304 



PROCEEDINGS OP THE AMERICAN ACADEMY 



at 216°, The analysis of the product, made at different times and 

 washed with chloroform, gave no constant figures. The halogen de- 

 terminations gave results varying from 1% to 5% too high for that 

 calculated for a dibroinide, CigHisCLOs, Br^, and this points to the 

 presence of some tetrabromide. That the bromine has been added to 

 the double bonds present in the quinone group and not to the aceto- 

 acetic ether residues follows: 1st, because the substance sublimes 

 without decomposition ; 2d, the corresponding dichlorhydroquinone- 

 diacetoacetic ether is acted upon only very slowly by bromine, and 

 then with evolution of hydrobromic acid and formation of pungent 

 derivatives affecting the eyes ; 3d, the above addition product treated 

 with zinc dust and acetic acid, or in alcoholic solution with zinc dust 

 and dilute sulphuric acid, is converted chiefly into jo-dichlorbenzo-/)-di- 

 furfuran a-dimethyl ^-dicarboxylic ether. 



The study of the product formed with bromine, though incomplete, 

 is thus sufficient to show that it is an addition product, and its study, 

 as well as that of other addition products, will be continued. 



Noteworthy is the ease with which ^-dichlorquinonediacetoacetic 

 ether adds water, and is then converted into a new quinonefurfuran 

 derivative. 



Quinone p-d/furfuran a-dimethyl ^-dicarhoxylic Ether Dihydrochloride, 



CO,C,H, 



CO.C.Hg. 



;)-Dichlorquinonediacetoacetic ether is dissolved in 3 parts of acetic 

 acid (95%) and warmed with a kvf drops of dilute sulphuric acid 

 (1 : 5) on a water bath until the orange-colored solution becomes al- 

 most colorless. On diluting with water a pale yellow substance sepa- 

 rates out in oily drops, which soon solidify to a white crystalline solid. 

 The yield is almost quantitative, and after crystallizing from a mixture 

 of chloroform and ether the substance was analyzed with the following 

 result. 



0.2010 gram substance dried in vacuum gave 0.3G41 gram CO2 and 



0.074 G gram H2O. 

 0.2 11 2 gram substance dried in vacuum gave 0.1369 gr. AgCl (Carius). 



