190 Proceedings of the Royal Irish Academy. 



which melted at 195°-196°C. A mixture of it with a-dianisylidene- 

 diacetoresoreinol melted between 170° and 190° 0. 



0-1505 substance gave 0-4003 C0 2 and 0-0726 H 2 

 corresponding to C 72-54, H 5 - 35 

 C M H 23 6 requires C 72-55, H 511. 



fi-Dianisylidene-diacetoresorcinol is soluble in cold chloroform or hot 

 benzene, and almost insoluble in cold alcohol. 



Concentrated sulphuric acid dissolves the substance, forming a bright-red 

 solution. 



A solution of it in hot alcohol is coloured a brownish-red by ferric 

 chloride. 



B. Dianisylidene-Dicoumaranone. 



5. Tetrabromidc of Dianisylidene-diacetoresorcinol-diacetate (VIII). 



CH 3 . COO /\ OOC . CH 3 

 CH 3 . C 6 H 4 . CHBr . CHBr . CO '""' CO . CHBr . CHBr . C fl H 4 . OCH 3 



A mixture of 2 grams of &-dianisylidene-diacetoresorcinol, 2 grams of 

 anhydrous sodium acetate, and 20 c.cs. of acetic anhydride was heated to 

 gentle boiling on a sand-bath, and was then allowed to cool slowly ; water 

 was added, and the mixture was let stand for a couple of hours. The aqueous 

 layer was decanted, the residue was shaken with dilute sodium carbonate, 

 and extracted with ether. The ether solution was dried with calcium 

 chloride, filtered, and after evaporation of the ether a yellow, oily residue 

 was obtained. 



The oily diacetate was dissolved in a small quantity of chloroform, and 

 the theoretical amount of bromine was added to this solution. After standing 

 for several hours most of the chloroform was evaporated, and alcohol was 

 added to the residue. A colourless amorphous compound was precipitated. 

 As repeated efforts to crystallize it were unsuccessful, we converted it by 

 interaction with alcoholic potash into dianisylidene-dicoumaranone. 



6. Dianisylidene-dicoumaranone (III). 



To an alcoholic solution of the tetrabromide of the diacetate prepared 

 from 3 grams of a-dianisylidene-diacetoresorcinol 84 c.cs. (6 mols.) of semi- 

 normal alcoholic potash were added, and the mixture was heated on the water- 

 bath for five minutes. The solution, which darkened in colour with separation 

 of a brownish-yellow solid, was cooled and filtered. The residue was washed 



