182 Proceedings of the Royal Irish Academy. 



mediate compound in the preparation of piperonylidene-3.4. dimethoxy-3'.4'. 

 methylenedioxy-flavanone, and can be separated from the latter by taking 

 advantage of its greater solubility in alcohol, and also by its solubility in 

 warm dilute potash. 



It was dissolved in chloroform and extracted from the solution by shaking 

 with warm dilute alkali. Hydrochloric acid was added to the orange-yellow 

 alkaline extract, and the solid which separated was extracted with chloro- 

 form. After evaporation of the solvent the residue was recrystallized from 

 boiling alcohol. 



When dried at 105 : C, it melted at 174-176° C, and gave on analysis the 

 following results : — 



0-1517 substance gave 0-3642 CO : and 0-0616 H 2 0. 

 corresponding to C 65 - 5, H 4'54, 

 C 19 H 16 6 requires C 658, H 49. 



PipcronyUdcw-galhicetophcit'jn.-fUnntliiilcthei- crystallizes in yellow prisms, 

 which are somewhat soluble in cold alcohol or ether, readily soluble in 

 benzene, and very soluble in chloroform. 



An alcoholic solution of the substance gave a red coloration with ferric- 

 chloride. 



Crystals of the substance dissolve in concentrated sulphuric acid, forming 

 an orange solution. 



(b) Piperonylidene-gallacetophenone-dimethylether was also obtained by 

 the action of 2 ccs. of 50 per cent, sodium hydrate on a solution of 2 grammes 

 of piperonal and 1 gramme of gallacetophenone-dimethylether in 10 ccs. of 

 alcohol. The product of the reaction was dissolved in warm, dilute, aqueous 

 potash. The alkaline solution was washed with ether, and after separation 

 was acidified by addition of dilute hydrochloric acid. After a couple of 

 recrystallizations from alcohol it melted at 174-176° C. 



C. Condensation "/" a-JHbenzylidene-IHaceto-lieso'rcinol with Aldehydes in the 

 presi nee of Hydrochloric Acid. 



1 3. Dibe nzyl ide a c-difla va none. 



About 40 ccs. of alcohol saturated with gaseous hydrochloric acid were 

 added to a solution of 2 grammes of a-dibenzylidene-diacetoresorcinol and 

 4 ccs. of benzaldehyde in 60 ccs. of chloroform. The mixture, which turned 

 a red colour, was let stand a few- days, and then warmed on the water-bath 

 for a short time. On allowing the solvent to evaporate, a crystalline residue 

 was left. The latter was washed with alcoholic potash, and then recrystallized 

 a few times from chloroform and alcohol. When dried at 105° C, it melted 

 at 268-270= C. 



