A method for preparing a phosphorane

Abstract

The application belongs to the field of organic phosphorus chemistry and phosphorus chemical industry, and particularly relates to a preparation method of phosphine. The method comprises 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 aluminum foil to avoid light, and stirring the test tube for a period of time; and then adding an acid into the reaction mixture to obtain phosphine. The application has mild reaction conditions, good safety and is suitable for industrial production.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of organic phosphorus chemistry and phosphorus chemical industry, and particularly relates to a preparation method of phosphine. BACKGROUND

[0002] Phosphine (also known as phosphine, PH3) is a linear structure of phosphorus hydride, which is a colorless and highly toxic gas at room temperature, condenses into a liquid at -88℃, and solidifies at -133.8℃. Due to the chemical activity of P-H bond, phosphine can add to unsaturated groups and coordinate with Lewis acids and metal ions. PH3 and its derivatives act as ligands and transition metals and their salts through P-M σ bond and d(M)-d(P) feedback π bond, forming a series of important coordination compounds. Most of these coordination compounds have strong catalytic activity and are widely used as catalysts for olefin hydrogenation, hydrosilylation, carbonylation and other reactions. In addition, high-purity phosphine can be used as an important electronic gas adjusting material in solar energy and semiconductor materials; a small amount of phosphine will be used as a fumigant in grain storage. At the same time, phosphine derivatives are also widely used in bactericides, biological reducing agents, mixed metal separation agents, flame retardants and quantum dots, and other fine chemicals. At present, the main methods for preparing phosphine in industry are:

[0003] 1) By-product method. A large amount of PH3 is produced as a by-product when sodium hypophosphite is produced by reaction of yellow phosphorus and alkali. Patent CN201310289015.X and CN201210522061.5 disclose a preparation method of phosphine, which is to generate phosphine, hypophosphite and phosphite by reaction of yellow phosphorus and alkali, to obtain a mixture of hypophosphorous acid and phosphorous acid by treating the hypophosphite and phosphite with inorganic acid, and to generate phosphine and by-product phosphoric acid by pyrolysis of the mixed acid. The equation is as follows: ;

[0004] However, NaH2PO2 in the above method will further react under alkaline conditions to generate H2 and Na3PO4, resulting in PH3 containing a certain amount of H2. In addition, the highest yield of phosphine generated by this method is only 25%.

[0005] 2) Pyrolysis. Patent CN201310289544.X discloses a method for producing PH3 by pyrolysis of phosphorous acid, which utilizes platinum-carbon catalyst to pyrolyze phosphorous acid at 150-200℃, thereby obtaining high-purity PH3. CN201310290020.2 and CN201210521890.1 disclose a method for simultaneously preparing PH3 and sodium trimetaphosphate. A mixture of sodium trivalent phosphate and sodium pentavalent phosphate salt with a certain composition is heated at 200-400℃ under nitrogen protection to undergo disproportionation and condensation reactions, thereby obtaining relatively pure PH3 and sodium trimetaphosphate. However, the above method needs to be carried out under high-temperature conditions, which is relatively harsh.

[0006] 3) Other methods. CN202210379814.5 discloses a preparation method of phosphine / deuterated phosphine and derivatives thereof. The method is to efficiently prepare phosphine or deuterated phosphine by using white phosphorus and a compound or mixture containing proton (H + ) or deuterated proton (D + ) as the reaction raw material. However, the above method has a long reaction time and low yield, which is not suitable for industrial production.

[0007] In view of the problems of low yield, harsh reaction conditions, and unsuitability for industrial production in the prior art, there is an urgent need to develop a new preparation method of phosphine. SUMMARY

[0008] The purpose of the present application is to provide a preparation method of phosphine to solve the problems of low yield, harsh reaction conditions, and unsuitability for industrial production in the prior art. To solve the above technical problems, the present application provides the following technical solutions:

[0009] A preparation method of phosphine, comprising the following steps:

[0010] P4, Bu3SnH, a free radical initiator, and an organic solvent are added to a test tube with a plug, the test tube is sealed, wrapped with aluminum foil to avoid light, and stirred for a period of time; then an acid is added to the reaction mixture to obtain phosphine, and the reaction route is as follows: ;

[0011] The structure of the free radical initiator is: or .

