Method for preparing organic phosphine compound by reducing phosphine-sulfur compound with high selectivity of hydrogen

Abstract

The invention discloses a method for preparing an organic phosphine compound by reducing a phosphine-sulfur compound with high selectivity through hydrogen, and belongs to the field of organic synthesis. The method comprises the following steps: in a solvent-free or organic solvent, taking hydrogen as a reducing agent, and carrying out heating reaction, separation and purification on the phosphine-sulfur compound R1R2R3PS under the action of an additive to obtain the organic phosphine compound R1R2R3P, wherein R1, R2 and R3 are independently selected from aromatic or fat substituents, and at least one of R1, R2 and R3 is selected from aromatic. The hydrogen is used as a reducing agent to replace metal hydride, the method is simple in process and low in cost, and the obtained organic phosphine compound is high in yield and purity, wide in application range and suitable for large-scale production. The whole technological process is safe and pollution-free, and conforms to the concept of green chemical development.

Description

Technical Field

[0001] The present invention relates to the field of organic synthesis, and more particularly to a method for preparing a trivalent organic phosphine compound by reducing a phosphine-sulfur compound with high selectivity using hydrogen. Background Art

[0002] Organophosphine compounds are widely used in fine chemical fields such as catalysis, materials chemistry, biology, and pharmaceuticals. Triphenylphosphine is an important fine chemical intermediate used in the preparation of flame retardants, heat stabilizers, rubber anti-oxidants, antistatic agents, and optoelectronic materials. Furthermore, in organic synthetic chemistry, triphenylphosphine is a key chemical synthesis reagent, widely used in various important chemical reactions such as the Wittig reaction, the Staudinger reaction, the Mitsunobu reaction, and the Appel reaction.

[0003] In addition, triphenylphosphine can also be used as a desulfurization reagent for disulfide (RS-SR) to prepare sulfide compounds (RSR). This method can be used industrially in the preparation process of antibiotic intermediates and produces an equivalent amount of triphenylphosphine sulfide as a byproduct. Triphenylphosphine sulfide has a low application value and is very stable. Therefore, in actual production processes, triphenylphosphine sulfide is treated as waste material and processed in a burning manner, causing environmental pollution and a waste of phosphorus resources, which does not conform to the concept of green chemistry.

[0004] To avoid the waste of phosphorus resources, the reduction of triphenylphosphine sulfide to triphenylphosphine has attracted attention. The reducing agents used include sodium hydride (Jin, Hongyu; Gu, Chengshan; Xiao, Zhihuan; Tan, Qihang; Liu, Long; et al. European Journal of Organic Chemistry, 2023, 26, e202300397), lithium aluminum tetrahydride (Byrne, Peter A. et al. Org. Bio. Chem. 2012, 10, 3531.), Raney nickel (Demchuk, Oleg M. et al. Phosphorus Sulfur Silicon Relat. Elem. 2017, 192, 64.), [Cp2ZrHCl] nTriphenylphosphine sulfide can also be reduced to triphenylphosphine using methods such as Bu3P reflux (Horner, L et al., Chemische Berichete 1958, 91, 1583). However, these methods have the following problems: high cost of reducing agents, poor functional group compatibility, cumbersome product separation steps, safety risks in the production process, and environmental concerns. In addition, triphenylphosphine sulfide can also be reduced to triphenylphosphine using iron powder (Ludwig Maier, HEL VETICA CHIMICA ACT, 1964, 47, 238.), but this method requires a high temperature of 370°C.

[0005] In addition to the above methods, sodium metal can also be used to reduce Ph3PS to triphenylphosphine Ph3P under mild conditions (Zhang, J.-Q. et al. Phosphorus Sulfur Silicon Relat. Elem. 2021, 196, 961-964). However, the generated Ph3P will quickly react with micronized sodium metal (Ye, J. et al. Organometallics 2020, 39, 2682-2694.) to form by-products, and Ph3P cannot be obtained with high selectivity.

[0006] In order to solve the technical problems existing in the above-mentioned synthesis and manufacturing methods, the present invention is committed to developing a safe, controllable, environmentally friendly, low-cost, and highly selective reduced phosphine-sulfur compound R 1 R 2 R 3 Preparation of organic phosphine compounds R by PS 1 R 2 R 3 P's method. Summary of the Invention

[0007] In response to the problems existing in the prior art, the purpose of the present invention is to provide a method for preparing organic phosphine compounds by highly selectively reducing phosphine-sulfur compounds with hydrogen. The method provided by the present invention is simple to operate, has a wide range of applications, is low in cost, is environmentally friendly and safe, and is convenient for industrial scale-up production.

