Preparation method of phosphate ester compound mediated by hypervalent iodine reagent

Abstract

The invention discloses a preparation method of a hypervalent iodine reagent mediated phosphate ester compound, which comprises the following steps: proportionally mixing diacetyl 3, 5-dimethyl isoxazole iodine, aromatic hydrocarbon and trifluoromethanesulfonic acid in a trifluoroacetic acid solution, stirring at normal temperature, and recrystallizing to obtain a hypervalent iodine reagent; and adding a hypervalent iodine reagent, triethylamine and diphenyl phosphate into a proper amount of toluene in proportion, stirring in an oil bath, and separating and purifying after reaction to obtain a target compound. The invention can provide the method for preparing the phosphate ester compound through direct phosphate esterification of a hypervalent iodine reagent mediated aromatic hydrocarbon C-H bond, and the method has the advantages of high yield, strong applicability, greenness, environmental protection and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of organic synthetic chemistry, and particularly relates to a method for preparing phosphate compounds mediated by hypervalent iodine reagents. Background Art

[0002] As an important class of organic compounds, phosphate compounds are widely used in multiple fields. They can be used as organophosphorus insecticides in agriculture, flame retardants and plasticizers in industry, antiviral drugs and anti-tumor preparations in the pharmaceutical field, and surfactants in the daily chemical industry for detergents, etc. However, existing synthesis methods such as the Atherton-Todd reaction, phosphate condensation method, and transition metal-catalyzed coupling reaction have problems such as harsh reaction conditions, potential heavy metal pollution risks, or low atom economy, which restrict their large-scale application. Therefore, it is particularly urgent to explore a new method for synthesizing phosphate compounds that is efficient and environmentally friendly.

[0003] In recent years, the breakthrough progress of hypervalent iodine reagents in green synthetic chemistry has provided new ideas for this challenge. Some hypervalent iodine compounds can effectively activate relatively inert C-H bonds, avoid the use of metal catalysts, and exhibit unique reaction activities in various chemical reactions such as oxidative coupling, C-H bond activation, and heteroatom introduction. By reasonably designing the reaction, it is expected to apply the efficient activation characteristics of hypervalent iodine reagents to the direct coupling of aromatic C-H bonds with phosphorus-containing compounds to explore a new method for preparing phosphate compounds.

[0004] Compared with traditional metal-catalyzed methods, this strategy does not use transition metal catalysts, can avoid the risk of heavy metal residues, has the advantage of being environmentally friendly, and is conducive to sustainable development.

[0005] At present, some methods for synthesizing phosphate compounds still have obvious limitations. For example, Chinese Patent CN109456265A (Application No. 201811590613.X) uses trialkylsilylamine to react with phosphoric acid to synthesize phosphate compounds, but the silyl ether by-products generated in this method are difficult to remove by conventional purification means (such as column chromatography), resulting in difficulty in improving the product purity and increasing the post-treatment cost; in addition, Chinese Patent CN114456041A (Application No. 202210156986.6) proposes a new preparation process for cyclic phosphates, which requires special reaction equipment to achieve high-temperature and high-pressure reaction conditions, significantly increasing equipment investment and energy consumption. Therefore, it is urgent to develop a new method for synthesizing phosphate compounds with mild conditions, high reaction efficiency, and environmental friendliness. Summary of the Invention

[0006] The purpose of this section is to outline some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of the present application, to avoid obscuring the purpose of this section, the abstract, and the title, but such simplifications or omissions shall not be used to limit the scope of the present invention.

[0007] In view of the above problems and / or those existing in the prior art, the present invention is proposed.

[0008] Therefore, an object of the present invention is to overcome the deficiencies in the prior art and provide a method for preparing phosphate compounds mediated by hypervalent iodine reagents.

[0009] To solve the above technical problems, the present invention provides the following technical solution: A method for preparing phosphate compounds mediated by hypervalent iodine reagents, characterized in that it includes:

[0010] Mix diacetyl 3,5-dimethylisoxazole iodine, aromatic hydrocarbon, and trifluoromethanesulfonic acid in a trifluoroacetic acid solution in proportion, stir at room temperature, and perform recrystallization treatment to obtain a hypervalent iodine reagent;

[0011] Add the hypervalent iodine reagent, triethylamine, and diphenyl phosphate to toluene, stir under an oil bath, wash and extract after the reaction is completed to obtain an organic phase, separate, purify, dry, and concentrate to obtain a phosphate compound mediated by the hypervalent iodine reagent.

