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LXIII. On the Benzole Series. — Part II. Note on some Deriva- 

 tives of Xylole. By Arthur H. Church, Esq.* 



WITH xylole, the third member of the benzole series, we 

 have at present but slight acquaintance. Cahours, to 

 whom we owe the discovery of this hydrocarbon, has, I believe, 

 not yet published the details of his investigation. Having had 

 occasion to prepare pure xylole in order to make a determination 

 of its boiling-point -)-, I imagined that a study of some of its 

 derivatives might prove of interest. The small quantity of pure 

 xylole having a constant boiling-point of 126 0- 2 at my disposal, 

 induced me to employ for those experiments, an account of which 

 I propose to give in the commencement of the present paper, 

 the whole of the crude xylole boiling between 124° and 130° 

 obtained from two gallons of light coal-naphtha. In following 

 the directions of Cahours for the preparation of this hydrocarbon, 

 I did not obtain from 16 oz. of the oil from wood naphtha more 

 than 1 oz., boiling at from 126° to 128°. 



1 . Preparation of Nitroxylole and Xylidine. 



Crude xylole was dissolved in nitric acid of spec. grav. 1*5, 

 the acid being kept cool ; the nitro-compound formed was then 

 separated by the addition of water, and washed until free from 

 nitric acid. Nitroxylole thus obtained is a yellow oily liquid, 

 heavier than water ; its odour is less pleasant than that of nitro- 

 benzole ; only when impure does it decompose on keeping. By 

 the well-known process of reduction the nitroxylole was con- 

 verted into xylidine ; this base was then purified by l'epcated 

 crystallization of its combination with oxalic acid ; afterwards 

 the xylidine was separated from this salt by distilling it with 

 lime. The xylidine was dissolved in hydrochloric acid, and a 

 considerable quantity of bichloride of platinum solution added. 

 At first a slight precipitate took place; this was redissolved by 

 the addition of a small quantity of water ; the whole, was then 

 set aside under a bell-jar with oil of vitriol. By fractional cry- 

 stallizations of the platinum salt I hoped to obtain a xylidine 

 compound, from which, by distillation with caustic soda or 

 potassa, pure xylidine might be procured ; for we know in many 

 cases how excellent a method of separation that of fractional 

 crystallization is, and special inquiries by Anderson, C. G. Wil- 

 liams, and others have proved the advantage of this method for 

 the purification of the platinum salts of a series of bases isomeric 

 with that to which xylidine belongs. After twelve hours, the 



* Communicated by the Author. 



t Philosophical Magazine, April lH. r >f>. 



