SALICYLIC ACID. 345 



droxide (dissolved in alcohol), and 3-4 parts of methyl 

 iodide at 100-120, there is produced the liquid (boil- 

 ing point, 248) methyl ether of methylsalicylic acid, 



r n PTT 3 

 C 6 H 4 ] QOOCH 3 which when boiled with soda-ley 



yields sodium methylsalicylate ; from the solution of 

 this salt hydrochloric acid precipitates the free acid. 

 Large, colorless plates, difficultly soluble in cold water, 

 easily soluble in hot water and in alcohol ; fuses at 

 98.5, and above 200 is resolved into anisol (p. 291) 

 and carbonic anhydride. Strong monobasic acid. Its 

 salts are just as instable as the salicylates. 



Ethylsalicylic acid, C 6 H 4 i Is obtained 



in the same way as methylsalicylic acid. Crystalline 

 mass ; fusing point, 19.5 ; is resolved into carbonic 

 anhydride and phenol-ethylether at 300. 



Acetylsalicylic acid, C 6 H 4 1 C Q Q H is produced 



by the action of acetyl chloride on salicylic acid or 

 salicylates. Colorless, fine prisms. 



Salicylamide (Salicylamic acid), C 7 H 7 T0 2 = 



(isomeric with the amidobenzoic acids) 



C 6 H 4 < 



is produced by continued action of ammonia on gaul- 

 theria oil, and by heating ammonium salicylate. -Pale 

 yellow, crystalline laminae, difficultly soluble in water ; 

 fusing point, 142 ; sublimable. 



When salicylic acid is distilled with phosphorus 

 chloride, orthochlorbenzoyl chloride (p. 328) is pro- 

 duced. Dry chlorine tranforms it, according as sali- 

 cylic acid or chlorine is in excess, into chlorsalicylic acid, 

 C 7 H 5 C10 3 , or dichlorsalicylic acid, C 7 H 4 CP0 3 ; bromine 

 also forms brom- or dibromsalicylic acid ; iodine in alka- 

 line solution or in aqueous solution in the presence of 

 iodic acid converts it into a mixture of iodo-, diiodo- 

 and triiodosalicylic acids, which are difficult of separa- 

 tion. All these acids crystallize well, and are but 



