A method for preparing 2-benzoyl-1,10-phenanthroline

Abstract

The present invention provides a method for preparing 2-benzoyl-1,10-phenanthroline, and relates to the field of olefin polymerization. The preparation method of the present invention comprises the following steps: compound a reacts with compound b in a solvent to obtain compound c; wherein X is a halogen. The preparation method of the present invention directly synthesizes 2-benzoyl-1,10-phenanthroline by an addition reaction of a phenyl Grignard reagent and a cyano group. The preparation of 2-benzoyl-1,10-phenanthroline by the method can simplify the operation, shorten the reaction steps and the production cycle, reduce the production cost, and improve the production efficiency. In addition, the synthesis method reduces the use of highly toxic chemicals, improves production safety, and reduces pollution to the environment. The preparation method of the present invention overcomes the problems existing in the existing method for preparing 2-benzoyl-1,10-phenanthroline, and has good application prospects. #imgabs0#

Description

Technical Field

[0001] The invention relates to the field of olefin polymerization, and in particular to a method for preparing 2-benzoyl-1,10-phenanthroline. Background Art

[0002] 2-Benzoyl-1,10-phenanthroline is a key intermediate of ethylene polymerization catalyst. In recent years, with the continuous development of the polyolefin industry, linear α-olefins have been widely used in the fields of ethylene comonomers, surfactant synthesis intermediates, plasticizer alcohols, synthetic lubricants and oil additives. The demand for α-olefins is growing rapidly worldwide. At present, most α-olefins are prepared by ethylene polymerization, and 2-benzoyl-1,10-phenanthroline is a key intermediate of ethylene polymerization catalyst.

[0003]

[0004] 2-Benzoyl-1,10-phenanthroline

[0005] The document "Iron complexes bearing 2-imino-1,10-phenanthrolinyl ligands as highly active catalysts for ethylene oligomerization" (Wen-Hua Sun et al., Organometallics, 2006, 25, 666-677) discloses a method for preparing 2-benzoyl-1,10-phenanthroline, which comprises firstly reacting the cyano group in 2-cyano-1,10-phenanthroline to produce a carboxyl group, and then reacting the cyano group with thionyl chloride, anhydrous aluminum chloride and benzene to generate 2-benzoyl-1,10-phenanthroline. Specifically, NaOH solution is added to a 95% ethanol solution of 2-cyano-1,10-phenanthroline, some ethanol is removed after the reaction, and concentrated hydrochloric acid is used in an ice-water bath to make the residue slightly acidic, the precipitate is filtered, washed with water, and dried in vacuum to obtain a yellow-brown solid 1,10-phenanthroline-2-carboxylic acid, 1,10-phenanthroline-2-carboxylic acid is refluxed with thionyl chloride for 6 hours, and then the residual thionyl chloride is removed under reduced pressure. The obtained light yellow solid is refluxed in benzene with anhydrous aluminum chloride for 4 hours, and the obtained red solution is cooled to room temperature, stirred for 12 hours, and then refluxed for 6 hours. After the solution is cooled to room temperature, it is poured into distilled water at 0°C and the aqueous layer is extracted with chloroform. The combined organic phase is dried with anhydrous sodium sulfate and concentrated in vacuum to obtain a white solid 2-benzoyl-1,10-phenanthroline.

[0006]

[0007] However, the synthesis method has long process steps, complex operation, low production efficiency, a yield of only 48%, a purity of only 90%, high cost, and is not environmentally friendly; and the solvents benzene and thionyl chloride used in the synthesis method are both toxic solvents with high volatility, posing a strong safety hazard.

[0008] Therefore, it is necessary to study a new method for synthesizing 2-benzoyl-1,10-phenanthroline with a short process, high production efficiency, low cost, environmental friendliness and safety. Summary of the invention

[0009] The object of the present invention is to provide a method for preparing 2-benzoyl-1,10-phenanthroline.

