THE GRIGNAKD REAGENT ON O-PHTHALIC ESTERS. 13 



each drop of the ester, in the early stage of the reaction, pro- 

 ducing a hissing sound, and causing the Grignard reagent to 

 splash, as it dropped into the latter. The reaction, however, 

 became quite mild as it went on, and ultimately some yellowish 

 substance precipitated out. 



The whole was decomposed as before by means of ice and 

 dilute sulphuric acid, when a considerable quantity of a white 

 crystalline substance was obtained. It was found to be insoluble 

 in water, alcohol, ether, or petroleum ether, moderately soluble 

 in benzene and very easily soluble in chloroform, and could, 

 therefore, be conveniently recrystallised from a mixture of 

 chloroform and ether. Thus purified, it w^as obtained in the 

 form of colourless small needles of melting point 207°, Its pro- 

 perties agreed well with the description given by H. Bauer^^ of 

 dibenzyl-phthalide, except that he gives 204° as its melting point. 

 An analysis of the substance, which gave the following results, 

 has, moreover, left no doubt as to its being dibenzyl-phthalide : 



0.1502 g. of the substance gave 0.4634 g. of COo and 



0.0795 g. of HoO, therefore 



C=84.14 H=5.92. 



Dibenzyl-phthalide, CgHZ ^O, requires 



^CO — ^ 



C=84.02 H=5.79. 



On distilling off ether from the ethereal solution separated 



from the aqueous layer and the crystals of dibenzyl-phthalide, a 



brownish oil was left behind, w^hich solidified to a colourless 



crystalline mass, when left for some time in a vacuum. It was 



dried on a porous porcelain plate and then recrystallised from a 



1) Ber., (1905), 38, 240 



