SynopsisThe chromatographic analysis of resol solutions in tetrahydrofuran solvent, by means of a set of columns packed with crosslinked polystyrene gels, has been carried out with adequate resolving power for a clear-cut qualitative or semiquantitative difierentiation between various types of resols to be practicable. The resulting chromatograms, which show the distribution of different constituents by molecular size, could be interpreted by the use of reference substance and by calibrating the system with a number of compounds of known structures. The method has been used to investigate the way in which various reaction parameters (nature of catalysts, proportion of starting material, treatments undergone by the resols) affect the composition of resols. Different commercial products have been thus characterized. It has also afforded an insight into the progress of the polycondensation reaction as a function of time and helped to state the reactivity of different groups and unblocked ring positions. Thus, an hydroxymethyl group appears to be more reactive in the para than in the ortho position. Otherwise the reactivity of unblocked ring positions would be enhanced by an hydroxymethyl group in the ortho rather than para position.
Aus dem chemischen Laboratorium des Hofrates Prof. Ad. Lieben an der k. k. UniversitS~t in Wien. (Vorgelegt in der Sitzung am 13. Oktober 1904.) In zahlreichen F~llen fand man, daf5 durch die Einwirkung verdi.'mnter Schwefels~iure auf Pinakone unterYVasserabspaltung und einer eigenttimlichen Umlagerung KSrper von Ketoncharakter, sogenannte Pinakoiine, entstehen. Bei dieser Reaktion ist das Pinakolin das einzige Produkt der Einwirkung, wie Fittig in seinem Berichte tiber die Darstellung des erste~ Pinakolins ausdKicklich hervorhebt.1 Im vorigen Jahre wurde auf Anregung Prof. Lieben's von K. Zumpfe die Einwirkung verdtinnter Schwefels~iure auf Butyronpinakon untersucht und da ergab sich, daft kein Pinakolin entstanden war, sondern zwei Produkte in nahezu gleicher Menge: ein unges~ttigter Kohtenwasserstoff und ein Oxyd. Auf Veranlassung des Herrn Hoffates Prof. Dr. Ad. Lieben unternahm ich es nun, die Einwirkung verdtinnter Schwefels~iure auf Propionpinakon zu untersuchen. Das Propionpinakon. Dieses Pinakon wurde zum ersten Mal yon Schramm dargestellt. ~ Ich unterschichtete das zu reduzierende Ditithylketon mit einer 20prozentigen Pottaschel6sung und liefi 1 Annalen, 11d, 56. 2 Berichte der Doutschen chem. Ges., 15, 1584.
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