[0010] The present invention provides a method for preparing 2-benzoyl-1,10-phenanthroline, which comprises the following steps:

[0011]

[0012] Compound a reacts with compound b in a solvent to obtain compound c;

[0013] Wherein, X is a halogen.

[0014] Further, X is fluorine, chlorine, bromine or iodine;

[0015] Preferably, X is bromine.

[0016] Furthermore, the method comprises the following steps:

[0017] (1) Compound a is dissolved in an organic solvent, compound b is added, and the mixture is reacted;

[0018] (2) After the reaction is completed, the reaction solution is purified to obtain compound c;

[0019] Preferably,

[0020] In step (1), the equivalent ratio of compound a to compound b is 1:1 to 2.5;

[0021] And / or, in step (1), the mass ratio of compound a to organic solvent is 1:10-20.

[0022] Further,

[0023] In step (1), the organic solvent is selected from any one or more of toluene, cyclohexane, ether, tetrahydrofuran, benzene, xylene, methyl tert-butyl ether, and 2-methyltetrahydrofuran;

[0024] And / or, in step (1), when compound b is added, compound b is dissolved in a solvent;

[0025] And / or, in step (1), when compound b is added, the temperature is -25 to 25°C;

[0026] And / or, in step (1), the reaction temperature is -25 to 25°C;

[0027] And / or, in step (1), the reaction time is 0.1 to 2 hours;

[0028] And / or, in step (2), the purification method comprises the following steps: pouring the reaction solution into 10% dilute hydrochloric acid to quench the reaction, then concentrating under reduced pressure to remove the organic solvent, adding an extraction solvent for extraction, taking the organic phase and concentrating it under reduced pressure to dryness, adding a crystallization solvent for dispersion, filtering, and drying.

[0029] Further,

[0030] In step (1), the organic solvent is selected from tetrahydrofuran or 2-methyltetrahydrofuran;

[0031] And / or, in step (1), the solvent for dissolving compound b is selected from any one or a mixture of two or more of toluene, xylene, cyclohexane, propyl ether, butyl ether, amyl ether, isopropyl ether, isoamyl ether, anisole, anhydrous ethyl ether, methyl tert-butyl ether, tetrahydrofuran or 2-methyltetrahydrofuran;

[0032] And / or, in step (1), when compound b is added, the temperature is -20 to 5°C;

[0033] And / or, in step (1), the compound b is added dropwise;

[0034] And / or, in step (1), the reaction temperature is -20 to 5°C;

[0035] And / or, in step (1), the reaction time is 0.5 to 1 hour;

[0036] And / or, in step (2), the temperature of the 10% dilute hydrochloric acid is -5 to 15°C;

[0037] And / or, in step (2), the volume ratio of the product after the reduced pressure concentration to remove the organic solvent to the extraction solvent is 1:1-2;

[0038] And / or, in step (2), the mass ratio of the organic phase after being concentrated under reduced pressure to dryness to the mass ratio of the crystallization solvent is 1:2 to 6.

[0039] Further,

[0040] In step (1), when compound b is added, the temperature is -15 to 0°C;

[0041] And / or, in step (1), the reaction temperature is -15 to 0°C;

[0042] And / or, in step (2), the extraction solvent is selected from ethyl acetate, chloroform, dichloromethane, 2-methyltetrahydrofuran or toluene;

[0043] And / or, in step (2), the crystallization solvent is selected from any one of petroleum ether, n-heptane, methyl tert-butyl ether, ethyl acetate, toluene, or a mixture of two or more thereof;

[0044] Preferably,

[0045] In step (2), the extraction solvent is selected from dichloromethane or chloroform;

[0046] And / or, in step (2), the crystallization solvent is selected from methyl tert-butyl ether or a mixed solution of ethyl acetate and n-heptane.

[0047] Furthermore, the preparation method of compound b comprises the following steps:

[0048]

[0049] In a solvent, compound d is reacted with magnesium to obtain compound b;

[0050] Wherein, X is a halogen;

[0051] Preferably, X is fluorine, chlorine, bromine or iodine.

