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II. On Aniline Derivatives. 

 By Edmund J. Mills., D.Sc, F.R.S* 



THE following results in connexion with aniline derivatives 

 were obtained during the course of an investigation for 

 which the substances that will be referred to were required. 



Separation. — When chloraniline, bromaniline, &c. are pre- 

 pared by acting on an anilide with chlorine &c, the function has 

 usually a double period ; so that mono-, di-, and tri- derivatives 

 are generated in presence of each other. In order to separate 

 these I proceed as follows. The mixed derivatives are immersed 

 in a very large excess of aqueous hydric chloride (1 vol. common 

 fuming chloride to 9 vols. w r ater) and heated to nearly 100°, 

 with frequent stirring, for about an hour in a loosely covered 

 vessel ; the whole is then allowed to cool down until the next 

 day. The clear liquid contains only mono- and di- derivatives, 

 the insoluble portion di- and tri- derivatives. The latter is sub- 

 mitted to repeated hydrochloric treatment as before, until the 

 supernatant clear liquid no longer gives any precipitate with 

 ammonia ; it then consists of tri- derivative only — contaminated, 

 indeed, with some black tarry products. This derivative can be 

 purified by distillation per se, or from strong aqueous hydric 

 chloride or potash-lime. The clear liquids are united and precipi- 

 tated with ammonia during twenty-four hours, a large excess of 

 ammonia being avoided. The precipitate is then w T ashed, rapidly 

 evaporated with hydric chloride to dryness on the water-bath, 

 redissolved (or at any rate well stirred) in hot water, and left to 

 cool thoroughly : the insoluble portion consists of di- derivative, 

 and must be filtered off. The filtrate is again evaporated to 

 dryness and stirred with hot water &c. Three evaporations to 

 dryness are necessary, and usually sufficient ; and the final so- 

 lution contains mono- derivative only, which yields but an inap- 

 preciably small amount of insoluble residue when so evaporated. 

 The mono- derivative can be purified by distillation from aqueous 

 soda in a current of steam ; the di- derivative by distillation per 

 se, or by successive crystallizations from naphtha and spirit. 



When aniline is intended to be converted into chlorine, bro- 

 mine, or iodine derivatives, it should be dried and purified by 

 cohobation for a few hours with about one eighth to one sixteenth 

 of its weight of mercuric chloride, bromide, or iodide respectively. 

 Subsequent fractional distillation easily furnishes a very pure 

 product. Only aniline so purified is referred to in the following 

 experiments. 



Preparation. — (a) Aniline is cohobated with glacial hydric 



* Communicated 03' the Author. 



