Post-treatment method for preparing triphenylphosphine by trichlorosilane reduction method

Abstract

The invention discloses a post-treatment method for preparing triphenylphosphine by a trichlorosilane reduction method. The post-treatment method comprises the following steps: dropwise adding an aqueous solution of an ethylene glycol-zinc additive into a reduced concentrated solution containing triphenylphosphine, and carrying out hydrolysis post-treatment. The method solves the problem of triphenylphosphine loss caused by coating of a post-treatment hydrolysis byproduct silicon oxide on the product triphenylphosphine, and the yield of the triphenylphosphine reaches 99.8% or above. The method avoids the defect that in the prior art, a large amount of solvent is used for washing and desorbing triphenylphosphine, the technological process is simple, and the process is safe and controllable.

Description

Technical Field

[0001] The invention relates to the technical field of organic chemical industry, and in particular to a post-treatment process for industrial production of triphenylphosphine. Background Art

[0002] Triphenylphosphine is widely used in many fields such as medicine, pesticides, dyes, fragrances, photosensitive chemicals, polymer catalysts, etc. With the advancement of the organic synthesis industry, the application scenarios of triphenylphosphine are gradually increasing.

[0003] Some domestic manufacturers use the Grignard process with magnesium metal, chlorobenzene and phosphorus trichloride to produce triphenylphosphine. The Grignard process has complicated production process conditions, high control requirements and low product yield.

[0004] Some manufacturers also use the sodium metal method, using chlorobenzene and sodium metal as raw materials to react to form phenyl sodium, which is then reacted with phosphorus trichloride to form triphenylphosphine. This method has great safety risks and is highly dangerous.

[0005] At present, the process of producing triphenylphosphine using trichlorosilane reduction method is on the rise. The triphenylphosphine oxide reduction method is a synthesis method based on triphenylphosphine regeneration technology, which has extremely high industrial application value and good economic benefits.

[0006] Patent CN202311614497.1 discloses a method for recovering triphenylphosphine, which includes reducing TPPO with trichlorosilane to obtain TPP material, and then hydrolyzing the TPP material with an aqueous solution of an inorganic base to obtain an organic phase and an alkaline aqueous phase, and purifying the organic phase to obtain a TPP product. This method requires the use of alkaline solution to dissolve the by-product silicon oxide compound, and the post-treatment releases heat violently, which requires high control and high risk for industrial production. At the same time, the alkaline wastewater produced is not environmentally friendly.

[0007] Patent CN201910593619.0 discloses a method for producing triphenylphosphine by reduction. This method also uses trichlorosilane to reduce TPPO to obtain TPP material. After removing excess trichlorosilane, it is added dropwise into pure water for hydrolysis post-treatment. The post-treatment reaction is violent, and the by-product silicon dioxide is instantly produced and agglomerated. The agglomerated silicon dioxide will cover a large amount of the product TPP, resulting in a low product yield.

[0008] The byproduct of the reduction process to produce triphenylphosphine is a chlorosilicon compound, which needs to be hydrolyzed and quenched. Usually, the post-treatment is directly hydrolyzed and quenched with water or alkali solution. The purified water hydrolysis post-treatment produces silicon dioxide and silica gel, which will cover a large amount of products and cause product loss. The alkali solution post-treatment is highly exothermic, which requires high control requirements for industrial production and is relatively risky.

[0009] Patent CN201210587486.4 increases the number of negative charges in the double layer of silica sol by introducing divalent metal ions into the colloid, thereby reducing the probability of silica sol molecular aggregation and preparing a silica sol with good stability in a wide pH range.

[0010] Therefore, it is an urgent research topic to develop a post-treatment method suitable for the preparation of triphenylphosphine by trichlorosilane reduction method, reduce the post-treatment hydrolysis reaction rate, avoid the coating of the product triphenylphosphine by the agglomeration of hydrolyzed silicon oxide compounds, and improve the yield of triphenylphosphine. Summary of the invention

[0011] The purpose of the present invention is to propose a post-treatment method for preparing triphenylphosphine by trichlorosilane reduction method. By adding ethylene glycol-zinc auxiliary agent during post-treatment, the problem of coating the product triphenylphosphine with silicon oxide compound produced by post-treatment hydrolysis is solved, the yield of triphenylphosphine reaches more than 99.8%, the process flow is simple, and the process is safe and controllable.

