Algar — Diketones from Diacetoresorcinol-Dhnethylether. 87 



derivatives. The amount of the substance obtained was, however, insufficient 

 to allow of further examination. 



Heywang and von Kostanecki (Ber., 35, 1902, p. 2887) condensed 

 o-hydroxyacetophenone with oxalic ester by means of sodium, and on hearing 

 the oily diketone thus formed with alcoholic hydrochloric acid they obtained 

 chromone. In order to prepare dichromone this reaction was tried, usins 

 diacetoresorcinol instead of o-hydroxyacetophenone. The reaction was tried 

 under various conditions, but no indication of the formation of a diketone 

 was obtained, diacetoresorcinol being recovered unchanged. 



Of the diketones described in this paper diacetylaceto-resorcinol- 

 dimethylether and di-a-phenylacetylaceto-resorcinol-dimethylether ai-e colour- 

 less compounds ; dianisoylaceto-resoreinol-dimethylether is coloured slightly 

 yellow, but dimethoxy-isophthaloyl-dipyruvic ethyl ester, in which the 

 methyl, anisyl, and benzyl radicals of the former compounds are replaced 

 by the more acidic carboxyl radical, has a strong yellow colour. 



Experimental Part. 



Bianisoylaceto-rcsorcinol-dimethylether. 



CHsO /\ OCH3 

 CH3O ■ CsHi • CO • CHs • CO I I CO • CHj ■ CO • CsHi • OCH3 



Eight grams of diacetoresorcinol-dimethylether were dissolved with 

 warming in 84 grams of anisic methyl ester, and 3*5 grams of sodium were 

 added. When the reaction had subsided, the mixture was heated in an oil- 

 bath at 120-130° C. for twenty minutes, and then allowed to stand overnight. 

 Excess of sodium was removed with moist ether and water added to dissolve 

 the sodium salt of the diketone. The aqueous layer was separated, and carbon 

 dioxide was passed through it. The small amount of yellow solid which was 

 precipitated was filtered, washed with water, and crystallized from a mixture 

 of chloroform and alcohol, and also from xylol. 



On analysis it gave the following results : — 



0-1429 substance gave 0-3567 CO, and 0-0727 H2O 

 corresponding to C 68-07, H 5-65 

 CosHjsOs requires C 68-54, H 5-34. 

 The substance analysed contained a small amount of ash. 



Dianisoylaceto-resorcinol-dimethylether crystallizes from boiling xylol in 

 light- yellow prisms, which melt at 232-234° C. It is insoluble in cold 

 alcohol and acetone, somewhat soluble in cold chloroform and hot alcohol, 



E.I.A. PROC, VOL. XXXIII., SECT. B. [~0] 



