A multifunctional anhydrous and anaerobic reaction system and operation method

Abstract

The present invention discloses a multifunctional anhydrous and anaerobic reaction system and an operation method. The anhydrous and anaerobic reaction system includes a reaction flask, a connecting tube, a narrow neck and a storage tube; the opening of the reaction flask is communicated with the opening of the storage tube through the connecting tube and the narrow neck. The connecting tube is a straight tube, and the reaction flask and the storage tube are respectively located at both ends of the connecting tube. A magnetic stir bar is arranged in the reaction flask. Two branch tubes are arranged along the length direction of the connecting tube. A high-vacuum valve A and a high-vacuum valve B are respectively installed on the two branch tubes, and the high-vacuum valve A is located on the side close to the reaction flask. A filter that completely covers the cross section of the connecting tube is arranged in the connecting tube and is located between the two branch tubes. The anhydrous and anaerobic reaction system of the present invention has a reasonable structural design, good airtightness, is simple to operate and has low cost. It can be applied to reduction reactions involving alkali metals and the preparation of metal organic complexes, etc. It can avoid the extra contact of products with air during the experiment, and has the function of filtering and separating products without contacting air, and has good application prospects.

Description

Technical Field

[0001] The present invention relates to the field of chemical technology, and relates to a multifunctional anhydrous and anaerobic reaction system and an operation method. Background Art

[0002] In various experiments involving chemical synthesis, especially organometallic reactions, anhydrous and anaerobic reaction conditions are often required. Special instruments or anhydrous and anaerobic operation techniques must be used, otherwise the target product cannot be obtained. The key to anhydrous and anaerobic operation is to avoid contact between sensitive materials and oxygen and moisture during the reaction and post-treatment processes. This requires all instruments to be fully dried, the chemical reagents used must not contain oxygen and water, the reaction system needs to be isolated from air and protected with high-purity inert gas.

[0003] Currently, in domestic and foreign laboratories, classic Schlenk flasks and Schlenk techniques are generally used for anhydrous and anaerobic reactions, that is, anhydrous and anaerobic operations are achieved on a Schlenk flask with a double manifold. However, since these flasks are generally coated with vacuum grease at the bottle stopper to isolate the system from air, during a long-term reaction, a small amount of air may enter the system due to the loosening of the bottle stopper, and the vacuum grease may be carried into the reaction system by the volatilized solvent, affecting the reaction purity and progress. In addition, for reactions involving carbanions or free radicals, the disadvantages of this reaction method are great, because filtering with a double-headed needle will cause sample decomposition, so it is very difficult to achieve filtration or column chromatography.

[0004] In summary, it is extremely meaningful to develop an anhydrous and anaerobic reaction system without vacuum grease, which can avoid air entry during the reaction process and can achieve filtration or column chromatography. Summary of the Invention

[0005] Due to the above-mentioned defects in the prior art, the present invention provides an anhydrous and anaerobic reaction system that can efficiently complete anhydrous and anaerobic reaction operations, has no vacuum grease, has a very low probability of contacting air during the operation process, and has multifunctions such as filtration or column chromatography. Specifically, it is a multifunctional anhydrous and anaerobic reaction system and an operation method, which overcomes a series of problems such as vacuum grease pollution in the current mainstream anhydrous and anaerobic reaction operations, inability to be applied to sensitive systems (such as insufficient airtightness due to silicone grease sealing resulting in oxygen ingress, etc.), and inability to filter or perform column chromatography.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A multifunctional anhydrous and anaerobic reaction system includes a reaction flask, a connecting tube, a narrow neck, a storage tube, a magnetic stir bar, and a filter;

[0008] The opening of the reaction flask is connected to the opening of the storage tube through a connecting pipe and a narrow neck. The connecting pipe is a straight pipe. The reaction flask and the storage tube are located at both ends of the connecting pipe respectively. A magnetic stir bar is provided in the reaction flask. Two branch pipes are provided in the length direction of the connecting pipe. A high-vacuum valve A and a high-vacuum valve B are respectively installed on the two branch pipes, and the high-vacuum valve A is located on the side close to the reaction flask. A filter that completely covers the cross-section of the connecting pipe is provided in the connecting pipe, and the filter is located between the two branch pipes.

