urbaf2

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NITRO DERIVATIVES OF BENZENE^259

1,2,4,5-Tetranitrobenzene. This compound forms bright yellow crystals. It was

prepared by Borsche and Feske [62] by the action of concentrated nitric acid on

1,3-dinitro-4,6-dihydroxylaminobenzene :

HEXANITROBENZENE

During World War II a method of synthesis of hexanitrobenzene was suggested

in Germany, and the product was supposed to be manufactured on a semi-industrial

scale according to the following scheme:

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No details of this method are available.

Hexanitrobenzene is not stable enough for practical application, as it decom-

poses in the presence of moisture to form trinitrophloroglucinol.

THERMOCHEMICAL PROPERTIES OF NITRO DERIVATIVES

OF BENZENE

The values of the heats of formation of benzene derivatives, given below, have

been calculated from the corresponding heats of combustion (Table 44, Fig. 50).

On the basis of the above values, Garner and Abernethy [50] have calculated

the corresponding heats of nitration (Table 45, Fig. 50). They have also determined

the heats of crystallization, viz., for nitrobenzene they found a value of 2.78 kcal/mole,

and for m- dinitrobenzene, 4.87 kcal/mole.