Organophosphine and its synthesis method and application

Abstract

The application discloses an organic phosphine and a synthesis method and application thereof, and relates to the technical field of organic chemical synthesis. The scheme is as follows: providing the organic phosphine with structural formula I or II; introducing phosphine and diene in a reactor replaced by inert gas, and performing reaction under the action of a catalytic or initiating system, which can be matched with a solvent, and the organic phosphine is prepared through thermal reaction or ultraviolet irradiation reaction under the condition of 0.1-12 MPa; and the use of the organic phosphine in treating phosphine-containing gas is provided. The application has the beneficial effects that: the radical addition of phosphine and diene occurs, the high proportion of phosphorus element is transferred into the organic product, the ICP-OES quantification shows that the phosphorus utilization rate is 90%-99%; the reaction condition window is wide, and is suitable for various dienes and catalytic or initiating systems, the results are stable and repeatable; the obtained organic phosphorus skeleton can be used as a phosphorus-containing structural unit for subsequent structure expansion, and the dependence on the activation route of phosphorus chloride and the corrosive byproduct path is reduced.

Description

Technical Field

[0001] This invention relates to the field of organic chemical synthesis technology, and in particular to an organophosphorus compound, its synthesis method, and its application. Background Technology

[0002] Phosphine (PH3, also known as phosphine) is a highly toxic, colorless gas with a pungent, garlic-like odor. It is spontaneously combustible in air and poses a significant risk of deflagration, making it a typical high-risk phosphorus-containing byproduct gas. In the production of phosphorus-containing chemicals such as sodium hypophosphite, phosphine is frequently released as a byproduct gas. Its generation is characterized by both continuity and fluctuation, often accompanied by inert gases, water vapor, and other entrained components, making its capture, transportation, and stable metering more difficult. Due to its high toxicity and flammable and explosive properties, phosphine is generally difficult to store and transport across regions as a conventional raw material in industry. Even when used within a plant, it requires strict engineering conditions such as inert isolation, pressure resistance, leak monitoring, and interlocking control. Therefore, the handling of phosphine at existing production sites has long been primarily focused on "safe disposal" rather than "raw material utilization."

[0003] Currently, the mainstream methods for disposing of phosphine typically involve combustion oxidation to convert it into phosphoric acid, or reaction with formaldehyde in a strongly acidic system to produce relatively stable phosphorus-containing products such as tetrahydroxymethylphosphine sulfate. These methods share the common goal of reducing the immediate safety risks of phosphine, but their technical objectives primarily focus on "removing harmful gases," rather than converting phosphine into organic phosphorus-containing intermediates that can enter the fine chemical chain. From a technical implementation perspective, combustion methods require strict control over ignition, tempering, exothermic processes, and tail gas fluctuations, and the products are mostly in the form of inorganic phosphates, making them difficult to directly support the subsequent construction of organophosphine molecules. While acidic absorption / condensation methods can form stable products, they are often affected by the corrosiveness of the reaction medium, impurity tolerance, and tail gas composition fluctuations, and the resulting product type still has a significant "structural distance" from the organophosphine skeleton, making it difficult to serve as a universal starting point for organophosphine synthesis. In other words, existing technologies can partially address safety risks at the "disposal" level, but at the "resource utilization" level, they still struggle to truly solve the key problem of "phosphine's difficulty in being converted into useful organic phosphorus-containing structural units."