[0008] In order to solve the above problems, the present invention adopts the following technical solutions:

[0009] A method for preparing an organic phosphine compound by highly selective reduction of a phosphine-sulfur compound with hydrogen, wherein hydrogen is used as a reducing agent in a solvent-free or organic solvent atmosphere, and the phosphine-sulfur compound R 1 R 2 R 3 PS is heated, reacted, separated and purified under the action of additives to obtain organic phosphine compound R 1 R 2 R 3 P;

[0010]

[0011] Among them, R 1 、R 2 and R 3 are independently selected from aromatic or aliphatic substituents, R 1 、R 2 and R 3 Can be the same or different, where R 1 、R 2 and R 3 At least one is selected from aryl groups.

[0012] Furthermore, R 1 、R 2 and R 3 Independently selected from C1-C 20 Straight-chain alkyl or branched-chain alkyl, alkenyl, C3-C 20 Cycloalkyl, C7-C 20 Aralkyl, C6-C 20 Aryl and C2-C 20 of a heterocyclic group.

[0013] Furthermore, R 1 、R 2 and R 3 Independently selected from phenyl with C1-C6 long chain alkyl or branched chain alkyl, heterocyclic aromatic hydrocarbon containing N, O, S atoms and C1-C 20 Long chain or branched chain alkyl groups.

[0014] Furthermore, the additive is selected from one or more of potassium tert-butoxide, sodium tert-butoxide, lithium tert-butoxide, potassium hydroxide, sodium hydroxide, potassium carbonate, sodium carbonate, cesium carbonate, potassium chloride, sodium chloride, potassium fluoride, triethylamine, tetramethylethylamine and tricyclohexylamine.

[0015] Furthermore, the additive can be selected from one or any combination of potassium tert-butoxide, sodium tert-butoxide, lithium tert-butoxide and potassium hydroxide.

[0016] Furthermore, the pressure of the hydrogen is 1 to 5.0 MPa. Preferably, the pressure of the hydrogen is 1.0 to 3.0 MPa.

[0017] Furthermore, the additive and the phosphine-sulfur compound R 1 R 2 R 3 The molar ratio of PS is 0.1 to 5:1.

[0018] Furthermore, the additive and the phosphine-sulfur compound R 1 R 2 R 3 The molar ratio of PS is 0.5 to 3:1.

[0019] Furthermore, the phosphine-sulfur compound R 1 R 2 R 3 When PS reacts with hydrogen in an organic solvent, the organic solvent reacts with the phosphine-sulfur compound R 1 R 2 R 3 The weight ratio of PS is 0.5 to 20:1.

[0020] Furthermore, in a hydrogen atmosphere, the phosphine-sulfur compound R 1 R 2 R 3 When PS reacts with hydrogen in an organic solvent, the organic solvent reacts with the phosphine-sulfur compound R 1 R 2 R 3 The weight ratio of PS is 2 to 5:1.

[0021] Furthermore, the organic solvent is selected from one of a non-polar solvent of an alkane or aromatic hydrocarbon and a polar solvent containing a heteroatom.

[0022] Furthermore, the concept and definition of non-polar solvent refers to a class of solvents with low dielectric constants, also known as inert solvents; this type of solvent neither undergoes proton autotransfer reactions nor undergoes solvation with solutes; most of them are saturated hydrocarbons or compounds such as benzene.

[0023] Furthermore, a polar solvent refers to a solvent containing polar groups such as hydroxyl or carbonyl groups, that is, a solvent whose solvent molecules are polar molecules, and the polarity of the molecules is caused by the fact that the centers of gravity of the positive and negative charges in the molecules do not coincide.

[0024] Furthermore, the non-polar solvent is selected from one or more of n-hexane, n-heptane, polyethylene, polypropylene, benzene, toluene, xylene and trimethylbenzene.

[0025] Furthermore, the non-polar compound solvent is one or more of toluene, p-xylene and o-xylene.

[0026] Furthermore, the polar solvent is selected from one or more of tetrahydrofuran, 1,4-dioxane, N,N-dimethylformamide and N,N-dimethylacetamide.