[0012] As a preferred embodiment of the preparation method of the present invention, wherein: the molar ratio of diacetyl 3,5-dimethylisoxazole iodine, aromatic hydrocarbon, and trifluoromethanesulfonic acid is 1:1:1 to 3.

[0013] As a preferred embodiment of the preparation method of the present invention, wherein: during the stirring at room temperature, the stirring time is 1 to 24 hours.

[0014] As a preferred embodiment of the preparation method of the present invention, wherein: for the recrystallization treatment, the recrystallization reagent is one or more of diethyl ether and methyl tert-butyl ether.

[0015] As a preferred embodiment of the preparation method of the present invention, wherein: the molar ratio of the hypervalent iodine reagent, triethylamine, and diphenyl phosphate is 1:0.5 to 1.5:1.

[0016] As a preferred embodiment of the preparation method of the present invention, wherein: during the stirring under the oil bath, the oil bath temperature is 100 to 120 °C.

[0017] As a preferred embodiment of the preparation method of the present invention, wherein: for the extraction to obtain the organic phase, the extraction solvent is one or more of ethyl acetate and dichloromethane.

[0018] As a preferred embodiment of the preparation method of the present invention, wherein: the separation and purification is carried out by column chromatography, and the volume ratio of petroleum ether to ethyl acetate is 10:1.

[0019] As a preferred embodiment of the preparation method of the present invention, wherein: for the drying and concentration, the drying agent is one or more of anhydrous sodium sulfate and anhydrous magnesium sulfate.

[0020] Another object of the present invention is to overcome the deficiencies in the prior art and provide an application of a hypervalent iodine reagent-mediated phosphoric ester compound.

[0021] Advantages of the present invention:

[0022] (1) The method for preparing diaryliodonium provided by the present invention is simple to operate, has mild reaction conditions, high yield and high product purity, and has the potential for large-scale industrial production;

[0023] (2) The method of the present invention can be applied to various types of phosphoric ester compounds and aromatic hydrocarbon substrates, exhibits excellent reaction activity and selectivity in organic synthesis reactions, can be used for the synthesis of various organic compounds, and has broad application prospects;

[0024] (3) The present invention adopts a metal-free catalysis method, avoiding the use of metal catalysts, reducing environmental pollution, and being conducive to sustainable development. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts. Among them:

[0026] Figure 1 It is the synthesis route of phosphoric ester compound 1 in Example 1 of the present invention.

[0027] Figure 2 It is the characterization spectrum of phosphoric ester compound 1 in Example 1 of the present invention.

[0028] Figure 3 It is the synthesis route of phosphoric ester compound 2 in Example 2 of the present invention.

[0029] Figure 4 It is the characterization spectrum of phosphoric ester compound 2 in Example 2 of the present invention.

[0030] Figure 5 It is the synthesis route of phosphoric ester compound 3 in Example 3 of the present invention.

[0031] Figure 6 This is the characterization spectrum of the phosphate compound 3 in Example 3 of the present invention.

[0032] Figure 7 This is the synthesis route of the phosphate compound 4 in Example 4 of the present invention.

[0033] Figure 8 This is the characterization spectrum of the phosphate compound 4 in Example 4 of the present invention. Detailed implementation manners

[0034] To make the above objects, features, and advantages of the present invention more obvious and understandable, the following will describe the detailed implementation manners of the present invention in conjunction with the embodiments of the specification.

[0035] In the following description, many specific details are set forth to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described herein. Those skilled in the art can make similar generalizations without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0036] Secondly, the so-called "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that can be included in at least one implementation manner of the present invention. The appearances of "in one embodiment" in different places in this specification do not all refer to the same embodiment, nor are they separate or selectively exclusive embodiments from other embodiments.

[0037] The materials used in the embodiments of the present invention are all ordinary commercially available products unless otherwise specified.

[0038] The instruments used in the embodiments of the present invention are shown in Table 1.

