10 ART. 4. — Y. SHIBATA : THE ACTION OF 



/C(CHJ, 

 Dimelliyl-plitlialide, CGn4<f >0, requires 



^CO / 



C = 74.03 11 = 6.23. 



Dimethyl-plithalide had been already obtained by R. Kothe,^^ 

 H. Bauer,"^ and others, Bauer having obtained it synthetically 

 from methyl magnesium iodide and phthalic anhydride, and with 

 a much better yield than the others. The description of the 

 substance given by these authors well coincides with the pro- 

 perties of tlie sample prepared by me, except its melting point, 

 that given by Bauer (68-69°) being a degree or two lower. A 

 similar difference in the melting point was also observed in the 

 case of dibenzyl-phthalide to be described hereafter. 



The existence of a double linking in l:l-dimethyl-3-methyl- 

 ene-phthalane was easily proved by the action of bromine upon 

 it, a solution of bromine in chloroform, when added drop by 

 drop to one of the substance in the same solvent, being at once 

 decolourised. When allowed to stand for a while, after a slight 

 excess of bromine had been added, the mixture acquired a deep 

 black colour ; this, however, has not yet been further investigated. 



II. The action of phenyl magnesium bro^nide on o-phthalic 

 acid diethyl ester. 



Precisely as in the preceding case, the phthalic ester and 

 phenyl magnesium bromide, both dissolved in ether, were mixed 

 together in the proportion of 1 to 4 molecules, and the reaction 

 product was decomposed by ice and dilate sulphuric acid. After 

 driving off ether from the ethereal layer, separated from the 

 aqueous solution, there remained a yellowish viscous oil, which 



1) Ann. d. Chem., (1888), 248, 56. 



2) Ber., (1904), 37, 735. 