[0027] Furthermore, the reaction temperature is 50-250°C; preferably, the reaction temperature is 100-200°C.

[0028] Furthermore, the phosphine-sulfur compound R 1 R 2 R 3 PS is one or a mixture of any of triphenylphosphine sulfide, tri(o-methylphenyl)phosphine sulfide, phenyldimethylphosphine sulfide, tri(p-methylphenyl)phosphine sulfide, tri(p-methoxyphenyl)phosphine sulfide, diphenyl-2-pyridylphosphine sulfide, diphenylmethylphosphine sulfide and diphenyl-4-(vinyl)phenylphosphine sulfide.

[0029] Further, under the condition of organic solvent, after the reaction is completed, water is added to extract the organic phase, and the organic solvent is removed under reduced pressure to obtain the organic phosphine compound R 1 R 2 R 3 P and unreacted phosphine-sulfur compound R 1 R 2 R 3 PS, and finally obtain the organic phosphine compound R through the purification method of organic synthesis 1 R 2 R 3 P.

[0030] Furthermore, the phosphine-sulfur compound R 1 R 2 R 3 PS and the organic phosphine compound R generated by the reaction 1 R 2 R 3 P is soluble in organic solvents, but the generated metal sulfide salts are insoluble in organic solvents.

[0031] Furthermore, the organic phosphine compound R 1 R 2 R 3 P does not react with additives in the absence of solvent or organic solvent conditions.

[0032] Furthermore, the additives include additives insoluble in organic solvents and additives soluble in organic solvents; the additives insoluble in organic solvents are potassium tert-butoxide, sodium tert-butoxide, lithium tert-butoxide, potassium hydroxide, sodium hydroxide, potassium carbonate, sodium carbonate, cesium carbonate, potassium chloride, sodium chloride or potassium fluoride; the additives soluble in organic solvents are triethylamine, tetramethylethylamine or tricyclohexylamine.

[0033] Furthermore, the phosphine-sulfur compound R 1 R 2 R 3 PS can be a pure substance.

[0034] Furthermore, the phosphine-sulfur compound R 1 R 2 R 3 PS contains impurities, which are one or a mixture of any two or more of organic alcohols and organic ethers, and the impurity content is less than 30%.

[0035] Furthermore, the impurity may also be a phosphine oxide compound R 1 R 2 R 3 PO, organic solvents or inorganic salts.

[0036] Furthermore, the additive does not react with the organic phosphine compound R 1 R 2 R 3 P reaction, impurities do not react with phosphine sulfur compounds R 1 R 2 R 3 PS, organic phosphine compound R 1 R 2 R 3 P reacts with the additive.

[0037] Furthermore, the phosphine-sulfur compound R 1 R 2 R 3 PS reacts with hydrogen in an organic solvent under the action of an additive. After the reaction is completed, the mixed solution is separated, washed with water, and purified to obtain an organic phosphine compound R. 1 R 2 R 3 P.

[0038] Furthermore, in the presence of an organic solvent, after the reaction is completed, water is added to the reaction system and mixed thoroughly to form an organic phase and an aqueous phase, which are then separated and the organic phase is decompressed to remove the organic solvent to obtain an organic phosphine compound R 1 R 2 R 3 P and unreacted phosphine-sulfur compound R 1 R 2 R 3 PS, and finally obtain the organic phosphine compound R through the purification method of organic synthesis 1 R 2 R 3 P.

[0039] Furthermore, in the absence of a solvent, after the reaction is completed, an organic solvent is added to the reaction system, water is added to extract the organic phase, and the organic solvent is removed under reduced pressure to obtain an organic phosphine compound R 1 R 2 R 3 P and unreacted phosphine-sulfur compound R 1 R 2 R 3 PS, and finally obtain the organic phosphine compound R through the purification method of organic synthesis 1 R 2 R 3 P.

[0040] Furthermore, after the reaction is completed, the following separation and purification method can be used to obtain a pure organic phosphine compound R 1 R 2 R 3 P:

[0041] (1) When the additive is insoluble in organic solvent:

[0042] In the presence of an organic solvent, after the reaction is completed, water is added to extract the organic phase, and the organic solvent is removed under reduced pressure to obtain the organic phosphine compound R 1 R 2 R 3 P and any unreacted phosphine-sulfur compound R 1 R 2 R 3 PS, and finally the organic phosphine compound R is purified by organic synthesis methods such as column chromatography, recrystallization or distillation. 1 R 2 R 3 P and any unreacted phosphine-sulfur compound R 1 R 2 R 3 PS can be effectively separated to obtain pure organic phosphine compound R 1 R 2 R 3 P.