[0039] Table 1

[0040]

[0041] Example 1

[0042] This example provides a preparation method for a phosphate compound. The synthesis route is as Figure 1 shown and includes the following steps:

[0043] (1) First, add the solvent trifluoroacetic acid (30.70 g, 0.27 mol) to a 150 mL round-bottom flask, then add diacetyl 3,5-dimethylisoxazole iodide (3.41 g, 0.01 mol), stir to completely dissolve it, and then sequentially add benzene (0.78 g, 0.01 mol) and trifluoromethanesulfonic acid (3.39 g, 0.02 mol);

[0044] (2) After all the materials are added, stir at room temperature for 24 h;

[0045] (3) After the reaction was completed, the hypervalent iodine reagent Ia was obtained by recrystallization with diethyl ether, 3.74 g of white solid;

[0046] (4) Under nitrogen protection, the hypervalent iodine reagent Ia (3.74 g, 8.3 mmol), diphenyl phosphate (2.08 g, 8.3 mmol), triethylamine (0.83 g, 8.3 mmol), and toluene (83 mL) were successively added to a 150 mL round-bottom flask;

[0047] (5) After the addition, the mixture was stirred for 2 h under reflux with oil bath at 120 °C;

[0048] (6) After the reaction was completed, the reaction solution was transferred to a separatory funnel, ethyl acetate was added, and the organic phase was washed successively with water and brine 3 times, and the aqueous phase was extracted with ethyl acetate 3 times. The target organic phase solution was collected in a conical flask;

[0049] (7) The above organic phase was dried over anhydrous sodium sulfate, filtered through a glass sand core funnel, and the liquid was collected in a eggplant-shaped flask. Then it was concentrated under vacuum, and an appropriate amount of silica gel powder of 100 - 200 mesh was added;

[0050] (8) The above silica gel powder sample was subjected to column chromatography (petroleum ether:ethyl acetate = 10:1) to obtain the phosphate compound 1, 2.08 g of colorless oil, and the yield was 77%.

[0051] The spectrum of the phosphate compound 1 is as Figure 2 shown, where (a) is 1 1H NMR spectrum (CDCl3, 401 MHz), (b) is 13 13C NMR spectrum (CDCl3, 101 MHz), (c) is 31 31P NMR spectrum (CDCl3, 162 MHz).

[0052] The NMR result analysis of the phosphate compound 1 is as follows: 1 1H NMR (401 MHz, Chloroform-d) δ 7.34 (t, J = 7.9 Hz, 6H), 7.29 - 7.14 (m, 9H). 13 13C NMR (101 MHz, Chloroform-d) δ 150.3, 150.2, 129.8, 125.5, 120.1, 120.0. 31 31P NMR (162 MHz, Chloroform-d) δ -17.60. IR: 1455, 1292, 1070 cm -1 . HRMS (DART): Calcd for C 18H 15 O4P(M+H) + 327.0782, found 327.0781.

[0053] Example 2

[0054] This example provides a method for preparing a phosphate compound. The synthesis route is as Figure 2 shown and includes the following steps:

[0055] (1) First, add the solvent trifluoroacetic acid (30.70 g, 0.27 mol) to a 150 mL round-bottom flask, then add diacetyl 3,5-dimethylisoxazole iodide (3.41 g, 0.01 mol), and stir to completely dissolve it. Then, successively add toluene (0.92 g, 0.01 mol) and trifluoromethanesulfonic acid (3.39 g, 0.02 mol);

[0056] (2) After all the materials are added, stir at room temperature for 24 h;

[0057] (3) After the reaction is completed, recrystallize with diethyl ether to obtain the hypervalent iodine reagent IIa, 3.58 g of white solid;

[0058] (4) Under nitrogen protection, add the hypervalent iodine reagent IIa (3.58 g, 7.8 mmol), diphenyl phosphate (1.95 g, 7.8 mmol), triethylamine (0.78 g, 7.8 mmol), and toluene (78 mL) to a 150 mL round-bottom flask in sequence;

[0059] (5) After adding, stir under reflux with an oil bath at 120 °C for 2 h;

[0060] (6) After the reaction is completed, transfer the reaction solution to a separatory funnel, add ethyl acetate, wash the organic phase with water and brine successively 3 times, extract the aqueous phase with ethyl acetate 3 times, and collect the target organic phase solution in a conical flask;

[0061] (7) After the above organic phase is dried with anhydrous sodium sulfate, filter it with a glass sand core funnel, collect the liquid in an eggplant-shaped flask, then concentrate it to dryness under vacuum, and add an appropriate amount of silica gel powder with a particle size of 100 - 200 mesh;

[0062] (8) The above silica gel powder sample is subjected to column chromatography (petroleum ether:ethyl acetate = 10:1) to obtain the phosphate compound 2, 2.65 g of colorless oil, and the yield is 99%.