[0012] In order to achieve the above invention object, the technical solution of the present invention is as follows:

[0013] A post-treatment method for preparing triphenylphosphine by trichlorosilane reduction method comprises the following steps: dripping an aqueous solution of ethylene glycol-zinc auxiliary agent into a reduction concentrated solution containing triphenylphosphine for hydrolysis post-treatment.

[0014] The reducing concentrated solution of the present invention comprises the following components in percentage by mass: 55% to 65% toluene, 25% to 35% triphenylphosphine, 9.5% to 19.5% silicon dioxide, and 0.01% to 0.1% triphenylphosphine oxide.

[0015] In some preferred embodiments of the present invention, the temperature of the dropping process is controlled at 50-90°C.

[0016] In some preferred embodiments of the present invention, after the hydrolysis post-treatment, the organic phase is filtered and separated, and the solid product triphenylphosphine is obtained after the organic phase is delightened.

[0017] In some preferred embodiments of the present invention, the aqueous solution of the ethylene glycol-zinc adjuvant of the present invention is a composition of ethylene glycol, zinc chloride and water.

[0018] In some preferred embodiments of the present invention, the ethylene glycol-zinc adjuvant of the present invention is a composition of ethylene glycol and zinc chloride, and the mass ratio of ethylene glycol to zinc chloride is 1:(0.1-0.5), preferably 1:(0.2-0.3).

[0019] In some preferred embodiments of the present invention, the mass ratio of the ethylene glycol-zinc adjuvant, water and reduced concentrated solution of the present invention is (0.01-0.05):(0.5-0.9):1, preferably (0.02-0.03):(0.6-0.7):1.

[0020] In the prior art, silicon dioxide is treated by directly adding water for hydrolysis and quenching (see the direct hydrolysis mechanism below). However, silicon dioxide is highly active and reacts violently with water, resulting in the instantaneous precipitation and aggregation of a large number of hydrolysis products, silicon oxide compounds, and the aggregates cover a large amount of product triphenylphosphine oxide, resulting in a loss of product yield.

[0021] Direct hydrolysis mechanism:

[0022]

[0023] The ethylene glycol in the ethylene glycol-zinc additive of the present invention reacts with silicon dichloride before water, which can inhibit the hydrolysis rate of silicon dichloride. The hydrolysis product silicon oxide compound is slowly and evenly precipitated at a low hydrolysis rate, eliminating the side effect of silicon oxide compound agglomeration and coating products. The ethylene glycol catalytic hydrolysis mechanism is shown in the following formula:

[0024] Mechanism of catalytic hydrolysis of ethylene glycol:

[0025]

[0026] At the same time, the zinc ions in the additive can inhibit the gelation of hydrolyzed silicon oxide compounds. Since the silica particles are charged, the silica sol has good stability under suitable conditions. Zinc ions, as a silica sol stabilizer, can weaken the aggregation of silica colloid solution into silica gel. The reduction of gel further weakens the coating of triphenylphosphine and improves the yield of triphenylphosphine.

[0027] The positive effects of the present invention are:

[0028] (1) The problem of the coating loss of the product triphenylphosphine caused by the hydrolysis of the by-product silicon oxide compound during the post-treatment of preparing triphenylphosphine by the trichlorosilane reduction method is solved, and the triphenylphosphine yield reaches more than 99.8%;

[0029] (2) Adding a small amount of additives to solve the problem of silicon oxide compounds coating the product triphenylphosphine oxide, compared with the traditional method of using solvent heating and washing to recover the coated product, greatly reducing the amount of solvent and energy consumption;

[0030] (3) The process is simple, which reduces working hours and simplifies post-processing steps. The reaction conditions are mild, and the reaction process is safe and controllable, which has industrial application value. DETAILED DESCRIPTION

[0031] In order to better understand the technical solution of the present invention, the content of the present invention is further described below in conjunction with the embodiments, but the content of the present invention is not limited to the following embodiments.

[0032] The following describes some of the raw materials used or may be used in the embodiments:

[0033] Trichlorosilane: TCI (Shanghai) Chemical Industry Development Co., Ltd.

[0034] Toluene, xylene, chlorobenzene: Shanghai Titan Technology Co., Ltd.

[0035] Triphenylphosphine oxide, zinc chloride, ethylene glycol: Sigma-Aldrich (Shanghai) Trading Co., Ltd.