[0043] In the absence of solvent, after the reaction is completed, an organic solvent and water are added to the reaction system to extract an organic phase containing the generated organic phosphine compound R 1 R 2 R 3 P and unreacted phosphine sulfide compound R 1 R 2 R 3 PS, remove the organic solvent under reduced pressure to obtain the organic phosphine compound R 1 R 2 R 3 P and any unreacted phosphine-sulfur compound R1 R 2 R 3 PS, and finally the organic phosphine compound R is purified by organic synthesis methods such as column chromatography, recrystallization or distillation. 1 R 2 R 3 P and any unreacted phosphine-sulfur compound R 1 R 2 R 3 PS can be effectively separated to obtain pure organic phosphine compound R 1 R 2 R 3 P.

[0044] (2) When the additive is dissolved in an organic solvent:

[0045] The organic solvent is removed under reduced pressure to obtain the phosphine-sulfur compound R 1 R 2 R 3 PS, organic phosphine compound R 1 R 2 R 3 P and additives, and finally the organic phosphine compound R is purified by organic synthesis methods such as column chromatography, recrystallization or distillation. 1 R 2 R 3 P and any unreacted phosphine-sulfur compound R 1 R 2 R 3 PS can be effectively separated to obtain pure organic phosphine compound R 1 R 2 R 3 P.

[0046] Furthermore, the embodiment of the present invention of highly selective reduction of phosphine-sulfur compounds with hydrogen to prepare organic phosphine compounds is briefly described by taking the preparation of triphenylphosphine from triphenylphosphine sulfide as an example:

[0047] Example under organic solvent conditions: 0.5 mmol of triphenylphosphine sulfide, 1.0 mmol of potassium tert-butoxide, and 3 mL of toluene were placed in a reactor, the gas in the reactor was replaced three times with 2 MPa of hydrogen, the temperature was raised to 150°C under a hydrogen atmosphere, and the reaction was kept warm for 5 hours. After the triphenylphosphine sulfide and hydrogen were fully reacted, the temperature was lowered to room temperature, water was added, and the mixture was fully shaken. The mixture was allowed to stand, extracted, and the organic solvent was removed under reduced pressure for purification to obtain triphenylphosphine.

[0048] Example under solvent-free conditions: 0.5 mmol of triphenylphosphine sulfide and 1.0 mmol of potassium tert-butoxide were placed in a reactor, the gas in the reactor was replaced three times with 2 MPa of hydrogen, the temperature was raised to 150° C. under a hydrogen atmosphere, and the reaction was kept warm for 5 hours. After the triphenylphosphine sulfide and hydrogen were fully reacted, the temperature was lowered to room temperature, ethyl acetate and water were added, and after sufficient shaking, the mixture was allowed to stand, extracted, and the organic solvent was removed under reduced pressure for purification to obtain triphenylphosphine.

[0049] Preferably, the additive is potassium tert-butoxide.

[0050] Compared with the prior art, the advantages of the present invention are:

[0051] 1. The method provided by the present invention uses cheap and readily available hydrogen as a reducing agent to convert the phosphine-sulfur compound R into 1 R 2 R 3 PS is reduced to an organophosphine compound R 1 R 2 R 3 P. The reaction conditions are simple, applicable to a wide range and has good tolerance to functional groups.

[0052] Second, the present invention uses cheap and readily available additives to activate hydrogen, which can highly selectively convert phosphine-sulfur compounds R 1 R 2 R 3 PS is converted into organophosphine compound R 1 R 2 R 3 This method is low-cost, simple to operate, safe and pollution-free, and has high economic and market application value.