[0004] Meanwhile, organophosphorus compounds have wide applications in agrochemicals, pharmaceuticals, functional materials, and textile finishing. For example, glyphosate, phosphorus-containing drugs, and phosphorus-containing finishing agents all rely on stable and scalable phosphorus-containing skeleton construction routes. In existing organophosphorus synthesis industrial systems, a common strategy is to start with phosphorus chloride reagents such as phosphorus trichloride, obtain reactive P–Cl bonds through chlorination activation, and then construct the target molecule step by step through substitution, addition, oxidation / hydrolysis. While these routes are mature, they also bring a series of unavoidable technical constraints: First, the chlorination activation process and subsequent substitution / hydrolysis are often accompanied by the generation of highly acidic and corrosive byproducts such as hydrogen chloride, placing higher demands on equipment materials, sealing systems, and exhaust gas absorption and purification. Second, corrosive byproducts and acidic environments significantly compress the range of selectable functional groups, making molecular design more complex under the coupling constraints of "target structure-process conditions," often requiring the introduction of protection / deprotection or multi-step transformations to circumvent incompatible functional groups. Third, chlorine-containing systems are sensitive to moisture, impurities, and temperature control, imposing stricter requirements on process windows and safety control during scale-up, further increasing the difficulty of organophosphorus molecule structure expansion and route development. Therefore, the reliance of traditional organophosphorus synthesis on chlorination-initiated routes not only brings the burden of handling corrosive byproducts but also technically limits the freedom and operability of organophosphorus molecule design.

[0005] Based on the above situation, the industry urgently needs a safe and controllable pathway to transform phosphine "from a hazardous byproduct gas to a usable phosphorus-containing structural unit," so that phosphine is no longer merely a risk source that must be disposed of, but can be transformed into a separable and further convertible organic phosphorus-containing intermediate, thereby improving the utilization rate of phosphine and reducing its dependence on combustion / strong acid systems in its disposal process. Simultaneously, a more direct entry point for constructing a phosphorus-containing framework is needed to alleviate the constraints of the highly corrosive byproduct pathway associated with the traditional phosphorus trichloride route, reduce the burden of tail gas treatment and material corrosion resistance, and technically reduce the limitations imposed by harsh reaction conditions, complex steps, and functional group compatibility during the expansion of organophosphorus molecular structures. To address these needs, the technical problem this invention aims to solve is: how to improve the conversion and fixation ratio of phosphine to an organic phosphorus-containing framework while ensuring controllable reaction and manageable safety boundaries, allowing phosphorus to enter the organic product system; and using this as the starting point for constructing organophosphorus molecules, reducing dependence on the phosphorus chloride activation route and the resulting corrosive byproducts and molecular design constraints. Summary of the Invention

[0006] To achieve the above-mentioned objectives and address the aforementioned technical problems, the present invention provides an organophosphine compound having the structure shown in structural formula I or structural formula II.

[0007] Structural Formula I

[0008] Structural Formula II In structural formula I and structural formula II, R1, R2, R4, R5, and R7 may be the same or different, and are respectively selected from hydrogen, C1-C18 aliphatic groups or C8-C18 aromatic groups; R3 and R6 may be the same or different, and are selected from C2-C18 aliphatic subunits or C6-C18 aromatic subunits, respectively. n≥1; when n=1, R6 can also be selected from C1~C18 aliphatic groups or C8~C18 aromatic groups.

[0009] Preferably, R1, R2, R4, R5, and R7 are each selected from at least one of hydrogen, methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, decyl, dodecyl, octadecyl, allyl, allyl, cyclohexyl, hexenyl, cyclopentenyl, 4-penten-1-yl, 4-penten-2-yl, 3-penten-1-yl, 3-penten-2-yl, 3-hexen-1-yl, 4-hexen-1-yl, 5-hexen-1-yl, 4-hexen-2-yl, 5-hexen-2-yl, 3-hexen-2-yl, 1-phenylethyl, 2-phenylethyl, 1-naphthylethyl, and 2-naphthylethyl.

[0010] Preferably, R3 and R6 may be the same or different, and are selected from at least one of 1,2-ethylene, 1,4-butylene, 2,3-butylene, 1,3-butylene, 1,5-pentaneene, 2,5-pentaneene, 1,4-pentaneene, 2,4-pentaneene, 1,6-hexaneene, 1-phenyl-1,2-ethylene, 2-phenyl-1,2-propylene, 3-phenyl-1,2-propylene, and 1-naphthyl-1,2-ethylene.

[0011] This application also provides a method for synthesizing the above-mentioned organophosphine compounds, comprising the following steps: S1 involves introducing phosphine and a diene into a pre-purged nitrogen reactor, and reacting them in the presence of a catalyst or a catalyst and a solvent at a pressure of 0.1–12 MPa. S2 reacts under reaction conditions to obtain the organophosphine compound, the reaction conditions including heating conditions and / or ultraviolet light irradiation conditions; The heating conditions are a reaction temperature of 10–200°C and a reaction time of 0.5–48 h, and the ultraviolet irradiation conditions are an ultraviolet irradiation time of 1–48 h.

