OP ARTS AND SCIENCES. 



305 



The substance melts at 171° to a pale yellow liquid, and sublimes 

 without decomposition. It crystallizes in star-shaped leaflets or short 

 prisms, and is easily soluble in organic solvents, but insoluble in water 

 or mild alkalies. Warmed with concentrated sulphuric acid it gives 

 a deep bluish green coloration, which is characteristic for furfuran 

 derivatives. 



Treated with twice the calculated amount of alcoholic potash, it is 

 saponified to a dibasic acid, ChHioCLOs, which crystallizes from hot 

 water in colorless needles. The acid is best purified by dissolving in 

 soda and addition of dilute acids, when it separates out very slowly on 

 standing. It decomposes with evolution of carbon dioxide on heat- 

 ing to 220°. An analysis gave results which agree closely with the 

 formula C14H10CI2O8, but show that the acid was not quite pure. 

 (Found 43.53% C, 2.96% H, 20.50% CI. Theory, 44.56% C, 

 2.65 % H, 18.95 % CI.) 



The formation of the above ester, CigHigClaOs, isomeric with p-di- 

 chlorquinonediacetoacetic ether is probably as follows. At first, an 

 addition of two molecules of water takes place, just as has been ob- 

 served in the case of many olefine derivatives: 



O 



CH3-C OH CI 

 CO2C2H5C 



-C-CO.,CoH 



2"5 



+ 2HoO 



CI HO C-CH, 



O 



p-Dichlorquinonediacetoacetic Ether. 



CH3-C OH 

 COAH5-C 



VOL. XXTI. (X. S. XVIII. 



Cl\ 



HO/ 

 H\ 



O 



NH 



O 



Addition Product. 

 20 



-C-CO,C,R 



2'-'2i»6 



/OH HOC-CH3 

 \C1 



