eer. 
( 645 ) 
occupies the para-position, the as yet free ortho-positions get occupied 
by NO, and the hydrogen in combination with the N is replaced 
by NOs. If, however, a COOH-group occupies an ortho- or para- 
position in regard to NHCHs this will then be replaced by Br or NOg. 
If a chlorine or bromine atom occupies the meta-position in regard 
to the NHCHs (obtained by treating chloro- or bromodinitrobenzene | 
with methylamine) these groups will have no influence on the further 
introduction of bromine atoms or nitrogroups. 
We therefore, see: 
1°. That on bromination of methyl-(ethyl) aniline derivatives, 
the free ortho- and para-positions are always occupied by bromine, 
while the hydrogen atom linked at the nitrogen is not attacked. 
The same happens during the nitration but there the hydrogen- 
atom of the NHCH3;-group gets replaced by NO. 
20. that a carboxyl group in an o.- or p.-position is replaced by 
Br or NO, with evolution of CQg. 
3°. that the occupation of the meta-position by other groups 
(NO, Cl, Br, CH3) has no influence on the introduction of bromine 
atoms and nitrogroups in ortho- and para-positions. 
In the previous communication it has already been observed that 
during the bromination and nitration of phenol and aniline deriva- 
tives, the NOg-groups and halogen atoms probably first enter into 
the side chain to shift later on towards the nucleus.') One might 
call this substitution of the hydrogen atoms of the nucleus an 
indirect substitution in contrast to the direct substitution which 
takes place with benzene and substituted benzenes containing the 
groups COOH, Cl, Br, NO,, SOsH, etc. 
We then see that: 
1°. indirect substitution as is well known, takes place very 
readily. Phenol and aniline, for instance, are readily nitrated, or 
brominated by dilute nitric acid or bromine water; the direct sub- 
stitution is much more difficult (nitration of benzene, nitrobenzene, 
chlorobenzene etc.) 
20. during the indirect substitution, the substituents always occupy 
the ortho- and para-positions in regard to the side chain; during 
the direct substitution meta-substitution products are also formed, 
sometimes by preference. 
30, during the indirect substitution it is possible to replace some 
1) Bunge, Anu. Supp. 7. 117. (1869). ArMSTRONG, Soc, 77, 1047. Cuarraway and 
Orton, Soc. 79, 274. 
