The Chemistry of Powder and Explosives - Sciencemadness Dot Org

216 NITRIC ESTERS
soluble in alcohol, ether, acetone, and chloroform, somewhat less
soluble than nitroglycerin in benzene, and insoluble in carbon
tetrachloride and ligroin. It consists of a mixture of the two possible
structural isomers, the 1,2- or a,/3-dinitrate, known also as
"dinitroglycerin F," and the 1,3- or a,a'-dinitrate or "dinitroglycerin
K." Both are uncrystallizable oils, and both are hygroscopic
and take up about 3% of their weight of moisture from the aiiL,
They are separated by virtue of the fact that'the a,a'-dinitrate
forms a hydrate 31 with one-third of a molecule of water,
C3H8O7N2 + % H2O, water-clear prisms, m.p. 26°. No hydrate
of the a,/3-dinitrate has ever been isolated in the state of a crystalline
solid. If a test portion of the moist mixture of the isomers
is mixed with fuller's earth and chilled strongly, it deposits
crystals; and if these are used for seeding the principal quantity
of the moist dinitroglycerin, then the hydrate of the a,a'-dinitrate
crystallizes out. It may be recrystallized from water, or from
alcohol, ether, or benzene without losing its water of crystallization,
but it yields the anhydrous a,a'-dinitrate if it is dried over
sulfuric acid or warmed in the air at 40°.
The chemical relationships between the mononitroglycerins and
dinitroglycerins supply all the evidence which is needed for inferring
the identities of the isomers. Of the two rnononitrates, the
/3-compound obviously cannot yield any