[0009] The above-mentioned multi-functional anhydrous and anaerobic reaction system can be applied to reduction reactions involving alkali metals, and the preparation of various metal-organic complexes, etc. After evacuating and replacing the inert gas more than three times, the reaction starting materials are put into the reaction flask. After the reaction in the reaction flask for a certain period of time, the pressure of the system can be adjusted through a double-tube system, so that the reaction mixture is filtered through the filter to the other end (i.e., the storage tube). Then, in an inert atmosphere, a poor solvent can be added above the filtered filtrate. Subsequently, the high-vacuum valve at the reaction end is used for decompression, and then the narrow neck is directly burned off by a flame torch to seal the storage tube to grow crystals, avoiding post-treatment and re-exposure of the product to air during the crystal growth process.

[0010] The multi-functional anhydrous and anaerobic reaction system of the present invention has a reasonable structural design. Using high-vacuum valves as the communication ports with the outside world, it is an integrated glass sintering system. There is no need to use high-vacuum silicone grease, avoiding contamination, and having excellent airtightness. The ingenious design of the high-vacuum valves at both ends of the filter can simplify the operation. At the same time, the reaction mixture can be directly filtered in a timely manner after the reaction. A storage tube is also provided to facilitate the storage of the product. After burning off the narrow neck, the storage tube can be used as a container for the next step of crystal growth, organically integrating the subsequent steps of the anhydrous and anaerobic reaction operation. It can not only simplify the operation and improve efficiency, but also avoid additional exposure of the product to air, and has great application prospects.

[0011] As a preferred technical solution:

[0012] For a multi-functional anhydrous and anaerobic reaction system as described above, the filter is a filtering device such as a glass sand core, a silica gel column, or a porous ceramic.

[0013] For a multi-functional anhydrous and anaerobic reaction system as described above, the magnetic stir bar is a magnetic stir bar with full glass coverage or a polytetrafluoroethylene magnetic stir bar.

[0014] For a multi-functional anhydrous and anaerobic reaction system as described above, the anhydrous and anaerobic reaction system is an integrally sintered glass device and the glass thickness of the system ≥ 1.5 mm, with extremely high airtightness. The operation method can be applied to reaction systems that are extremely sensitive to water and oxygen. The glass thickness of the system can ensure the safety of the reaction process.

[0015] A multifunctional anhydrous and anaerobic reaction system as described above, wherein the high-vacuum valve A and the high-vacuum valve B are sealed with plugs wrapped in polytetrafluoroethylene to achieve high airtightness, and can be used to adjust the pressure of the system and add materials.

[0016] A multifunctional anhydrous and anaerobic reaction system as described above, wherein the high-vacuum valve A and the high-vacuum valve B are connected to a double manifold through a gas extraction joint.

[0017] The present invention also provides an operation method for a multifunctional anhydrous and anaerobic reaction system as described above, comprising the following steps:

[0018] (1) Construct an anhydrous and anaerobic reaction environment for the reaction system by vacuum pumping and filling with inert gas;

[0019] (2) Put the reactants into the reaction flask through the high-vacuum valve A, and the reactants react in the reaction flask;

[0020] (3) After the reaction is completed, adjust the air pressure in the reaction system through the high-vacuum valve B, and the reaction mixture flows into the storage tube through filtration by a filter;

[0021] (4) Seal the storage tube by burning off the thin neck.

[0022] The above operation method is convenient to operate, does not need to be carried out in an anhydrous and anaerobic glove box, and has a low risk of contacting air during the process; it has strong operability, can be recycled, has low requirements for equipment, reduces the experimental difficulty and reaction cost, and can be widely promoted and applied in large-scale industry, laboratories, and has good application prospects.

[0023] As a preferred technical solution:

[0024] In the operation method as described above, the vacuum pumping and filling with inert gas in step (1) are repeated more than three times.

[0025] In the operation method as described above, before step (4), a poor solvent is slowly added to the storage tube through the high-vacuum valve B under the protection of an inert gas to grow crystals.

