Hantzsch and Rinckenberger obtained the ammonium salt of trinitromethane by treating tetranitromethane with aqueous ammonia.
It is well known that tetranitromethane can be reduced to nitroformate salts using an alkaline solution of hydrogen peroxide. This is the most usual
route for preparing trinitromethane. Prepare a solution of 168 g of potassium hydroxide in 350 mL of water in a round-bottomed 1000-mL Florence flask,
and cool to 5 °C with a salt-ice bath. While stirring, add 108 mL of 30% hydrogen peroxide to the solution. Next, add 117 mL of tetranitromethane at
a rate which keeps the temperature at 20-25 °C, add while stirring. The temperature is then allowed to rise to 30 °C over 15 minutes. The bright
yellow solid, that should have formed, is filtered to collect it using glass filter paper because of its high acidity, washed with anhydrous methyl
alcohol, then anhydrous ethyl ether, and finally air dried to give 100% of the potassium salt of trinitromethane. The salt is suspended in anhydrous
ethyl ether and anhydrous hydrogen chloride gas is passed in until the yellow color disappears. The white precipitate of potassium chloride is
filtered off and washed with anhydrous ethyl ether. The ethyl ether is evaporated from the filtrate and additional washings at reduced pressure give
85-90% of crude trinitromethane which can be purified by sublimation.
Although usually an oxidizer, in some reactions hydrogen peroxide can act as a reducing agent. For example, it reacts with hypochlorite to form
chloride and oxygen gas. Similarly, an alkaline solution of H2O2 reduces Cl2 to Cl- ions. |
, however, in the preceding paragraph they reference:
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represent the delocalised 3 électrons all over the planar molecular structure just as if it was aromatic.