[0036] Analytical instrument: Agilent 1260II high performance liquid chromatograph

[0037] Chromatographic column: ZORBAX SB-Phenyl (4.6um×250mm); injection volume: 5.0ul;

[0038] Column temperature: 40°C; flow rate: 1 mL / min; detector: ultraviolet detector (UV);

[0039] Mobile phase: methanol / pure water. See Table 1 for the test method.

[0040] Table 1 Liquid phase test method

[0041]

[0042]

[0043] Example 1

[0044] Weigh 30.00g of triphenylphosphine oxide and 75.21g of toluene into a flask, stir and heat to 70°C, add 36.51g of trichlorosilane dropwise to the above solution, heat to 100°C and stir to react for 5 hours after the addition is complete, and concentrate under reduced pressure to remove trichlorosilane to obtain 90.56g of reduced concentrated solution, the concentrate composition: 55.091% toluene, 31.212% triphenylphosphine, 0.017% triphenylphosphine oxide, 13.680% dichlorosilane.

[0045] Take 0.82g of zinc chloride and 0.08g of ethylene glycol, add 45.28g of purified water, stir and dissolve to obtain an aqueous solution. Slowly drop the aqueous solution into the reduced concentrated solution, control the temperature at 50-90°C during the dropwise addition, continue stirring for 10 minutes after the dropwise addition is completed, filter to remove insoluble matter, separate the filtrate to obtain an oil phase, wash the oil phase with 30.05g of purified water, remove the solvent from the oil phase after washing, and obtain 28.24g of triphenylphosphine product, with a yield of 99.86%.

[0046] Example 2

[0047] Weigh 31.05g of triphenylphosphine oxide and 75.22g of toluene into a flask, stir and heat to 70°C, add 38.11g of trichlorosilane dropwise to the above solution, heat to 100°C and stir to react for 5 hours after the addition is complete, and concentrate under reduced pressure to remove trichlorosilane to obtain 110.60g of reduced concentrated solution, the concentrate composition: 61.942% toluene, 26.450% triphenylphosphine, 0.017% triphenylphosphine oxide, 11.591% dichlorosilane.

[0048] Take 1.84g of zinc chloride and 0.37g of ethylene glycol, add 66.36g of purified water, stir and dissolve to obtain an aqueous solution. Slowly drop the aqueous solution into the reduced concentrated solution, control the temperature at 50-90°C during the dropwise addition, continue stirring for 10min after the dropwise addition is completed, filter to remove insoluble matter, separate the filtrate to obtain an oil phase, wash the oil phase with 30.02g of purified water, remove the solvent from the oil phase after washing, and obtain 29.24g of triphenylphosphine product, with a yield of 99.90%.

[0049] Example 3

[0050] Weigh 30.29g of triphenylphosphine oxide and 72.15g of toluene into a flask, stir and heat to 70°C, add 36.62g of trichlorosilane dropwise to the above solution, heat to 100°C and stir to react for 5 hours after the addition is complete, and concentrate under reduced pressure to remove trichlorosilane to obtain 100.56g of reduced concentrated solution, the concentrate composition: 59.170% toluene, 28.371% triphenylphosphine, 0.019% triphenylphosphine oxide, 12.440% dichlorosilane.

[0051] Take 2.32g of zinc chloride and 0.70g of ethylene glycol, add 70.39g of purified water, stir and dissolve to obtain an aqueous solution. Slowly drop the aqueous solution into the reduced concentrated solution, control the temperature at 50-90°C during the dropwise addition, continue stirring for 10min after the dropwise addition is completed, filter to remove insoluble matter, separate the filtrate to obtain an oil phase, wash the oil phase with 30.05g of purified water, remove the solvent from the oil phase after washing, and obtain 28.52g of triphenylphosphine product, with a yield of 99.89%.

[0052] Example 4

[0053] Weigh 30.50g of triphenylphosphine oxide and 75.16g of toluene into a flask, stir and heat to 70°C, add 37.8g of trichlorosilane dropwise to the above solution, heat to 100°C and stir to react for 5 hours after the addition is complete, and concentrate under reduced pressure to remove trichlorosilane to obtain 98.81g of reduced concentrated solution, the concentrate composition: 58.161% toluene, 29.073% triphenylphosphine, 0.015% triphenylphosphine oxide, 12.751% dichlorosilane.

