Synthesis method of 1, 1 '-dihydroxy-5, 5'-bistetrazole sodium salt hydrate

Abstract

The invention relates to the technical field of organic synthesis, in particular to a synthesis method of a 1, 1 '-dihydroxy-5, 5'-bistetrazole sodium salt hydrate, which comprises the following steps: S1, carrying out substitution reaction on dichloroglyoxime and trimethylsilyl azide in a polar solvent to generate diazido glyoxime; after the reaction is finished, directly cooling and carrying out next-step reaction; s2, putting strong acid ion exchange resin as a solid acid catalyst into the reaction system, and carrying out cyclization reaction on diazido glyoxime to generate 1, 1 '-dihydroxy-5, 5'-bistetrazole; after the reaction is finished, carrying out solid-liquid separation, recovering the solid acid catalyst, and carrying out next-step reaction on the separated liquid phase; s3, an alkaline sodium salt aqueous solution is added into a liquid phase obtained after solid-liquid separation for a neutralization reaction, cooling is conducted, crystals are separated out, crystals are dried, and then the 1, 1 '-dihydroxy-5, 5'-bistetrazole sodium salt hydrates.The synthesis method is high in safety, environmentally friendly, mild in reaction condition and suitable for industrial production.

Description

Technical Field

[0001] The invention relates to the technical field of organic synthesis, and in particular to a method for synthesizing 1,1'-dihydroxy-5,5'-bitetrazolium sodium salt hydrate. Background Art

[0002] Tetrazolyl compounds are a typical representative of azole compounds. In addition to the advantages of high energy of the azole ring, they also have good thermal stability and acid-base stability due to their aromatic planar stable structure. The tetrazolyl ring has good compatibility, and different groups can be introduced to modify the tetrazolyl ring to regulate its sensitivity and energy level. Tetrazolyl products can be widely used in electronic chemicals according to the structural rigidity and acid-base properties of the product by adjusting the specific steric relationship between the N atom on the tetrazolyl ring and the corresponding substituent. Tetrazolyl can be used as a key raw material for regulating the acidity and alkalinity in electronic information materials.

[0003] As the demand for display panels continues to increase, display panels are increasingly used in computers, mobile phones, automobiles, home appliances and other fields. The market demand for 1,1'-dihydroxy-5,5'-bitetrazolium sodium salt hydrate (product structure shown below) is increasing. At the same time, the product quality requirements are high, requiring batch quality stability of the product.

[0004]

[0005] According to inquiries, according to the current reports on the synthesis method of 1,1'-dihydroxy-5,5'-bis tetrazole sodium salt hydrate, the synthesis method mainly uses dichloroethylene dioxime and sodium azide to react in DMF solvent to generate diazidoethylene dioxime, and then generates 1,1'-dihydroxy-5,5'-bis tetrazole under the action of concentrated sulfuric acid (this step is usually carried out at a low temperature of 0-10°C), and then generates 1,1'-dihydroxy-5,5'-bis tetrazole sodium salt under the action of sodium hydroxide. This reaction process uses dichloroethylene dioxime and sodium azide to react, and then uses concentrated sulfuric acid for cyclization reaction. Unreacted sodium azide will generate highly toxic chemicals hydrazoic acid under the action of concentrated sulfuric acid. Hydrazoic acid is a colorless, volatile liquid with extremely strong toxicity and explosiveness. Sodium azide as a raw material is also a highly toxic and highly explosive compound, which is very harmful to the environment and human health. The purchase, transportation, storage and handling of sodium azide require strict safety measures, which increases storage and management costs. The reaction requires a large amount of concentrated sulfuric acid, which is highly corrosive and oxidizing. The cost of waste acid treatment is high and it is not environmentally friendly. The second step of the reaction must be carried out at 0-10°C, which is much lower than room temperature. The reaction conditions are harsh and require additional costs to strictly control the low temperature environment.

[0006] In summary, the above-mentioned synthesis process is dangerous, not environmentally friendly, and has high cost, and is not suitable for industrial production. Summary of the invention

[0007] 1. Technical issues to be resolved

[0008] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a method for synthesizing 1,1'-dihydroxy-5,5'-bistetrazole sodium salt hydrate, which avoids the use of highly toxic and highly explosive sodium azide and highly corrosive sulfuric acid as raw materials, and the problem of generating volatile, highly toxic and explosive hydrazoic acid under acidic conditions, so that the synthesis process of 1,1'-dihydroxy-5,5'-bistetrazole sodium salt hydrate is safer, controllable and environmentally friendly, and more suitable for industrial production and application.

