US3432524A - Nitro-substituted dioxolanes and their method of preparation - Google Patents

Description

United States Patent 3,432,524 NITRO-SUBSTITUTED DIOXOLANES AND THEIR METHOD OF PREPARATION Gustave B. Linden, Short Hills, N.J., assignor to Aerojet- Glelneral Corporation, Azusa, Calif., a corporation of 0 io No Drawing. Original application Nov. 26, 1963, Ser. No. 326,288, now Patent No. 3,306,929, dated Feb. 27, 1967. Divided and this application Nov. 4, 1966, Ser. No. 632,835

US. Cl. 260-3403 3 Claims Int. Cl. 'C07d 13/04 ABSTRACT OF THE DISCLOSURE This patent describes novel compounds of the formula wherein R is hydrocarbyl and R is hydrogen, lower alkyl, lower aryl, lower alkaryl or lower aralkyl; and their method of preparation by reacting a diol of the formula with a carbonyl compound of the formula 0 H R'GR in the presence of an acid esterification catalyst. These compounds contain a plurality of nitro groups and are inherently useful as high explosives.

wherein R is hydrocarbyl, preferably lower alkyl having Patented Mar. 11, 1969 The compounds of Formula I are prepared in accordance with the following general reaction equation:

wherein R and R are as defined above.

According to Reaction II, it can be seen that the 5,5,5- trinitro-1,2-pentanediol is reacted with an aldehyde or ketone to form a substituted -4(3',3',3'-trinitropropyl-1,3- dioxolane.

Illustrative compounds which are obtained by the practice of Reaction II together with the corresponding rea ant materials are set forth in the following table.

The above reaction may optionally be carried out in any inert solvent, i.e., polar solvents such as water, methanol, ethanol, etc.; and non-polar solvents, i.e., benzene, hexane, toluene, etc. The proportions of the reactants employed in the reaction are not critical. Normally, stoichiometrically equivalent amounts are used since this results in the most economical utilization of the reactants. Thus, usually one mole of alcohol is used per mole of ketone or aldehyde. The reaction temperature should normally be sufliciently high so that the reactants will dissolve to a substantial degree in the reaction medium, but in any event, the reaction temperature should be below the compositon temperature of the reactant. Normally, the reaction is conducted at a temperature between about 0 C. and about 100 C. The most preferred temperature is from about +20 C. to about C. Pressure is not critical in this reaction. Therefore, while any pressure can be used, the reaction is. normally run under atmospheric pressure.

The above reaction is preferably conducted in the presence of an effective catalytic amount of an acid esterification catalyst such as cupric sulfate or boron trifiuoride etherate.

3 EXAMPLE 1 Preparation of the 2,2-dimethyl-4(3',3',3'-trinitropropyl)- 1,3-dioxolane The 5,5,5-trinitro-1,2-pentanediol (427 grams) was dissolved in 1500 ml. acetone. This solution was stirred with 600 g. anhydrous powdered cupric sulfate and 3 ml. boron trifluoride etherate for 20 hours. The copper sulfate was removed by filtration and the acetone was removed under reduced pressure. The residual oil was transferred to a beaker and 600 ml. ice water was added with stirring. The oil crystallized instantly. The product was filtered, washed thoroughly with ice water, and dried in vacuo. The yield of moist product wasc 405 g., M.P. 34 to 35 C. This crude dioxolane was heated to boiling with 1300 ml. hexane on the steam bath and the nearly colorless, cloudy solution was decanted from a small layer of oil and water. The hexane solution was clarified by shaking with 50 g. sodium sulfate and filtering. The hexane solution was cooled and seeded and left in a deep-freeze overnight. The colorless product was collected by filtration and dried in vacuo. The yield of 2,2 dimethyl-4(3,3,3'-trinitropropyl)-l,3-dioxolane was 3.6 g., M.P. 38 to 39 C.

When the foregoing example is twice repeated using first acetaldehyde and then benzophenone in lieu of acetone, good yields of 2-methyl-4(3',3',3'-trinitropropyl)- 1,3-dioxolane and 2,2-diphenyl-4(3',3,3'-trinitropropyl)- 1,3-dioxolane, respectively, are obtained.

The compounds of Formula I may be isolated in conventional manner by filtration, evaporation, extraction and/ or distillation.

The compounds of Formula I, which contain a plurality of nitro groups, are inherently useful as high explosives. These compounds can also be used in any conventional explosive missile, projectile, rocket or the like, as the main explosive charge. An example of such a missile is described in US. Patent 2,470,162, issued May 17, 1949. One way of using such high explosives in a device such as that disclosed in US. Patent 2,470,162 is to absorb the liquid explosive in an absorbent material such as cellulose, wood pulp, or sawdust. The resultant dynamitetype explosive can then be packed into the warhead of the missile. A charge thus prepared is sufficiently insensitive to withstand the shock entailed in the ejection of a shell from a gun barrel or a rocket launching tube under the pressure developed from ignition of a propellant charge, and can be caused to explode on operation of an impact or time-fuse mechanism firing a detonating explosive such as lead azide or mercury fulminate.

The acetals of this invention are also useful as fungicides.

This example describes a particular method of preparing a novel propellant composition according to this invention from the following ingredients wherein 2,2-dimethyl 4(3',3',3'-trinitropropyl)-1,3-dioxolane is one of the plasticizers.

EXAMPLE II The aluminum powder is stirred into about /3 of the required volume of polypropylene glycol and glycerol monoricinoleate. The mixture is prepared in a stainless steel container, using a copper-beryllium spatula. Mixing is continued for about ten minutes.

The aluminum slurry is added to a conventional mixer equipped with facilities for heating, cooling, and vacuumizing the propellant mix. The walls of the aluminum slurry container are scraped thoroughly. The container is rinsed with /2 of the required volume of dioctyl azelate and the rinses are added to the mixer. The remaining polypropylene glycol is added to the mixer. The 2,2-dimethyl- 4(3,3',3-trinitropropyl)-l,3-dioxolane is mixed with the remaining dioctyl azelate until homogeneous and the solution is then added to the mixer.

With the mixer off, the ferric acetylacetonate, phenyl benanaphthylamine, and lecithin are added through a 40- mesh screen. The copper chromite is added to the mixer.

The mixer is covered and mixed by remote control for 15 minutes under 26 to 28 inches of vacuum, after which it is stopped and the vacuum released with dry nitrogen. The cover is removed from the mixer and the oxidizer is added by remote control with the mixer blades in motion.

After all of the oxidizer has been added, the mixer is stopped and scraped down. The propellant mass is mixed for 15 minutes at 7 0 F. and 2 6 inches vacuum by remote control. The mixer is stopped and the vacuum released with dry nitrogen. The tolylene diisocyanate is added, after which the mass is mixed for ten minutes at 70 F. and 26 inches of vacuum by remote control. The vacuum is released with dry nitrogen and the mixture is cast.

It will be understood that various modifications may be made in this invention without departing from the spirit thereof.

I claim:

1. A compound having the formula:

NO: /OC H-CHr-CHr-Af-NO:

wherein R is lower alkyl and aryl of 6 to 12 carbon atoms, and R is selected from the group consisting of hydrogen, lower alkyl and aryl of 6 to 12 carbon atoms.

2. A compound having the formula:

Boekelheide et al., Journal of American Chemical Society, vol. 71 (1949), pp. 3304-3307.

ALEX MAZEL, Primary Examiner.

JAMES H. TURNIPSEED, Assistant Examiner.

US. Cl. X.R. 149038; 260999