[0012] Preferably, step S1 includes: The catalyst is added to the reactor in the form of a molecular sieve; Stop introducing phosphine once the preset injection rate is reached; Diene was then added to the reactor; The molar ratio of phosphine to diene is 2:1 to 1:5.

[0013] Preferably, step S1 includes: Liquid diene and catalyst or solvent, liquid diene and catalyst are pre-added to a pressure-resistant reactor purged with inert gas; Stop introducing phosphine once the preset injection rate is reached; The molar ratio of phosphine to diene is 2:1 to 1:2.

[0014] Preferably, the method further includes a two-stage reaction step: After the reaction of phosphine and diene is completed, olefins are introduced into the reactor and the reaction continues. The olefins are introduced until the preset amount is reached, and then the introduction is stopped.

[0015] Preferably, the catalyst is selected from one or more of concentrated sulfuric acid, platinum-based catalysts, peroxides, azo compounds, redox system catalysts that can generate free radicals, or free radical-type ultraviolet photoinitiators; Preferably, the amount of catalyst used is 0.1‰ to 10% of the molar amount of phosphine.

[0016] Preferably, the solvent is selected from at least one of water, methanol, ethanol, isopropanol, propanol, benzene, toluene, xylene, ethyl acetate, butyl acetate, acetone, and methyl ethyl ketone.

[0017] This application also provides the use of the above-mentioned organophosphine compound in the treatment of phosphine-containing gas.

[0018] The beneficial effects of the technical solution provided by this invention are as follows: 1) Phosphine is converted in a high proportion and enters the product system. Quantitative analysis of the phosphorus content in the product using ICP-OES and conversion of phosphorus molar amounts showed that approximately 90%–99% of the phosphorus added to the phosphine product entered the product. This indicates that the phosphine was effectively consumed and fixed into the organophosphine product, thus realizing the resource utilization of phosphine.

[0019] 2) The reaction pathway is universal, the conditions are wide-ranging, and the results are stable. Despite different diene substrates, different initiation / catalysis systems (peroxide, azo compound, redox system, UV photoinitiation), and both thermal and UV energy input conditions, the phosphorus utilization rate remained at a high level, indicating that the synthesis method has good adaptability and reproducibility to raw materials and process conditions.

[0020] 3) The free radical addition bonding mechanism supports the realization of the "PH3 → organophosphine skeleton" The initiation / catalysis system or ultraviolet irradiation generates free radicals, which trigger the addition of the P-H bond of phosphine to the C=C bond of the diene and chain growth, causing phosphorus to be transferred from the gas phase and stably embedded in the organic framework. This mechanism explains the high phosphorus utilization rate and the formation of stable products.

[0021] 4) Provides an entry point for constructing a phosphorus-containing framework starting from non-chlorination. This method directly involves phosphine in the construction of organophosphorus skeletons, without relying on the chlorination activation pathway starting from phosphorus trichloride. This reduces the dependence on byproducts and corrosive systems associated with chlorine-containing reaction routes from the source, thereby reducing the path constraints for subsequent organophosphorus structure expansion. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. Of course, the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0023] Example 1 Phosphine gas was introduced into a stainless steel reactor that had been pre-purified with high-purity nitrogen and contained 100 ml of anhydrous ethanol and 0.001 mol of peracetic acid. Once the absorption reached 1 mol of phosphine (34 g), the phosphine gas was stopped. Butadiene gas was then introduced, and once the amount of butadiene added reached 1 mol, the introduction of butadiene gas was stopped. The temperature was then raised to 60 °C, and the reaction time was 20 h. The reaction pressure was the pressure naturally reached by the reactor after heating. After the reaction, 1,4-butadiphosphine was obtained by distillation.

