Preparation method of phosphorane

Abstract

The invention belongs to the field of organic phosphorus chemistry and phosphorus chemical industry, and particularly relates to a preparation method of phosphorane. Comprising the following steps: adding P4, Bu3SnH, a free radical initiator and an organic solvent into a test tube with a plug, sealing the test tube, wrapping the test tube with an aluminum foil to keep away from light, and stirring to react for a period of time; and adding acid into the reaction mixture to obtain phosphorane. The method is mild in reaction condition, good in safety and suitable for industrial production.

Description

Technical Field

[0001] The invention belongs to the fields of organophosphorus chemistry and phosphorus chemical industry, and particularly relates to a method for preparing phosphine. Background Art

[0002] Phosphine (also known as phosphine, PH3) is a linear phosphorus hydride. It is a colorless, highly toxic gas at room temperature, condensing into a liquid at -88°C and solid at -133.8°C. Due to the chemical activity of the PH bond, phosphine can undergo addition reactions with unsaturated groups and coordinate with Lewis acids and metal ions. PH3 and its derivatives act as ligands and interact with transition metals and their salts through P-Mσ coordination and d(M)-d(P) feedback π coordination to form a series of important coordination compounds. Most of these coordination compounds exhibit strong catalytic activity and are widely used in reactions such as the hydrogenation, hydrosilylation, and carbonylation of olefins. Furthermore, high-purity phosphine serves as a valuable electron gas regulator in solar energy and semiconductor materials. In grain storage, small amounts of phosphine are used as fumigants in granaries. Phosphine derivatives are also widely used in fine chemicals such as fungicides, bioreducing agents, mixed metal separation agents, flame retardants, and quantum dots. The main methods for preparing phosphine in industry at present are: 1) Byproduct method. The industrial production of sodium hypophosphite by reacting yellow phosphorus with alkali produces a large amount of PH3 as a byproduct. Patents CN201310 289015.X and CN 201210522061.5 disclose a method for preparing phosphine. Yellow phosphorus is reacted with alkali to produce phosphine, hypophosphite, and phosphite. The hypophosphite and phosphite are then treated with an inorganic acid to produce a mixture of hypophosphorous acid and phosphorous acid. The mixed acid is then thermally decomposed to produce phosphine and phosphoric acid as a byproduct. The equation is as follows: However, the NaH2PO2 in the above method will further react under alkaline conditions to generate H2 and Na3PO4, resulting in the prepared PH3 containing a certain amount of H2. In addition, the maximum yield of phosphine produced by this method is only 25%.

[0003] 2) Pyrolysis. Patent CN201310289544.X discloses a method for producing PH3 by pyrolysis of phosphorous acid. Phosphorous acid is pyrolyzed at 150°C-200°C using a platinum-on-carbon catalyst to produce high-purity PH3. CN201310290020.2 and CN201210521890.1 disclose methods for simultaneously preparing PH3 and sodium trimetaphosphate. Under nitrogen protection, a mixture of trivalent sodium phosphate and pentavalent sodium phosphate salts of a certain composition is heated at 200-400°C to undergo disproportionation and condensation reactions, yielding relatively pure PH3 and sodium trimetaphosphate. However, these methods require high temperatures, making them relatively demanding.

[0004] 3) Other methods. CN202210379814.5 discloses a method for preparing phosphine / deuterated phosphine and its derivatives. The method is to use white phosphorus and proton-containing (H + ) / deuterated protons (D + ) compounds or mixtures as reaction raw materials to efficiently prepare phosphane or deuterated phosphane. However, the above method has a long reaction time and low yield, and is not suitable for industrial production.

[0005] In view of the many problems of existing technologies such as low yield, harsh reaction conditions, and unsuitability for industrial production, there is an urgent need to develop a new preparation method for phosphine. Summary of the Invention

[0006] The present invention aims to provide a method for preparing monophosphine to solve the problems of the prior art, such as low yield, harsh reaction conditions, and unsuitability for industrial production. To solve the above technical problems, the present invention provides the following technical solutions: A method for preparing phosphine, comprising the following steps; P4, Bu3SnH, a free radical initiator, and an organic solvent are added to a stoppered test tube, which is sealed and wrapped with aluminum foil to protect from light. The reaction mixture is stirred for a period of time. Acid is then added to the reaction mixture to obtain phosphine. The reaction scheme is as follows: ; Wherein, the structure of the free radical initiator is: or .

