Proton magnetic resonance spectra VOLUME

The submitters purchased glacial acetic acid from Showa Denko K. K., Tokyo, Japan, and acetic anhydride from Riedel de Haen AG, Seelze-Hannover, Germany. A solution prepared from 4 volumes of glacial acetic acid, 1 volume of acetic anhydride, and a catalytic amount of p-toluenesulfonic acid was heated under reflux for 24 hours and distilled. The distillate, which contained 5% water and 4% acetic anhydride according to analysis of the proton magnetic resonance spectrum, was then used by the submitters. The water content was determined from the chemical shift of the hydroxyl proton. ... 

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