[0024] Example 2 Phosphine gas was introduced into a stainless steel reactor that had been pre-purified with high-purity nitrogen and contained 100 ml of anhydrous ethanol, 0.005 mol of peracetic acid, 0.005 mol of ferrous chloride, and 0.5 mol of 1,4-pentadiene. The gas flow was stopped once the absorption reached 1 mol of phosphine (34 g). The temperature was then raised to 80 °C, and the reaction time was 20 h. The reaction pressure was the pressure naturally reached by the reactor after heating. After the reaction, 1,5-pentadiphosphine was obtained by distillation.

[0025] Example 3 Phosphine gas was introduced into a stainless steel reactor that had been pre-purified with high-purity nitrogen and contained 100 ml of toluene, 0.005 mol of peracetic acid, 0.005 mol of ferrous chloride, and 0.5 mol of 1,4-pentadiene. The gas flow was stopped once the absorption reached 1 mol of phosphine (34 g). The temperature was then raised to 10 °C, and the reaction time was 48 h. The reaction pressure was the pressure naturally reached by the reactor after heating. 1,5-Pentadiphosphine was obtained after the reaction.

[0026] Example 4 Phosphine gas was introduced into a stainless steel reactor containing 100 ml of toluene and 0.01 mol of azobisisobutyronitrile (AIBN) that had been pre-purified with high-purity nitrogen. The introduction of phosphine gas was stopped once 1 mol (34 g) of phosphine was absorbed. Then, 1 mol of butadiene was added, and the temperature was raised to 40°C. The reaction time was 10 h, and the reaction pressure was the pressure naturally reached by the reactor after heating. After the reaction was complete, ethylene gas was introduced to raise the pressure to 10 MPa, and the reaction continued until 1 mol of ethylene was consumed, at which point the reaction was terminated to obtain 2,3-di(ethylphosphino)butane.

[0027] Example 5 Phosphine gas was introduced into a stainless steel reactor that had been pre-purified with high-purity nitrogen, containing 0.4 mol of isoprene and 0.01 mol of dicumyl peroxide. Once the absorption reached 0.2 mol of phosphine, the introduction of phosphine gas was stopped. The temperature was then raised to 200℃, and the reaction time was 0.5 h. The reaction pressure was the pressure naturally reached by the reactor after heating. After separation, 2-methyl-1,4-bis(bis(3-methylbut-1-en-4-yl)phosphino)butane was obtained.

[0028] Example 6 Phosphine gas was introduced into a stainless steel reactor that had been pre-purified with high-purity nitrogen, containing 0.4 mol of isoprene and 0.01 mol of dicumyl peroxide. Once the absorption reached 0.2 mol of phosphine, the gas flow was stopped. The temperature was then raised to 150°C, and the reaction time was 20 hours. The reaction pressure was the pressure naturally reached by the reactor after heating. After separation, 2-methyl-1,4-bis(bis(3-methylbut-1-en-4-yl)phosphino)butane was obtained.

[0029] Example 7 Phosphine gas was introduced into a reactor that had been pre-purified with high-purity nitrogen, containing 1 mol of isoprene and 0.01 mol of acetone. Once the absorption reached 0.5 mol of phosphine, the gas flow was stopped. The reaction was then initiated under ultraviolet light for 20 hours. After separation, 2-methyl-1,4-bis(bis(3-methylbut-1-en-4-yl)phosphino)butane was obtained.

[0030] Example 8 Phosphine gas was introduced into a stainless steel reactor containing 1 mol of isoprene and 0.01 mol of ammonium persulfate, which had been pre-purified with high-purity nitrogen. Once the absorption reached 0.6 mol of phosphine, the gas flow was stopped. The temperature was then raised to 150°C, and the reaction time was 20 hours. The reaction pressure was the pressure naturally reached by the reactor after heating. After separation, 2-methyl-1,4-bis(bis(3-methylbut-1-en-4-yl)phosphino)butane was obtained in [yield missing].

[0031] Example 9 Phosphine gas was introduced into a reactor containing 1 mol of isoprene and 0.01 mol of photoinitiator 1173, which had been pre-purified with high-purity nitrogen. Once the absorption reached 0.8 mol of phosphine, the gas flow was stopped. The reaction was then initiated under ultraviolet light and carried out for 20 hours. The resulting product, 3-methyl-3-buten-1-ylphosphine, was obtained after separation.