[0009] (II) Technical solution

[0010] The present invention provides a method for synthesizing 1,1'-dihydroxy-5,5'-bistetrazole sodium salt hydrate, comprising the following steps:

[0011] S1, performing a substitution reaction between dichloroglyoxime and trimethylsilyl azide in a polar solvent to generate diazido-glyoxime; after the reaction is completed, directly cooling the mixture to perform the next step of reaction;

[0012] S2, adding a strong acid ion exchange resin as a solid acid catalyst into the reaction system of S1 to cause a cyclization reaction of diazido-glyoxime to generate 1,1'-dihydroxy-5,5'-bistetrazole; after the reaction is completed, the solid-liquid separation is performed, the solid acid catalyst is recovered, and the separated liquid phase is subjected to the next reaction;

[0013] S3, adding alkaline sodium salt aqueous solution to the liquid phase obtained by solid-liquid separation in S2 for neutralization reaction, cooling, precipitating crystals, separating the crystals, and drying to obtain 1,1'-dihydroxy-5,5'-bitetrazolium sodium salt hydrate.

[0014] The above reaction process is expressed as follows:

[0015]

[0016] According to a preferred embodiment of the present invention, in S1, the molar ratio of dichloroethylenedioxime to trimethylsilyl azide is 1:2.1-2.2. Theoretically, every 2 moles of trimethylsilyl azide and 1 mole of dichloroethylenedioxime undergo a substitution reaction, and the azide replaces the chlorine in the dichloroethylenedioxime. In S1, making trimethylsilyl azide slightly excessive relative to dichloroethylenedioxime is beneficial to promoting the reaction conversion rate and product yield, so that dichloroethylenedioxime is converted into diazido-based ethylenedioxime as much as possible.

[0017] According to a preferred embodiment of the present invention, in S1, the polar solvent is at least one of DMF, acetonitrile and acetone. In the substitution reaction of trimethylsilyl azide and dichloroethylene dioxime, dichloroethylene dioxime and trimethylsilyl azide are reactants with large polarity, so the use of polar solvents is more conducive to the dissolution of dichloroethylene dioxime. In the substitution reaction, the azide anion produced by the decomposition of trimethylsilyl azide is a nucleophilic reagent, and the departure of the chlorine atom on dichloroethylene dioxime requires an appropriate environment to stabilize the generated carbon cation intermediate (even if it is only instantaneous). Polar solvents can help stabilize these charged species through their high dielectric constant, thereby accelerating the reaction process.

[0018] According to a preferred embodiment of the present invention, in S1, the reaction is carried out at 40-50°C, and the reaction time is 1-8h, preferably 2-5h.

[0019] According to a preferred embodiment of the present invention, in S2, the strongly acidic ion exchange resin is a type of high molecular polymer containing a sulfonic acid functional group, preferably Amberlite IR120 and Amberlite IRC86 of Rohm and Haas, Dowex 50WX2, Dowex 50WX4, Dowex 50WX8, Purolite C150 of Dow Chemical, Lewatit S1467 of Lanxess, domestic resin 001×7 series resin, D001 series (such as D-61 type) resin, etc. The strongly acidic ion exchange resin has a sulfonic acid group, is a spherical particle, and has a particle size range of 0.3-1.2mm. The smaller the particle size, the faster the catalytic rate. The amount of the strongly acidic ion exchange resin is 10-15% of the mass of dichloroethylene dioxime.

[0020] According to a preferred embodiment of the present invention, in S2, the reaction temperature is 50-60°C and the reaction time is 5-15h.

[0021] According to a preferred embodiment of the present invention, in S1, sampling is performed to detect whether the dichloroglyoxime in the reaction solution is completely consumed. When no dichloroglyoxime is detected, the reaction is terminated, and then the reaction solution is cooled to 10-15° C. for the next step of reaction. The cooling treatment can reduce the probability of decomposition of diazido-based glyoxime.

[0022] According to a preferred embodiment of the present invention, in S2, sampling and detection are performed. When the diazido-based glyoxime in the reaction system is consumed, it indicates that the reaction is completed, the temperature is lowered to below 25°C, and the strong acid ion exchange resin is recovered by filtration or centrifugation. The recovered strong acid ion exchange resin is regenerated by acidification and used for the next batch of reactions.