[0012] In some embodiments, the organic solvent is selected from one or more of benzene, toluene, 1,4-dioxane, dimethyl sulfoxide, ethanol, methanol, tert-butanol, isopropanol, dichloromethane, trichloromethane, dimethyl adipate, ethyl acetate, petroleum ether, diethyl ether, tetrahydrofuran, acetone, N,N-dimethylformamide, acetonitrile, cyclohexane, and n-hexane.

[0013] In some embodiments, the organic solvent is selected from one or more of 1,4-dioxane, ethyl acetate, acetonitrile, diethyl ether and n-hexane.

[0014] In some embodiments, the acid is an inorganic acid or an organic acid.

[0015] In some embodiments, the acid is HCl, HBr, HF, sulfuric acid, nitric acid, formic acid or acetic acid.

[0016] In some embodiments, the acid is preferably a 1,4-dioxane solution of HCl.

[0017] In some embodiments, the molar ratio of P4 to Bu3SnH is 1:(3-10); the molar ratio of P4 to radical initiator is 1:(0.05-0.1); and the molar ratio of P4 to acid is 1:(20-40).

[0018] In some embodiments, the reaction temperature is 25-40℃ and the reaction time is 1-2h.

[0019] In some embodiments, after the reaction is completed, 0.5mL of the reaction solution is taken and loaded into an NMR tube, and 0.5mL of CDCl3 is added as an internal standard.

[0020] 31 The NMR spectrum is analyzed and the NMR yield is calculated, with Ph3PO as the internal standard.

[0021] In some embodiments, a method for preparing a phosphorane comprises the following steps:

[0022] P4, Bu3SnH, initiator A , acetonitrile are added to a flat-bottomed test tube with a plug, the test tube is sealed, wrapped with aluminum foil to avoid light, heated to 35℃ and stirred for 1.5h; then 1,4-dioxane solution of HCl is added to the reaction mixture, and the reaction is continued at room temperature for 30min to obtain the phosphorane.

[0023] The present application has the following beneficial effects:

[0024] The initiator A and initiator B screened in the present application: and initiator B: can efficiently catalyze the reaction of P4 and Bu3SnH to generate the corresponding intermediate compounds, with low reaction temperature, short reaction time, good safety and high phosphorane yield, which is very suitable for industrial production. DETAILED DESCRIPTION

[0025] The endpoints of the ranges and any values specified in this application are not limited to the precise values stated. The endpoints of the ranges and the values are approximations that are understood to encompass values approximating these.

[0026] The application does not limit the source of raw materials used, and the raw materials used in the application are generally commercially available unless otherwise specified. In the specific embodiments, the following radical initiators are used:

[0027] Initiator A: ;

[0028] Initiator B: ;

[0029] Initiator AIBN: ;

[0030] Initiator TEMPO: .

[0031] The reaction route of the application is:

[0032] Example 1

[0033] P4 (0.01 mmol), Bu3SnH (0.06 mmol), initiator A:

[0034] (0.001 mmol), acetonitrile (2 mL) were added to a flat-bottomed test tube with a stopper (10 mL), the test tube was sealed and wrapped with aluminum foil to avoid light, and stirred at room temperature for 1 h. Then HCl (0.3 mmol, 2.0 M, dissolved in 1,4-dioxane) was added to the reaction mixture, and the stirring was continued at room temperature for 30 min to obtain a colorless solution. 0.5 mL of the reaction solution was taken and loaded into an NMR tube, and 31 The NMR spectrum was analyzed, and the NMR yield was 90.5% (Ph3PO as internal standard).

[0035] 31 PNMR (162 MHz, CD3CN, δ) -241.0 (q, 1 J P-H = 188 Hz). Example 2

[0036] P4 (0.01 mmol), Bu3SnH (0.06 mmol), initiator B:

[0037] 0.001 mmol of acetonitrile (2 mL) was added to a 10 mL flat-bottomed, stoppered test tube. The test tube was sealed and wrapped with aluminum foil to protect it from light. The reaction mixture was stirred at room temperature for 1 h. Then, 0.3 mmol of HCl (2.0 M, soluble in 1,4-dioxane) was added to the reaction mixture, and the mixture was stirred at room temperature for another 30 min to obtain a colorless solution. 0.5 mL of the reaction solution was loaded into an NMR tube and... 31 PNMR spectroscopy analysis was performed, with an NMR yield of 88.2% (using Ph3PO as an internal standard).