[0054] Take 2.82g of zinc chloride and 1.13g of ethylene glycol, add 79.05g of purified water, stir and dissolve to obtain an aqueous solution. Slowly drop the aqueous solution into the reduced concentrated solution, control the temperature at 50-90°C during the dropwise addition, continue stirring for 10min after the dropwise addition is completed, filter to remove insoluble matter, separate the filtrate to obtain an oil phase, wash the oil phase with 30.02g of purified water, remove the solvent from the oil phase after washing, and obtain 28.70g of triphenylphosphine product, with a yield of 99.85%.

[0055] Example 5

[0056] Weigh 30.02g of triphenylphosphine oxide and 75.36g of toluene into a flask, stir and heat to 70°C, add 36.42g of trichlorosilane dropwise to the above solution, heat to 100°C and stir to react for 5 hours after the addition is complete, and concentrate under reduced pressure to remove trichlorosilane to obtain 112.20g of reduced concentrated solution, the concentrate composition: toluene 63.729%, triphenylphosphine 25.201%, triphenylphosphine oxide 0.021%, dichlorosilane 11.049%.

[0057] Take 3.74g of zinc chloride and 1.87g of ethylene glycol, add 100.98g of purified water, stir and dissolve to obtain an aqueous solution. Slowly drop the aqueous solution into the reduced concentrated solution, control the temperature at 50-90°C during the dropwise addition, continue stirring for 10min after the dropwise addition is completed, filter to remove insoluble matter, separate the filtrate to obtain an oil phase, wash the oil phase with 30.05g of purified water, remove the solvent from the oil phase after washing, and obtain 28.26g of triphenylphosphine product, with a yield of 99.87%.

[0058] Comparative Example 1

[0059] Weigh 30.06g of triphenylphosphine oxide and 75.53g of toluene into a flask, stir and heat to 70°C, add 36.51g of trichlorosilane dropwise to the above solution, heat to 100°C and stir to react for 5 hours after the addition is complete, and concentrate under reduced pressure to remove trichlorosilane to obtain 110.5g of reduced concentrated solution, the concentrate composition: toluene 63.121%, triphenylphosphine 25.629%, triphenylphosphine oxide 0.0190%, dichlorosilane 11.231%.

[0060] 66.35 g of purified water was slowly added dropwise to the reduced concentrated solution, and the temperature was controlled at 50-90° C. during the addition process. After the addition was completed, stirring was continued for 10 min. The insoluble matter was removed by filtration, and the filtrate was separated to obtain an oil phase. The oil phase was washed with 30.05 g of purified water. After washing, the oil phase was desolventized to obtain 26.30 g of triphenylphosphine product with a yield of 92.7%.

[0061] Comparative Example 2

[0062] Weigh 30.05g of triphenylphosphine oxide and 75.43g of toluene into a flask, stir and heat to 70°C, add 36.52g of trichlorosilane dropwise to the above solution, heat to 100°C and stir to react for 5 hours after the addition is complete, and concentrate under reduced pressure to remove trichlorosilane to obtain 109.23g of reduced concentrated solution, the concentrate composition: toluene 62.709%, triphenylphosphine 25.921%, triphenylphosphine oxide 0.017%, dichlorosilane 11.353%.

[0063] Take 1.84g of zinc chloride, add 66.36g of purified water, stir and dissolve. Slowly add the aqueous solution dropwise to the reduced concentrate, control the temperature at 50-90°C during the dropwise addition, continue stirring for 10min after the dropwise addition is completed, filter to remove insoluble matter, separate the filtrate to obtain an oil phase, wash the oil phase with 30.01g of purified water, remove the solvent from the oil phase after washing, and obtain 26.56g of triphenylphosphine product, with a yield of 93.76%.

[0064] Comparative Example 3

[0065] Weigh 30.03g of triphenylphosphine oxide and 75.56g of toluene into a flask, stir and heat to 70°C, add 36.52g of trichlorosilane dropwise to the above solution, heat to 100°C and stir to react for 5 hours after the addition is complete, and concentrate under reduced pressure to remove trichlorosilane to obtain 111.12g of reduced concentrated solution, which consists of: 63.371% toluene, 25.459% triphenylphosphine, 0.0120% triphenylphosphine oxide, and 11.158% dichlorosilane.