[0052] Furthermore, the preparation method of compound b comprises the following steps:

[0053] (1) adding part of compound d and a solvent to magnesium to initiate a reaction;

[0054] (2) After the reaction is initiated, the remaining compound d and a solvent mixed solution are added and reacted to obtain compound b.

[0055] Furthermore, the mass ratio of the compound d to magnesium is 1:0.1-0.3;

[0056] And / or, the reaction temperature is 20-60°C;

[0057] And / or, the reaction time is 0.5 to 3 hours;

[0058] Preferably, the mass ratio of the compound d to magnesium is 1:0.15-0.23;

[0059] And / or, the reaction temperature is 20-50°C;

[0060] And / or, the reaction time is 1 to 2 hours.

[0061] Further, the solvent is selected from any one or a mixture of two or more of toluene, xylene, cyclohexane, propyl ether, butyl ether, amyl ether, isopropyl ether, isoamyl ether, anisole, anhydrous ethyl ether, methyl tert-butyl ether, tetrahydrofuran or 2-methyltetrahydrofuran;

[0062] And / or, the compound d is selected from phenyl chloride, phenyl bromide, phenyl iodine, and phenyl fluoride;

[0063] Preferably,

[0064] The solvent is selected from tetrahydrofuran and 2-methyltetrahydrofuran;

[0065] And / or, the compound d is selected from phenyl bromide.

[0066] Compared with the prior art, the present invention has the following beneficial effects:

[0067] The present invention provides a method for preparing 2-benzoyl-1,10-phenanthroline, wherein the method directly synthesizes 2-benzoyl-1,10-phenanthroline by an addition reaction of a phenyl Grignard reagent and a cyano group. The method for preparing 2-benzoyl-1,10-phenanthroline can simplify the operation, shorten the reaction steps and the production cycle, reduce the production cost, and improve the production efficiency. The synthesis method reduces the use of highly toxic chemicals, improves production safety, and reduces pollution to the environment. The preparation method of the present invention overcomes the problems existing in the existing method for preparing 2-benzoyl-1,10-phenanthroline, and has good application prospects.

[0068] Obviously, according to the above contents of the present invention, in accordance with common technical knowledge and customary means in the art, without departing from the above basic technical ideas of the present invention, other various forms of modification, replacement or change may be made.

[0069] The above contents of the present invention are further described in detail below through specific implementation methods in the form of embodiments. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following examples. All technologies realized based on the above contents of the present invention belong to the scope of the present invention. DETAILED DESCRIPTION

[0070] The raw materials and equipment used in the specific embodiments of the present invention are all known products and are obtained by purchasing commercially available products.

[0071] In the present invention, 2-cyano-1,10-phenanthroline is a compound with CAS No. 1082-19-5.

[0072] In the present invention, the reaction is carried out under the protection of an inert gas, and the inert gas is preferably nitrogen.

[0073] Example 1. Preparation of 2-benzoyl-1,10-phenanthroline of the present invention

[0074] a. Synthesis of phenylmagnesium chloride

[0075] Put 3.1g magnesium chips into a 100ml three-necked flask, add 5.0ml tetrahydrofuran and 2.0g chlorobenzene under nitrogen protection and magnetic stirring. After initiation, add a mixed solution of 9.0g chlorobenzene and 39.0ml tetrahydrofuran dropwise at a temperature below 50°C, and continue stirring at this temperature for 3h. Then cool the reaction mixture to room temperature to obtain 52.0g phenylmagnesium chloride tetrahydrofuran solution.

