Ryan and O'Neill — Studies in the Diflavone Group. 179 



form, and the solution was shaken with warm dilute potash. As the yellowish 

 potash solution on acidification gave only a small precipitate, the chloroform 

 solution was passed through a dry filter paper, concentrated, and mixed with 

 an equal volume of absolute alcohol. The solid which separated was filtered 

 and boiled for a short time with pyridine, in which it dissolved readily. The 

 substance was reprecipitated from the pyridine solution by addition of xylene, 

 and recrystallized, first from xylene, afterwards from benzene. After 

 drying at 106° C. it melted at 240-242° 0., and gave on analysis the 

 following results : — 



OT550 substance gave 0-3921 CO, and 0-0515 H 2 

 corresponding to C 69'0 H 3'7 

 C S4 H 22 O 10 requires C 69T5 H 3-7. 



Piperonylidene-3 . aceto-4 hydrozy-piperonylidene-3' .4,' . methylenedioxy-flava- 

 none crystallizes from benzene in small yellow prisms, which are insoluble in 

 cold alcohol, ether, or ligro'in, sparingly soluble in cold benzene or xylene, 

 soluble in hot benzene, and readily soluble in warm chloroform. 



On addition of ferric chloride to a suspension of the substance in boiling 

 alcohol, no coloration was produced. 



The crystals are turned a dark bluish-red colour by contact with 

 concentrated sulphuric acid, in which they dissolve to a cherry-red 

 solution. 



As the compound is nearly insoluble in hot dilute alkali, and as it, when 

 suspended in boiling alcohol, gives no coloration with ferric chloride, it would 

 seem to be a diflavanone derivative, having the formula : — 



CH:0:CHCH XT C 





^CH-CH: 0:CH 



2 2 6 3 1 1 vm II 



63 2 2 



CH C. C 



C:CH-CH:0:CH 

 ' 6 3 2 2 



rather than a chalkone-flavanone with the formula ascribed to it above. 



Since ortho-hydroxy-chalkones are often sparingly soluble in alkali, and 

 since our compound is so slightly soluble in alcohol that a marked coloration 

 with ferric chloride could scarcely be expected in alcoholic solution, we do not 

 consider the behaviour of the substance towards dilute alkali and ferric 

 chloride sufficiently strong grounds for proposing the diflavanone formula for 

 the substance. If the compound were a diflavanone, we should expect from 

 analogy with the monoflavanones that it would be completely or nearly 

 colourless, and that its bromo-derivative should be easily convertible into 

 a diflavone. 



