The Chemistry of Powder and Explosives - Sciencemadness Dot Org

TETRYL 179
m-nitrotetryl is effectively removed from crude tetryl by boiling
the finely powdered solid with water.
Crude tetryl commonly contains a small quantity of amorphous-appearing,
buff-colored material of high melting point
which is insoluble in benzene. The amount of this material is
increased by the presence of larger amounts of water in the
nitrating acid. Michler and Pattinson 88 found that tetramethylbenzidine
is produced when dimethylaniline is heated with concentrated
sulfuric acid. The same material is evidently formed
during the preparation of tetryl and gives rise to the three substances
indicated below, which constitute the benzene-insoluble
impurity.
NO,
CHS
NO, NO,
NO, NO,
NO,
These substances were prepared by Mertens 89 in 1886 by the
action of nitric acid on dimethylaniline (I, II, and III) and on
monomethylaniline (II and III). Van Romburgh 90 in the same
year proved them to be derivatives of benzidine, and at a much
later time 91 summarized the work which had been done upon
them and synthesized the substances in such manner as to prove
the position of the nitro groups.
88 Ber., 14, 2161 (1881).
89 Loc.cit.
MRec. trav. chim., 5, 240 (1886).
91 Ibid., 41, 38 (1922).