[0007] In some embodiments, the reaction solvent is selected from benzene, toluene, 1,4-dioxane, dimethyl sulfoxide, ethanol, methanol, tert-butanol, isopropanol, dichloromethane, chloroform, dimethyl adipate, ethyl acetate, petroleum ether, ether, tetrahydrofuran, acetone, N,N - one or more of dimethylformamide, acetonitrile, cyclohexane, and n-hexane.

[0008] In some embodiments, the reaction solvent is selected from one or more of 1,4-dioxane, ethyl acetate, acetonitrile, diethyl ether and n-hexane.

[0009] In some embodiments, the acid is an inorganic acid or an organic acid; In some embodiments, the acid is HCl, HBr, HF, sulfuric acid, nitric acid, formic acid, or acetic acid; In some embodiments, the acid is preferably a solution of HCl in 1,4-dioxane; In some embodiments, the molar ratio of P4 to Bu3SnH is 1:(3-10); the molar ratio of P4 to free radical initiator is 1:(0.05-0.1); and the molar ratio of P4 to acid is 1:(20-40).

[0010] In some embodiments, the reaction temperature is 25-40° C., and the reaction time is 1-2 h.

[0011] In some embodiments, after the reaction is completed, 0.5 mL of the reaction solution is placed in a nuclear magnetic resonance tube. 31 P NMR spectrum was used to analyze and calculate the nuclear magnetic yield, with Ph3PO as the internal standard.

[0012] In some embodiments, a method for preparing phosphine comprises the following steps: P4, Bu3SnH, initiator A , acetonitrile are added to a flat-bottomed test tube with a stopper, the test tube is sealed, wrapped with aluminum foil to avoid light, heated to 35°C and stirred for 1.5 hours; then a 1,4-dioxane solution of HCl is added to the reaction mixture, and the stirring reaction is continued at room temperature for 30 minutes to obtain phosphine.

[0013] The present invention has achieved the following beneficial effects: Initiator A screened by the present invention: and initiator B: It can efficiently catalyze the reaction of P4 and Bu3SnH to generate the corresponding intermediate compound, with low reaction temperature, short reaction time, good safety, and high phosphine yield, which is very suitable for industrial production. DETAILED DESCRIPTION

[0014] The endpoints and any values of the ranges described herein are not limited to the precise ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be considered to be specifically disclosed herein.

[0015] The present invention does not limit the sources of the raw materials used. Unless otherwise specified, the raw materials used in the present invention are all common commercially available products in the technical field. Among them, the following free radical initiators are used in the specific embodiment: Initiator A: ; Initiator B: ; Initiator AIBN: ; Initiator TEMPO: .

[0016] The reaction scheme of the present invention is: Example 1 P4 (0.01 mmol), Bu3SnH (0.06 mmol), initiator A: (0.001 mmol) and acetonitrile (2 mL) were added to a flat-bottomed stoppered test tube (10 mL). The test tube was sealed and wrapped with aluminum foil to protect from light. The reaction mixture was stirred at room temperature for 1 h. HCl (0.3 mmol, 2.0 M, dissolved in 1,4-dioxane) was then added to the reaction mixture. The reaction mixture was stirred at room temperature for 30 min to obtain a colorless solution. 0.5 mL of the reaction solution was placed in an NMR tube and quenched with water. 31 The yield of the product was 90.5% (using Ph3PO as internal standard) by P NMR spectrum analysis.

