( 463 ) 
It also appears that the stability of the amides and methylamides 
of the different chloro-nitrobenzoie acids when in contact with nitric 
acid at zero is not the same. The most unstable are the derivatives 
of 4 chlorine- 3 uitrobenzoie acid which according to BETHMANN is 
the weakest of the three chlero-nitrobenzoic acids. It is remarkable 
that this acid is the only one of the three where none of the groups 
is in ortho-position with the side chain, and the slow action of nitric 
acid on the amides of the two others may perhaps be to some extent 
ascribed to the ortho-position of chlorine- or nitro-group, or in 
other words to “sterical obstacle”. From the methylamides of 3 
chlorine- 6 nitro- and of 4 chlorine- 3 nitro-benzoic acid, a methyl- 
nitramide was obtained, but none was got from 2 chlorine- 5 nitro- 
benzoic acid the only compound in which the chlorine is in the 
ortho position. 
The result of the action of nitric acid at the ordinary temperature 
on the amides and their niethyl derivatives was that the amides 
yielded, as usual, nitrous oxide and nitro-acid whilst the methyl- 
amides yielded nitrous oxide, methyl nitrate and nitro-acid; the 
dimethyl amides yielded nitro-acid and dimethylnitramine. The nitro- 
acids of the o- and m-derivatives appeared to contain a small quan- 
tity of an isomeric body. This result differs from that obtained by 
TAVERNE with the derivatives of phenylacetic and pheny!propionic 
acid which yielded a dinitro acid. The difference in stability towards 
nitric acid was here also apparent; and as regards the dimethyla- 
mides, a littie secondary action took place, presumably oxidation 
of one of the methylgroups and formation of a methyl nitramide. 
The dissertation also contains a table of melting points of the 
compounds described. It will be noticed that, as is generally the 
case, the melting points of the chlorides and methyl esters are lower 
than those of the acids and those of the amides either higher or 
lower; but those of the mono-methylamides are lower than those 
of the amides and those of the dimethylamides are lower still. 
MELTING POINTS. 
ortho-comp. meta-comp. para-comp. 
chloro-benzoic acid 140° 158° 236°.5 
chloride — 4° liquid |B 
methyl ester liquid 21° 43° 
amide 141° 1342.5 179° 
mono-metbylamide 121°.5 Epe ToL 
dimethylamide 13°.5 61° 59° 
