THE REACTION OF CYANOGEN WITH ORGANIC COMPOUNDS. I. SECONDARY ALIPHATIC AMINES^{1, 2, 3}

Abstract

This paper is the first of a series in which will be reported the results of an extensive study of the reactions of cyanogen with organic compounds. On the basis of its inorganic reactions cyanogen has repeatedly been compared to the halogens (1,2). Some early work even indicated that a similar comparison could be made in the field of organic chemistry. Merz (3), for example, reported that a mixture of benzene vapor and cyanogen passed through a red hot tube gave benzonitrile, terephthalic acid nitrile, and hydrogen cyanide. Desgrez (4) studied the effect of aluminum chloride and cyanogen on boiling benzene. Decomposition of the reaction products with concentrated hydrochloric acid yielded benzonitrile, benzoyl cyanide, benzil, and unidentified compounds. Vorlander (5) claimed that toluene, diphenyl, ethylbenzene, and phenetole behaved in a similar manner.However, Machek's report (6) that catechol in aqueous solution reacted with cyanogen to give a 52% yield of 2,3-dihydroxybenzonitrile did not stand up on reexamination, and Hahn and Leopold (7) concluded later that the reaction consisted of condensation between the phenolic and cyano groups and that no nuclear substitution had taken place. Even aniline, which brominates with such extreme ease, produced symmetrical N , N-diphenyloxamidine (8) instead of aminocyanobenzene.Brief investigation of alcohols, aldehydes, phenylhydrazine, semicarbazide, diphenylguanidine, and benzylamine (9) also showed that comparison with halogens was a poor premise on which to base predictions regarding cyanogen chemistry.The behavior of each of the amino compounds above could be described as an aminolysis of cyanogen. Under such circumstances the absence from the literature of reactions between cyanogen and aliphatic amines was particularly intriguing. A series of preliminary experiments, consisting in the saturation of a large number of organic liquids and solutions, was, therefore, undertaken and it was quickly indicated that reactions with primary aliphatic amines, secondary aliphatic amines, aliphatic diamines, and mercaptans could be expected once the proper conditions were discovered. The investigation of these reactions has since been actively pursued and the results of one such study are reported in this paper.

The Synthesis And Chemistry Of Cyanogen

“…Aromatic amines and ammonia were found by earlier workers to react readily with cyanogen to give oxamidines and numerous unidentified by-products, the identities of which have still not been determined. The reactions of aliphatic and heterocyclic amines with cyanogen, which had not been reported prior to 1950, have recently been studied in a comprehensive manner by Woodburn and associates (215,216,218,219,221,222).…”

THE REACTION OF CYANOGEN WITH ORGANIC COMPOUNDS. II. PRIMARY ALIPHATIC AMINES1, 2

“…The isolation of cyanoformamidines as the reaction product of secondary amines (1), while oxamidines resulted from primary amines suggested that the course of the cyanogen-amine reaction might be through initial formation of cyanoformamidine with further addition sterically hindered in the secondary amines. Experiments were, therefore, run with secondary amines which involved changes in the original procedures (1) as to solvent, cyanogen-amine ratio, and mode of recovery, with the result that a di-addition compound of cyanogen and NHNH dimethylamine, (CH3)2NC-CN(CH3)2, was finally isolated in the form of its hydrochloride, together with the expected cyanoformamidine. No other secondary amine has as yet yielded such a product.…”

THE REACTION OF CYANOGEN WITH ORGANIC COMPOUNDS VIII. 2-MERCAPTOETHYLAMINE AND ITS ALKYL DERIVATIVES1

“…Previous papers in this series (1) have shown that the reactions of cyanogen with unifunctional primary amines, secondary amines, and mercaptans are quite straightforward, but that with ethylenediamines the vicinal amino groups have a mutual effect which makes the course of the reaction difficult to predict (2). This paper reports a continuation of the study of bifunctional compounds, in particular those containing both amino and mercapto groups.…”