[0017] 31 P NMR(162MHz, CD3CN, δ) -241.0 (q, 1 J P–H = 188 Hz) . Example 2 P4 (0.01 mmol), Bu3SnH (0.06 mmol), initiator B: (0.001 mmol) and acetonitrile (2 mL) were added to a flat-bottomed stoppered test tube (10 mL). The test tube was sealed and wrapped with aluminum foil to protect from light. The reaction mixture was stirred at room temperature for 1 h. HCl (0.3 mmol, 2.0 M, dissolved in 1,4-dioxane) was then added to the reaction mixture. The reaction mixture was stirred at room temperature for 30 min to obtain a colorless solution. 0.5 mL of the reaction solution was placed in an NMR tube and quenched with water. 31 The yield was 88.2% by P NMR spectrum analysis (with Ph3PO as internal standard).

[0018] 31 P NMR(162MHz, CD3CN, δ)-241.0 (q, 1 J P–H = 188 Hz) . Example 3 P4 (0.01 mmol), Bu3SnH (0.05 mmol), initiator A (0.001 mmol) and acetonitrile (2 mL) were added to a flat-bottomed stoppered test tube (10 mL). The test tube was sealed and wrapped with aluminum foil to protect from light. The mixture was heated to 35°C and stirred for 1.5 h. HCl (0.3 mmol, 2.0 M, dissolved in 1,4-dioxane) was then added to the reaction mixture and stirred for 30 min at room temperature to obtain a colorless solution. 0.5 mL of the reaction solution was placed in an NMR tube and quenched with water. 31 The NMR spectrum was analyzed and the NMR yield was 92.3% (with Ph3PO as internal standard).

[0019] 31 P NMR(162MHz, CD3CN, δ) -241.0 (q, 1 J P–H = 188 Hz) . Example 4 P4 (0.01 mmol), Bu3SnH (0.05 mmol), initiator B: (0.001 mmol) and acetonitrile (2 mL) were added to a flat-bottomed stoppered test tube (10 mL). The test tube was sealed and wrapped with aluminum foil to protect from light. The mixture was heated to 35°C and stirred for 1.5 h. HCl (0.3 mmol, 2.0 M, dissolved in 1,4-dioxane) was then added to the reaction mixture and stirred for 30 min at room temperature to obtain a colorless solution. 0.5 mL of the reaction solution was placed in an NMR tube and quenched with water. 31 The NMR spectrum was analyzed and the NMR yield was 89.6% (with Ph3PO as internal standard).

[0020] 31 P NMR(162MHz, CD3CN, δ) -241.0 (q, 1 J P–H = 188 Hz) . Example 5 P4 (0.01 mmol), Bu3SnH (0.06 mmol), initiator A: (0.001 mmol) and ether (2 mL) were added to a flat-bottomed stoppered test tube (10 mL). The test tube was sealed and wrapped with aluminum foil to protect from light. The reaction mixture was stirred at room temperature for 1 hour. HCl (0.3 mmol, 2.0 M, dissolved in 1,4-dioxane) was then added to the reaction mixture. The reaction mixture was stirred at room temperature for 30 minutes to obtain a colorless solution. 0.5 mL of the reaction solution was placed in an NMR tube and quenched with water. 31 The yield was 87.3% by P NMR spectrum analysis (with Ph3PO as internal standard).

[0021] 31 P NMR(162MHz, CD3CN, δ) -241.0 (q, 1 J P–H = 188 Hz) . Example 6 P4 (0.01 mmol), Bu3SnH (0.06 mmol), initiator B: (0.001 mmol) and ethyl acetate (2 mL) were added to a flat-bottomed stoppered test tube (10 mL). The test tube was sealed and wrapped with aluminum foil to protect from light. The reaction mixture was stirred at room temperature for 1 hour. HCl (0.3 mmol, 2.0 M, dissolved in 1,4-dioxane) was then added to the reaction mixture. The reaction mixture was stirred at room temperature for 30 minutes to obtain a colorless solution. 0.5 mL of the reaction solution was placed in an NMR tube and quenched with water. 31 The NMR spectrum was analyzed and the NMR yield was 85.9% (with Ph3PO as internal standard).

