102 Journal of the Mitchell Society [April 



dilute hydrocliloric acid and filter. After many experiments 

 we proceeeded as follows. The alcoholic solution is poured 

 into 5000 cc. 12 per cent, hydrochloric acid and heated to 

 boiling till practically all of the precipitated product has redis- 

 solved. Small insoluble impurities were filtered off on a Buch- 

 ner funnel with suction while the solution was hot. On allow- 

 ing the filtrate to stand over night, a mass of yellow needles had 

 separated. These were filtered off, washed with water and 

 dried. The yield was 9 grams. The product melted at 153°. 

 The crystals are a dull yellow but powder to a bright yellow 

 mass. The compound is easily soluble in alcohol and chloro- 

 form, fairly soluble in. carbon tetrachloride and only slightly 

 soluble in gasolene. The solutions turn red on standing even 

 when air is displaced by nitrogen. 'Solutions in alkalies are blue 

 with a brilliant fluorescence. The sodium or potassium salt 

 which separates out however is that of naphtazarine. This 

 oxidation we found will take place even at 0° and in an at- 

 mosphere of carbon dioxide. The tetrahydroxynaphthalene is 

 therefore very sensitive to alkalies. 



Preparation of Phenylsemicarhazine 

 Phenylsemicarbazine was prepared by first making pheny- 

 lurea from aniline by the action of potassium cyanate and then 

 treating this with hydrazine hydrate. In order to make the 

 phenylurea the method of W. Weith (Ber., 9,820) was fol- 

 lowed. One molecule (25g) aniline was mixed slowly with one 

 molecule (25cc. sp. gr. 1.17) hydrochloric acid. The mass was 

 cooled and one molecule (21. 8g) of potassium cyanate was 

 added slowly. The nearly solid mass was filtered, washed and 

 dried on a porous plate. Yield, 26g. The melting point was 

 147°. The formula of phenylurea is NHo.CO.NHCgHs. To 

 convert the phenylurea into phenylsemicarbazine the method of 

 Curtius and Burkhardt (Journ. f. prakt. Chem., (2) 58,220) 

 was followed. Ten grams of phenylurea were placed in a small 

 round bottom flask with 5g absolute alcohol and 8g hydrazine 

 hydrate. The flask was attached to a reflux condenser with a 

 ground glass joint and the mixture was boiled fifteen hours. On 

 cooling the mass solidified. This was rinsed out into a porcelain 



