A method for electrochemical preparation of phosphite diester compounds

Abstract

The present invention discloses an electrochemical method for preparing phosphite diester compounds. The method comprises: uniformly mixing an organic solvent, white phosphorus, an alcohol, and an electrolyte, and conducting an electrolytic reaction in a constant current mode to obtain the phosphite diester compounds. The method uses alcohol as a chlorine source and electro-oxidizes white phosphorus to produce the phosphite diester compounds with high Faradaic efficiency. Because this method directly uses inexpensive and readily available white phosphorus and alcohol as raw materials, and the only byproduct is hydrogen, it meets the requirements of green synthesis. Furthermore, the reaction has a high Faradaic efficiency, promising promising prospects for industrial application.

Description

Technical Field

[0001] The present invention relates to the technical field of organic synthesis, and in particular to an electrochemical preparation method of phosphite diester compounds. Background Art

[0002] Phosphite diesters are intermediates used in the production of important chemicals such as the insecticide thiophanate and the herbicide glyphosate. They can also be used as extractants and phosphate intermediates. They are used in the synthesis of the pesticides pyraclostrobin and fosetyl-aluminum, as well as in the synthesis of O,O-diethylphosphoryl chloride. They are also used in the synthesis of plasticizers and flame retardants.

[0003] Traditionally, phosphite diesters are synthesized through an alcoholysis reaction between phosphorus trichloride and alcohol. This process releases large amounts of hydrogen chloride, causing significant environmental pollution and corrosion to the equipment. Consequently, traditional methods for synthesizing phosphite diesters have drawbacks such as cumbersome steps and environmental concerns.

[0004] Therefore, it is necessary to develop an electrochemical preparation method for phosphite diester compounds to solve the above technical problems. Summary of the Invention

[0005] The present invention aims to provide an electrochemical preparation method for phosphite diester compounds, which can realize the conversion of white phosphorus into phosphite diester compounds in one step, with simple steps and environmental protection.

[0006] In order to achieve the above object, the present invention provides an electrochemical preparation method of a phosphite diester compound, the method comprising:

[0007] An organic solvent, white phosphorus, alcohol or phenol, an additive and an electrolyte are mixed evenly, and an electrolysis reaction is carried out in a constant current mode to obtain a phosphite diester compound.

[0008] Furthermore, the molar ratio of the white phosphorus to the additive is (1-3):1.

[0009] Furthermore, the additive includes at least one of lithium chloride, lithium perchlorate, lithium bromide and potassium iodide.

[0010] Furthermore, the organic solvent is selected from tetrahydrofuran, acetonitrile, dichloromethane, dimethyl sulfoxide and trifluoroethanol.

[0011] Furthermore, the electrolyte includes at least one of tetrabutylammonium tetrafluoroborate (TBABF4) and tetraethyltetrafluoroboric acid.

[0012] Furthermore, in the electrolysis reaction, an integrated electrolytic cell equipped with a stirrer and electrodes is used.

[0013] Furthermore, in the electrolysis reaction, the anode used includes one of a carbon sheet, graphite felt, carbon cloth, and a platinum sheet; and the cathode used is one of a nickel sheet, a carbon sheet, and stainless steel.

[0014] Furthermore, the alcohol or phenol has a structural formula of ROH, wherein R is selected from an alkyl group having less than ten carbon atoms, or a phenyl group and a phenyl group with a substituent, wherein the substituent is selected from a halogen, a cyano group, a nitro group, a trifluoromethyl group and a methoxy group.

[0015] Furthermore, the current of the electrolysis reaction is 5 to 30 mA.

[0016] Furthermore, the temperature of the electrolysis reaction is 0-40° C., and the time of the electrolysis reaction is 0.5-4 h.

