HILL AND CORNELISON. — CROTONOLACTOXES. 21 



zation from this solvent. The percentage of bromine which the sub- 

 stance contained corresponded to the formula C 4 Br 4 2 . 



I. 0.1 G85 grm. substance gave 0.3177 grm. AgBr. 

 II. 0.1884 grm. substance gave 0.3552 grm. AgBr. 



Br 



This substance crystallizes from ligroin in clustered leaflets which 

 melt at 58-59°. It has a strong suffocating odor like that of the acid 

 bromauhydrides. When heated with water it is slowly dissolved and 

 the solution then contains dibrommaleic acid. The acid was as usual 

 identified by the crystalline form of the barium salt, and by the melt- 

 ing point (114-115°) of its anhydride. On treating the body with 

 stannous chloride and hydrochloric acid the dibromcrotonolactone is 

 again formed by reduction. The mode of formation, the composition, 

 and the behavior of this body justify the conclusion that it is the un- 

 symmetrical form of dibrommaleylbromide. Its behavior will be fur- 

 ther studied in this Laboratory. We have made many unsuccessful 

 attempts to prepare an identical or an isomeric body directly from 

 dibrommaleic acid. We have tried the action of phosphoric penta- 

 bromide upon dibrommaleic anhydride at temperatures which varied 

 from 100° to 225°, and either obtained the unaltered anhydride, or else 

 carbonization ensued. We were equally unsuccessful in our attempts 

 to prepare such a product through the salts of the acid. 



Action of Aniline. 



Aniline reacts upon the a/3-dibromcrotonolactone at ordinary tem- 

 peratures and forms a-phenylamido-/3-bromcrotonolactone. This sub- 

 stance is most readily prepared by dissolving the lactone in twenty 

 parts of alcohol, diluting this solution with an equal weight of water 

 and then adding somewhat more than two molecules of aniline. On 

 standing long needles of the aniline derivative separate in abundance, 

 which may be purified by recrystallization from sixty per cent acetic 

 acid, and afterward from alcohol. 



I. 0.2570 grm. substance gave 0.4426grm. C0 2 and 0.0763 grm. H 2 0. 

 II. 0.2393 grm. substance gave 0.1775 grm. AgBr. 

 III. 0.2727 grm. substance gave 13.4 c.c. of moist nitrogen at 21° and 

 under a pressure of 763 mm. 