[0038] 31 PNMR(162MHz, CD3CN, δ)-241.0 (q, 1 J P-H = 188 Hz). Example 3

[0039] P4 (0.01 mmol), Bu3SnH (0.05 mmol), and initiator A were added. 0.001 mmol of acetonitrile (2 mL) was added to a 10 mL flat-bottomed, stoppered test tube. The test tube was sealed, wrapped with aluminum foil to protect it from light, and heated to 35 °C with stirring for 1.5 h. Then, 0.3 mmol of HCl (2.0 M, soluble in 1,4-dioxane) was added to the reaction mixture, and the mixture was stirred at room temperature for 30 min to obtain a colorless solution. 0.5 mL of the reaction solution was loaded into an NMR tube and... 31 PNMR spectroscopy analysis yielded a yield of 92.3% (using Ph3PO as an internal standard).

[0040] 31 PNMR(162MHz, CD3CN, δ) -241.0 (q, 1 J P-H = 188 Hz). Example 4

[0041] Add P4 (0.01 mmol), Bu3SnH (0.05 mmol), and initiator B:

[0042] 0.001 mmol of acetonitrile (2 mL) was added to a 10 mL flat-bottomed, stoppered test tube. The test tube was sealed, wrapped with aluminum foil to protect it from light, and heated to 35°C with stirring for 1.5 h. Then, HCl (0.3 mmol, 2.0 M, soluble in 1,4-dioxane) was added to the reaction mixture, and the mixture was stirred at room temperature for 30 min to obtain a colorless solution. 0.5 mL of the reaction solution was loaded into an NMR tube and... 31 The NMR spectrum was analyzed, and the NMR yield was 89.6% (with Ph3PO as an internal standard).

[0043] 31 PNMR(162MHz, CD3CN, δ) -241.0 (q, 1 J P-H = 188 Hz). Example 5

[0044] P4 (0.01 mmol), Bu3SnH (0.06 mmol), and initiator A:

[0045] 0.001 mmol of HCl and 2 mL of ether were added to a 10 mL flat-bottomed, stoppered test tube. The test tube was sealed and wrapped with aluminum foil to protect it from light. The mixture was stirred at room temperature for 1 h. Then, 0.3 mmol of HCl (2.0 M, soluble in 1,4-dioxane) was added to the reaction mixture, and the mixture was stirred at room temperature for another 30 min to obtain a colorless solution. 0.5 mL of the reaction solution was loaded into an NMR tube and... 31 PNMR spectroscopy analysis yielded an NMR yield of 87.3% (using Ph3PO as an internal standard).

[0046] 31 PNMR(162MHz, CD3CN, δ) -241.0 (q, 1 J P-H = 188 Hz). Example 6

[0047] P4 (0.01 mmol), Bu3SnH (0.06 mmol), and initiator B were added.

[0048] 0.001 mmol of ethyl acetate (2 mL) was added to a 10 mL flat-bottomed, stoppered test tube. The test tube was sealed and wrapped with aluminum foil to protect it from light. The mixture was stirred at room temperature for 1 h. Then, 0.3 mmol of HCl (2.0 M, soluble in 1,4-dioxane) was added to the reaction mixture, and the mixture was stirred at room temperature for another 30 min to obtain a colorless solution. 0.5 mL of the reaction solution was loaded into an NMR tube and... 31 PNMR spectroscopy analysis yielded an NMR yield of 85.9% (using Ph3PO as an internal standard).

[0049] 31 PNMR(162MHz, CD3CN, δ) -241.0 (q, 1 J P-H = 188 Hz).

