CN114634462A

CN114634462A - Nitro-imitation energetic compound containing furoxan ring or available salt thereof and preparation method thereof

Info

Publication number: CN114634462A
Application number: CN202210401201.7A
Authority: CN
Inventors: 何春林; 陈鹏; 庞思平; 窦辉
Original assignee: Beijing Institute of Technology BIT
Current assignee: Beijing Institute of Technology BIT
Priority date: 2022-04-15
Filing date: 2022-04-15
Publication date: 2022-06-17
Anticipated expiration: 2042-04-15
Also published as: CN114634462B

Abstract

The invention discloses an oxazazan ring-containing nitrating energetic compound or an available salt thereof, wherein an oxadiazole ring and an azo group are introduced into an oxazan heterocyclic ring, the density of coordinated oxygen on the oxazan ring can be effectively improved, and the nitrogen content and the enthalpy of formation can be effectively improved by the azo group, so that the oxazan ring-containing nitrating energetic compound has more advantages in the application of energetic materials. The invention starts from the known available raw materials, synthesizes the nitrone compound containing the furoxan ring neutrality and the salt containing the furoxan ring energy through multi-step reaction work, the detonation performance of the synthesized nitrone compound has obvious advantages in the currently known neutral nitrone compound, and the compound has great potential to be used as a propellant oxidizer.

Description

Nitro-imitation energetic compound containing furoxan ring or available salt thereof and preparation method thereof

Technical Field

The invention relates to the technical field of energetic materials, in particular to an oxidized furazan ring-containing nitramine energetic compound or an available salt thereof and a preparation method thereof.

Background

With the continuous expansion of the types of energetic materials and the continuous improvement of the requirements of weapons and equipment on the performance of the energetic materials, the high-energy density materials have the characteristics of high energy, high density, high thermal stability, insensitivity to external stimulation and the like, so that the high-energy density materials become hot explosive materials, and high-energy low-sense energetic compounds serving as the core of the high-energy density materials become hot spots for the research of the energetic materials in recent years.

In the research of high-energy energetic materials, energetic compounds with high detonation performance capable of serving as propellant oxidants are also the direction of efforts of researchers.

Disclosure of Invention

An object of the present invention is to solve at least the above problems and/or disadvantages and to provide at least the advantages described hereinafter.

It is still another object of the present invention to provide an oxidized furazan ring-containing nitrated energetic compound or a usable salt thereof, which effectively increases the density of the energetic compound by introducing oxadiazole rings of different structures into an oxidized furazan qiaoqiao ring, so that the application of the energetic compound is more advantageous.

It is yet another object of the present invention to provide a process for the preparation of furazan ring-containing nitroxide-containing compounds or useful salts thereof which, starting from the known available starting materials, synthesize neutral nitroxide-containing compounds as well as furazan ring-containing salts by a multi-step reaction function, the synthesized nitroxide-containing compounds possess the highest detonation performance among the currently known neutral nitroxide-containing compounds and have great potential for use as propellant oxidizers.

To achieve these objects and other advantages in accordance with the present invention, there is provided an oxidized furazan ring-containing nitramine energetic compound or a useful salt thereof, wherein the energetic salt has the structure of formula (I):

wherein R is₁Is a nitrogen-containing straight chain group; r₂Containing an oxadiazole ring radical, R₃Is an oxadiazole ring-containing group.

Preferably, wherein when R is₂And R₃Is composed of

The energetic compound is in an unsalified structure.

Preferably, wherein R is₁is-NH-or-N ═ N-.

Preferably, wherein R2 and R₃Is composed of

The energy-containing compound is in a salt forming structure, and the salt forming structure is ammonium salt, hydroxylamine salt or hydrazine salt.

The object of the invention can be further achieved by a method for preparing a nitromimic energetic compound containing an oxidized furazan ring or a usable salt thereof, comprising the steps of:

step one, synthesis of intermediate compound of formula (III)

The compound of the formula (III) is obtained by taking the available compound of the formula (II) as a raw material through multi-step reaction;

step two, synthesis of compound of formula (I)

Reacting the compound of the formula (III) obtained in the step one with a basic compound, or further reacting a product obtained after the reaction with the basic compound to obtain a compound of the formula (I);

preferably, among the compounds of formula (III), R₄is-N ═ N-.

Preferably, in the second step, the basic compound is ammonia water or hydrazine hydrate.