[0017] One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:

[0018] An embodiment of the present invention provides an electrochemical method for preparing a phosphite diester compound, which uses inexpensive white phosphorus as a raw material to obtain a phosphite diester compound in a single step. The phosphite diester compound is obtained with a high Faradaic efficiency. Compared with traditional methods for synthesizing phosphite diester compounds, this method has low pollution, high atom utilization, low corrosion to equipment, and meets the requirements of green and safe production. This method directly uses inexpensive white phosphorus as a raw material, and the only byproduct is hydrogen, which meets the requirements of green synthesis. In addition, the reaction has a high Faradaic efficiency and has good prospects for industrial application. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 This is a chemical reaction equation for an electrochemical preparation method of a phosphite diester compound provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0021] The following will be combined with specific implementation methods and examples to specifically describe embodiments of the present invention, and the advantages and various effects of the embodiments of the present invention will be more clearly presented. It should be understood by those skilled in the art that these specific implementation methods and examples are used to illustrate embodiments of the present invention, rather than to limit the embodiments of the present invention.

[0022] Throughout this specification, unless otherwise specified, the terms used herein should be understood to have the same meaning as commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention relates. In the event of any conflict, the present specification shall take precedence.

[0023] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the embodiments of the present invention can be purchased from the market or prepared by existing methods.

[0024] The technical solution provided by the embodiments of the present invention is to solve the above technical problems, and the overall idea is based on the following:

[0025] According to a typical embodiment of the present invention, a method for electrochemically preparing a phosphite diester compound is provided, the method comprising:

[0026] An organic solvent, white phosphorus, alcohol, additives and electrolyte are mixed evenly, and an electrolysis reaction is carried out in a constant current mode to obtain a phosphite diester compound.

[0027] The chemical equation for this reaction is:

[0028]

[0029] In the above chemical reaction formula, R is selected from an alkyl group having less than ten carbon atoms, or a phenyl group and a phenyl group with a substituent, wherein the substituent is selected from a halogen, a cyano group, a nitro group, a trifluoromethyl group and a methoxy group.

[0030] In the above technical solution,

[0031] The molar ratio of the white phosphorus to the additive is (1-3):1. This molar ratio range is conducive to the complete completion of the reaction. If the molar ratio is not within the range of the present invention, it is not conducive to the high selective conversion of white phosphorus;

[0032] The additive includes at least one of lithium chloride, lithium perchlorate, lithium bromide and potassium iodide. The use of the additive is beneficial to improving the selectivity of the reaction;

[0033] The organic solvent is dimethyl sulfoxide. Using other solvents will result in a decrease in the Faradaic efficiency of the reaction. Compared with other solvents, white phosphorus has good solubility and conductivity in dimethyl sulfoxide, and has a good reaction effect.

[0034] The amount of organic solvent added is 5 to 14 mL. The amount of organic solvent added is 7 to 14 mL, and the concentration of white phosphorus is 0.07 to 0.15 M.

[0035] The electrolyte comprises at least one of tetrabutylammonium tetrafluoroborate and tetraethyltetrafluoroboric acid. The selection of this electrolyte promotes the Faradaic efficiency of the reaction. The electrolyte concentration ranges from 0.1 to 0.3M.

[0036] The concentration of the electrolyte in the electrolytic solvent is in the range of 0.1 to 0.3M.

[0037] The alcohol or phenol has a structural formula of ROH, where R is selected from an alkyl group having less than ten carbon atoms, or a phenyl group and a phenyl group with a substituent, wherein the substituent is selected from a halogen, a cyano group, a nitro group, a trifluoromethyl group, and a methoxy group. In a specific embodiment, ROH is an alkyl alcohol or a phenol. Preferably, the alkyl alcohol is an alkyl primary alcohol, such as methanol, ethanol, propanol, and butanol, and the phenol is phenol.

[0038] In the electrolytic reaction, an integrated electrolytic cell equipped with a stirrer and electrodes is used.

[0039] In the electrolysis reaction, the anode used includes one of a carbon sheet, graphite felt, and carbon cloth; and the cathode used is a nickel sheet.

[0040] The current of the electrolysis reaction is 5-40 mA. This current is conducive to the selectivity of the reaction. A current that is too low is not conducive to the efficient occurrence of the reaction, and a current that is too high is not conducive to the selectivity of the reaction.

[0041] The electrolysis reaction temperature is 0-40° C., and the electrolysis reaction time is 1-6 hours. The reason for the temperature being 0-40° C. is that if the temperature is too high, the reaction selectivity is poor, and if the temperature is too low, the raw material conversion rate is low.

