262 PROCEEDINGS OF THE AMERICAN ACADEMY 



IX. 



CONTRIBUTIONS FROM THE CHEMICAL LABORATORY OF 



HARVARD COLLEGE. 



ON MUCOPIIENOXYBROMIC ACID. 



By Henky B. Hill and Edward K. Stevens. 



Presented May 29, 1883. 



The products which are formed when mucobromic acid is treated 

 with a large excess of baric hydrate, liave already been described by 

 O. R. Jackson and one of us.* Formic and dibromacrylic acids were 

 found to be the first products of this reaction, although even in the 

 cold a part of the dibromacrylic acid was further converted into brom- 

 propiolic acid. Later experiments undertaken with the view of avoid- 

 ing this secondary decomposition, showed that an entirely different 

 reaction ensued when the conditions were so modified that the solution 

 was at no time strongly alkaline. f The chief product formed in this 

 case was easily found to be an acid containing four atoms of carbon 

 aud one of bromine; but the determination of its constitution proved 

 to be a matter of more difficulty, and a description of it must therefore 

 be postponed until it can be further studied. Since it seemed possible 

 that sodic cthylate or potassic phenylate might react upon mucobromic 

 acid and yield similar products, whose constitution could more easily 

 be determined, we turned our attention in this direction. Although 

 we have been unable to obtain any such products by the action of 

 sodic cthylate, potassic phenylate has given us well-defined products 

 containing the phenoxyl group. 



ALicophenoxyhromic Acid. 



Potassic phenylate acts upon potassic mucobromate in aqueous 

 solution at ordinary temperatures; but the isolation of the potassic 

 mucophenoxybromate thus formed is somewhat difficult, and we have 



• These Proceedings, Vol. XVL (n. s VIII.) p. 188. 

 \ Loc. C.U., p. 204. 