[0032] Example 10 Phosphine gas was introduced into a stainless steel reactor containing 1 mol of hexadiene and 0.02 mol of dicumyl peroxide, which had been pre-purified with high-purity nitrogen. Once the absorption reached 0.5 mol of phosphine, the gas flow was stopped. The temperature was then raised to 200°C, and the reaction time was 6 hours. The reaction pressure was the pressure naturally reached by the reactor after heating. After the reaction, bis(hex-1-en-6-yl)phosphine was obtained through separation.

[0033] Example 11 Phosphine gas was introduced into a stainless steel reactor that had been pre-purified with high-purity nitrogen and contained 1 mol of 1,6-octadiene and approximately 0.002 mol of platinum chloride-loaded molecular sieve. Once the absorption reached 0.5 mol of phosphine, the gas flow was stopped. The temperature was then raised to 200°C, and the reaction time was 6 hours. The reaction pressure was the pressure naturally reached by the reactor after heating. After the reaction, bis(oct-1-en-7-yl)phosphine was obtained through separation.

[0034] Example 12 Phosphine gas was introduced into a stainless steel reactor that had been pre-purified with high-purity nitrogen, containing 1 mol of butadiene and approximately 0.006 mol of platinum chloride-loaded molecular sieve. Once the absorption reached 0.5 mol of phosphine, the gas flow was stopped. The temperature was then raised to 200°C, and the reaction time was 6 hours. The reaction pressure was the pressure naturally reached by the reactor after heating. After the reaction, bis(but-1-en-4-yl)phosphine was obtained through separation.

[0035] Experimental test: Phosphorus element test The phosphorus content in the product is tested by ICP-OES, and the molar mass of phosphorus in the product is calculated by converting it with the actual mass of the product. The utilization rate of phosphorus can then be obtained.

[0036] Table 1 Test Data

[0037] Table 1 shows that under different substrate types (straight-chain dienes, branched-chain dienes, and longer-chain dienes), different reaction medium forms (solvent participation or liquid dienes as the reaction medium), and different energy input methods and initiation / catalysis systems (peroxide or azo system under thermal conditions, redox system, ultraviolet irradiation system, and supported metal catalysis system), the actual molar amount of phosphorus in the product consistently maintains a high correlation with the molar amount of phosphine added. This indicates that phosphine is continuously consumed and converted into separable organic phosphorus-containing products during the reaction process, rather than remaining in large quantities as unreacted gas or being lost as inorganic byproducts. In particular, some systems can maintain a high phosphorus transfer ratio even at lower temperatures or within shorter time windows, indicating that the reaction network does not depend on a single harsh condition to proceed. The following mechanistic explanation can be derived by combining the commonalities of different implementation paths: Regardless of whether thermal initiation or UV photoinitiation is used, the core of the system lies in forming a stable and continuous free radical flux, enabling the P–H bond of phosphine to generate phosphorus-containing free radicals and add to the C=C bond of the diene. Subsequently, phosphorus is "locked" into the organic framework through chain growth and chain transfer. When a redox system or supported metal catalysis is used, free radical generation / activation and surface active sites can further promote the initial addition and subsequent propagation processes, thereby reducing the probability of phosphorus diverting to side reaction pathways. On the other hand, the extended reaction of introducing olefins in the second stage can still maintain a high level of phosphorus transfer, indicating that after the formation of phosphorus-containing intermediates or phosphorus-containing frameworks, the subsequent capture and structural extension of olefins do not significantly disrupt the organic fixation trend of phosphorus. Instead, it demonstrates the feasibility of the system in structural extension and its robustness to process disturbances.

[0038] Overall, the above data collectively demonstrate that the synthetic system can achieve a high conversion rate of phosphine and efficient utilization of phosphorus under various reaction conditions and catalytic / initiation modes. The key reason is that the free radical addition-chain propagation mechanism continuously drives the P–H to P–C bond formation, enabling phosphorus to preferentially enter the target organic phase product rather than be lost in the gas phase or other by-product forms.