[0022] 31 P NMR(162MHz, CD3CN, δ) -241.0 (q, 1 J P–H = 188 Hz) . Comparative Example 1 On the basis of Example 1, initiator A: Replaced with initiator AIBN: , other operations and conditions are the same as in Example 1, specifically as follows: P4 (0.01 mmol), Bu3SnH (0.06 mmol), initiator AIBN: (0.001 mmol) and acetonitrile (2 mL) were added to a flat-bottomed stoppered test tube (10 mL). The test tube was sealed and wrapped with aluminum foil to protect from light. The reaction mixture was stirred at room temperature for 1 h. HCl (0.3 mmol, 2.0 M, dissolved in 1,4-dioxane) was then added to the reaction mixture. The reaction mixture was stirred at room temperature for 30 min to obtain a colorless solution. 0.5 mL of the reaction solution was placed in an NMR tube and quenched with water. 31 The yield was 63.6% by P NMR spectrum analysis (with Ph3PO as internal standard).

[0023] 31 P NMR(162MHz, CD3CN, δ) -241.0 (q, 1 J P–H = 188 Hz) . Example 2 On the basis of Example 1, initiator A: The initiator was replaced with TEMPO, and the other operations and conditions were the same as in Example 1, as follows: P4 (0.01 mmol), Bu3SnH (0.06 mmol), initiator TEMPO (0.001 mmol), and acetonitrile (2 mL) were added to a flat-bottomed stoppered test tube (10 mL). The test tube was sealed and wrapped with aluminum foil to protect from light. The reaction mixture was stirred at room temperature for 1 h. HCl (0.3 mmol, 2.0 M, dissolved in 1,4-dioxane) was then added to the reaction mixture. The reaction mixture was stirred at room temperature for 30 min to obtain a colorless solution. 0.5 mL of the reaction solution was placed in an NMR tube and quenched with water. 31 The yield was 22.1% by P NMR spectrum analysis (with Ph3PO as internal standard).

[0024] 31 P NMR(162MHz, CD3CN, δ) -241.0 (q, 1 J P–H = 188 Hz) . The above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A method for preparing phosphine, comprising the following steps: P4, Bu3SnH, a free radical initiator, and an organic solvent are added to a stoppered test tube, which is sealed and wrapped with aluminum foil to protect from light. The reaction mixture is stirred for a period of time. Acid is then added to the reaction mixture to obtain phosphine. The reaction scheme is as follows: ； Wherein, the structure of the free radical initiator is: or .

2. The preparation method according to claim 1, characterized in that The reaction solvent is selected from benzene, toluene, 1,4-dioxane, dimethyl sulfoxide, ethanol, methanol, tert-butanol, isopropanol, dichloromethane, chloroform, dimethyl adipate, ethyl acetate, petroleum ether, ether, tetrahydrofuran, acetone, N,N - one or more of dimethylformamide, acetonitrile, cyclohexane, and n-hexane.

3. The preparation method according to claim 2, characterized in that The reaction solvent is selected from one or more of 1,4-dioxane, ethyl acetate, acetonitrile, diethyl ether and n-hexane.

4. The preparation method according to claim 1, characterized in that The acid is an inorganic acid or an organic acid.

5. The preparation method according to claim 4, characterized in that The acid is HCl, HBr, HF, sulfuric acid, nitric acid, formic acid or acetic acid.

6. The preparation method according to claim 1, characterized in that The molar ratio of P4 to Bu3SnH is 1:(3-10); the molar ratio of P4 to free radical initiator is 1:(0.05-0.1); and the molar ratio of P4 to acid is 1:(20-40).

7. The preparation method according to claim 1, characterized in that The reaction temperature is 25~40℃ and the reaction time is 1~2h.

8. The preparation method according to claim 1, characterized in that After the reaction was completed, 0.5 mL of the reaction solution was placed into a nuclear magnetic resonance tube. 31 P NMR spectrum was used to analyze and calculate the nuclear magnetic yield, with Ph3PO as the internal standard.

9. The preparation method according to claim 2, characterized in that The following steps are included; P4, Bu3SnH, initiator A , acetonitrile are added to a flat-bottomed test tube with a stopper, the test tube is sealed, wrapped with aluminum foil to avoid light, heated to 35°C and stirred for 1.5 hours; then a 1,4-dioxane solution of HCl is added to the reaction mixture, and the stirring reaction is continued at room temperature for 30 minutes to obtain phosphine.

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