[0063] The spectrum of the phosphate compound 2 is as Figure 4 shown, where (a) is 1 1H NMR spectrum (CDCl3, 401 MHz), (b) is 1313C NMR spectrum (CDCl3, 101 MHz), (c) is 31 31P NMR spectrum (CDCl3, 162 MHz).

[0064] The NMR results analysis of the phosphate compound 2 is as follows: 1 1H NMR (401 MHz, Chloroform-d) δ 7.34 (t, J = 7.8 Hz, 4H), 7.21 (dd, J = 17.2, 8.0 Hz, 6H), 7.12 (s, 4H), 2.32 (s, 3H). 13 13C NMR (101 MHz, Chloroform-d) δ 135.2, 130.3, 129.8, 125.5, 120.1, 120.0, 119.8, 119.7, 20.7. 31 31P NMR (162 MHz, Chloroform-d) δ -17.46. IR: 2925, 1455, 1306, 1071 cm -1 . HRMS (DART): Calcd for C 19 H 17 O4P (M + H) + 341.0938, found 341.0937.

[0065] Example 3

[0066] This example provides a preparation method of a phosphate compound, and the synthesis route is as Figure 3 shown, including the following steps:

[0067] (1) First, add the solvent trifluoroacetic acid (30.70 g, 0.27 mol) into a 150 mL round-bottom flask, then add diacetyl 3,5-dimethylisoxazole iodide (3.41 g, 0.01 mol), stir to dissolve it completely, and then add bromobenzene (1.57 g, 0.01 mol) and trifluoromethanesulfonic acid (3.39 g, 0.02 mol) in sequence;

[0068] (2) After all the materials are added, stir at room temperature for 24 h;

[0069] (3) After the reaction is completed, recrystallize with ether to obtain the hypervalent iodine reagent IIIa, 4.84 g of white solid;

[0070] (4) Then, under the protection of the inert gas nitrogen, add the hypervalent iodine reagent IIIa (4.84 g, 9.1 mmol), diphenyl phosphate (2.28 g, 9.1 mmol), triethylamine (0.91 g, 9.1 mmol), and toluene (91 mL) into a 150 mL round-bottom flask in sequence;

[0071] After the addition is complete, stir for 2 h under reflux condensation at 120 °C in an oil bath;

[0072] (6) After the reaction is completed, transfer the reaction solution to a separatory funnel, add ethyl acetate, wash the organic phase 3 times with water and brine in sequence, extract the aqueous phase 3 times with ethyl acetate, and collect the target organic phase solution in a conical flask;

[0073] (7) After the above organic phase is dried with anhydrous sodium sulfate, filter it with a glass sand core funnel, collect the liquid in a eggplant-shaped flask, then concentrate it to dryness under vacuum, and add an appropriate amount of silica gel powder with a mesh size of 100 - 200;

[0074] (8) The above silica gel powder sample is subjected to column chromatography (petroleum ether:ethyl acetate = 10:1) to obtain 3 of the phosphate ester compounds, 2.28 g of a colorless oil, and the yield is 62%.

[0075] The spectrum of the phosphate ester compound 3 is as Figure 6 shown, in which, (a) is 1 1H NMR spectrum (CDCl3, 401 MHz), (b) is 13 13C NMR spectrum (CDCl3, 101 MHz), (c) is 31 31P NMR spectrum (CDCl3, 162 MHz).

[0076] The NMR result analysis of the phosphate ester compound 3 is as follows: 1 1H NMR (401 MHz, Chloroform-d) δ 7.44 (d, J = 8.4 Hz, 2H), 7.34 (t, J = 7.8 Hz, 4H), 7.28 - 7.17 (m, 6H), 7.13 (d, J = 8.5 Hz, 2H). 13 13C NMR (101 MHz, Chloroform-d) δ 150.0, 149.3, 132.7, 129.7, 125.6, 121.8, 121.7, 119.9, 119.8, 118.5. 31 31P NMR (162 MHz, Chloroform-d) δ -17.69. IR: 1456, 1284, 1097, 559 cm - 1 . HRMS (DART): Calcd for C 18 H 14 BrO4P (M + H) + 404.9885, found 404.9885.

