1870.] 



the History of Thiobenz amide. 



501 



solved in the ordinary manner by the alkali ; the benzonitrile set free at 

 the same time yields ammonia and benzoic acid. The separated acid, 

 which was recognized as benzoic acid by the sparing solubility of its sodium 

 salt, was further identified by a determination of its melting-point and an 

 analysis of the silver salt. The sulphur-compound suffers a very interest- 

 ing change by the action of nascent hydrogen. I have already* called 

 attention to the fact how much more readily the thioamides are converted 

 into the corresponding amine bases than the nitriles. This experience 

 has again been verified in the new body. "When its alcoholic solution is 

 decomposed by zinc and hydrochloric acid, sulphuretted hydrogen is 

 evolved in abundance. After ten or twelve hours the total decomposition 

 of the sulphur-compound is recognized by the addition of water no longer 

 producing any precipitate in the alcoholic solution. The new product is 

 collected and purified by a process repeatedly proved to be successful ; the 

 addition of an excess of alkali until the zinc hydrate at first thrown down 

 is redissolved leaves the base in the supernatant alcoholic layer. After 

 evaporation of the alcohol, the base still containing fixed alkali is dis- 

 solved in ether, and withdrawn from this by hydrochloric acid, whereby a 

 small quantity of brown resin is separated and remains dissolved in the 

 ether. On evaporating the hydrochloric solution on the water-bath, the 

 hydrochlorate of the base is left behind as an oil, which in a short time 

 solidifies to a mass of indistinct crystals. When the aqueous solution of 

 this salt is decomposed by ammonia, oily drops immediately separate and 

 sink to the bottom ; in the course of a day these solidify to a crystalline 

 mass, the supernatant fluid being filled with iridescent plates. 



The analysis of the hydrochlorate, purified by recrystallization from 

 water, and dried at 100°, which it can be without change, leads to the 

 formula 



C U H 15 N 2 C1 = C U H 14 N 2) HC1, 

 which was satisfactorily confirmed by a determination of the crystalline 

 platinum salt dried at 100°, containing 



C 2S H 30 N 4 PtCl 6 = 2(C U H u N 2 , HC1), PtCl 4 . 

 In the formation of the above-mentioned base 4 at. hydrogen have taken 

 the place of 1 at. of sulphur, 



C U H 10 N 2 S + 3HH = H 2 S + C U H I4 N 2 . 

 If the molecular arrangement of the sulphur body formerly indicated be cor- 

 rect, the action of the hydrogen would remove the sulphur bond from be- 

 tween the carbon atoms, and by simultaneously loosening the attraction 

 between these carbon atoms and the nitrogen atoms, the union of two 

 hydrogen atoms to each carbon atom would be rendered possible ; both 

 nitrogen atoms would then be doubly linked together. That these are, in 

 fact, very strongly united is shown by the circumstance that the new base 

 undergoes no further change under the influence of hydrogen. I had 



* Hoimann, Proc. Roy. Soc. vol. xvi. p. 445. 



