American Chemical Journal, Vol. 38

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Excerpt from American Chemical Journal, Vol. 38: July December, 1907 In order to study the equilibrium phenomena of the tautomeric amide groups of phenylurazole and the other urazoles, the study of the action of diazomethane on these compounds was undertaken. In phenylurazole is the 2, 3 amide group a ketone, - NHCO -, or an enol, -N: C(OH) -, or a mixture of the two in equilibrium? Is the 4, 5-amide group present only in 1 form or in 2 forms in equilibrium? Obviously, to secure light on this question it would be necessary to bring phenylurazole and other urazoles into reaction with some reagent that would act readily with both keto and enol forms under conditions which would, as far as possible, exclude the possibility of changing the ratio of the amounts of the 2 tautomeric forms or causing the rearrangement of either one of the derivatives into another. Diazomethane seems to be a reagent admirably suited to this purpose. It has been proved that diazomethane reacts very readily with substances known to have the keto and enol structure, and it has further been shown that the methyl derivatives of phenylurazole do not rearrange into each other under the conditions of the experiments. When phenylurazole is treated, in ether, with an excess of diazomethane nearly pure 1-phenyl-3-methoxy-4-methylurazole is formed. There are present, however, traces of other dimethyl derivatives not yet identified. When phenylurazole is treated with only 1 molecule of diazomethane, about 95 per cent of 1-phenyl-3-methoxyurazole and 5 per cent of 1-phenyl-2-methylurazole are formed. 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.