[0076] b. Synthesis of 2-benzoyl-1,10-phenanthroline

[0077] Under nitrogen protection, add 10.0g 2-cyano-1,10-phenanthroline to a 500ml three-necked flask, dissolve it with 146.6ml tetrahydrofuran, control the temperature to 0-5℃, drop the phenylmagnesium chloride tetrahydrofuran solution (phenylmagnesium chloride 13.3g) prepared in step a, and continue to react until complete after the addition. Quench the reaction with 64.1g 10% dilute hydrochloric acid, concentrate under reduced pressure to remove tetrahydrofuran, extract with 300.0ml dichloromethane, and combine the organic phases. The organic phase is concentrated to dryness under reduced pressure, 70.0g methyl tert-butyl ether is added, stirred and dispersed, filtered, and dried to obtain 5.52 light yellow products with a purity of 94% and a yield of 40%. The product was determined to be 2-benzoyl-1,10-phenanthroline by nuclear magnetic resonance and mass spectrometry. MS: [M+1]=285.15; HNMR (400M, DMSO): δ=9.08(dd,,1H),8.72(d,1H),8.52(dd,1H) ,8.27(d,1H),8.23(m,2H),8.11(dd,2H),7.79(dd,1H),7.72(m,1H),7.58(m,2H).

[0078] Example 2, Preparation of 2-benzoyl-1,10-phenanthroline of the present invention

[0079] a. Synthesis of Phenyl Magnesium Bromide

[0080] Put 3.1g magnesium chips into a 100ml three-necked flask, add 5.0ml tetrahydrofuran and 2.0g bromobenzene under nitrogen protection and magnetic stirring. After initiation, add a mixed solution of 13.3g bromobenzene and 56.5ml tetrahydrofuran at a temperature below 50°C, and continue stirring at this temperature for 3h. Then cool the reaction mixture to room temperature to obtain 71.0g phenylmagnesium bromide tetrahydrofuran solution.

[0081] b. Synthesis of 2-benzoyl-1,10-phenanthroline

[0082] Under nitrogen protection, add 10.0g 2-cyano-1,10-phenanthroline to a 500ml three-necked flask, dissolve it with 146.6ml tetrahydrofuran, control the temperature at 0-5°C, add the phenylmagnesium bromide tetrahydrofuran solution (phenylmagnesium bromide 17.6g) prepared in step a, and continue to react until complete after the addition. Quench the reaction with 64.1g 10% dilute hydrochloric acid, concentrate under reduced pressure to remove tetrahydrofuran, extract with 300.0ml dichloromethane, and combine the organic phases. The organic phase is concentrated to dryness under reduced pressure, 70.0g methyl tert-butyl ether is added, stirred and dispersed, filtered, and dried to obtain 6.92g of light yellow product with a purity of 95% and a yield of 50%. The product was determined to be 2-benzoyl-1,10-phenanthroline by nuclear magnetic resonance and mass spectrometry. MS: [M+1]=285.15; HNMR (400M, DMS O): δ=9.08(dd,,1H),8.72(d,1H),8.52(dd,1H),8.27(d,1H),8.23(m,2H),8.11(dd,2H),7.79(dd,1H),7.72(m,1H),7.58(m,2H).

[0083] Example 3, Preparation of 2-benzoyl-1,10-phenanthroline of the present invention

[0084] a. Synthesis of Phenyl Magnesium Bromide

[0085] Put 3.1g magnesium chips into a 100ml three-necked flask, add 5.0ml 2-methyltetrahydrofuran and 2.0g bromobenzene under nitrogen protection and magnetic stirring. After initiation, add a mixed solution of 13.3g bromobenzene and 56.5ml 2-methyltetrahydrofuran dropwise at a temperature below 50°C, and continue stirring at this temperature for 3h. Then cool the reaction mixture to room temperature to obtain 70.0g phenylmagnesium bromide 2-methyltetrahydrofuran solution.

