Algar — Diketones from Diacetoresorcinol-Dimethylether. 89 



semi-solid brown mass which separated was allowed to stand at the ordinary 

 temperature for twenty-four hours. It was then mixed with ether, and water 

 was added, until a clear, dark-red aqueous layer was obtained. On separating 

 and acidifying it with hydrochloric acid a yellow solid was precipitated 

 which was filtered and dried. It crystallizes from chloroform in colourless 

 prisms which melt at 116-118° C. On analysis it gave the following results : — 



01689 substance gave 0-3891 (JO^ and 0-0928 H2O, 

 corresponding to G 62-81, H 6-10, 

 C.eH.sOe requires C 62-74, H 5-88. 



Diacetylacetoresorcinol-dimetliylether is sparingly soluble in carbon bisul- 

 phide, soluble in benzene, ether, or alcohol, and very soluble in chloroform. 

 Its soliTtion in alcohol gives a dark-red colour with ferric chloride. 



An attempt was made to prepare a dichromone by heating diacetylaceto- 

 resorcinol-dimethylether with hydriodic acid (s.g. 1-7). The reaction was tried 

 under various conditions, but in all cases gave unsatisfactory results. When 

 the diketone was heated for six hours with hydriodic acid, and the oily 

 product purified, an extremely small amount of a colourless su.bstance was 

 isolated, which dissolved in concentrated sulphuric acid forming a colourless 

 solution with an intense green fluorescence. It seems probable, therefore, 

 that this product was a dichromone, but the quantity formed was too small 

 to admit of examination. 



Dimethoxy-isophthaloyl-di'pyruvic ethyl ester. 



CH2O /\ OCH3 



C2H5OOC ■ CO • CH2 • CO II CO • CH2 • CO • COOC2H5 



10 grams of diacetoresorcinol-dimethylether were dissolved with heating 

 in 100 CCS. of diethyl oxalate. The solution was cooled, and 4-2 grams of 

 sodium wire were added. When the reaction had subsided, the mixture was 

 warmed in an oil bath to 120'' C. for fifteen minutes, and then allowed to 

 stand in a stoppered flask for twelve hours. A brown solid separated, from 

 which excess of sodium was removed with moist ether. Water was then 

 added to dissolve the sodium derivative of the diketone. The alkaline 

 solution was separated from the ether and acidified. The yellow solid which 

 separated was filtered and crystallized from a mixture of chloroform and 

 alcohol. 



On analysis it gave the following results : — 



0-1528 substance gave 0-3179 GO, and 0-0749 H^O 

 corresponding to C 56-74, H 5-44 

 CViHa^Oio requires G 56-87, H 5-21. 