[0077] Example 4

[0078] This embodiment provides a method for preparing a phosphate compound, and the synthesis route is as Figure 4 shown, including the following steps:

[0079] (1) First, add the solvent trifluoroacetic acid (30.70 g, 0.27 mol) to a 150 mL round-bottom flask, then add diacetyl 3,5-dimethylisoxazole iodide (3.41 g, 0.01 mol), and stir to completely dissolve it. Then, successively add thiophene (0.84 g, 0.01 mol) and trifluoromethanesulfonic acid (3.39 g, 0.02 mol);

[0080] (2) After all the materials are added, stir at room temperature for 24 h;

[0081] (3) After the reaction is completed, recrystallize with diethyl ether to obtain the hypervalent iodine reagent Ⅳa, 3.20 g of white solid;

[0082] (4) Then, under the protection of the inert gas nitrogen, add the hypervalent iodine reagent Ⅳa (3.20 g, 7.1 mmol), diphenyl phosphate (1.78 g, 7.1 mmol), triethylamine (0.71 g, 7.1 mmol), and toluene (71 mL) to a 150 mL round-bottom flask in sequence;

[0083] (5) After adding, stir under reflux condensation at 120 °C in an oil bath for 2 h;

[0084] (6) After the reaction is completed, transfer the reaction solution to a separatory funnel, add ethyl acetate, wash the organic phase with water and brine successively 3 times, extract the aqueous phase with ethyl acetate 3 times, and collect the target organic phase solution in a conical flask;

[0085] (7) After the above organic phase is dried with anhydrous sodium sulfate, filter it with a glass sand core funnel, collect the liquid in an eggplant-shaped flask, then concentrate it to dryness under vacuum, and add an appropriate amount of silica gel powder with a particle size of 100 - 200 mesh;

[0086] (8) The above silica gel powder sample is subjected to column chromatography (petroleum ether:ethyl acetate = 10:1) to obtain the phosphate compound 4, 2.34 g of colorless oil, and the yield is 99%.

[0087] The spectrum of the phosphate compound 4 is as Figure 8 shown, where (a) is the 1 1H NMR spectrum (CDCl3, 401 MHz), (b) is the 13 13C NMR spectrum (CDCl3, 101 MHz), and (c) is the 31 31P NMR spectrum (CDCl3, 162 MHz).

[0088] The NMR results analysis of the phosphate compound 4 is as follows: 1 H NMR(401MHz,Chloroform-d)δ7.41(t,J=7.7Hz,4H),7.29(d,J=18.5Hz,6H),6.90-6.75(m,3H). 13 C NMR(101MHz,Chloroform-d)δ150.2,150.1,129.8,125.7,124.3,119.9,119.8,117.5,117.4,114.2,114.2. 31 P NMR(162MHz,Chloroform-d)δ-17.66.IR: 1589,1357,1074,1009,827cm -1 .HRMS(DART):Calcd for C 16 H 13 O4PS(M+H) + 333.0346,found333.0347.

[0089] Example 5

[0090] The difference between this example and Example 2 is that the molar ratio of diacetyl 3,5-dimethylisoxazole iodide, aromatic hydrocarbon, and trifluoromethanesulfonic acid in step (1) is replaced with 1:1:1.5, and the remaining steps are the same as those in Example 2. As a result, phosphate compound 2 was obtained, 2.26 g of colorless oil, and the yield was 85%.

[0091] Example 6

[0092] The difference between this example and Example 2 is that the molar ratio of diacetyl 3,5-dimethylisoxazole iodide, aromatic hydrocarbon, and trifluoromethanesulfonic acid in step (1) is replaced with 1:1:2.5, and the remaining steps are the same as those in Example 2. As a result, phosphate compound 2 was obtained, 2.34 g of colorless oil, and the yield was 88%.

[0093] Comparative Example 1

[0094] The difference between this comparative example and Example 2 is that the molar ratio of diacetyl 3,5-dimethylisoxazole iodide, aromatic hydrocarbon, and trifluoromethanesulfonic acid in step (1) is replaced with 1:1:1, and the remaining steps are the same as those in Example 2. As a result, phosphate compound 2 was obtained, 1.86 g of colorless oil, and the yield was 70%.

