl-1-sila-cyclopent-3-ene (II). This reaction is co-catalyzed by n-butyl-lithium and HMPA in THF at low temperature. I has been characterized by 1H, 13C and 29Si NMR, IR, UV, GPC and TGA. The low molecular weight of l permits end group analysis. Pyrolysis of l gives significant char yields.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00338900
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  • 3
    Electronic Resource
    Electronic Resource
    Anionic ring opening polymerization of 1-phenyl-1-vinyl-1-silacyclopent-3-ene (1991)
    Springer
    Polymer bulletin 26 (1991), S. 625-628 
    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 Poly(1-phenyl-1-vinyl-1-sila-cis-pent-3-ene) (I) has been prepared by the anionic ring opening polymerization of 1-phenyl-1-vinyl-1-silacyclopent-3-ene (II) co-catalyzed by n-butyllithium and hexamethylphosphoramide (HMPA) in THF at-78°C. I has been characterized by 1H, 13C and 29Si NMR as well as by IR and UV spectroscopy. The molecular weight distribution of I has been determined by gel permeation chromatography (GPC), its thermal stability by thermogravimetric analysis (TGA) and its glass transition temperature (Tg) by differential scanning calorimetry (DSC). Thermal degradation of I in an inert atmosphere gives a twenty-seven percent char yield.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00313216
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  • 4
    Electronic Resource
    Electronic Resource
    Preparation and properties of high molecular weight poly(1-germa-) or poly(1-sila-cis-pent-3-enes) (1991)
    Springer
    Journal of inorganic and organometallic polymers and materials 1 (1991), S. 199-210 
    Details
    ISSN: 1572-8870
    Keywords: Germanium ; silicon ; high molecular weight polymers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract High molecular weight poly(1,1-dimethyl-1-germa-cis-pent-3-ene), poly(1,1-diphenyl-1-germa-cis-pent-3-ene), poly(1,1-dimethyl-1-sila-cis-pent-3-ene), and poly(1-methyl-1-phenyl-1-sila-cis-pent-3-ene) have been prepared. The thermal stability of these polymers is found to increase with their molecular weight.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00701319
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  • 5
    Electronic Resource
    Electronic Resource
    Cyclopropanation of poly[(methylphenylsilanediyl)-(Z)-butenylene]. Synthesis and characterization of poly[(methylphenylsilanediyl)methylenecyclopropylenemethylene] (1990)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 191 (1990), S. 2173-2180 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Poly[(methylphenylsilanediyl)methylenecyclopropylenemethylene] (3a) was prepared by cyclopropanation of the C—C double bonds of poly[(methylphenylsilanediyl)-(Z)-butenylene] (2a) by a Simmons-Smith reaction. Alternatively, 3a was prepared by a Birch reduction of the dichlorocarbene adduct poly[(methylphenylsilanediyl)methylene(2,2-dichloro-1,3-cyclopropanediyl)-methylene] (4a). Both 3a and 4a show the characteristic absorptions in the 1H, 13C, and 29Si NMR, IR and UV spectra. Their molecular weight distributions, determined by GPC, are rather broad and their thermal stabilities (by TG) are relatively high.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1990.021910918
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  • 6
    Electronic Resource
    Electronic Resource
    Studies on organophosphorus compounds. XXXVI.For Part XXXV, see S. S. Li, Z. Y. Chen and C. Y. Yuan Scientia Sinica (Series B) 136, (1989).. Substituent effects of alkylphosphonates and -phosphinates in alkaline hydrolysis (1990)
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 3 (1990), S. 48-54 
    Details
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Alkaline hydrolysis of diethyl alkylphosphonates and alkyl diethylphosphinates was studied in aqueous dimethyl sulphoxide. The behaviour of these acyclic phosphorus esters is very similar to that of some cyclic phosphorus esters. Rate constants were measured at three temperatures over a 30°C range, and the activation functions of the reaction were estimated. The basic hydrolytic process was proved to be a bimolecular AE reaction. Multiple regression analyses involving rate constants and substituent parameters gave, as a rule, poor results using steric constants derived from carbon compounds. However, the substituent steric effect on the rate of hydrolysis of phosphonates and phosphinates studied correlated very well with ΔΔE, representing the difference in steric energy calculated by molecular mechanics. It is attributed to the various degrees of susceptibility of carbon and phosphorus atoms to the steric hindrance of the substituents. Moreover, Newman's rule of six for the hydrolytic reaction of carboxylates was completely eliminated in phosphorus ester hydrolysis.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/poc.610030110
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  • 7
    Electronic Resource
    Electronic Resource
    Studies on organophosphorus compounds XXXII. A molecular mechanics study of the hydrolytic reaction of alkylphosphonates and alkylphosphonyl chlorides (1989)
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 2 (1989), S. 146-160 
    Details
    ISSN: 0894-3230
    Keywords: Organic Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The alkaline hydrolysis of several alkylphosphonates and alkylphosphonyl chlorides has been investigated by molecular mechanics calculations (MM2, 1985 version). The difference of the steric energies (ΔE) between tetracoordinate substrate and pentacoordinate transition state of phosphorus compounds represents the activation energy (ΔE≠) in hydrolysis. The change of ΔE for various alkyl groups relative to methyl group (ΔΔER) is suggested as a measure of the steric effect of substituents. Thus the correlation analysis involving log k and ΔΔER of the branched alkyl group gives good results and it is reasonable to anticipate that analogous treatment using ΔΔER for the straight chain alkyl group is not satisfactory owing to the minor contribution of steric effect of the latter. However, the multiple regression analysis of log k with ΔΔER and Taft's σ* provides very good results. As shown by us, for the hydrolytic reactions studied, the proposed ΔΔER is much better than Taft's Es and Charton's ν, the commonly used well-known steric parameters in the chemistry of carbon compounds.
    Additional Material: 7 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/poc.610020207
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