[0042] The method further comprises: after the reaction is completed, performing organic extraction on the electrolyte with an organic solvent and then separating and purifying to obtain the product phosphite diester compound, or performing distillation on the electrolyte and low-temperature condensation to collect the product phosphite diester compound.

[0043] In summary, the present invention uses inexpensive white phosphorus as a raw material to obtain a phosphite diester compound in a single step. The phosphite diester compound is obtained with a high Faradaic efficiency. Compared with traditional methods for synthesizing phosphite diester compounds, this method has low pollution, high atom utilization, low corrosion to equipment, and meets the requirements of green and safe production. This method directly uses inexpensive white phosphorus as a raw material, and the only byproduct is hydrogen, which meets the requirements of green synthesis. In addition, the reaction has a high Faradaic efficiency and has good prospects for industrial application.

[0044] The electrochemical preparation method of a phosphite diester compound of the present application will be described in detail below with reference to examples and comparative experimental data.

[0045] Example 1

[0046]

[0047] Under argon atmosphere, white phosphorus (1,1 mmol), TBABF4 (1 mmol), lithium perchlorate (1 mmol), ethanol (5 mL), and tetrahydrofuran (5 mL) were added to a reaction tube. Carbon cloth served as the anode, and a carbon sheet served as the cathode. The mixture was stirred at room temperature for 4 hours at a constant current of 10.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum oil:ethyl acetate = 2:1) with a Faradaic efficiency of 51%.

[0048] Example 2

[0049] In this example, the additive was changed to potassium iodide, and other conditions were the same as in Example 1. The Faradaic efficiency of the product was 58%.

[0050] Example 3

[0051]

[0052] Under an argon atmosphere, white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), ethanol (5 mL), and tetrahydrofuran (5 mL) were added to a reaction tube. A carbon cloth served as the anode, and a carbon sheet served as the cathode. The mixture was stirred at room temperature for 4 hours at a constant current of 10.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum oil:ethyl acetate = 2:1) with a Faradaic efficiency of 53%.

[0053] Example 4

[0054]

[0055] Under argon atmosphere, white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), ethanol (5 mL), and tetrahydrofuran (5 mL) were added to a reaction tube. Carbon cloth served as the anode, and a carbon sheet served as the cathode. The mixture was stirred at room temperature for 4 hours at a constant current of 10.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum oil:ethyl acetate = 2:1) with a Faradaic efficiency of 61%.

[0056] Example 5

[0057] In this example, the solvent was changed to DMSO, and other conditions were the same as in Example 6. The Faradaic efficiency of the product was 70%.

[0058] Example 6

[0059]

[0060] Under argon atmosphere, white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), ethanol (1 mL), and DMSO (9 mL) were added to a reaction tube. Carbon cloth served as the anode, and a carbon sheet served as the cathode. The mixture was stirred at room temperature for 4 hours at a constant current of 10.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum:ethyl acetate = 2:1) with a Faradaic efficiency of 70%.

[0061] Example 7

[0062] In this embodiment, the anode is changed to a carbon sheet, and other conditions are the same as those in Example 11. The product Faraday efficiency is 73%.

[0063] Example 8

[0064] In this embodiment, the anode is changed to carbon felt, and other conditions are the same as those in Example 11. The product Faraday efficiency is 80%.

[0065] Example 9

[0066]

[0067] Under an argon atmosphere, white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), ethanol (1 mL), and DMSO (9 mL) were added to a reaction tube. Carbon felt served as the anode, and a carbon sheet served as the cathode. The mixture was stirred at room temperature for 4 hours at a constant current of 10.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum oil:ethyl acetate = 2:1) with a Faradaic efficiency of 87%.

[0068] Example 10

[0069] In this embodiment, the cathode is changed to a nickel sheet, and other conditions are the same as those in Example 14. The product Faraday efficiency is 92%.

[0070] Example 11

[0071] In this embodiment, the cathode is changed to stainless steel, and other conditions are the same as those in Example 14. The product Faraday efficiency is 99%.

[0072] Example 12

[0073]

[0074] Under an argon atmosphere, white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), ethanol (1 mL), and DMSO (9 mL) were added to a reaction tube; carbon felt served as the anode and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum:ethyl acetate = 2:1) with a Faradaic efficiency of 99%.

