CS218703B1 - Method of making the 1,3,5,7-tetranitro-1,3,5,7-octanetetraazacycles - Google Patents

Abstract

The invention relates to the production of 1,3,5,7-tetranitro- -1,3,5,7-tetraazacyclooctane by nitrolysis of 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane acid nitric oxide containing nitric oxide; the reaction conditions are adjusted by addition ammonium nitrate, resulting in an increase yield and process safety. The invention can be advantageously used in manufacturing of the title substance starting from 1,5-diacetyl- -3,7-dinitro-1,3,5,7-tetraazacyclooctane

Description

The present invention relates to the preparation of 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane by nitrolysis of 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane with nitric acid containing nitric oxide wherein the reaction conditions are adjusted by the addition of ammonium nitrate, resulting in increased process yield and process safety.

The invention can be advantageously utilized in the preparation of the title substance starting from 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacycloctocane.

The present invention relates to the preparation of 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane by nitrolysis of 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane with nitric acid containing nitric oxide; wherein the reaction conditions are chosen such that they favorably influence the economics of the process.

A common process for the preparation of 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane, also called octogen, also referred to as the HMX code, consists in nitrolysis of hexamethylenetetramine and / or 1,5-endomethylene-3,7-dipitro -l, 3,5,7-tetraazacyclococtane (bibliography by E. Ju. Orlova: Oktogen - termostojkoe vzryvčatoe vščestvo, Izdat. Nedra, Moscow, 1978). However, over the past decade, attention has increasingly been drawn to the processes by which octogen is obtained through 1,5-dialkanoyl-3,7-endomethylene-1,3,5,7-tetraazacycloctocanes; their preparation is described e.g. in V.I. Siele, M. Warman and E.E. Gilbert: J. Heterocycl. Chem. 197,411.237; US Pat. 3,850,923 and 3,849,414.

A method of octogen synthesis starting from 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane as an intermediate (U.S. Pat. No. 3,939,148) appears to be a very attractive production method. This intermediate results from hexamethylenetetramine in yields of 91-98% over theory (U.S. Pat. Nos. 3,850,923 and 3,926,953); its codename is DADN. Nitrolysis of 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane with nitric acid containing up to 50 wt. nitric oxide, depending on the reaction conditions and, to a lesser extent, the nitric oxide source, provides octogen at 41-98% of theory (U.S. Pat. No. 3,939,148). A disadvantage of this known process of nitrolose 1,5-di-ethyl-3,7-dinitro-1,3,5,7-tetraazacycloctocane is that fresh distilled anhydrous nitric acid must be applied in large excess over theory to ensure high octogen yield. U.S. Pat. No. 3,939,148). So eg. to obtain 1 wt. 34.5% by weight of octogen of 100% purity and in a yield of 98% of theory. % by weight of freshly distilled anhydrous nitric acid; % of phosphorus pentoxide. The major side reaction of the nitrolysis of 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane is the cleavage of the 1,3,5-tetraazacyclooctane skeleton. In addition to the reaction conditions in the general sense, the course of this undesired reaction is also dependent on the kind of nitric oxide source (a combination of nitric acid and phosphorus pentoxide or sulfur trioxide or trifluoroacetic anhydride or a solution of nitric oxide in nitric acid or nitromethane, U.S. Pat. ).

The undesirable extinction of the 1,3,5,7-tetraaazacyclooctane skeleton can be suppressed by the addition of a component capable of exiting the product-side acidolytic equilibria and exhibiting a higher affinity for nitrogen oxides than the nitrolyzed substance.

According to the present invention, a process for the preparation of 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane by nitration of 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane with nitric acid containing nitric oxide is carried out in such a way that the nitrolysis process takes place in the presence of ammonium nitrate to the reaction system added in an amount of 0.05 to 20.0% by weight, preferably 5 to 15% by weight, calculated on the weight of the reaction taken 1.5 -di4cetyl-3,7-diriitrp-l, 3,5,7-tetraazacyklooktánu.

An advantage of the process of the present invention is that freshly distilled and anhydrous nitric acid is not required, allowing the yield of high purity octogen of about 89% compared to the theory to be achieved with a reduced amount of nitration mixture.

In addition to this economic effect, the advantage of the present invention is the potential for increased process safety since ammonium nitrate enhances the stability of nitrolysis mixtures (U.S. Pat. No. 97,100; V. Kadeřábek and J. Denkstein: Coll. Czech. Chem. Commun. 1960, 25, 1070 ; Czechoslovak author's certificate ...... = PV 7398-79).

The novel and higher effect achieved for the purposes of the present invention has not been described in the literature so far and is illustrated by the following examples.

