JACKSON AND GRINDLEY. — ACETALS FROM QUINONES. 439 



•would be converted into a secondary alcohol by reducing agents, and 

 into an oxime by hydroxylamiue. The reducing agent selected was 

 a mixture of zinc dust and glacial acetic acid, as this had proved 

 rather the most effective for the conversion of a quinone into a hydro- 

 quinone, and there was little or no danger that it would saponify the 

 compound. Even after long continued action there were no signs of 

 reduction, but the unaltered dichlordiethoxyquinone dihenzoyldiethyl- 

 acetal was recovered from the mixture. This experiment, therefore, 

 goes to prove that the substance is an acetal, and this proof is strength- 

 ened by the fact that dichlordiethoxyquinone is converted into the 

 corresponding hydroquinone quickly and easily by this reducing mix- 

 ture. 



To try the action of hydroxylamine 0.2 gram of the dichlordiethoxy- 

 quinone dibenzoyhliethylacetal dissolved in alcohol was mixed with 

 an alcoholic solution of 0.5 gram of hydroxylamine chloride. The 

 solution was boiled over the free flame for half an hour, and then after 

 cooling treated with a large excess of water. The precipitate thus 

 formed after one crystallization from alcohol melted at 170°, and was 

 therefore the unchanged original substance. No other organic sub- 

 stance could be found in the precipitate, or in the aqueous filtrate. 

 The experiment was repeated with an alkaline solution, and again 

 with an acid solution, but in no case could any change in the original 

 acetal be detected. To prove that the indifference of the acetal to the 

 hydroxylamine was not due to the effect of the ethoxy radicals and 

 chlorine atoms attached to its benzol ring, we next studied the action 

 of the chloride of hydroxylamine on dichlordiethoxyquinone. For 

 this purpose 0.5 gram of it were treated with the chlori<le of hydrox- 

 ylamine in alcoholic solution, and the mixture warmed for sixteen hours 

 on the water bath. Water precipitated a black substance crystallized 

 in scales, which was thoroughly washed with water to remove all the 

 hydroxylamine salt. It dissolved easily in sodic hydrate, and from 

 this solution acids threw down a reddish gelatinous precipitate. It 

 gave a good test for nitrogen by the potassium method. There can 

 be no doubt, therefore, that the chloride of hydroxylamine acts on 

 dichlordiethoxyquinone and consequently the indifference of our acetal 

 to this reagent is not due to the presence of the radicals attached to 

 the benzol ring, but is caused by the occupation of the two carbonyl 

 groups by the ethoxy and benzoyl radicals. As we had accomplished 

 our purpose when we had proved that the chloride of hydroxylamine 

 acts on dichlordiethoxyquinone, we have not tried to study the product 

 more carefully. 