Preferably, wherein, in the second step, the molar ratio of the compound of formula (III) to the basic compound is 1: 10.

The invention at least comprises the following beneficial effects:

1. according to the invention, oxadiazole rings with different structures are introduced into the furoxan heterocyclic ring, and the coordinated oxygen on the furoxan ring can effectively improve the density of an energy-containing compound, so that the furoxan heterocyclic ring has more advantages in application of energy-containing materials.

2. According to the preparation method of the nitrone compound containing the furazan oxide ring or the available salt thereof, the nitrone compound and the nitrone salt containing the furazan oxide ring are synthesized by starting from the known available raw materials through multi-step reaction functions, the detonation performance of the synthesized neutral nitrone compound has obvious advantages in the currently known neutral nitrone compound, and the compound has great potential of being used as a propellant oxidant.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.

Drawings

FIG. 1 is a single crystal structural view of Compound 3 in example 1 of the present invention;

FIG. 2 is a nuclear magnetic resonance hydrogen spectrum of Compound 3 in example 1 of the present invention;

FIG. 3 is a NMR spectrum of Compound 3 in example 1 of the present invention;

FIG. 4 is a single crystal structural view of Compound 5 in example 1 of the present invention;

FIG. 5 is a DSC of compound 5 in example 1 of the present invention;

FIG. 6 is a NMR spectrum of Compound 5 in example 1 of the present invention;

FIG. 7 is a NMR spectrum of Compound 5 in example 1 of the present invention;

FIG. 8 is a single crystal structural view of Compound 6 in example 1 of the present invention;

FIG. 9 is a DSC of compound 6 in example 1 of the present invention;

FIG. 10 is a NMR spectrum of Compound 6 in example 1 of the present invention;

FIG. 11 is a NMR spectrum of Compound 6 in example 1 of the present invention;

FIG. 12 is a DSC of compound 7 in example 2 of the present invention;

FIG. 13 is a NMR chart of Compound 7 in example 2 of the present invention

FIG. 14 is a NMR carbon spectrum of Compound 7 of example 2 of the present invention;

FIG. 15 is a DSC of compound 8 of example 3 of the present invention;

FIG. 16 is a NMR spectrum of Compound 8 of example 3 of the present invention;

FIG. 17 is a NMR carbon spectrum of Compound 8 of example 3 of the present invention;

FIG. 18 is a single crystal structural view of Compound 9 in example 4 of the present invention;

FIG. 19 is a DSC of compound 9 in example 4 of the present invention;

FIG. 20 is a NMR carbon spectrum of Compound 9 of example 4 of the present invention;

FIG. 21 is a NMR carbon spectrum of Compound 9 of example 4 of the present invention.

Detailed Description

The present invention is further described in detail below with reference to the attached drawings so that those skilled in the art can implement the invention by referring to the description text.

It will be understood that terms such as "having," "including," and "comprising," as used herein, do not preclude the presence or addition of one or more other elements or groups thereof.

It is to be noted that the experimental methods described in the following embodiments are all conventional methods unless otherwise specified, and the reagents and materials are commercially available unless otherwise specified.

< example 1 >

The furazan ring-containing energetic salt 6 has a structural formula as follows:

the specific synthetic route is as follows:

the specific synthesis steps are as follows:

step one, synthesis of compound 3

Compound 1(1g, 6.3mmol) was dissolved in 20mL of acetonitrile and malonic acid methyl ester was added in one portionAcid chloride (0.86g, 6.4mmol), the solution became clear and cloudy after 2min, after 3h of reaction the precipitate was filtered and the solvent was removed by rotary evaporation, washed with water and dried under vacuum at 70 ℃ to give white compound 2(1.47g, 90.24%). Compound 2(1g, 3.86mmol) was dissolved in 15mL of acetonitrile at room temperature, and Cs was added₂CO₃(1.26g, 3.86mmol) and stirring for 1h, the solution gradually produced a yellow precipitate, after the reaction was complete the suspension was rotary evaporated to remove the solvent, washed with water and dried under vacuum to give compound 3 as a pale yellow compound (0.48g, 51.6%). The single crystal structure of the compound 3 is shown in figure 1, the nuclear magnetic resonance hydrogen spectrum is shown in figure 2, and the nuclear magnetic resonance carbon spectrum is shown in figure 3.

