The Chemistry of Powder and Explosives - Sciencemadness Dot Org

TRINITROANISOL AND TRINITROPHENETOL 171
chloride, treated with an excess of sodium methylate or of strong
caustic soda solution, turns dark red and deposits handsome
brilliant red crystals of the empirical composition, trinitroanisol-NaOCH3.
The probable constitution of these crystals is
indicated below. On treatment with acid the substance yields
trinitroanisol.
LcCNajOCH, CH Q 0CH 0CH.
NO,
+NaC1+CHa0H
The red material is sparingly soluble in alcohol and in water,
and is easily decomposed by aqueous acids. It is a primary explosive,
stable to moderate heating but decomposing at 165° and
exploding violently when introduced into a flame. It is not altered
by dry air, but water decomposes it slowly to form first trinitroanisol
and later picric acid. On boiling with ethyl alcohol, it yields
the sodium ethylate addition product of trinitrophenetol—an
interesting reaction analogous to the ester interchange in the
aliphatic series.
Preparation of Trinitroanisol. Thirty-five grams of picryl chloride is
dissolved in- 400 ec. of methyl alcohol with wanning under reflux, and
the solution is allowed to cool to 30-35°. A solution of 23 grams of
sodium hydroxide in 35 cc. of water is added slowly through the condenser,
while the liquid is cooled, if need be, to prevent it from boiling.
The mixture is allowed to stand for an hour or two. The red precipitate
is filtered off, washed with alcohol, and stirred up with water while
strong hydrochloric acid is added until all red color has disappeared.
The slightly yellowish, almost white, precipitate, washed with water for
the removal of sodium chloride, dried, and recrystallized from methyl
alcohol, yields pale yellow leaflets of trinitroanisol, m.p. 67-68°. From
anhydrous solvents the substance separates in crystals which are practically
white.
Since the methoxy group exercises a greater effect in promoting
substitution than the chlorine Atom does, it is to be expected that
dinitroanisol would take on a third nitro group more easily than
dinitrochlorobenzene (to form picryl chloride), and with less expense
for acid and for heat. The reactions indicated below are
probably the best for the large-scale commercial production of
trinitroanisol.