ISSN:
0170-2041
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Importance of Association Phenomena of Quaternary Onium Salts in the Organic Phase Responsible for the Course of Phase-Transfer-Catalysed ReactionsAs shown by vapour pressure osmometry quaternary ammonium- and phosphonium salts are associated in benzene and chloroform. [The degree of association is greater in benzene (factor 4-15) than in chloroform (factor 1.2 - 2.4).] The rate of the model reactions (1) and (2) is faster the higher the degree of association; in the two-phase system the rate is however slower due to the water content of the organic phase, which diminishes the association. Association phenomena are obviously essential for the “catalysis” in the two-phase-system.
Notes:
Quartäre Oniumsalze sind, wie dampfdruckosmometrische Messungen zeigen, in Benzol und Chloroform assoziiert [in Benzol stärker (Faktor 4-15) als in Chloroform (Faktor 1.2 - 2.4)]. Im Homogen- und Zweiphasensystem laufen die Modellreaktionen (1) und (2) mit steigendem Assoziationsgrad schneller ab - langsamer im Zweiphasensystem wegen des Wassergehaltes der organischen Phase (Verminderung des Assoziationsgrades). Assoziationsphänomene sind offensichtlich für die “Katalyse” im Zweiphasensystem wesentlich.
Additional Material:
1 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jlac.198019800603
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