METHOD FOR SYNTHESIZING 1,1-DIAMINO-2,2-DINITROETHYLENE (FOX-7) OR A SALT THEREOF

Abstract

In a method for synthesizing 1,1-diamino-2,2-dinitroethylene (FOX-7) or an N-substituted diamino derivative thereof or a salt of 1,1-diamino-2,2-dinitroethylene or of the N-substituted diamino derivative, a carbodiimide is reacted with a dinitromethane anion. The reaction of the carbodiimide with the dinitromethane anion takes place in a solution.

Claims

1. A method for synthesizing 1,1-diamino-2,2-dinitroethylene (FOX-7) or an N-substituted diamino derivative thereof or a salt of the 1,1-diamino-2,2-dinitroethylene or of the N-substituted diamino derivative, which comprises the step of: reacting a carbodiimide with a dinitromethane anion.

2. The method according to claim 1, which further comprises forming the carbodiimide as C(NH).sub.2.

3. The method according to claim 1, which further comprises performing the reacting of the carbodiimide with the dinitromethane anion in a polar aprotic solvent.

4. The method according to claim 3, which further comprises providing dimethylformamide (DMF) as the polar aprotic solvent.

5. The method according to claim 3, which further comprises adding a protic solvent to the polar aprotic solvent.

6. The method according to claim 5, which further comprises selecting the protic solvent from the group consisting of water and alcohol.

7. The method according to claim 3, which further comprises performing the reacting step at a pH in a range of 6.5 to 7.5.

8. The method according to claim 3, wherein the dinitromethane anion is associated with a potassium ion or an ammonium ion as a counterion.

9. The method according to claim 1, which further comprises converting a 1,1-diamino-2,2-dinitroethylene anion formed in the synthesis into the 1,1-diamino-2,2-dinitroethylene by lowering a pH of a solution containing the 1,1-diamino-2,2-dinitroethylene anion.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

[0016] FIG. 1 shows a reaction scheme of a synthesis of FOX-7 from nitration of a nitrogen heterocycle with subsequent hydrolysis to an end product;

[0017] FIG. 2 shows a reaction scheme of a synthesis of FOX-7 from nitration of 2-methyl-2-methoxyimidazoledione;

[0018] FIG. 3 shows a reaction scheme of a synthesis of FOX-7 from nitration of 2-methyl-4,6-pyrimidinedione; and

[0019] FIG. 4 shows a reaction scheme of the synthesis of KFOX-7 from carbodiimide.

DETAILED DESCRIPTION OF THE INVENTION

[0020] To carry out the reaction shown in FIG. 4, 778 mg (5.4 mmol) of potassium dinitromethanate are dissolved in 20 ml of DMF at 60° C. in a 50 ml beaker and 226 mg (5.4 mmol) of carbodiimide in the form of C(NH).sub.2 are added. The solution is stirred at 60° C. for 2 hours and then allowed to cool to room temperature with stirring. After distilling off the solvent, the residue is dried in an explosion-proof drying oven at 50° C. and then measured thermoanalytically by dynamic differential scanning calorimetry (DSC) and also by IR, NMR and mass spectroscopy. The results are shown in Table 1 below.

TABLE-US-00001 TABLE 1 Analysis Reaction product KFOX-7 reference 1H-NMR (400 8.54 ppm (s) 8.8 ppm (s) (FOX-7) MHz) 13C-NMR (400 158.4 ppm (s) 158.41 ppm (s) (KFOX-7) MHz) Mass spectrum 148.3 m/z 148.1 m/z (FOX-7) DSC 230° C. 228° C. (KFOX-7)

[0021] Comparison with the KFOX-7 reference shows that the reaction product comprises the 1,1-diamino-2,2-dinitroethylene anion.

[0022] In the working example, it is also possible to use ammonium dinitromethanate in place of potassium dinitromethanate and/or also another carbodiimide in place of C(NH).sub.2.