The Identification of Acids, Para Halogen Phenacyl Esters: Dissertation (Classic Reprint)

Excerpt from The Identification of Acids, Para Halogen Phenacyl Esters: Dissertation The method of preparation of the esters was similar to that used in previous work1 on the identification of acids. In the case of the p-chloro phenacyl esters g. Of reagent was used, of the p-bromo esters one g and of the p-iodo esters g., equivalent to g. Of the p-bromo, the smaller quantity being used on account of lower solubility. In a few cases where the degree of solubility of the esters could be predicted, i. E., extremely soluble or diflicultly soluble, more or less of the reagent was used as desired. For the addition of solvent, the calculation of the per centage composition of solvent and the filtration and washing of pre cipitates, the method of procedure adopted by Rather and Reid (q. A), was followed. Monobasic acids were heated on the water bath for one hour, except acetic, propionic, glycolic and lactic which were heated only from '/g to hour, dibasic acids were heated 2 hours and tribasic 3 hours. The precipitation of the esters was brought about by immersion of the flask in tap-water, except in a few cases where it was necessary to cool to 0° in order to start crystallization. The reagents and acids were weighed to g. And the alcohol and water measured from pipets. Where it was possible to obtain them the alkali salts of the acids were used, otherwise the free acid was not quite neutralized with sodium car bonate in the reaction flask just before the reagent and alcohol were added. In the case of stearic, palmitic and margaric acids a solution of sodium alcoholate, containing the required amount of base, was added to the acid and warmed until the sodium salt of the acid precipitated on cooling. The reagent and solvent were then added and the ordinary procedure followed. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.