ISONAPIITHOL. 399 



2. Isonaphthol 



C 10 H 8 = C 10 H 7 .OH. 



Is obtained, like naphthol, from potassium /3-sulpho- 

 naphthalate. Small, colorless, rhombic plates ; fusing 

 point, 122 ; boiling point, 285-290 ; easily sublim- 

 able. Difficultly soluble in boiling water; easily in 

 alcohol and ether. 



The derivatives of isonaphthol are prepared like 

 those of naphthol. 



Isonaphthol-ethylether, C 10 H 7 .O.C 2 H 5 . Colorless, 

 crystalline mass ; fusing point, 33. 



Isonaphthol-acetate, C 10 IF.O.C 2 H 3 0. Small, color- 

 less needles; fusing point, 60. 



Dinitro-isonaphthol, C 10 H 5 (]Sr0 2 ) 2 .OH. Is obtained 

 by warming an alcoholic solution of isonaphthol with 

 dilute nitric acid. Lustrous, bright-yellow needles ; 

 fusing point, 195. 



{OTT 

 SO 2 OH 



Small, colorless laminated crystals ; fusing point, 125 ; 

 not deliquescent, but easily soluble in water and alco- 

 hol. The aqueous solution turns slightly green on the 

 addition of iron chloride, and, when heated with it, it 

 deposits brown flocks. 



Isonaphthyl sulphydrate, C 10 H 7 .SH. Small, lus- 

 trous scales ; fusing point, 136 ; not volatile with water 

 vapor ; insoluble in water ; easily soluble in ether and 

 alcohol. 



3. Dioxynaphthalene. 

 C 10 H 8 2 = C'H 6 (OH) 2 . 



Is obtained by melting potassium disulphonaphtha- 

 late with potassium hydroxide. Colorless needles, 

 which become violet in the air; difficultly soluble in 

 water, easily in alcohol and ether ; s.ublimable ; in an 

 alkaline solution it absorbs oxygen rapidly from the 

 air, and turns black. 



