OF ARTS AND SCIENCES. 187 



each other, found the same methylfurfurol among the products 

 formed by the distillation of several species of seaweed with dilute 

 sulphuric acid, and showed that the fucusol of Stenhouse * was a 

 mixture of furfurol with this methylfurfurol. Shortly afterward 

 the same body was obtained by the action of dilute sulphuric acid 

 upon isodulcite by Maquenne,f who pointed out that this mode of 

 formation, taking into consideration the constitution of isodulcite 

 as established by Fischer and Tafel, t proved the methyl group to 

 be in the 8 position. This conclusion of Maquenne concerning the 

 structure of methylfurfurol was afterward confirmed in this Labo- 

 ratory by a study of the product formed by the action of aqueous 

 bromine upon methylpyromucic acid, and a brief description of 

 this reaction was published at the time.§ Instead of the half- 

 aldehyde of fumaric acid 



/COOH 

 C 2 H<> 



" x COH 



which is formed under like conditions from pyromucic acid, methyl- 

 pyromucic acid yields the acetacrjdic acid of Wolff, || 



GOOH 



C 2 H 2 



x COCH 3 



and the formation of this ketone acid proves that the methyl group 

 is attached to the 8 carbon atom of the furfuran ring. We have 

 also studied the action of dry bromine upon methylpyromucic acid, 

 and have found that a somewhat unstable tetrabromide may be 

 prepared, although the substitution products are more readily ob- 

 tainable. For the preparation of the tetrabromide the temperature 

 must be kept below 0°; if the bromine be allowed to act at ordi- 

 nary temperatures a brommethylpyromucic acid is formed which 

 melts at 150-151°, and contains the bromine in the furfuran ring, 

 while at higher temperatures (50-60°) the bromine enters chiefly 

 the side chain and forms w-brommethylpyromucic acid melting at 

 117-148°. The formation of these two isomeric products at dif- 

 ferent temperatures recalls the analogous reactions in the aromatic 

 series, and the analogy is completely borne out by the behavior 



* Ann. Chem. u. Pharm., LXXIV. 278. t Comptes Rendus, CIX. 603. 



J Berichte der deutsch. chem. Gesellsch., XX. 1092 ; XXI. 2173. 



§ Ibid., XXIII. 452. 



|| Ibid., XX. 426; Ann. Chem. u. Pharm., CCLIV. 245. 



