MEDNA is an acronym for methylenediisonitrosoamine, it is also called N,N' dinitrosomethanedihydroxylamine. The information here is actually for the explosive salts of MEDNA as the free acid is unstable, there are several of importance. The sodium salt would seem to be of greatest importance with other salts being derived from it. The other salts include barium, cadmium, calcium, cesium, copper, monohydroxylamine, iron, lead, mercury, potassium, rubidium, silver, thallium, and tin. Of these, I have information for the barium, calcium, lead, potassium, silver, and sodium salts. All of these explosives are rather sensitive to shock, friction, and heat. They are usually used as detonators in mixtures with other common explosives. The sodium salt was first discovered around 1894.
|acetic acid||various beakers|
|barium chloride||graduated cylinder|
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The barium salt of MEDNA is precipitated by adding barium chloride to a solution of either sodium or potassium MEDNA. This compound has the least explosive power of all the salts.
The calcium salt of MEDNA is prepared by adding calcium chloride solution to a solution of sodium MEDNA, thus precipitating out the calcium MEDNA. I have no other information on its explosive properties.
The lead salt of MEDNA can be precipitated by adding a lead salt solution, such as lead acetate, lead chlorate, lead perchlorate, or lead nitrate, to a solution of sodium MEDNA. This explosive detonates at 250 °C. It can be mixed with lead picrate or lead styphnate for use in detonators.
Prepare a solution of 56.1 g of silver nitrate in 150 mL of water in a small beaker. Add this solution to a solution of 30 g of sodium MEDNA in 150 mL of water. The curdy silver salt is collected on a Buchner funnel, and washed on the filter paper with 450 mL of water. The damp salt is suspended in 200 mL of water, and the suspension is added slowly with stirring to a solution of 33.2 g of potassium iodide in 150 mL of water. The mixture is stirred for 3 hours, and allowed to stand for 16 hours more. A precipitate of silver iodide is filtered off, and the water is removed from the remaining solution in vacuum to give about 18.8 g of impure potassium MEDNA. This solid is dissolved in 50 mL of hot water, clarified with Celite, and cooled to 0 °C. A small amount of solid is filtered off, and the water is evaporated in vacuum to give 13.5 g of an almost white solid, this corresponds to approximatly 61% of the theoritical yield.
The silver salt of MEDNA is made as above by simply adding silver nitrate solution to the sodium salt of MEDNA without the potassium iodide.
Very slowly add 13.8 g of sodium metal in small portions to 300 mL of anhydrous ethyl alcohol and cool to 6 °C under nitrogen (If you have some sodium ethoxide handy that would do the trick since that is what this reaction makes, it is also safer). 38.4 g of acetone is added slowly with vigerous stirring as nitric oxide is passed in at 320 mL per minute for 140 minutes. A fine yellow solid should form and is collected on a Buchner funnel, then the damp solid is dissolved in 130 mL of water, made slightly acidic with glacial acetic acid, and heated on a steam bath until gassing ceases to come from the solution. The mixture is poured into 400 mL of ice cold ethyl alcohol to give 25.3 g of a brown solid which is recrystallized twice from a 2:1 ratio of ethyl alcohol and water to give a white solid which decomposes without melting at 225-260 °C.
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