[0086] b. Synthesis of 2-benzoyl-1,10-phenanthroline

[0087] Under nitrogen protection, add 10.0g 2-cyano-1,10-phenanthroline to a 500ml three-necked flask, dissolve it with 146.6ml 2-methyltetrahydrofuran, control the temperature at -15~-5℃, dropwise add 24% phenylmagnesium bromide 2-methyltetrahydrofuran solution (phenylmagnesium bromide 17.6g) prepared in step a, and continue to react until complete after the addition. Quench the reaction with 64.1g 10% dilute hydrochloric acid, concentrate under reduced pressure to remove 2-methyltetrahydrofuran, extract with 300.0ml chloroform, and combine the organic phases. The organic phase is concentrated under reduced pressure to dryness, and 35.0g ethyl acetate and 35g n-heptane are added for stirring and dispersion, filtered, and dried to obtain 8.4g of light yellow product with a purity of 96% and a yield of 61%. MS: [M+1]=285.15; HNMR (400M, DMSO): δ=9.08(dd,,1H),8.72(d,1H),8.52(dd,1H) ,8.27(d,1H),8.23(m,2H),8.11(dd,2H),7.79(dd,1H),7.72(m,1H),7.58(m,2H).

[0088] Example 4, Preparation of 2-benzoyl-1,10-phenanthroline of the present invention

[0089] a. Synthesis of Phenyl Magnesium Bromide

[0090] Put 3.1g magnesium chips into a 100ml three-necked flask, add 5.0ml anhydrous ether and 2.0g bromobenzene under nitrogen protection and magnetic stirring. After initiation, add a mixed solution of 13.3g bromobenzene and 56.5ml anhydrous ether dropwise at a temperature below 50°C, and continue stirring at this temperature for 3h. Then cool the reaction mixture to room temperature to obtain 61.0g phenylmagnesium bromide ether solution.

[0091] b. Synthesis of 2-benzoyl-1,10-phenanthroline

[0092] Under nitrogen protection, add 10.0g 2-cyano-1,10-phenanthroline to a 500ml three-necked flask, dissolve it with 146.6ml tetrahydrofuran, control the temperature at -20~-10℃, add the ether solution of phenylmagnesium bromide prepared in step a (17.6g phenylmagnesium bromide), and continue to react until complete after the addition. Quench the reaction with 64.1g 10% dilute hydrochloric acid, concentrate under reduced pressure to remove ether, extract with 300.0ml dichloromethane, and combine the organic phases. Concentrate the organic phase under reduced pressure to dryness, add 70g methyl tert-butyl ether, stir and disperse, filter, and dry to obtain 10.08g light yellow product with a purity of 98% and a yield of 73%. MS: [M+1]=285.15; HNMR (400M, DMSO): δ=9.08(dd,,1H),8.72(d,1H),8.52(dd,1H) ,8.27(d,1H),8.23(m,2H),8.11(dd,2H),7.79(dd,1H),7.72(m,1H),7.58(m,2H).

[0093] Example 5. Other preparation methods

[0094] Referring to the similar method described in step a of Example 4, bromobenzene was replaced with chlorobenzene, iodobenzene or fluorobenzene, and the anhydrous ether solvent was replaced with anisole, 2-methyltetrahydrofuran, methyl tert-butyl ether, tetrahydrofuran to prepare different Grignard reagent solutions. The synthesis process conditions of step b were the same as those of Example 4 to prepare 2-benzoyl-1,10-phenanthroline. The results are shown in Table 1.

[0095] Table 1. Yield and purity of 2-benzoyl-1,10-phenanthroline prepared by other preparation methods

[0096]

[0097]

[0098] It can be seen from the above examples that the preparation of 2-benzoyl-1,10-phenanthroline by the synthesis method of the present invention has simple steps, high yield and purity of the prepared 2-benzoyl-1,10-phenanthroline, and high production efficiency. The best effect is achieved when the Grignard reagent is phenylmagnesium bromide.

[0099] Example 6: Preparation of 2-benzoyl-1,10-phenanthroline for scaled-up production according to the present invention

[0100] a. Synthesis of Phenyl Magnesium Bromide

[0101] Put 10.85kg magnesium chips into the reactor, add 15.6kg anhydrous ether and 7.0kg bromobenzene under nitrogen protection and magnetic stirring. After initiation, add a mixed solution of 46.55kg bromobenzene and 176.0kg anhydrous ether dropwise at a temperature below 50°C, and continue stirring at this temperature for 3h. Then cool the reaction mixture to room temperature to obtain 253.0kg phenylmagnesium bromide anhydrous ether solution.