Example 1

210 obj. parts by weight of nitric acid 97.15% with a content below 0.2% by weight. of analytical nitric acid (i.e. 307 parts by weight of nitric acid as anhydrous) was cooled to -10 ° C with stirring. 120 wt. parts of phosphorus pentoxide such that the temperature of the resulting mixture does not exceed 40 ° C. Thereafter, 30 wt. parts of 1,5-di-diethyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane and the temperature of the mixture is adjusted to 58-62 ° C over a period of 4 to 7 minutes, at which temperature the reaction mixture is maintained for for 20 minutes. After this time, without cooling, the reaction mixture was poured into 500 vol. The resulting suspension is brought to boiling and held there until the evolution of nitrogen oxides stops. After the suspension has cooled to 18-25 ° C, the octogen is isolated by filtration, washed on the filter with water until the filtrate is neutral, and dried at 90-95 ° C. For the dry product, the melting point is determined. This basic process is repeated several times, with some ammonium nitrate being introduced together with 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane; The results are presented in Table 1 below:

Table 1 '.218703

Amount of ammonium nitrate Yield HMX M.p. wt. parts wt. % per DADN wt. parts % versus theory 0.00 0.00 22,00 71.86 282.0 to 283) 0 0.02 0.10 22.05 72,01 282.0 to 283.0 0.50 1.66 22.81 74.50 282.0 to 283.0 1.00 3.33 23.50 76,80 282.5 to 283.0 2.00 6.66 24.59 80.36 282.5 to 283.0 3.00 10.00 25.00 approx. 81.67 283.5 to 285.0 6.00 20.00 21.22 approx. 69.25 ^h 285.0 to 285.5

Note: ¹ by thin-layer chromatography (Silufol UV 254) in the acetone-cyclohexane system showed the starting material 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane.

Depending on the recovery rate on the amount of ammonium nitrate introduced into the reaction system, it is evident that the highest recovery rate, i.e.. j. 81.7% over crude octogen theory is achieved by the addition of 10.5 wt. ammonium nitrate to the charge of 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacycloctane. Under the given reaction conditions, additions above 10 wt. For the assessment of raw material consumption in this example, the recovery of 81% of octogen compared to the theory, achieved by the addition of 7.8% by weight, is assumed for the DADN feedstock to give an O.D. content of the starting substance (estimated below 5% by weight). ammonium nitrate, calculated on DADN weight: under the above conditions, 1 wt. parts of pure octogen need 12.71 wt.

% by weight of a 97.15% nitric acid (i.e., 12.35 wt.% anhydrous nitric acid); % of phosphorus pentoxide and 0.094 wt. works of ammonium nitrate.

Example 2

The procedure is as in Example 1, except that a portion of 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane is used in an amount of 20% by weight. and the reaction time in the temperature range 53-58 ° C is 30 minutes. Ammonium nitrate is introduced into the nitration mixture prior to the actual dosing of 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacycloctocane.

The results are presented in Table 2 below.

Table 2

Amount of ammonium nitrate Yield HMX Melting point HMX in ° C wt. parts wt. % per DADN wt. parts % versus theory 0.00 0.00 17,00 83.30 280.0 to 283.0 0.25 1.25 17.25 84.52 282.0 to 283.0 0.50 2.50 17.50 85.75 282.5 to 238.0 1.00 5.00 18.01 88.20 282.5 to 283.0 1.50 7.50 18,30 89.67 283.0 to 283.5 2.00 10.00 17.95 about 87.95 ^to 284.0 to 284.5 3.40 17,00 16.50 approx. 80.85 ⁺ 284.0 to 285.0

Note: starting from 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane (DADN) and traces of 1-acetyl, thin-layer chromatography (Silufol UV 254) in acetone-cyclohexane system -3,5,7-trinitro-1,3,5,7-tetraazacyclooctane (SEX) in total amount below 5 wt.

Raw material consumption for maximum yield, t. j. for 89.67% octogen versus theory, per 1 wt. % pure octogen is 17.23 wt. parts by weight of nitric acid 97.15% (i.e. 16.74 parts by weight of nitric acid as anhydrous); parts of phosphorus pentoxide and 0.082 wt. parts of ammonium nitrate.

Depending on the yield on the amount of ammonium nitrate in the reaction system, it is apparent that the yield without the addition of ammonium nitrate is equivalent to that with an addition of 15% by weight. ammonium nitrate, calculated on the starting 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane.

Claims (1)

SUBJECT Process for the preparation of 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane by nitration of 1,5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane with nitric acid containing nitric oxide characterized in that the nitrolysis process is carried out OF THE INVENTION in the presence of ammonium nitrate to the reaction system added in an amount of 0.05 to 20.0% by weight, preferably 5 to 15% by weight, calculated on the weight of the reaction taken of 1,5-diacetyl-3,7-dinitro- 1,3,5,7-Tetraazacyclooctane.