BENZENE DERIVATIVES CONTAINING NITROGEN. 385 



r<TT 3 /n TT \r\ /O> a substance is formed known as phenyl-methyl- 



^2 1 2 W^ftA^-^ 



pyrazolon, C 10 H 10 N 2 O. 



In this compound a second hydrogen atom may be replaced by 

 methyl, when phenyl-dimethyl-pyrazolon is formed, which is the 

 substance to which the name antipyrine has been given. 



Antipyrine is a white, crystalline, odorless powder, having a slightly 

 bitter taste; it fuses at 113 C. (235 F.), is soluble in less than its 

 own weight of water, in one part of alcohol, in one part of chloro- 

 form, but only in 50 parts of ether. 



Analytical reactions : 



1. 0.2 gramme of antipyrine dissolve in 2 c.c. of nitric acid with- 

 out change of color. On heating slightly the liquid assumes a yellow, 

 then an intense red color. (Plate VI., 7.) 



2. 2 c.c. of a 5 per cent, solution of antipyrine treated with a few 

 drops of potassium nitrite solution yield an intense green color on 

 the addition often drops of acetic acid. (Plate VI., 8.) In a more 

 concentrated solution green crystals of nitroso-antipyrine form on 

 standing. 



3. The addition of ferric chloride to solution of antipyrine causes 

 a deep red color. 



4. Mercuric chloride, as well as tannic acid, produces a white 

 precipitate. 



Saccharine, C 7 H 5 SO 3 N or C 6 H 4 .CO.SO 2 NH (Benzole sulphinide, 

 Anhydro ortho-sulphamine-benzoic acid). This substance is a deriva- 

 tive of benzoic acid, C 6 H 5 .CO 2 H, obtained from it by introdu- 

 cing the two bivalent radicals SO 2 and NH with elimination of 

 water. The constitution is, therefore, represented by the formula 



Practically, saccharine is not made from benzoic acid, but from 

 toluol, C 6 H 5 .CH 3 , by a series of rather complicated synthetical pro- 



cesses. 



Saccharine is a white, amorphous or somewhat crystalline powder, having a 

 very slight odor of oil of bitter almond, which becomes more perceptible on 

 heating the substance. It is but sparingly soluble in water, requiring about 400 

 parts for solution ; this solution is slightly acid and has an extremely sweet 

 taste, which is yet perceptible when saccharine "is dissolved in 70,000 parts of 

 water, which shows tjiat it is about 280 times sweeter than cane-sugar, a solution 

 of which in 250 parts of water is yet perceptibly sweet. Saccharine is soluble 



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