Step two, synthesis of Compound 5

In a three-necked flask, compound 3(1g, 4.15mmol) and CHCl were charged₃(10mL), concentrated HCl (10mL) was added to the system, compound 3 was dissolved in concentrated HCl, and then the prepared KMnO was added dropwise to the system₄(0.76g, 4.8mmol) of 15mL of aqueous solution, controlling the temperature to be not higher than 30 ℃, reacting for 5 hours at normal temperature to ensure that the reaction system is red, and dropwise adding 5% H₂O₂Removing excess KMnO₄After separation, the solvent was removed by rotary evaporation to give a viscous red solid, compound 4(0.9g, 90.75%). To compound 10(0.9g, 1.88mmol) was added dropwise concentrated H in an ice bath at-5 deg.C₂SO₄(5mL) was dissolved sufficiently, and 2.5mL of fuming nitric acid was added from a dropping funnel; reaction at-5 ℃ for 30min, then slowly warming overnight, a yellow precipitate appeared in the system, which was filtered and washed with 3 × 10mL trifluoroacetic acid to give yellow compound 5(0.76g, 61.34%) after drying.

The structure of the single crystal of compound 5 is shown in FIG. 4, the DSC diagram of compound 5 is shown in FIG. 5, the NMR spectrum is shown in FIG. 6, and the NMR spectrum is shown in FIG. 7.

Step three, synthesis of compound 6

Adding compound 5(0.66g, 1mmol) into 8mL of water to form a suspension, stirring at normal temperature, dropwise adding 0.68g (10mmol) of ammonia water, reacting at normal temperature for 6h, gradually changing yellow precipitate in the reaction system into dark brown precipitate, filtering, collecting brown precipitate, and drying at 50 ℃ under vacuum to obtain orange compound 6(0.46g) with a yield of 79.5%.

The structure of the single crystal of compound 6 is shown in FIG. 8, the DSC diagram is shown in FIG. 9, the NMR spectrum is shown in FIG. 10, and the NMR spectrum is shown in FIG. 11.

< example 2 >

The furazan ring-containing energetic salt 7 has a structural formula as follows:

the specific synthetic route is as follows:

the specific synthesis steps are as follows:

compound 6(0.58g, 1mmol) was suspended in 15mL of water at 0 ℃ and 50% H was added dropwise₂SO₄(3mL), after 10min of reaction was extracted with 3X10mL of ether, the organic phases were combined and dried over anhydrous sodium sulfate, filtered, 50% aqueous hydroxylamine solution (0.15g, 2.2mmol) was added dropwise to the reaction solution, and after 20min the precipitate was collected by filtration and dried under vacuum to give compound 7 as an orange color (0.46g, 75.4%).

The DSC chart of the compound 7 is shown in figure 12, the nuclear magnetic resonance hydrogen spectrum chart is shown in figure 13, and the nuclear magnetic resonance carbon spectrum chart is shown in figure 14.

< example 3 >

The furazan ring-containing energetic salt 8 has a structural formula as follows:

the specific synthetic route is as follows:

the specific synthesis steps are as follows:

at room temperature, compound 5(0.66g, 1mmol) was added portionwise to 8mL acetonitrile to dissolve a dark red solution, 0.5g (10mmol) hydrazine hydrate in acetonitrile (5mL) was added dropwise to the reaction solution, the reaction solution was stirred overnight, the precipitate was collected by filtration and dried under vacuum to give the hydrazonium salt 8(0.42g, 68.8%) as an orange solid.

The DSC chart of the compound 8 is shown in figure 15, the nuclear magnetic resonance hydrogen spectrum chart is shown in figure 16, and the nuclear magnetic resonance carbon spectrum chart is shown in figure 17.

< example 4 >

A nitragin compound 9 having the formula:

the specific synthetic route is as follows:

the specific synthesis steps are as follows:

compound 6(576mg, 1mmol) was dissolved in concentrated H₂SO₄(3.0mL) and cooled to-5 ℃. To the fuming HN0 in 30 minutes₃(1.5mL) was added dropwise. During this addition, the temperature of the reaction was kept below 0 ℃. Thereafter, the reaction mixture was stirred at ice temperature for 1 hour and at room temperature for 5 hours. A yellow precipitate formed and the reaction mixture was poured into cold water. The precipitate was collected by filtration, washed with cold water (2.0mL), and dried at room temperature to give compound 9(231mg, yield 36.5%) as a pure yellow solid.