[0023] According to a preferred embodiment of the present invention, in S3, the alkaline sodium salt aqueous solution is a sodium carbonate aqueous solution or a sodium bicarbonate aqueous solution; the alkaline sodium salt aqueous solution is used to neutralize the liquid phase separated in S2 to pH 7-8. Sodium carbonate and sodium bicarbonate can provide sodium ions to form salts, and they have moderate alkalinity, avoiding the problem of strong alkali being doped in the precipitated wet crystals and decomposing at a drying temperature such as 80-90°C.

[0024] According to a preferred embodiment of the present invention, in S3, the temperature is lowered to 0-5°C, the mixture is kept warm and stirred to precipitate crystals, the crystals are recovered by filtration or centrifugation, and the crystals are dried at 80-90°C to obtain a finished product of 1,1'-dihydroxy-5,5'-bitetrazolium sodium salt hydrate.

[0025] (III) Beneficial effects

[0026] The technical effects of the present invention include the following aspects:

[0027] (1) The present invention avoids the use of highly toxic and explosive sodium azide raw materials, so the reaction process is safer and more controllable, less dangerous, and more environmentally friendly. At the same time, it also reduces the storage cost of sodium azide and reduces the risk of improper storage or handling.

[0028] (2) The process of the present invention uses trimethylsilyl azide as a reaction raw material, which can exist stably under acidic conditions. Therefore, even if there is an excess of trimethylsilyl azide after the S1 reaction and enters the next step of the reaction, highly toxic and highly explosive hydrazoic acid will not be generated, so the reaction process is safer and less harmful to production operators; at the same time, a strong acid ion exchange resin is used as a solid acid catalyst to ensure an acidic environment without generating free acid, making the reaction process safer.

[0029] (3) The reaction temperature of S1 of the present invention is 40-50°C, and the reaction temperature of S2 is 50-60°C. There is no need to invest a large amount of refrigeration cost to maintain the reaction system in a low temperature environment of 0-10°C. Therefore, the reaction conditions are milder, the cost is lower, and it is suitable for industrial production.

[0030] (4) Using strong acid ion exchange resin as a solid acid catalyst is easy to separate and recycle, and can be reused after recycling; compared with concentrated sulfuric acid, there is no waste acid discharge, it has lower corrosiveness, is non-oxidizing, is conducive to protecting production equipment, and is more environmentally friendly. In addition, compared with concentrated sulfuric acid as a catalyst, strong acid ion exchange resin does not produce free acid, so the cyclization process of S2 can be carried out stably, and the reaction process is more gentle and controllable; the cyclization reaction at 50-60°C is more thorough and the reaction conversion rate is higher than the cyclization reaction at 0-10°C in the prior art.

[0031] (5) The reaction process produces few by-products and has a high reaction conversion rate. Compared with the 60% yield reported in the current literature, the yield of the product of the present invention can be stabilized at more than 85%, which is much higher than that reported in the existing literature. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is the H-NMR spectrum of the product 1,1'-dihydroxy-5,5'-bitetrazolium sodium salt hydrate.

[0033] Figure 2 This is the infrared spectrum of the product 1,1'-dihydroxy-5,5'-bitetrazolium sodium salt hydrate.

[0034] Figure 3 This is the HPLC spectrum of the product 1,1'-dihydroxy-5,5'-bitetrazolium sodium salt hydrate. DETAILED DESCRIPTION

[0035] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0036] The sources of the reagents used in the following examples are as follows:

[0037] Trimethylsilyl azide was commercially available 98% trimethylsilyl azide.

[0038] The dichloroglyoxime was commercially available 99% dichloroglyoxime.

[0039] Strong acid ion exchange resins are commercially available as specific types of resins.

[0040] The synthesis process of the present invention is described below in conjunction with the embodiments of the present invention.

[0041] Example 1

[0042] This embodiment provides a method for synthesizing 1,1'-dihydroxy-5,5'-bistetrazole sodium salt hydrate, comprising the following steps:

[0043] (1) Add 112L of DMF to a 300L reactor, start stirring, add 28kg of dichloroethylene dioxime under stirring, stir and dissolve, start the reactor to heat up, control the reactor temperature to 40-50°C, slowly drop 43.07kg of trimethylsilyl azide into the reactor, keep the temperature for 3h after the dropwise addition, take a sample to detect whether the dichloroethylene dioxime has reacted completely, and cool to 10-15°C. The molar ratio of dichloroethylene dioxime to trimethylsilyl azide is 1:2.1.