[0026] In the operation method as described above, the burning off of the thin neck is carried out using a flame spray gun.

[0027] The above technical solutions are only a feasible technical solution of the present invention, and the protection scope of the present invention is not limited thereto. Those skilled in the art can reasonably adjust the specific design according to actual needs.

[0028] The above invention has the following advantages or beneficial effects:

[0029] (1)The multi-functional anhydrous and anaerobic reaction system of the present invention has a reasonable structural design. Using high-vacuum valves as the communication ports with the outside world, its integrated glass sintering system does not require high-vacuum silicone grease for sealing, avoiding contamination caused by silicone grease and having excellent airtightness;

[0030] (2)The multi-functional anhydrous and anaerobic reaction system of the present invention is equipped with a filter, which can directly filter in a timely manner after the reaction or perform column chromatography. It also has a storage tube for convenient storage of products. After burning off the thin neck, the storage tube can be used as a container for the next step of crystal growth, organically integrating the subsequent steps of the anhydrous and anaerobic reaction operation. This not only simplifies the operation and improves efficiency but also avoids the product coming into extra contact with air;

[0031] (3)The operation method of the present invention has strong operability, can be recycled, has low requirements for equipment, reduces the experimental difficulty and reaction cost, and can be widely promoted and applied in large-scale industries, laboratories, etc., with good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] By reading the detailed description of the non-restrictive embodiments with reference to the following drawings, the present invention and its features, shape, and advantages will become more obvious. The same reference numerals indicate the same parts in all the drawings. The drawings are not drawn to scale, and the emphasis is on showing the gist of the present invention.

[0033] Figure 1 is a structural schematic diagram of the multi-functional anhydrous and anaerobic reaction system of the present invention;

[0034] Figure 2 is a product photo of preparing sodium salt of indeno[1,2-b]fluorene dianion crystal using the multi-functional anhydrous and anaerobic reaction system of the present invention;

[0035] Figure 3 is a schematic diagram of the single crystal structure of sodium salt of indeno[1,2-b]fluorene dianion;

[0036] Figure 4 is a schematic diagram of the single crystal structure of potassium salt of triphenylbenzene dianion;

[0037] Figure 5 is a schematic diagram of the single crystal structure of potassium salt of [4]cyclo[4]helicene tetraanion;

[0038] Among them, 1 is a magnetic stir bar, 2 is a reaction flask, 3 is a filter, 4 is high-vacuum valve A, 5 is high-vacuum valve B, 6 is a thin neck, and 7 is a storage tube. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but it is not intended to limit the present invention. In the following embodiments, the reagents, materials, and instruments used, unless otherwise specified, are all conventional reagents, conventional materials, and conventional instruments, which can be commercially purchased, and the reagents involved can also be synthesized by conventional synthesis methods.

[0040] The multifunctional anhydrous and anaerobic reaction system involved in the following embodiments, as Figure 1 shown, is an integrally sintered glass device, which includes a magnetic stir bar 1, a reaction flask 2, a filter 3, a high-vacuum valve A 4, a high-vacuum valve B 5, a neck 6, and a storage tube 7;

[0041] The opening of the reaction flask 2 is communicated with the opening of the storage tube 7 through a connecting tube and the neck 6. The connecting tube is a straight tube. The reaction flask 2 and the storage tube 7 are located at both ends of the connecting tube respectively. A magnetic stir bar 1 (specifically a glass magnetic stir bar) is provided in the reaction flask 2. Two branch tubes are provided in the length direction of the connecting tube. The high-vacuum valve A 4 and the high-vacuum valve B 5 are respectively installed on the two branch tubes, and the high-vacuum valve A 4 is located on the side close to the reaction flask 2. A filter 3 (specifically a glass frit) that completely covers the cross-section of the connecting tube is provided in the connecting tube, and the filter 3 is located between the two branch tubes. The high-vacuum valve A 4 and the high-vacuum valve B 5 are sealed with plugs wrapped with polytetrafluoroethylene. The high-vacuum valve A 4 and the high-vacuum valve B 5 are connected to a double manifold through a gas sampling adapter.