[0053] 3. The present invention provides a phosphine-sulfur compound R 1 R 2 R 3 PS reacts with hydrogen to form an organic phosphine compound R 1 R 2 R 3 P method, so that some phosphine sulfur compounds R 1 R 2 R 3 PS can be converted into high value-added organic phosphine compound R 1 R 2 R 3 P, effectively avoiding the waste of phosphorus resources. DETAILED DESCRIPTION

[0054] Example 1:

[0055] 0.5 mmol of triphenylphosphine sulfide, 1.0 mmol of potassium tert-butoxide, and 3.0 mL of toluene were placed in a reaction kettle, heated to 150°C in a hydrogen atmosphere at 2.0 MPa, kept warm for 5 hours, and then cooled to room temperature. The organic phase was washed with water twice, extracted, and the solvent was removed under reduced pressure to obtain 0.48 mmol of triphenylphosphine in a yield of 98%.

[0056] Example 2:

[0057] 0.5 mmol of tri(p-methylphenyl)phosphine sulfide, 1.0 mmol of potassium tert-butoxide, and 3.0 mL of toluene were placed in a reaction kettle, heated to 150° C. in a hydrogen atmosphere of 2.0 MPa, kept warm for 5 hours, cooled to room temperature, and the organic phase was washed with water twice, extracted, and the solvent was removed under reduced pressure. The organic phase was washed with water twice, and the solvent was removed under reduced pressure to obtain 0.48 mmol of tri(p-methylphenyl)phosphine in a yield of 96%.

[0058] Example 3:

[0059] 0.5 mmol of tri(o-methylphenyl)phosphine sulfide, 1.0 mmol of potassium tert-butoxide, and 3.0 mL of toluene were placed in a reaction kettle, heated to 150°C in a hydrogen atmosphere of 2.0 MPa, kept warm for 5 hours, cooled to room temperature, and the organic phase was washed with water twice. The solvent was removed under reduced pressure to obtain 0.49 mmol of tri(o-methylphenyl)phosphine in a yield of 98%.

[0060] Example 4:

[0061] 0.5 mmol of diphenylmethylphosphine sulfide, 1.0 mmol of potassium tert-butoxide, and 3.0 mL of toluene were placed in a reaction kettle, heated to 150°C in a hydrogen atmosphere at 2.0 MPa, kept warm for 5 hours, cooled to room temperature, and the organic phase was washed with water twice. The solvent was removed under reduced pressure to obtain 0.45 mmol of diphenylmethylphosphine in a yield of 90%.

[0062] Example 5:

[0063] 0.5 mmol of phenyldimethylphosphine sulfide, 1.0 mmol of potassium tert-butoxide, and 3.0 mL of toluene were placed in a reaction kettle, heated to 150°C in a hydrogen atmosphere at 2.0 MPa, kept warm for 5 hours, cooled to room temperature, and the organic phase was washed with water twice. The solvent was removed under reduced pressure to obtain 0.48 mmol of phenyldimethylphosphine in a yield of 96%.

[0064] Example 6:

[0065] 0.5 mmol of tri(p-methoxyphenyl)phosphine sulfide, 1.0 mmol of potassium tert-butoxide, and 3.0 mL of toluene were placed in a reaction kettle, heated to 150°C in a hydrogen atmosphere of 2.0 MPa, kept warm for 5 hours, cooled to room temperature, and the organic phase was washed with water twice. The solvent was removed under reduced pressure to obtain 0.43 mmol of tri(p-methoxyphenyl)phosphine in a yield of 86%.

[0066] Example 7:

[0067] 0.5 mmol of diphenyl-2-pyridinylphosphine sulfide, 1.0 mmol of potassium tert-butoxide, and 3.0 mL of toluene were placed in a reaction kettle, heated to 150°C in a hydrogen atmosphere of 2.0 MPa, kept warm for 5 hours, cooled to room temperature, and the organic phase was washed with water twice. The solvent was removed under reduced pressure to obtain 0.32 mmol of diphenyl-2-pyridinylphosphine in a yield of 64%.

[0068] Example 8:

[0069] 0.5 mmol of diphenyl-4-(vinyl)phenylphosphine sulfide, 1.0 mmol of potassium tert-butoxide, and 3.0 mL of toluene were placed in a reaction kettle, heated to 150° C. in a hydrogen atmosphere of 2.0 MPa, kept warm for 5 hours, cooled to room temperature, and the organic phase was washed with water twice. The solvent was removed under reduced pressure to obtain 0.32 mmol of diphenyl-4-(vinyl)phenylphosphine in a yield of 64%.

