310 PROCEEDINGS OF THE AMERICAN ACADEMY 



The benzofurfuran derivative is insoluble in water, but, since it con- 

 tains a phenol group, soluble in alkalies. It is easily soluble in most 

 organic solvents except petrolic ether. Warmed with concentrated 

 sulphuric acid, it gives a reddish purple color. 



The question now arises how the formation of the condensation pro- 

 ducts CigHigOe and C12H12O4 can be explained. Sarauw * has shown 

 that, when quinone is treated with hydrobromic acid, hydroquinoue 

 and mono- and di-bromhydroquinone are found. 



Since Nef f has unquestionably proved the presence of two double 

 bonds in quinone, 



CH-CO-CH 



II II 



CH-CO-CH, 



it is highly probable that the action of the hydrobromic acid is to form 

 addition products,t 



(I) 



and that these are then converted into monobrom- and jo-dibrom- 

 hydroquinone respectively, two of the hydrogen atoms in the addi- 

 tion product II. being removed by quinone, which goes over into 

 hydroquinone. 



It is becoming more and more apparent that all the reactions shown 

 by quinone which have hitherto not been understood are due to the 

 ease with which such addition takes place ; the activity of the double 

 bonds in quinone has been further shown above by the addition of 

 bromine and of water to jo-dichlorquinonediacetoacetic ether. It is 

 therefore very probable that acetoacetic ether reacts on quinone, just 

 as hydrobromic acid, forming at first addition products : 



/H /^COH-CHg 



,j . HC-CO-C C-COaCoHg 



(I.) 2 . 5 



HC-CO-C Ha 



* Ann. Cliem. (Liebig), CCIX. 99. 



t Anier. Chem. Journal, XII. 48.3, XIII. 422. 



t Amer. Chem. Journal, XIII. 427. 



