304 THE ACTION OF ORG A NO-MAGNESIUM COMPOUNDS 



duction products of the reaction. It was fairly large in 

 quantity, but it was not practicable to isolate any other pure 

 product from it. 



Quinone and Ethylmagnesium Bromide. 

 An ethereal solution of 11 grams of quinone was added 

 gradually, 5 c.c. at a time, to a solution of ethylmagnesium 

 bromide obtained by dissolving 5 grams of magnesium ribbon 

 in 25 grams of ethyl bromide and 50 grams of absolute ether. 

 To ensure a more complete reaction, the mixture was allowed 

 to stand a day with occasional shaking. The blue reaction 

 product which separated out insoluble in ether, was treated 

 with ice water and acidified with dilute hydrochloric acid. The 

 addition of water turned the mixture green, while a further 

 addition of acid turned it brown, separating out at the same 

 time, as in the case of the methyl iodide compound, a brown 

 precipitate insoluble in ether or water. It was observed that 

 although the ethylmagnesium bromide quinone compound was 

 blue, the mixture, after the addition of water, was green 

 and that no such change of colour was noticed with the iodide 

 quinone compound. This was probably due to the, fact that 

 both the iodide quinone compound and its products of decom- 

 position were green. Moreover, it was found that the amor- 

 phous precipitate, insoluble in ether, was readily soluble in 

 alkalis, producing a green solution"; and since magnesium 

 hydroxide, which would be produced by the addition of water, 

 is slightly soluble in water, it would dissolve enough of the 

 substance to colour the mixture green. 



The acidified mixture was then filtered and the amorphous 

 precipitate remaining on the filter paper was washed with 

 dilute hydrochloric acid and then with ether and dried. The 

 ethereal solution was next separated and the water solution 

 further extracted with ether. On a partial evaporation of the 

 ether a solid separated, which was filtered and recrystallized 

 from ether. The substance gave practically a constant melt- 