[0066] Take 0.37g of ethylene glycol, add 66.50g of purified water, stir and mix. Slowly drop the mixed solution into the reduced concentrate, control the temperature at 50-90°C during the dropwise addition, continue stirring for 10min after the dropwise addition is completed, filter to remove insoluble matter, separate the filtrate to obtain an oil phase, wash the oil phase with 30.05g of purified water, remove the solvent from the oil phase after washing, and obtain 27.79g of triphenylphosphine product, with a yield of 98.20%.

[0067] Comparative Example 4

[0068] Weigh 30.06g of triphenylphosphine oxide and 75.26g of toluene into a flask, stir and heat to 70°C, add 36.51g of trichlorosilane dropwise to the above solution, heat to 100°C and stir to react for 5 hours after the addition is complete, and concentrate under reduced pressure to remove trichlorosilane to obtain 108.98g of reduced concentrated solution, the concentrate composition: toluene 62.610%, triphenylphosphine 25.989%, triphenylphosphine oxide 0.0120%, dichlorosilane 11.389%.

[0069] Take 1.84g of zinc chloride and 0.37g of 1,3-propylene glycol, add 66.38g of purified water, and stir to dissolve. Slowly drop the aqueous solution into the reduced concentrated solution, control the temperature at 50-90°C during the dropwise addition, continue stirring for 10 minutes after the dropwise addition is completed, filter to remove insoluble matter, separate the filtrate to obtain an oil phase, wash the oil phase with 30.04g of purified water, remove the solvent from the oil phase after washing, and obtain 26.58g of triphenylphosphine product, with a yield of 93.80%.

[0070] Comparative Example 5

[0071] Weigh 30.02g of triphenylphosphine oxide and 75.33g of toluene into a flask, stir and heat to 70°C, add 36.52g of trichlorosilane dropwise to the above solution, heat to 100°C and stir to react for 5 hours after the addition is complete, and concentrate under reduced pressure to remove trichlorosilane to obtain 110.23g of reduced concentrated solution, the concentrate composition: toluene 63.079%, triphenylphosphine 25.651%, triphenylphosphine oxide 0.022%, dichlorosilane 11.248%.

[0072] Take 1.84g of magnesium chloride and 0.37g of ethylene glycol, add 66.54g of purified water, stir and dissolve. Slowly drop the aqueous solution into the reduced concentrate, control the temperature at 50-90°C during the dropwise addition, continue stirring for 10min after the dropwise addition is completed, filter to remove insoluble matter, separate the filtrate to obtain an oil phase, wash the oil phase with 30.05g of purified water, remove the solvent from the oil phase after washing, and obtain 28.00g of triphenylphosphine product, with a yield of 98.95%.

Claims

1. A post-treatment method for preparing triphenylphosphine by trichlorosilane reduction method, comprising the following steps: An aqueous solution of ethylene glycol-zinc auxiliary agent is added dropwise to the reduced concentrated solution containing triphenylphosphine for post-hydrolysis treatment.

2. The method according to claim 1, characterized in that The reduced concentrated solution comprises the following components: Toluene 55wt%-65wt%, triphenylphosphine 25wt%-35wt%, silicon dioxide 9.5wt%-19.5wt%, triphenylphosphine oxide 0.01wt%-0.1wt%.

3. The method according to claim 1 or 2, characterized in that: The temperature of the dropping process is controlled at 50-90°C.

4. The method according to any one of claims 1 to 3, characterized in that: After the hydrolysis treatment, the organic phase is filtered and separated, and the solid product triphenylphosphine is obtained after the organic phase is delightened.

5. The method according to any one of claims 1 to 4, characterized in that: The aqueous solution of ethylene glycol-zinc additive is a composition of ethylene glycol, zinc chloride and water.

6. The method according to claim 5, characterized in that The mass ratio of ethylene glycol to zinc chloride is 1:(0.1~0.5).

7. The method according to claim 5, characterized in that The mass ratio of ethylene glycol to zinc chloride is 1:(0.2~0.3).

8. The method according to claim 5, characterized in that The mass ratio of ethylene glycol-zinc auxiliary agent, water and reducing concentrated solution is (0.01-0.05):(0.5-0.9):

1.

9. The method according to claim 6, characterized in that The mass ratio of ethylene glycol-zinc additive, water and reducing concentrated solution is (0.02-0.03):(0.6-0.7):1.

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