[0070] From Examples 1 to 8, it can be seen that using hydrogen as a reducing agent can effectively and highly selectively convert the phosphine-sulfur compound R 1 R 2 R 3 PS is reduced to an organophosphine compound R 1 R 2 R 3 P, and these reactions have high yields. The reduction method has good functional group tolerance and can retain other functional groups in the compound except the phosphine-sulfur bond.

[0071] Example 9:

[0072] Other conditions were the same as those in Example 1. The difference between Example 9 and Example 1 was that the reaction was carried out at 120° C. for 5 hours to obtain 0.16 mmol of triphenylphosphine with a yield of 32%.

[0073] Example 10:

[0074] Other conditions were the same as those in Example 1. The difference between Example 10 and Example 1 was that the reaction was carried out at 200° C. for 5 h, and 0.33 mmol of triphenylphosphine was obtained with a yield of 66%.

[0075] It can be seen from Examples 1, 9 and 10 that, while other reaction conditions remain unchanged, changing the reaction temperature, increasing or decreasing the reaction temperature can result in a higher yield of the product.

[0076] Example 11:

[0077] Other conditions were the same as those in Example 1. The difference between Example 11 and Example 1 was that Ph3PS with a purity of 85% was used to obtain 0.30 mmol of triphenylphosphine with a yield of 60%.

[0078] It can be seen from Examples 1 and 11 that, when other reaction conditions remain unchanged, even if the purity of triphenylphosphine sulfide changes, the yield of triphenylphosphine obtained by this method is still high.

[0079] Example 12:

[0080] Other conditions were the same as those in Example 1. The difference between Example 12 and Example 1 was that p-xylene was used as the solvent, and 0.48 mmol of triphenylphosphine was obtained with a yield of 96%.

[0081] Example 13:

[0082] Other conditions were the same as those in Example 1. The difference between Example 13 and Example 1 was that tetrahydrofuran was used as the solvent, and 0.38 mmol of triphenylphosphine was obtained with a yield of 76%.

[0083] Example 14:

[0084] Other conditions were the same as those in Example 1. The difference between Example 14 and Example 1 was that 1,4-dioxane was used as the solvent, and 0.41 mmol of triphenylphosphine was obtained with a yield of 82%.

[0085] It can be seen from Example 1 and Example 12 to Example 14 that when the other reaction conditions remain unchanged and the type of organic solvent is changed, the yield of the organic phosphine compound is the highest when the solvent is toluene.

[0086] Example 15:

[0087] Other conditions were the same as those in Example 1. The difference between Example 15 and Example 1 was that 1.6 MPa of hydrogen was used to obtain 0.48 mmol of triphenylphosphine with a yield of 96%.

[0088] Example 16:

[0089] Other conditions were the same as those in Example 1. The difference between Example 16 and Example 1 was that 1.0 MPa of hydrogen was used to obtain 0.36 mmol of triphenylphosphine with a yield of 72%.

[0090] Example 17:

[0091] Other conditions were the same as those in Example 1. The difference between Example 17 and Example 1 was that 5.0 MPa of hydrogen was used to obtain 0.49 mmol of triphenylphosphine with a yield of 98%.

[0092] Example 18:

[0093] Other conditions were the same as those in Example 1. The difference between Example 18 and Example 1 was that 3.0 MPa of hydrogen was used to obtain 0.49 mmol of triphenylphosphine with a yield of 98%.

[0094] From Examples 1 and 15 to 18, it can be seen that, when other reaction conditions remain unchanged, increasing the hydrogen pressure cannot make the organic phosphine compound R 1 R 2 R 3 The yield of P was significantly improved. Taking all factors into consideration, the optimal hydrogen pressure was 1.0N3.0MPa.

[0095] Example 19:

[0096] Other conditions were the same as those in Example 1. The difference between Example 19 and Example 1 was that the reaction occurred in the absence of a solvent, and 0.15 mmol of triphenylphosphine was obtained with a yield of 30%.

[0097] Example 20:

[0098] Other conditions were the same as those in Example 3. The difference between Example 20 and Example 3 was that the reaction occurred in the absence of a solvent, and 0.11 mmol of tri(o-methylphenyl)phosphine was obtained in a yield of 22%.

[0099] Example 21:

[0100] Other conditions were the same as those in Example 5. The difference between Example 21 and Example 5 was that the reaction took place in the absence of a solvent, and 0.1 mmol of phenyldimethylphosphine was obtained with a yield of 20%.