[0042] Example 1

[0043] An operation method for preparing sodium naphthalenide anion salt crystals using a multifunctional anhydrous and anaerobic reaction system includes the following steps:

[0044] (1) Repeatedly evacuating and filling with an inert gas three times to construct an anhydrous and anaerobic reaction environment;

[0045] (2) Add anhydrous and anaerobic tetrahydrofuran (3.0 mL), alkali metal sodium (10.0 mg, 0.435 mmol), naphthalenophane (10.0 mg, 0.030 mmol, sublimation purification), and 18-crown-6 crown ether (8.1 mg, 0.031 mmol) into the reaction flask through the high-vacuum valve A. After stirring for 12 hours (i.e., reacting for 12 hours), filter the reactants into the storage tube by adjusting the air pressure;

[0046] (3) Slowly add n-hexane above the filtrate through the high-vacuum valve B;

[0047] (4) Burn off the neck with a blowtorch, and store the sealed storage tube at 5 °C.

[0048] After storing for one week, asFigure 2 As shown, it can be seen from the figure that dark red massive crystals are deposited at the bottom of the solution. The product was characterized by single crystal X-ray diffraction technology to determine its molecular structure (as Figure 3 shown) as the sodium complex of the triindene dianion.

[0049] Example 2

[0050] An operation method for preparing the potassium salt crystal of the triphenylbenzene dianion by using a multifunctional anhydrous and anaerobic reaction system, comprising the following steps:

[0051] (1) Repeatedly evacuating and filling with inert gas three times to construct an anhydrous and anaerobic reaction environment;

[0052] (2) Add anhydrous and anaerobic tetrahydrofuran (5.0 mL), triphenylbenzene (20 mg, 0.065 mmol), and alkali metal potassium (3 mg, 0.077 mmol) into the reaction flask through the high-vacuum valve A. After stirring for 48 hours (i.e., reacting for 48 hours), filter the reactants into the storage tube by adjusting the air pressure;

[0053] (3) Slowly add n-hexane above the filtrate through the high-vacuum valve B;

[0054] (4) Burn off the thin neck with a flame torch and store the sealed storage tube at 5 °C.

[0055] After storing for one week, orange-yellow massive crystals are deposited at the bottom of the solution. The product was characterized by single crystal X-ray diffraction technology to determine its molecular structure (as Figure 4 shown) as the potassium complex of the triphenylbenzene dianion.

[0056] Example 3

[0057] An operation method for preparing the potassium salt crystal of [4]cyclo[4]helicene tetraanion by using a multifunctional anhydrous and anaerobic reaction system, comprising the following steps:

[0058] (1) Repeatedly evacuating and filling with inert gas three times to construct an anhydrous and anaerobic reaction environment;

[0059] (2) Add anhydrous and anaerobic tetrahydrofuran (5.0 mL), [4]cyclo[4]helicene (1.0 mg, 0.0011 mmol), and metal potassium (4.0 mg, 0.103 mmol) into the reaction flask through the high-vacuum valve A. After stirring for 48 hours (i.e., reacting for 48 hours), filter the reactants into the storage tube by adjusting the air pressure;

[0060] (3) Slowly add n-hexane above the filtrate through the high-vacuum valve B;

[0061] (4) Use a flame spray gun to burn off the narrow neck and store the sealed storage tube at 25°C.

[0062] After one week of storage, black block crystals were deposited at the bottom of the solution. The product was characterized by single crystal X-ray diffraction to determine its molecular structure (e.g. Figure 5 (shown) is the potassium complex of the negative tetravalent anion of [4]cyclo[4]helicene.