[0039] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An organophosphorus compound, characterized in that, The organophosphine compound has the structure shown in structural formula I or structural formula II; Structural Formula I Structural Formula II In structural formula I and structural formula II, R1, R2, R4, R5, and R7 may be the same or different, and are respectively selected from hydrogen, C1-C18 aliphatic groups or C8-C18 aromatic groups; R3 and R6 may be the same or different, and are selected from C2-C18 aliphatic subunits or C6-C18 aromatic subunits, respectively. n≥1; when n=1, R6 can also be selected from C1~C18 aliphatic groups or C8~C18 aromatic groups.

2. The organophosphorus compound according to claim 1, characterized in that, R1, R2, R4, R5, and R7 are each selected from at least one of hydrogen, methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, decyl, dodecyl, octadecyl, allyl, allyl, cyclohexyl, hexenyl, cyclopentenyl, 4-penten-1-yl, 4-penten-2-yl, 3-penten-1-yl, 3-penten-2-yl, 3-hexen-1-yl, 4-hexen-1-yl, 5-hexen-1-yl, 4-hexen-2-yl, 5-hexen-2-yl, 3-hexen-2-yl, 1-phenylethyl, 2-phenylethyl, 1-naphthylethyl, and 2-naphthylethyl.

3. The organophosphorus compound according to claim 1, characterized in that, R3 and R6 may be the same or different, and are selected from at least one of 1,2-ethylidene, 1,4-butylidene, 2,3-butylidene, 1,3-butylidene, 1,5-pentanediol, 2,5-pentanediol, 1,4-pentanediol, 2,4-pentanediol, 1,6-hexanediol, 1-phenyl-1,2-ethylidene, 2-phenyl-1,2-propylidene, 3-phenyl-1,2-propylidene, and 1-naphthyl-1,2-ethylidene.

4. A method for synthesizing the organophosphorus compound according to any one of claims 1 to 3, characterized in that, Includes the following steps: S1 involves introducing phosphine and a diene into a pre-purged nitrogen reactor, and reacting them in the presence of a catalyst or a catalyst and a solvent at a pressure of 0.1–12 MPa. S2 reacts under reaction conditions to obtain the organophosphine compound, the reaction conditions including heating conditions and / or ultraviolet light irradiation conditions; The heating conditions are a reaction temperature of 10–200°C and a reaction time of 0.5–48 h, and the ultraviolet irradiation conditions are an ultraviolet irradiation time of 1–48 h.

5. The synthesis method according to claim 4, characterized in that, Step S1 includes: The catalyst is added to the reactor in the form of a molecular sieve; Stop introducing phosphine once the preset injection rate is reached; Diene was then added to the reactor; The molar ratio of phosphine to diene is 2:1 to 1:

5.

6. The synthesis method according to claim 4, characterized in that, Step S1 includes: Liquid diene and catalyst or solvent, liquid diene and catalyst are pre-added to a pressure-resistant reactor purged with inert gas; Stop introducing phosphine once the preset injection rate is reached; The molar ratio of phosphine to diene is 2:1 to 1:

2.

7. The synthesis method according to claim 4, characterized in that, The method further includes a two-stage reaction step: After the reaction of phosphine and diene is completed, olefins are introduced into the reactor and the reaction continues. The olefins are introduced until the preset amount is reached, and then the introduction is stopped.

8. The synthesis method according to any one of claims 4 to 7, characterized in that, The catalyst is selected from one or more of the following: concentrated sulfuric acid, platinum-based catalysts, peroxides, azo compounds, redox system catalysts that can generate free radicals, or free radical-type ultraviolet photoinitiators; The amount of catalyst used is 0.1‰ to 10% of the molar amount of phosphine.

9. The synthesis method according to any one of claims 6 or 7, characterized in that, The solvent is selected from at least one of water, methanol, ethanol, isopropanol, propanol, benzene, toluene, xylene, ethyl acetate, butyl acetate, acetone, and methyl ethyl ketone.

10. Use of the organophosphorus compound according to any one of claims 1 to 3 in the treatment of phosphine-containing gas.

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