High Powered New Explosive Developed

[tranquillity]

A research team led by David E. Chavez at Los Alamos National Laboratory (USA) has now developed a novel tetranitrate ester.

http://www.sciencedaily.com/releases/2008/10/081010102718.htm

The new compound contains 6 carbons, 4 nitro-ester groups and 2 nitro groups. A picture of the molecule can be seen at the link above.

It has sensitivity similar to PETN. The explosive melts at 85C and decomposes at 141C which makes it a perfect candidate for melt casting either on its own or with other explosives. It also apparently has the highest density of any nitrate ester and power that could rival HMX.

[Alexires]

The referenced article (with synthesis).

[fluoroantimonic]

Very interesting. The synthesis starting from the dioxane looks doable. As long as the dioxane isn't too hard to synthesize, it looks like it wouldn't be too hard at all. Very nice find.

[tranquillity]

Working from the synthesis presented by nbk2000
http://www.roguesci.org/theforum/showthread.php?t=5299

50g tris(hydroxymethyl)nitromethane is prepared by reacting 20g of nitromethane and 75g 40% formaldehyde in the presence of KHCO3.

Now for the theoretical part: tris(hydroxymethyl)nitromethane is separated and purified then dissolved in toluene and p-toluenesolphonic acid. 1 molar equivalent of acetone is added and it is refluxed with the addition of something to remove the water.

See http://www.organic-chemistry.org/protectivegroups/carbonyl/dioxanes-dioxolanes.htm

Someone with more than 1st year organic chemistry will probably come up with something better.
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The synthesis can then proceed as is stated in the PDF. When compound 4 is reached I suppose it may be nitrated with H2SO4/XNO3 hopefully shouldn’t affect the existing nitro groups.

An alternative to methanol in the steps converting compound 3 to compound 4 on the pdf would probably be dry ethanol or methylated spirits.

[tranquillity]

EXAMPLE 1

A 100 ml round bottom flask equipped with a stir bar and reflux condenser topped with a nitrogen inlet was charged with 15.1 g (0.1 mol) of tris(hydroxymethyl) nitromethane and 22 ml (0.3 mol) of acetone. The mixture was heated until all the tris(hydroxymethyl)nitromethane had dissolved and then was cooled to 15°-20° C. The trimethylol compound crystallized in fine needles. Boron trifluorideetherate (13 ml, 0.1 mol) was added with stirring. The temperature rose to 55° C. and crystals of product began to separate. After five minutes, the mixture was poured into a stirred mixture of 110 ml of saturated sodium bicarbonate solution and excess ice. After stirring for 15 minutes, the product, 2,2-dimethyl-5-hydroxymethyl-5-nitro-1,3-dioxane was collected by filtration, washed with cold water and dried in vacuo. The yield was determined to 88%.

Source http://www.freepatentsonline.com/4851588.html

Hopefully the Boron trifluorideetherate could be substituted with a different acid.

Or

Example 10 :

Following the procedure 2(B) described in this application; to a 25 ml round bottom flask equipped with a stir bar was added 1g (0.007 mol) tris(hydroxymethyl) nitormethane, 8 ml (0.07 mol) 2,2-diemthoxypropane and 2 drops concentrated hydrochloric acid. The reaction was heated to 45-50°C for 30 minutes. After cooling to room temperature the volatiles were removed in vacuo to give a white solid 2,2-dimethyl-5-hydroxy methyl-5-nitro-1,3-dioxane in 93% yield.

Source http://www.freepatentsonline.com/EP0348223.html

2,2-Dimethoxypropane could probably be produced from a reaction mixture containing methanol, acetone and H2SO4 to remove the water and force the equilibrium forward.

[fluoroantimonic]

That is some very good news!

The production of the dimethoxypropane looks pretty easy. For example:

670 g (11.5 moles) of acetone, 740 g (23 moles) of methanol and 40 g (about 1 mole) of hydrogen chloride were stirred for one hour at room temperature with a suspension of 5.5 kg of decane and 4.1 kg (about 30 moles) of anhydrous calcium sulfate. Working up the liquid phase by distillation gave 150 g of an azeotrope of 8 g of 2,2-dimethoxypropane, 30 g of acetone and 112 g of methanol, 177 g of an azeotrope of 83 g of the ketal and 94 g of methanol, and 910 g of 2,2-dimethoxypropane of 99% purity. US Patent 4136124
I would bet MgSO4 would work well too, and you'd need a lot less of it since it absorbs a lot more water per gram. Also suspending it in decane wouldn't be needed for small scale preparation, simply suspending it in the reaction mix and filtering later would probably be easier.

The production of something that powerful from such simple things as nitromethane, formaldehyde, methanol, acetone, NaOH, NaCl, H2O2, H2SO4 and XNO3 is pretty damn amazing in my opinion. Everything looks workable, almost every precourser looks relatively easy to prepare.

The Ac2O required for the nitration is unfortunate, but I don't think it would be prohibitive. Synthesis via toluene -> benzotrichloride -> benzoyl chloride -> acetyl chloride -> Ac2O shouldn't be too hard. And maybe you could get away without using it anyway.