[0095] Comparative Example 2

[0096] The difference between this comparative example and Example 2 is that the molar ratio of diacetyl 3,5-dimethylisoxazole iodide, aromatic hydrocarbon, and trifluoromethanesulfonic acid in step (1) is replaced with 1:1:3, and the remaining steps are the same as those in Example 2. As a result, 1.99 g of the phosphate ester compound 2, a colorless oil, was obtained, with a yield of 75%.

[0097] Example 7

[0098] The difference between this example and Example 2 is that the molar ratio of the hypervalent iodine reagent, triethylamine, and diphenyl phosphate in step (4) is replaced with 1:0.8:1, and the remaining steps are the same as those in Example 2. As a result, 2.12 g of the phosphate ester compound 2, a colorless oil, was obtained, with a yield of 80%.

[0099] Example 8

[0100] The difference between this example and Example 2 is that the molar ratio of the hypervalent iodine reagent, triethylamine, and diphenyl phosphate in step (4) is replaced with 1:1.2:1, and the remaining steps are the same as those in Example 2. As a result, 2.18 g of the phosphate ester compound, a colorless oil, was obtained, with a yield of 82%.

[0101] Comparative Example 3

[0102] The difference between this comparative example and Example 2 is that the molar ratio of the hypervalent iodine reagent, triethylamine, and diphenyl phosphate in step (4) is replaced with 1:0.5:1, and the remaining steps are the same as those in Example 2. As a result, 1.73 g of the phosphate ester compound 2, a colorless oil, was obtained, with a yield of 65%.

[0103] Comparative Example 4

[0104] The difference between this comparative example and Example 2 is that the molar ratio of the hypervalent iodine reagent, triethylamine, and diphenyl phosphate in step (4) is replaced with 1:1.5:1, and the remaining steps are the same as those in Example 2. As a result, 1.86 g of the phosphate ester compound 2, a colorless oil, was obtained, with a yield of 70%.

[0105] The present invention combines the directional activation property of the hypervalent iodine reagent with the metal-free catalysis concept, and develops a simple method for the direct phosphorylation of aromatic C-H bonds to prepare phosphate ester compounds under mild reaction conditions, so as to overcome the limitations of the prior art and open up a new path for the environmentally friendly synthesis of structurally diverse phosphate ester compounds.

[0106] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the present invention.

Claims

1. A method for preparing phosphate ester compounds mediated by a hypervalent iodine reagent, characterized in that: Comprising, Mixing diacetyl 3,5-dimethylisoxazolium iodide, an aromatic hydrocarbon, and trifluoromethanesulfonic acid in a trifluoroacetic acid solution, stirring at room temperature, and performing recrystallization treatment to obtain a hypervalent iodine reagent; Adding the hypervalent iodine reagent, triethylamine, and diphenyl phosphate into toluene, stirring under an oil bath, washing and extracting after the reaction is completed to obtain an organic phase, separating, purifying, drying, and concentrating to obtain a hypervalent iodine reagent-mediated phosphate compound.

2. The preparation method according to claim 1, characterized in that: The molar ratio of diacetyl 3,5-dimethylisoxazolium iodide, the aromatic hydrocarbon, and trifluoromethanesulfonic acid is 1:1:1 to 3.

3. The preparation method according to claim 1, characterized in that: For the stirring at room temperature, the stirring time is 1 to 24 h.

4. The preparation method according to claim 1, characterized in that: For the recrystallization treatment, the recrystallization reagent is one or more of diethyl ether and methyl tert-butyl ether.

5. The preparation method according to claim 1, characterized in that: The molar ratio of the hypervalent iodine reagent, triethylamine, and diphenyl phosphate is 1:0.5 to 1.5:

1.

6. The preparation method according to claim 1, characterized in that: For the stirring under an oil bath, the oil bath temperature is 100 to 120 °C.

7. The preparation method according to claim 1, characterized in that: For the extraction to obtain the organic phase, the extraction solvent is one or more of ethyl acetate and dichloromethane.

8. The preparation method according to claim 1, characterized in that: The separation and purification uses column chromatography, and the volume ratio of petroleum ether to ethyl acetate is 10:

1.

9. The preparation method according to claim 1, wherein: For the drying and concentration, the drying substance is one or more of anhydrous sodium sulfate and anhydrous magnesium sulfate.

10. Application of the hypervalent iodine reagent-mediated phosphate compound prepared by the preparation method according to any one of claims 1 to 9.

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