[0075] Example 13

[0076] In this example, the current was changed to 20 mA and the reaction time was changed to 2 h. Other conditions were the same as those in Example 14, and the Faradaic efficiency of the product was 88%.

[0077] Example 14

[0078]

[0079] Under argon, a reaction tube was charged with white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), methanol (1 mL), and DMSO (9 mL). Carbon felt served as the anode, and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum oil:ethyl acetate = 2:1) with a Faradaic efficiency of 78%.

[0080] Example 15

[0081]

[0082] Under an argon atmosphere, white phosphorus (1.1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), 2-chloroethanol (1 mL), and DMSO (9 mL) were added to a reaction tube. Carbon felt served as the anode, and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum:ethyl acetate = 2:1) with a Faradaic efficiency of 62%.

[0083] Example 16

[0084]

[0085] Under argon atmosphere, white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), ethylene glycol monomethyl ether (1 mL), and DMSO (9 mL) were added to a reaction tube; carbon felt served as the anode and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum:ethyl acetate = 2:1) with a Faradaic efficiency of 60%.

[0086] Example 17

[0087]

[0088] Under argon, white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), ethylene glycol monoethyl ether (1 mL), and DMSO (9 mL) were added to a reaction tube. Carbon felt served as the anode, and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum:ethyl acetate = 2:1) with a Faradaic efficiency of 84%.

[0089] Example 18

[0090]

[0091] Under an argon atmosphere, white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), isobutanol (1 mL), and DMSO (9 mL) were added to a reaction tube. Carbon felt served as the anode, and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum oil:ethyl acetate = 2:1) with a Faradaic efficiency of 99%.

[0092] Example 19

[0093]

[0094] Under argon, white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), isobutanol (1 mL), and DMSO (9 mL) were added to a reaction tube. Carbon felt served as the anode, and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum oil:ethyl acetate = 2:1) with a Faradaic efficiency of 89%.

[0095] Example 20

[0096]

[0097] Under argon, white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), cyclopropylmethanol (1 mL), and DMSO (9 mL) were added to a reaction tube. Carbon felt served as the anode, and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum:ethyl acetate = 2:1) with a Faradaic efficiency of 87%.

[0098] Example 21

[0099]

[0100] Under argon, a reaction tube was charged with white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), cyclohexanemethanol (1 mL), and DMSO (9 mL). Carbon felt served as the anode, and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum:ethyl acetate = 2:1) with a Faradaic efficiency of 68%.

[0101] Example 22

[0102]

[0103] Under argon atmosphere, white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), n-butanol (1 mL), and DMSO (9 mL) were added to a reaction tube. Carbon felt served as the anode, and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum:ethyl acetate = 2:1) with a Faradaic efficiency of 89%.

[0104] Example 23

[0105]

[0106] Under an argon atmosphere, white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), benzyl alcohol (1 mL), and DMSO (9 mL) were added to a reaction tube. Carbon felt served as the anode, and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum oil:ethyl acetate = 2:1) with a Faradaic efficiency of 44%.

[0107] Example 24

[0108]

[0109] Under an argon atmosphere, white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), phenylethanol (1 mL), and DMSO (9 mL) were added to a reaction tube; carbon felt served as the anode and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum:ethyl acetate = 2:1) with a Faradaic efficiency of 79%.

[0110] Example 25

[0111]

[0112] Under an argon atmosphere, white phosphorus (1,1 mmmol), TEABF4 (1 mmol), potassium iodide (1 mmol), isopropanol (1 mL), and DMSO (9 mL) were added to a reaction tube. Carbon felt served as the anode, and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum oil:ethyl acetate = 2:1) with a Faradaic efficiency of 73%.

[0113] Example 26

[0114]

[0115] Under argon atmosphere, white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), 3-pentanol (1 mL), and DMSO (9 mL) were added to a reaction tube; carbon felt served as the anode and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum:ethyl acetate = 2:1) with a Faradaic efficiency of 76%.

[0116] Example 27

[0117]

[0118] Under argon, white phosphorus (1.1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), cyclobutanol (1 mL), and DMSO (9 mL) were added to a reaction tube. Carbon felt served as the anode, and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum oil:ethyl acetate = 2:1) with a Faradaic efficiency of 95%.

