JACKSON AND GRINDLEY. — ACETALS FROM QUINONES. 433 



Found. 



U. 



19.78 



These results show that the action of the sodic ethylate on the 

 dichlordiphenoxyquinone is analogous to that of sodic methylate, since 

 two phenoxy groups are replaced by two ethoxy groups, and then two 

 molecules of sodic ethylate are added directly to one molecule of the 

 dichlordietlioxy(|uinone thus formed, giving the sodium salt of dichlor- 

 diethoxyquinone diethylhemiacetal. The yield of the sodium salt from 

 10 grams of dichlordiphenoxyquinone was usually a little less than 

 10 grams, and therefore, as the change from the sodium salt to the 

 hemiacetal is nearly quantitative, we obtained over 75 per cent of the 

 theoretical yield. 



Properties of the Dichlordiethoxyquinone Diethylhemiacetal. — It is 

 a white amorphous solid, which dissolves slightly in alcohol, but is 

 partially decom[)psed by this solvent, so that it cannot be recrystallized 

 from it. It is essentially insoluble in all the other common solvents. 

 By boiling with dilute sulphuric or hydrochloric acid it is decomposed, 

 and the same reaction takes place more slowly when it stands with 

 the dilute acid in tlie cold. The product of the action in either case 

 is a light red body melting at 104° -105°, after being purified by crys- 

 tallization from alcohol, which is, therefore, dichlordiethoxyquinone, 

 as this is the melting point ascribed to this substance by Kehrmann.* 

 Stenhouse,t who discovered it, gives its melting point as 107° ; but 

 even by repeated recrystallization we have not been able to raise the 

 melting point above 104°-105°, and therefore have come to the con- 

 clusion that Stenhouse's higher number must be due to an error. The 

 white insoluble hemiacetal melts at 140°-143°, or rather decomposes 

 at this temperature, changing into the red dichlordiethoxyquinone, 

 which then melts. From these properties it appears that the relation- 

 ship between the diethyl and dimethyihemiacetals is of the closest 

 sort. 



Like the corresponding methyl compound the dichlordiethoxyqui- 

 none diethylhemiacetal has acid properties forming with sodic hydrate 

 a sodium salt. It shows toward sodic hydrate a stability in marked 

 contrast to its susceptibility to the action of dilute acids, as it is neces- 



* Journ. Prakt. Chem., [2 ], XL. 365. t Ann. Cliera., Suppl. VIII. 14. 



VOL. XXX. (n. S. XXII.) 28 



