The Chemistry of Powder and Explosives - Sciencemadness Dot Org

NITRO DERIVATIVES OF NAPHTHALENE I55
from both the a- and the /3-compounds. After two nitro groups
have been introduced, conflicts of orienting tendencies arise and
polynitro compounds are formed, among others, in which nitro
groups occur ortho and para to one another. Only four nitro
groups can be introduced into naphthalene by direct nitration.
The mononitration of naphthalene takes place easily with a
mixed acid which contains only a slight excess of one equivalent
of HNO3.
For the di-, tri-, and tetranitrations increasingly stronger
acids and higher temperatures are necessary. In the tetranitration
oleum is commonly used and the reaction is carried out at 130°.
The nitration of a-nitronaphthalene 43 (m.p. 59-60°) yields a
mixture of a- or 1,5-dinitronaphthalene (silky needles, m.p. 216°),
/3- or 1,8-dinitronaphthalene (rhombic leaflets, m.p. 170-172°),
and Y- or 1,3-dinitronaphthalene (m.p. 144-145°).
NO, NO2 NO, NO,
-NO,
NO,
a- 0- 7-
The commercial product of the dinitration melts at about 140°,
and consists principally of the a- and /3-compounds. The nitration
of naphthalene at very low temperatures, 44 —50° to —60°,
.gives good yields of the y- compound, and some of this material
is undoubtedly present in the ordinary product.
The nitration of a-dinitronaphthalene yields a- or 1,3,5-trinitronaphthalene
(monoelinic crystals, m.p. .123°), Y- or 1>4,5-
43 Roussin, Comp. rend., 52, 796 (1861); Darmstadter and Wickelhaus,
Ann., 152, 301 (1869); Aguiar, Ber., 2, 220 (1869); 3, 29 (1870); 5, 370
(1872); Beilstein and Kuhlberg, Ann., 169, 86 (1873); Beilstein and
Kurbatow, Ber., 13, 353 (1880); Ann., 202, 219, 224 (1880); Julius, Chem.
Ztg.T 18, 180 (1894); Gassmann, Ber., 29, 1243, 1521 (1896); Friedlander,
ibid., 32, 3531 (1899).
"Pictet, Comp. rend., 116, 815 (1893).