48 PROCEEDINGS OP THE AMERICAN ACADEMY. 



The methyl ester of mucobromoxime is readily soluble in alcohol, 

 somewhat more sparingly soluble in ether, and very sparingly soluble 

 in chloroform or benzol. It is also very sparingly soluble in cold 

 water, but dissolves freely on heating, and, if the solution is quickly 

 cooled, it separates in finely felted needles. On continued boiling it 

 is converted into dibrommaleinimide, and the same change is also 

 effected by longer boiling with methyl alcohol. The ester melts at 

 146-147°, and at a slightly higher temperature solidifies with the 

 formation of dibrommaleinimide, which again melts at 218°. The 

 conversion of the ester into the imide may also be brought about by 

 dissolving it in sodic carbonate, and acidifying the solution with hydro- 

 chloric acid. The imide melting at 218° is thus thrown down. If 

 the alkaline hydrates are used to dissolve the ester, great care must be 

 used to avoid an excess. This same ester may also be made by the 

 action of hydroxylamine hydrochlorate upon methyl mucobromate dis- 

 solved in methyl alcohol. We found, however, that substantially no 

 reaction took place when a ten per cent solution of the ester stood at 

 ordinary temperatures for several days, either with free hydroxyl- 

 amine or with its hydrochlorate. The solutions when cooled with ice 

 and salt deposited no crystals in material amount, and on dilution 

 with water the original ester was recovered essentially unchanged. 

 With free hydroxylamine there seemed to be but slow action even on 

 boiling; but on boiling the solution containing the hydrochlorate for 

 half an hour, a copious separation of the methyl ester of the muco- 

 bromoxime melting at 146-147° was obtained on cooling. On boil- 

 ing for a longer time this ester was almost wholly converted into 

 dibrommaleinimide melting at 218°. 



Although it had been found that the methyl ester of mucobrom- 

 oxime could not be dissolved in alkalies without the formation of 

 dibrommaleinimide, it seemed to us possible that we might form a 

 silver salt. On the addition of an alcoholic solution of argentic nitrate 

 to an alcoholic solution of the ester, no salt was precipitated, and no 

 crystals separated on standing. Alcoholic ammonia was then cau- 

 tiously added, and the first drop brought do*vn a heavy yellow pul- 

 verulent precipitate, although the addition of two molecules was 

 necessary to complete the precipitation. The salt was insoluble in 

 water or alcohol, and was not affected by an excess of ammonia. On 

 aualysis it proved to be an ammonio-silver salt of dibrommaleinimide, 

 corresponding to the ammonio-silver compound of dichlormaleinimide 

 described by Ciamician and Silber.* Nitric acid decomposed it with 

 the liberation of dibrommaleinimide. 



* Benclite d. deutscli chem. Gesellsch., XVI. 2394. 