[0101] From Example 1 and Example 19 to Example 21, it can be seen that hydrogen can still convert phosphine-sulfur compound R into 1 R 2 R 3 PS is reduced to an organophosphine compound R 1 R 2 R 3 P.

[0102] Example 22:

[0103] Other conditions were the same as those in Example 1. The difference between Example 22 and Example 1 was that 0.5 mmol of triphenylphosphine sulfide and 0.5 mmol of potassium tert-butoxide were added to obtain 0.37 mmol of triphenylphosphine with a yield of 74%.

[0104] Example 23:

[0105] Other conditions were the same as those in Example 1. The difference between Example 23 and Example 1 was that 0.5 mmol of triphenylphosphine sulfide and 1.5 mmol of potassium tert-butoxide were added to obtain 0.49 mmol of triphenylphosphine with a yield of 98%.

[0106] Example 24:

[0107] Other conditions were the same as those in Example 1. The difference between Example 24 and Example 1 was that 0.5 mmol of triphenylphosphine sulfide and 2.5 mmol of potassium tert-butoxide were added to obtain 0.49 mmol of triphenylphosphine with a yield of 98%.

[0108] Example 25:

[0109] Other conditions were the same as those in Example 1. The difference between Example 25 and Example 1 was that 0.5 mmol of triphenylphosphine sulfide and 0.25 mmol of potassium tert-butoxide were added to obtain 0.21 mmol of triphenylphosphine with a yield of 42%.

[0110] From Example 1 and Example 22 to Example 25, it can be seen that other reaction conditions remain unchanged, and the additives and phosphine-sulfur compound R are changed. 1 R 2 R 3 The molar ratio of PS, the generated organic phosphine compound R 1 R 2 R 3 The yield of P was not significantly improved; therefore, the optimal molar ratio of the additive to triphenylphosphine sulfide was 0.5 to 3.0:1.

[0111] Example 26:

[0112] Other conditions were the same as those in Example 1. The difference between Example 26 and Example 1 was that the additive was potassium hydroxide, and 0.11 mmol of triphenylphosphine was obtained with a yield of 22%.

[0113] Example 27:

[0114] Other conditions were the same as those in Example 1. The difference between Example 27 and Example 1 was that the additive was lithium tert-butoxide, and 0.02 mmol of triphenylphosphine was obtained with a yield of 4%.

[0115] Example 28:

[0116] Other conditions were the same as those in Example 1. The difference between Example 28 and Example 1 was that the additive was sodium tert-butoxide, and 0.26 mmol of triphenylphosphine was obtained with a yield of 13%.

[0117] Example 29:

[0118] Other conditions were the same as those in Example 1. The difference between Example 29 and Example 1 was that the additive was cesium carbonate, and 0.03 mmol of triphenylphosphine was obtained with a yield of 6%.

[0119] From Example 1 and Example 26 to Example 29, it can be seen that, by changing the type of additive while keeping other reaction conditions unchanged, the reaction between hydrogen and phosphine-sulfur compound R 1 R 2 R 3 The reactivity of PS promotes the reaction of hydrogen with phosphine-sulfur compounds R 1 R 2 R 3 PS reacts to generate an organic phosphine compound R 1 R 2 R 3 P.

[0120] Comparative Example 1:

[0121] 0.5 mmol of triphenylphosphine sulfide, 1.0 mmol of potassium tert-butoxide, and 3.0 mL of toluene were placed in a reaction kettle, kept warm for 5 h, cooled to room temperature, and the organic phase was washed with water twice, extracted, and the solvent was removed under reduced pressure to obtain 0 mmol of triphenylphosphine with a yield of 0%.

[0122] Comparative Example 2:

[0123] 0.5 mmol of triphenylphosphine sulfide and 3.0 mL of toluene were placed in a reaction kettle, heated to 150°C in a hydrogen atmosphere at 2.0 MPa, kept warm for 5 hours, cooled to room temperature, and the organic phase was washed with water twice, extracted, and the solvent was removed under reduced pressure to obtain 0 mmol of triphenylphosphine with a yield of 0%.

[0124] It can be seen from Example 1, Comparative Example 1 and Comparative Example 2 that this solution is effective in preparing the organic phosphine compound R under the action of hydrogen and additives. 1 R 2 R 3 P, thereby achieving efficient utilization of phosphorus resources. And the organic phosphine compound R prepared in this scheme 1 R 2 R 3 The yield of P is significantly higher than that of Comparative Example 1 and Comparative Example 2.

