340 ALPHATOLUIC ACID, ETC. 



b. Alphatoluic Acid (Phenylacetie Acid). 

 C 6 IF.CIF.C0.6H. 



Is produced by boiling benzyl cyanide (p. 276) with 

 alkalies ; by the action of hydriodic acid on mandelic 

 acid ; together with methyl alcohol and oxalic acid by 

 boiling vulpic acid with barium hydroxide ; by melt 

 ing atropic acid with caustic potassa ; its ethyl ether 

 by heating a mixture of monobrombenzene and ethyl 

 chloracetate with copper to 180-200. Crystallizes in 

 broad, lustrous laminae. Very similar to benzoic acid. 

 Fuses at 76.5, and boils without decomposition at 

 261-262. Oxidized with chromic acid, it is converted 

 into benzoic acid. 



When bromine and nitric acid are allowed to act 

 upon alphatoluic acid without the aid of heat, substi 

 tution-products result which consist principally of 

 members of the para-series, and by oxidation yield para- 

 brom- or paranitrobenzoic acids. Together with these, 

 in small quantities, are formed isomeric compounds, pro 

 bably belonging to the meta-series. 



When mandelic acid is heated with concentrated hy 

 drochloric acid to 140-150, and when bromine acts 

 upon heated alphatoluic acid, another class of substitu 

 tion-products is formed, in which the hydrogen of the 

 acetic acid residue is replaced (for example : phenyl- 

 chloracetic acid C 6 H 5 .CHC1.CO.OH). 



3. Adds, C 9 IP0 2 . 



1. Mesitylenic acid, CW (1:3: 5). Is 



formed by oxidizing mesitylene with dilute nitric acid. 

 The crude acid is purified like para-toluic acid. Crystal 

 lizes from water in small, colorless needles, from alco 

 hol in large, transparent, monoclinate crystals. Almost 

 insoluble in cold water, very difficultly in hot water, 

 very easily in alcohol. Fuses at 166, and sublimes with 

 out undergoing decomposition. By further oxidation, 

 it is converted into uvitic and trimesic acids. Distilled 

 with an excess of lime, it yields meta-xylene. 



