412 



The Philijjpine Journal of Science 



1913 



DIPHTHALYL 



c=o 



C 6 H 4 <^ ^>0 



a ** 



.2 o 



■5 £ 

 u 



c 



C 6 H 4 ^ ^> 



c=o 



Oscillation frequency. 

 24 2 6 28 3000 3 2 34 36 38 4000 42 44 



U 1 



2>^ \ . 



14 

 2.2 

 2.0 

 1.6 

 1.6 

 1.4 

 IZ 

 1.0 



Fig. 11. Curve 1. Diphthalyl in glacial acetic acid. Curve 2. Diphthalyl in sulphuric 



acid. 



Diphthalyl was made by reducing phthalic anhydride in 

 glacial acetic acid solution with zinc dust. 9 It was recrystal- 

 lized from glacial acetic acid after boiling with bone black until 

 colorless. The glacial acetic acid solution is colorless, and shows 

 1 



a band at 



2880 accompanied by a shallow band at about 



= 3200 (fig. 11). 

 The sulphuric acid solution is light yellow with bluish 



'Ibid. (1884), 17, pt. 2, 2178. 