[0125] In addition to the above embodiments, the present invention may also have other implementations. Any technical solution formed by equivalent replacement or equivalent transformation falls within the scope of protection required by the present invention.

Claims

1. A method for preparing an organic phosphine compound by highly selective reduction of a phosphine-sulfur compound with hydrogen, characterized in that: In a solvent-free or organic solvent, using hydrogen as a reducing agent, in a hydrogen atmosphere, phosphine-sulfur compounds R 1 R 2 R 3 PS is heated, reacted, separated and purified under the action of additives to obtain organic phosphine compound R 1 R 2 R 3 P; Among them, R 1 , R 2 and R 3 are independently selected from aromatic or aliphatic substituents, wherein R 1 , R 2 and R 3 At least one is selected from the aromatic group.

2. The method for preparing an organic phosphine compound by highly selective reduction of a phosphine-sulfur compound with hydrogen according to claim 1, characterized in that: R 1 , R 2 and R 3 Independently selected from C1-C 20 Straight-chain alkyl or branched-chain alkyl, alkenyl, C3-C 20 Cycloalkyl, C7-C 20 Aralkyl, C6-C 20 The aromatic and C2-C 20 The heterocyclic group.

3. The method for preparing an organic phosphine compound by highly selective reduction of a phosphine-sulfur compound with hydrogen according to claim 1, characterized in that: The additive is independently selected from one or more of potassium tert-butoxide, sodium tert-butoxide, lithium tert-butoxide, potassium hydroxide, sodium hydroxide, potassium carbonate, sodium carbonate, cesium carbonate, potassium chloride, sodium chloride, potassium fluoride, triethylamine, tetramethylethylamine and tricyclohexylamine.

4. The method for preparing an organic phosphine compound by highly selective reduction of a phosphine-sulfur compound with hydrogen according to claim 1, characterized in that: The pressure of the hydrogen is 1.0-5.0 MPa.

5. The method for preparing an organic phosphine compound by highly selective reduction of a phosphine-sulfur compound with hydrogen according to claim 1, characterized in that: The additive and the phosphine-sulfur compound R 1 R 2 R 3 The molar ratio of PS is 0.1 to 5:

1.

6. The method for preparing an organic phosphine compound by highly selective reduction of a phosphine-sulfur compound with hydrogen according to claim 1, characterized in that: The phosphine-sulfur compound R 1 R 2 R 3 When PS reacts with hydrogen in an organic solvent, the organic solvent reacts with the phosphine-sulfur compound R 1 R 2 R 3 The weight ratio of PS is 0.5 to 20:

1.

7. The method for preparing an organic phosphine compound by highly selective reduction of a phosphine-sulfur compound with hydrogen according to claim 1, characterized in that: The organic solvent is selected from one of a non-polar solvent of an alkane or aromatic hydrocarbon and a polar solvent containing a heteroatom.

8. The method for preparing an organic phosphine compound by highly selective reduction of a phosphine-sulfur compound with hydrogen according to claim 7, characterized in that: The non-polar solvent is selected from one or more of n-hexane, n-heptane, polyethylene, polypropylene, benzene, toluene, xylene and trimethylbenzene; the polar solvent is selected from one or more of tetrahydrofuran, 1,4-dioxane, N,N-dimethylformamide and N,N-dimethylacetamide.

9. The method for preparing an organic phosphine compound by highly selective reduction of a phosphine-sulfur compound with hydrogen according to claim 1, characterized in that: The reaction temperature is 50-250°C.

10. The method for preparing an organic phosphine compound by highly selective reduction of a phosphine-sulfur compound with hydrogen according to claim 1, characterized in that: Phosphine Sulfide Compounds R 1 R 2 R 3 PS is one or a mixture of any of triphenylphosphine sulfide, tri(o-methylphenyl)phosphine sulfide, phenyldimethylphosphine sulfide, tri(p-methylphenyl)phosphine sulfide, tri(p-methoxyphenyl)phosphine sulfide, diphenyl-2-pyridylphosphine sulfide, diphenylmethylphosphine sulfide and diphenyl-4-(vinyl)phenylphosphine sulfide.

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