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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Journal of inclusion phenomena and macrocyclic chemistry 6 (1988), S. 647-651 
    ISSN: 1573-1111
    Keywords: Cyclotriveratrylene ; halomethyloctyl ethers ; dimethoxybenzene
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Cyclotriveratrylene (CTV) can be readily synthesized by chloromethylation or bromomethylation of dimethoxybenzene with halomethyloctyl ether in the presence of SnCl4. The reaction provides the trimer exclusively and in high yield. Recrystallizations from benzene or CHCl3 yielded the solvent inclusion complexes and did not remove other inclusion impurities. Flash chromatography on silica yielded the pure CTV.13C NMR shows only five signals and no impurities.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 657-667 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Bis-(2,4-dinitrophenyl)glycols are stable in the presence of triethylamine but undergo ethanolysis in the presence of hydroxide ions. The quantitative removal of the DNP blocking group allows an integrated scheme to pure glycols from commercially available polyethylene glycol mixturesMixtures of ethylene glycol oligomers are obtained by anionic polymerization of ethylene oxide. See, for example, G. O. Curme and F. Johnston, Glycols, Reinhold, New York, 1953. They are commercially available (as PEG-200, PEG-400, etc., to indicate the average molecular weight of the major components). by bis-dinitrophenylation, chromatographic separation, and end-group removal, using high performance liquid chromatography (HPLC) of the bis-(2,4-dinitrophenyl)glycols for purity monitoring. A facile synthetic method for the production of penta-to dodecaglycols in a mixed, aqueous, dioxane solvent system, with fair yields, is also described. The bis-(2,4-dintrophenyl) protection of glycols is a reversible reaction that can be used as (1) a preparative method for pure glycols from readily available commercial polyethylene glycol mixtures; (2) a highly sensitive and accurate analytical methodA. Warshawsky, A. Tishbee, and N. Shoef, J. Liq. Chromatogr., submitted for publication. coupled with HPLC.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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