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96 CHEMISTRY AND TECHNOLOGY OF EXPLOSIVES

Hass, Dorsky and Hodge [67] nitrated paraffins with nitrogen dioxide under

pressure. They were able to nitrate methane to nitromethane.

Levy and Rose [68] reported that nitration of propane with nitrogen dioxide

at 360°C under 10 atm gave a 75-80% yield of nitroparaffins. The mixture of

products was composed of 20-25% nitromethane, 5-10% nitroethane, 45-55%

2-nitropropane, 20% 1-nitropropane and 1% 2,2-dinitropropane. Geiseler [69]

nitrated paraffins under 4 atm at 190°C. Grundman and Haldenwanger [70] nitrated

cyclohexane with nitrogen dioxide at 120-125°C under 4-5 atm and obtained both

mono- and di-nitroproducts.

Titov [71] in 1948, carried out an extensive study on the nitration of aliphatic

side-chain of aryl-aliphatic hydrocarbons with nitrogen dioxide. He found that,

for example, the nitration of toluene may result in the formation of phenyldinitro-

methane along with phenylnitromethane. Low temperature facilitates the formation

of the former (Table 13).

TABLE 13

RESULTS OF NITRATION OF 1000 ml OF TOLUENE WITH NITROGEN DIOXIDE AT DIFFERENT

TEMPERATURES

Nitration temperature

°C

20

70

95

Quantity of phenylnitro- Quantity of phenyldinitro-

methane obtained methane obtained

g g

23.5 5.0

6.8 15.9

1.4 13.4

According to Titov the formation of phenyldinitromethane may be presented

by the scheme:

NO 2 NO N 2 O 4

C 6 H 5 CH 3 -> C 6 H 5 CH 2. -> C 6 H 5 CH 2 NO -> C 6 H 6 CH = NOH -> C 6 H 5 CH(NO 2 ) 2

Unsaturated hydrocarbons

When olefin hydrocarbons react with nitrogen dioxide or nitrous and nitric

anhydride they are added to a double bond. For the reactions of N 2 O 5 and N 2 O 3

see also pp. 106 and 109.

The addition of nitrous anhydride results in the formation of nitrosites (nitroso-

nitrites) (I) :

By the addition of nitrogen dioxide, nitrosates (II) (nitroso-nitrates) or dinitro
compounds (III) or dinitrites (IV) are obtained. Nitrosates (II) can be oxidized

to nitro-nitrates (IIa).