Algar — Unsaturated Ketones derived from Diaceto-Orcinol. 113 



chloride. On evaporation of the ether, diaceto-orcinol-dimethylether remained 

 behind as a eoloui-less oil. It was purified by distillation in vacuo ; — 



0-1645 substance gave 0'3988 COo and 0-1031 H^O 

 corresponding to C 66-11, H 6-96 

 CsH.eOi requires C 66-10, H 6-78. 



Biaceto-orcinol-dimethylether is a colourless oil which boils at 195-197° C. 

 under 30 mms. pressure. It is insoluble in water, but easily soluble in 

 alcohol, acetone, ether, chloroform, or benzene. A solution of the substance 

 in alcohol gave no coloration with ferric chloride. 



Dibenzylidene-diaceto-orcinol. 



CO . CH : CH . CsHs 

 HO/\OH 



\/C0 . CH : CH . CsHs 

 CH3 



About 12 CCS. of 50 per cent, sodium hydroxide were added, drop by drop, . 

 to a solution of 4 grams of diaceto-orcinol, and 10 c.cs. of benzaldehyde 

 in 100 c.cs. of boiling alcohol, and the mixture heated for about 45 minutes. 

 When the liquid was cooled no solid was precipitated, but on addition of 

 alcoholic hydi'ochloric acid a yellow solid separated out. This substance was 

 filtered, washed with water and alcohol, and purified by dissolving it in 

 acetone and reprecipitating it with alcohol. In this manner a light yellow 

 non-crystalline substance was obtained. Efforts to obtain it in a crystalline 

 condition were unsuccessful : — 



0-1594 substance gave 0'4567 CO2 and 0-0812 H.O 

 corresponding to C 78-13, H 5-66 

 CosHjA requires C 78-12, H 5-21. 



Dibenzylidene-diaceto-oninol is an amorphous light-yellow solid which melts 

 about 143-153° C, and is almost insoluble in alcohol, easily soluble in ether 

 chloroform, acetone, or benzene It dissolves in concentrated sulphuric acid, 

 forming an orange-red solution. Ferric chloride colours its alcoholic solution 

 brown. 



Dianisylidene- diaceto-orcinol. 



CO . CH : CH . CsH, . OCH3 

 HO/\OH 



II 



\/C0 . CH : CH . CgHi . OCH3 

 CHs 



To a solution of 4 grams of diaceto-orcinol, and 10 c.cs. of anisaldehyde in 



