( 478 ) 
Chemistry. — Prof. C. A. Lopry DE BRUYN presents a communication 
from Prof. A. F. HorLLEMAN: “The formation of trisubsti- 
tuted derivatives from di-substituted derivatives of Benzene.” 
(Read February 24, 1900.) 
As stated last year (in the Recueil) *) benzoic acid when nitrated at 
0° yields the three possible isomers in the proportion of : 
18.5 ortho : 80.2 meta : 1.3 para. 
Jointly with Mr. B. R. pe Bruyy, I have now found that 
on nitrating nitro-benzene at 0°, the three isomers are formed in the 
proportion of: 
6.4 ortho : 93.5 meta : 0.1 para 
at all events the amount of the para-compound was less than 0.2. 
If one now examines, as far as is possible at the present time 
what relative proportions of the isomeric dinitroacids have been obtai- 
ned by nitrating the mono-nitrobenzoic acids it appears that the 
compounds obtained in largest quantity are those for which the products 
of the above relative numbers are greatest. 
In the nitration of o-nitrobenzoic acid the products for the still 
unoccupied places in the benzene nucleus are given in the formula below : 
CO, H 
“The highest figure is, therefore, in 6; acid in 
fact, the acid 1: 2:6 is the chief product. 
3) 504 
100 
CO, H 
1 
. . ; . 3 6 2/ 118 
In the nitration of m-nitrobenzoic acid the 
products for the still unoccupied places are: 
7499 |9 IN Oa 
4 
8 
) Proceedings 1899, 