[0119] Example 28

[0120]

[0121] Under argon, a reaction tube was charged with white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), cyclobutanol (1 mL), and DMSO (9 mL). Carbon felt served as the anode, and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum oil:ethyl acetate = 2:1) with a Faradaic efficiency of 55%.

[0122] Example 29

[0123]

[0124] Under argon atmosphere, white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), phenol (1 g), and DMSO (9 mL) were added to a reaction tube; carbon felt served as the anode and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum:ethyl acetate = 2:1) with a Faradaic efficiency of 76%.

[0125] Example 30

[0126]

[0127] Under argon atmosphere, white phosphorus (1,1 mmol), TEABF4 (1 mmol), potassium iodide (1 mmol), 4-cyanophenol (1 g), and DMSO (9 mL) were added to a reaction tube; carbon felt served as the anode and stainless steel served as the cathode. The mixture was stirred at room temperature for 8 hours at a constant current of 5.0 mA. At the end of the reaction, the product was purified by flash chromatography (petroleum:ethyl acetate = 2:1) with a Faradaic efficiency of 84%.

[0128] Comparative Example 1

[0129] In Comparative Example 1, the solvent was changed to acetonitrile. The other steps were the same as in Example 16, and the Faradaic efficiency of the product was only 5%.

[0130] Comparative Example 2

[0131] No additive was added in Comparative Example 2. The other steps were the same as in Example 16, and the Faradaic efficiency of the product was only 35%.

[0132] Comparative Example 3

[0133] In Comparative Example 3, the molar ratio of the white phosphorus to the additive was changed to 3:1. The other steps were the same as those in Example 1. The Faradaic efficiency of the product was only 46%.

[0134] Comparative Example 4

[0135] In Comparative Example 5, the current was 100 mA, and the other steps were the same as in Example 16. The Faradaic efficiency of the product was only 15%.

[0136] In summary, the Faradaic efficiency of the product phosphite diester compound in the embodiments of the present invention is superior to that of the comparative example. The Faradaic efficiency of the product of the embodiments of the present invention is 51%-99%. This shows that the product phosphite diester compound can be synthesized only when the reaction conditions are within the scope of the present invention.

[0137] Finally, it should be noted that the terms "comprises," "includes," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements, but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0138] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they are aware of the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0139] Obviously, those skilled in the art may make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the embodiments of the present invention. Thus, if such changes and modifications fall within the scope of the claims of the embodiments of the present invention and their equivalents, the embodiments of the present invention are intended to include such changes and modifications.

Claims

1. An electrochemical preparation method of phosphite diester compounds, characterized in that: The method comprises: An organic solvent, white phosphorus, alcohol or phenol, an additive and an electrolyte are mixed and electrolytically reacted in a constant current mode to obtain a phosphite diester compound, wherein the molar ratio of the white phosphorus to the additive is (1-3):1, the additive comprises at least one of lithium chloride, lithium perchlorate, lithium bromide and potassium iodide, the organic solvent is dimethyl sulfoxide, the electrolyte comprises at least one of tetrabutylammonium tetrafluoroborate and tetraethyltetrafluoroboric acid, the concentration range of the electrolyte in the electrolytic solvent is 0.1-0.3 M, the structural formula of the alcohol or phenol is ROH, R is selected from an alkyl group with less than ten carbon atoms, or a phenyl group and a phenyl group with a substituent, the substituent group is selected from a halogen, a cyano group, a nitro group, a trifluoromethyl group and a methoxy group, the current of the electrolytic reaction is 5-30 mA, the temperature of the electrolytic reaction is 0-40° C., and the time of the electrolytic reaction is 0.5-4 h. In the electrolysis reaction, an integrated electrolytic cell equipped with a stirrer and electrodes is used, and the anode used includes one of a carbon sheet, graphite felt, carbon cloth, and a platinum sheet; the cathode used is one of a nickel sheet, a carbon sheet, and stainless steel.

2. The electrochemical preparation method of a phosphite diester compound according to claim 1, characterized in that: The method further comprises: after the reaction is completed, performing organic extraction on the electrolyte with an organic solvent and then separating and purifying to obtain the product phosphite diester compound, or performing distillation on the electrolyte and low-temperature condensation to collect the product phosphite diester compound.

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