[0044] (2) Add 2.8 kg of strong acid ion exchange resin No. 001×7 to the reactor, start the reactor again to heat up to 50-60°C, and keep the temperature for 8 hours; take samples for testing, when the diazido glyoxime in the reaction system is consumed, it means the reaction is over, cool down to 20°C, filter and recover the strong acid ion exchange resin, and use the recovered strong acid ion exchange resin for the next batch of reactions after acidification and regeneration. The strong acid ion exchange resin accounts for 10% of the mass of dichloroglyoxime.

[0045] (3) After filtering and recovering the strong acidic ion exchange resin in step (2), a filtrate is obtained, and a sodium carbonate aqueous solution is added to the filtrate for neutralization reaction to a pH of 7-8, and the temperature is reduced to 0-5°C, and the mixture is stirred for 1 hour to precipitate crystals. The crystals are separated and dried at 80-90°C for 4 hours through a double cone drying to obtain 44.22 kg of a finished product of 1,1'-dihydroxy-5,5'-bistetrazole sodium salt hydrate, and the product yield is 86.7%. Figure 1 As shown, it is the hydrogen nuclear magnetic resonance spectrum of the finished product. Figure 2 This is the IR graph of the finished product. Figure 3 The HPLC spectrum of the finished product confirms that the product is 1,1'-dihydroxy-5,5'-bitetrazolium sodium salt hydrate.

[0046] Example 2

[0047] This embodiment provides a method for synthesizing 1,1'-dihydroxy-5,5'-bistetrazole sodium salt hydrate, comprising the following steps:

[0048] (1) Add 112 L of acetonitrile to a 300 L reactor, start stirring, add 28 kg of dichloroethylene dioxime under stirring, stir and dissolve, start the reactor to heat up, control the reactor temperature to 40-50° C., slowly drop 45.12 kg of trimethylsilyl azide into the reactor, keep the temperature for 2 hours after the dropwise addition, take a sample to detect whether the dichloroethylene dioxime has reacted completely, and cool to 10-15° C. The molar ratio of dichloroethylene dioxime to trimethylsilyl azide is 1:2.2.

[0049] (2) Add 4.2 kg of strong acid ion exchange resin D-61 to the reactor, start the reactor again to heat up to 50-60°C, and keep the temperature for 9 hours; take samples for testing, when the diazido glyoxime in the reaction system is completely consumed, it means the reaction is over, cool down to 20°C, filter and recover the strong acid ion exchange resin, and use the recovered strong acid ion exchange resin for the next batch of reactions after acidification and regeneration. The strong acid ion exchange resin accounts for 15% of the mass of dichloroglyoxime.

[0050] (3) After filtering and recovering the strongly acidic ion exchange resin in step (2), a filtrate is obtained, and a sodium carbonate aqueous solution is added to the filtrate for neutralization reaction to a pH of 7-8, and the temperature is reduced to 0-5° C., and the mixture is stirred for 1 hour to precipitate crystals. The crystals are separated and dried at 80-90° C. for 4 hours through a double cone drying to obtain 44.83 kg of a finished product of 1,1'-dihydroxy-5,5'-bistetrazole sodium salt hydrate, and the product yield is 86.9%.

[0051] Example 3

[0052] This embodiment provides a method for synthesizing 1,1'-dihydroxy-5,5'-bistetrazole sodium salt hydrate, comprising the following steps:

[0053] (1) Add 112 L of acetone to a 300 L reactor, start stirring, add 28 kg of dichloroethylene dioxime under stirring, stir and dissolve, start the reactor to heat up, control the reactor temperature to 40-50°C, slowly drop 43.07 kg of trimethylsilyl azide into the reactor, keep the temperature for 3 hours after the dropwise addition, take a sample to detect whether the dichloroethylene dioxime has reacted completely, and cool to 10-15°C. The molar ratio of dichloroethylene dioxime to trimethylsilyl azide is 1:2.1.

