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594 CHEMISTRY AND TECHNOLOGY OF EXPLOSIVES

of 15-20°C, maintained by cooling and stirring. The rise of temperature may have

been due to breakdown of the stirring equipment. It was also suggested that the

presence of iron oxide or some other catalyst may have sensitized the mixture or

promoted it to a “wild” side-reaction.

Tetranitromethane may also be obtained by reacting nitric acid with ketene

(which may be regarded as a kind of acetic anhydride), according to d’Arsens and

G. Levy [70].

Tetranitromethane is also formed during the nitration of aromatic hydrocarbons

under very vigorous conditions, for example, when benzene or toluene is nitrated

to the trinitro derivative.

MacKie and Orton [71] found that tetranitromethane could be obtained by

reacting anhydrous nitric acid with acetylene in the presence of mercuric nitrate.

During World War II the Germans manufactured tetranitromethane by this method

on a semi-commercial scale, after they had developed the industrial process (Schim-

melschmidt [72]).

The reaction takes place in the presence of mercuric nitrate as a catalyst at

temperatures ranging from 45°C to 50°C (max. 60°C).

CH=CH + 2HNO 3 + (NO 2 ) 2 CH-CHO + H 2 O

(NO 2 ) 2 CH-CHO + HNO 3 -> (NO 2 ) 3 C-CHO + H 2 O

(NO 2 ) 3 C-CHO + 2HNO 3 -> (NO 2 ) 3 C-COOH + H 2 O + 2NO 2

(NO 2 ) 3 CH + CO 2

(NO 2 ) 3 CH + HNO 3 -> (NO 2 ) 4 C + H 2 O

The overall reaction may be presented as:

C 2 H 2 + 6HNO 3 -> (NO 2 ) 4 C + CO 2 + 4H 2 O + 2NO 2

in addition a side-reaction

C 2 H 2 + 10HNO 3 -> 2CO 2 + 6H 2 O + 10NO 2

also takes place.

1,2-DINITROETHANE

m. p. 39°C, b. p. 135°C

(24a)

(24b)

(24c)

(24d)

(25)

(26)

1,2-Dinitroethane may be obtained by the action of nitrogen dioxide on ethylene
at low temperature (about 0°C) (Semenoff [73]; Demyanov [74], [75]). According
to N. Levy, Scaife, Smith [76], the use of a mixture of ethylene with oxygen

in the volume ratio of about 4:1 gives good results.