The structure of the single crystal of compound 9 is shown in FIG. 18, the DSC diagram is shown in FIG. 19, the NMR spectrum is shown in FIG. 20, and the NMR spectrum is shown in FIG. 21.

< example 5 >

The performances of the energetic compounds 6-9 synthesized by the embodiment of the invention are compared with the performances of the existing explosives, namely hexogen (RDX) and octogen (HMX):

the performance of compounds 6-9 and RDX, HMX are compared as in table 1 below.

Table 1: testing and evaluation of Compounds 6-9, RDX and HMX

Compared with the existing high-performance energetic material through the properties of the 4 kinds of energetic compounds containing oxidized furazan rings. The performance of the 4 energetic compounds containing furazan oxide rings can be known by comparing the detonation velocity D with the detonation pressure P:

energetic compounds

6, 7 and 9 are superior to RDX, and 6 is close to HMX; while 7 and 9 are also superior to HMX and are good high explosives. 8 is close to RDX, and the sensitivity of the

energetic salt

6, 7 and 8 is far better than that of RDX and HMX. The neutral nitrating compound 9 has very high detonation performance, and from the aspect of the performance, the neutral nitrating compound has the highest detonation performance in the currently known neutral nitrating compounds, and has great potential to be used as a propellant oxidizer.

The formation enthalpy and the density jointly determine the detonation velocity and the detonation pressure, the detonation velocity and the detonation pressure are the key of the performance of the energetic material, and the higher the detonation velocity and the detonation pressure, the better the detonation velocity and the detonation pressure; the impact sensitivity and the friction sensitivity are the key for using, the higher the bluntness, the better the stability of the bluntness energetic material, and the safer the use and the storage.

According to the invention, a series of energetic salts containing furazan rings are obtained by introducing geminal dinitro and the furazan ring-containing framework into an oxadiazole ring energetic framework, and then a neutral nitrated compound is obtained by nitration of ammonium salt. The structure is confirmed by nuclear magnetism, mass spectrum and single crystal, the nitrogen oxygen content of the compound is improved, and the density, oxygen balance and detonation performance of energetic molecules are improved. The invention also discloses a method for preparing the nitrone energetic compound containing the furazan ring or the available salt thereof, which starts from the known available raw materials, realizes the synthesis of the novel nitrone energetic compound containing the furazan ring or the available salt thereof through multi-step reactions, and provides a new thought for synthesizing the novel high-energy-density energetic compound in the energetic material.

The furoxan ring has higher oxygen balance, and the introduction of coordinated oxygen can effectively improve the density, so that the nitrone compound has more advantages in the application of energetic materials.

While embodiments of the invention have been disclosed above, it is not intended to be limited to the uses set forth in the specification and examples. It can be applied to all kinds of fields suitable for the present invention. Additional modifications will readily occur to those skilled in the art. It is therefore intended that the invention not be limited to the exact details and illustrations described and illustrated herein, but fall within the scope of the appended claims and equivalents thereof.

Claims

1. An oxafurazan ring-containing nitrazepine energetic compound, or a useful salt thereof, the energetic compound having a structure as shown in formula (I):

2. An oxidized furazan ring-containing nitrated energetic compound or a usable salt thereof as claimed in claim 1, wherein when R is₂And R₃Is composed of

The energetic compound has an unsalified structure.

3. An oxidofurazan ring-containing nitrated energetic compound or a usable salt thereof as claimed in claim 1, wherein R₁is-NH-or-N ═ N-.

4. The nitrofurazan ring containing oxidized energetic compound or the usable salt thereof as claimed in claim 1, wherein when R is₂And R₃Is composed of

Energetic compoundThe salt is a salt forming structure, and the salt is ammonium salt, hydroxylamine salt or hydrazine salt.

5. A process for preparing the oxidized furazan ring-containing nitroxide-containing compound of any one of claims 1 to 4 or a usable salt thereof, comprising the steps of:

step one, synthesis of intermediate compound of formula (III)

step two, synthesis of compound of formula (I)

Reacting the compound of formula (III) obtained in the first step with a basic compound, or further reacting the product obtained after the reaction of the basic compound to obtain a compound of formula (I);

6. the method of claim 5, wherein in the compound of formula (III), R₄is-N ═ N-.

7. The method according to claim 5, wherein in the second step, the basic compound is ammonia water or hydrazine hydrate.

8. The process according to claim 5, wherein in the second step, the molar ratio of the compound of formula (III) to the basic compound is 1: 10.