[0054] (2) Add 3.64 kg of strong acid ion exchange resin D-61 to the reactor, start the reactor again to heat up to 50-60°C, and keep the temperature for 8 hours; take samples for testing, when the diazido glyoxime in the reaction system is completely consumed, it means the reaction is over, cool down to 20°C, filter and recover the strong acid ion exchange resin, and use the recovered strong acid ion exchange resin for the next batch of reactions after acidification and regeneration. The strong acid ion exchange resin accounts for 13% of the mass of dichloroglyoxime.

[0055] (3) After filtering and recovering the strongly acidic ion exchange resin in step (2), a filtrate is obtained, and a sodium bicarbonate aqueous solution is added to the filtrate for neutralization reaction to a pH of 7-8, and the temperature is reduced to 0-5° C., and the mixture is stirred for 1 hour to precipitate crystals. The crystals are separated and dried at 80-90° C. for 4 hours through a double cone drying to obtain 44.36 kg of a finished product of 1,1'-dihydroxy-5,5'-bistetrazole sodium salt hydrate, and the product yield is 86.93%.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments may still be modified, or some or all of the technical features therein may be replaced by equivalents. These modifications or replacements, or the technical features in the above embodiments may be combined in the manner described in the embodiments if they do not conflict with each other, and these modifications, replacements or combinations do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for synthesizing 1,1'-dihydroxy-5,5'-bistetrazole sodium salt hydrate, characterized in that: The steps include: S1, performing a substitution reaction between dichloroglyoxime and trimethylsilyl azide in a polar solvent to generate diazido-glyoxime; after the reaction is completed, directly cooling the mixture to perform the next step of reaction; S2, adding a strong acid ion exchange resin as a solid acid catalyst into the reaction system of S1 to cause a cyclization reaction of diazido-glyoxime to generate 1,1'-dihydroxy-5,5'-bistetrazole; after the reaction is completed, the solid-liquid separation is performed, the solid acid catalyst is recovered, and the separated liquid phase is subjected to the next reaction; S3, adding an alkaline sodium salt aqueous solution to the liquid phase obtained by solid-liquid separation in S2 for neutralization reaction, cooling, precipitating crystals, separating the crystals, and drying to obtain 1,1'-dihydroxy-5,5'-bistetrazole sodium salt hydrate; The above reaction process is expressed as follows:

2. The synthesis method according to claim 1, characterized in that In S1, the molar ratio of dichloroglyoxime to trimethylsilyl azide is 1:2.1-2.

2.

3. The synthesis method according to claim 1, characterized in that In S1, the polar solvent is at least one of DMF, acetonitrile and acetone.

4. The synthesis method according to claim 1, characterized in that In S1, the reaction is carried out at 40-50°C.

5. The synthesis method according to claim 1, characterized in that In S2, the strong acid ion exchange resin is 001×7 series resin or D001 series resin, and the particle size is 0.3-1.2 mm; The dosage is 10-15% of the mass of dichloroglyoxime.

6. The synthesis method according to claim 1, characterized in that In S2, the reaction temperature is 50-60°C.

7. The synthesis method according to claim 1, characterized in that In S1, sampling is performed to detect whether the dichloroglyoxime in the reaction solution is completely consumed. When no dichloroglyoxime is detected, the reaction is completed. After that, the reaction solution is cooled to 10-15° C. for the next reaction.

8. The synthesis method according to claim 1, characterized in that In S2, sampling is performed for detection. When the diazido-glyoxime in the reaction system is completely consumed, it indicates that the reaction is finished. The temperature is lowered to below 25°C, and the strongly acidic ion exchange resin is recovered by filtration or centrifugal separation. The recovered strongly acidic ion exchange resin is regenerated by acidification and used for the next batch of reactions.

9. The synthesis method according to claim 1, characterized in that In S3, the alkaline sodium salt aqueous solution is a sodium carbonate aqueous solution or a sodium bicarbonate aqueous solution; the alkaline sodium salt aqueous solution is used to neutralize the liquid phase separated in S2 to a pH of 7-8.

10. The synthesis method according to claim 1, characterized in that In S3, the temperature is lowered to 0-5°C, the mixture is kept warm and stirred to precipitate crystals, the crystals are recovered by filtration or centrifugation, and the crystals are dried at 80-90°C to obtain a finished product of 1,1'-dihydroxy-5,5'-bitetrazolium sodium salt hydrate.

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