Nitro-p-dichlorobenzene

Remarks. Nitro-p-dichlorobenzene can be reduced to p-dicbloroaniline in tbe usual way with iron and a small amount of acid. Tbe chlorine ortbo to tbe nitro group is labile and can be replaced by various substituents, less easily, however, than the chlorine in 2,4-dinitrochlorobenzene, but more easity than that in o-nitrochloro-benzene. The replacement of the chlorine by hydrojyl by the action of aqueous sodium hydroxide is described in the following preparation. Reaction wiUi sodium methylate yields 4-chloro-2-nitroanisole, which is reduced to 4-chloro-2-am sidine (chloramsidine P, or fast red R base). With ammonia under pressure, 4-chloro-2-nitroaniline (fast red 3CL base) is formed. These bases are important starting materials for the preparation of azo dyes, especial pigment and lake coIots, as well as ice colors. 

In the explosives industry only the nitro derivatives of p-dichlorobenzene and 1,3,5-trichlorobenzene have gained any importance. 

Mono- and di-nitro derivatives were first obtained by Jungfleisch [9] in 1868. Kijmer [36] demonstrated that the product of dinitration of p- dichlorobenzene consists of the a- and 0- isomers. Morgan and Norman [37] isolated yet another one, the y- isomer. The preparation and properties of all these isomers were investigated by Holleman [38],... 

There are two good routes from 15b to p-phenylenediamine (22), namely reduction with Na2S3 in aqueous solution, and acid/iron reduction. It is also made by the action of ammonia on p-dichlorobenzene under pressure. The p-amino acetanilide (23) is made by reduction of the nitro-precursor 21. 

Trinitro derivatives of chlorobenzene Picryl chloride Physical properties Chemical properties l-Chloro 2,4.5-trinitrobenzene Diagram of the nitration of chlorobenzene Thermochemical and explosive properties of chloronitrobenzenes Nitro derivatives of p-chlorobenzene Mononitro derivative of p-chlorobenzene Dinitro derivative ofp-dichlorobenzene 2,4,6-Trinilroderivativc of L3.5-trichlorobcnzene Manufacture of L3,5-lrichloro-2.4,6-irinitrobenzene Nitro derivatives of fluorobenzene Literature... 

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