[0063] It can be seen from the examples of Examples 1 to 3 that the multifunctional anhydrous and oxygen-free reaction system of the present invention has a reasonable structural design, uses a high vacuum valve as a connection port with the outside world, and its integrated glass sintering system does not require high vacuum silicone grease sealing, thereby avoiding the pollution caused by silicone grease, and has excellent air tightness, which can simplify the operation; a filter is provided, which can be directly filtered or passed through a column in time after the reaction, and a storage tube is provided to facilitate the storage of the product. After the thin neck is burned off, the storage tube can be used as a container for the next step of crystal growth, and the subsequent links of the anhydrous and oxygen-free reaction operation are organically integrated, which can not only simplify the operation and improve the efficiency, but also avoid the product from additionally contacting the air; the operation method has strong operability, can be recycled, has low requirements on equipment, reduces the experimental difficulty and reaction cost, can be promoted and applied on a large scale in industry and laboratories, and has good application prospects.

[0064] Those skilled in the art should understand that those skilled in the art can implement variations by combining the prior art and the above embodiments, which will not be described in detail here. Such variations do not affect the essential content of the present invention, and will not be described in detail here.

[0065] The above describes the preferred embodiments of the present invention. It should be understood that the present invention is not limited to the above-mentioned specific embodiments, and the devices and structures that are not described in detail should be understood to be implemented in a common manner in the art; any technician familiar with the art can use the above-disclosed methods and technical contents to make many possible changes and modifications to the technical solutions of the present invention without departing from the scope of the technical solutions of the present invention, or modify them into equivalent embodiments of equivalent changes, which does not affect the essential content of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention are still within the scope of protection of the technical solutions of the present invention.

Claims

1. A multifunctional anhydrous and anaerobic reaction system, characterized in that, It includes a reaction flask, a connecting tube, a narrow neck, a storage tube, a magnetic stir bar, and a filter; The opening of the reaction flask communicates with the opening of the storage tube through the connecting tube and the narrow neck. The connecting tube is a straight tube. The reaction flask and the storage tube are respectively located at both ends of the connecting tube. A magnetic stir bar is provided in the reaction flask. Two branch tubes are provided in the length direction of the connecting tube. A high-vacuum valve A and a high-vacuum valve B are respectively installed on the two branch tubes, and the high-vacuum valve A is located on the side close to the reaction flask. A filter that completely covers the cross-section of the connecting tube is provided in the connecting tube, and the filter is located between the two branch tubes.

2. The multifunctional anhydrous and anaerobic reaction system according to claim 1, characterized in that, The filter is a glass sand core, a silica gel column, or a porous ceramic.

3. The multifunctional anhydrous and anaerobic reaction system according to claim 1, wherein The magnetic stir bar is a glass fully-covered magnetic stir bar or a polytetrafluoroethylene magnetic stir bar.

4. A multifunctional anhydrous and anaerobic reaction system according to claim 1, wherein, The anhydrous and anaerobic reaction system is an integrally sintered glass device, and the glass thickness of the system is ≥1.5 mm.

5. A multifunctional anhydrous and anaerobic reaction system according to claim 1, characterized in that, The high-vacuum valve A and the high-vacuum valve B are sealed with plugs wrapped with polytetrafluoroethylene.

6. The multifunctional anhydrous and anaerobic reaction system according to claim 1, wherein, The high-vacuum valve A and the high-vacuum valve B are connected to a double manifold through a gas sampling adapter.

7. The operating method of a multifunctional anhydrous and anaerobic reaction system according to any one of claims 1 to 6, characterized in that, It includes the following steps: (1) By evacuating and filling with an inert gas, an anhydrous and anaerobic reaction environment of the reaction system is constructed; (2) The reactants are introduced into the reaction flask through the high-vacuum valve A, and the reactants react in the reaction flask; (3) After the reaction is completed, the air pressure in the reaction system is adjusted through the high-vacuum valve B, and the reaction mixture is filtered through the filter and flows into the storage tube; (4) The narrow neck is burned off to seal the storage tube.

8. The operating method according to claim 7, characterized in that, In step (1), evacuating and filling with an inert gas are repeated more than three times.

9. The operating method according to claim 7, characterized in that Before step (4), a poor solvent is slowly added to the storage tube through the high-vacuum valve B under the protection of an inert gas.

10. The operating method according to claim 7, characterized in that Step (3) is carried out under the protection of an inert gas; The burning off of the narrow neck is carried out with a flame gun.

Images