[0050] Comparative Example 1

[0051] Based on Example 1, initiator A: Replace with initiator AIBN: Other operations and conditions are the same as in Example 1, as detailed below:

[0052] P4 (0.01 mmol), Bu3SnH (0.06 mmol), and initiator AIBN: 0.001 mmol of acetonitrile (2 mL) was added to a 10 mL flat-bottomed, stoppered test tube. The test tube was sealed and wrapped with aluminum foil to protect it from light. The reaction mixture was stirred at room temperature for 1 h. Then, 0.3 mmol of HCl (2.0 M, soluble in 1,4-dioxane) was added to the reaction mixture, and the reaction was stirred at room temperature for another 30 min to obtain a colorless solution. 0.5 mL of the reaction solution was loaded into an NMR tube and... 31 PNMR spectroscopy analysis yielded a yield of 63.6% (using Ph3PO as an internal standard).

[0053] 31 PNMR(162MHz, CD3CN, δ) -241.0 (q, 1 J P-H = 188 Hz).

[0054] Comparative Example 2

[0055] Based on Example 1, initiator A The initiator is replaced with TEMPO, and other operations and conditions are the same as in Example 1, as follows:

[0056] P4 (0.01 mmol), Bu3SnH (0.06 mmol), initiator TEMPO (0.001 mmol), acetonitrile (2 mL) were added to a flat bottomed test tube (10 mL) with a stopper, the test tube was sealed and wrapped in aluminum foil to protect from light, the reaction was stirred at room temperature for 1 h. Then to the reaction mixture was added HCl (0.3 mmol, 2.0 M in 1,4-dioxane), the reaction was stirred at room temperature for an additional 30 min to give a colorless solution. A 0.5 mL aliquot of the reaction was taken and loaded into an NMR tube and 31 The PNMR spectrum was analyzed and the NMR yield was 22.1% (using Ph3PO as an internal standard).

[0057] 31 PNMR (162 MHz, CD3CN, δ) -241.0 (q, 1 J P-H = 188 Hz).

[0058] The foregoing examples are merely illustrative of the present embodiments and are not intended to limit the scope of the present embodiments. Other variations and modifications can be made to the foregoing examples by those of ordinary skill in the art without departing from the scope of the present embodiments. The above description is intended to be illustrative and not restrictive. Many embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the embodiments should, therefore, be determined not with reference to the above description, but instead with reference to the appended claims, along with their full scope of equivalents.

Claims

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

2. The production method according to claim 1, characterized by, said organic solvent is selected from one or more of benzene, toluene, 1,4-dioxane, dimethyl sulfoxide, ethanol, methanol, tert-butanol, isopropanol, dichloromethane, trichloromethane, dimethyl adipate, ethyl acetate, petroleum ether, diethyl ether, tetrahydrofuran, acetone, N,N-dimethylformamide, acetonitrile, cyclohexane, n-hexane.

3. The production method according to claim 2, characterized by, said organic solvent is selected from one or more of 1,4-dioxane, ethyl acetate, acetonitrile, diethyl ether and n-hexane.

4. The method of claim 1, wherein, said acid is an inorganic acid or an organic acid.

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

6. The method of claim 1, wherein, said molar ratio of P4 to Bu3SnH is 1:(3-10); said molar ratio of P4 to radical initiator is 1:(0.05-0.1); said molar ratio of P4 to acid is 1:(20-40).

7. The preparation method according to claim 1, characterized in that, said reaction temperature is 25-40°C and said reaction time is 1-2h.

8. The method of claim 1, wherein, After the reaction, 0.5 mL of the reaction solution was taken and loaded into an NMR tube, and the NMR spectrum was analyzed and the NMR yield was calculated, with Ph3PO as an internal standard. 31 PNMR spectra were analyzed and NMR yields were calculated with Ph3PO as an internal standard.

9. The preparation method according to claim 2, characterized in that, comprising the steps of: P4, Bu3SnH, initiator A , acetonitrile were added to a flat bottomed tube with a stopper, the tube was sealed and wrapped in aluminium foil to protect from light, and heated to 35°C with stirring for 1.5h; then a solution of HCI in 1,4-dioxane was added to the reaction mixture and stirring continued at room temperature for 30min to give the phosphorane.

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