[0102] b. Synthesis of 2-benzoyl-1,10-phenanthroline

[0103] Under nitrogen protection, add 35.0kg 2-cyano-1,10-phenanthroline to the reactor, dissolve it with 456.6kg tetrahydrofuran, control the temperature at 0-5°C, add the ether solution of phenylmagnesium bromide prepared in step a (61.6kg phenylmagnesium bromide), and continue to react until complete after the addition. Quench the reaction with 224.35kg 10% dilute hydrochloric acid, concentrate under reduced pressure to remove ether, extract with 1386.0kg dichloromethane, and combine the organic phases. The organic phase is concentrated to dryness under reduced pressure, and 245.0kg methyl tert-butyl ether is added, stirred and dispersed, filtered, and dried to obtain 35.28kg of light yellow product with a purity of 98% and a yield of 73%. The product was determined to be 2-benzoyl-1,10-phenanthroline by nuclear magnetic resonance and mass spectrometry. MS: [M+1]=285.15; HNMR (400M, DMSO): δ=9.08(dd,,1H),8.72(d,1H),8.52(dd,1H) ,8.27(d,1H),8.23(m,2H),8.11(dd,2H),7.79(dd,1H),7.72(m,1H),7.58(m,2H).

[0104] In summary, the present invention provides a method for preparing 2-benzoyl-1,10-phenanthroline, in which phenyl Grignard reagent and cyano group are subjected to an addition reaction to directly synthesize 2-benzoyl-1,10-phenanthroline. The method for preparing 2-benzoyl-1,10-phenanthroline can simplify the operation, shorten the reaction steps and the production cycle, reduce the production cost, and improve the production efficiency. In addition, the synthesis method reduces the use of highly toxic chemicals, improves production safety, and reduces environmental pollution. The preparation method of the present invention overcomes the problems existing in the existing method for preparing 2-benzoyl-1,10-phenanthroline, and has good application prospects.

Claims

1. A method for preparing 2-benzoyl-1,10-phenanthroline, characterized in that: It includes the following steps: (1) Compound a is dissolved in an organic solvent, compound b is added, and the mixture is reacted; the organic solvent is selected from any one or more of diethyl ether, tetrahydrofuran, and 2-methyltetrahydrofuran; (2) After the reaction is completed, the reaction solution is purified to obtain compound c; The preparation method of the compound b comprises the following steps: In a solvent, compound d is reacted with magnesium to obtain compound b; the solvent is selected from any one or a mixture of two or more of anhydrous ether, methyl tert-butyl ether, tetrahydrofuran or 2-methyltetrahydrofuran; Wherein, X is a halogen.

2. The method according to claim 1, characterized in that: The X is bromine.

3. The method according to claim 1, characterized in that: In step (1), the equivalent ratio of compound a to compound b is 1:1 to 2.5; Alternatively, in step (1), the mass ratio of compound a to the organic solvent is 1:10 to 20.

4. The method according to claim 3, characterized in that: In step (1), when adding compound b, compound b is dissolved in an organic solvent; Or, in step (1), when compound b is added, the temperature is -25 to 25°C; Or, in step (1), the reaction temperature is -25 to 25°C; Or, in step (1), the reaction time is 0.1 to 2 hours; Alternatively, in step (2), the purification method comprises the following steps: pouring the reaction solution into 10% dilute hydrochloric acid to quench the reaction, then concentrating under reduced pressure to remove the organic solvent, adding an extraction solvent for extraction, taking the organic phase and concentrating it under reduced pressure to dryness, adding a crystallization solvent for dispersion, filtering, and drying.

5. The method according to claim 4, characterized in that: In step (1), the organic solvent is selected from tetrahydrofuran or 2-methyltetrahydrofuran; Or, in step (1), the solvent for dissolving compound b is selected from any one or a mixture of two or more of anhydrous ether, methyl tert-butyl ether, tetrahydrofuran or 2-methyltetrahydrofuran; Or, in step (1), when compound b is added, the temperature is -20 to 5°C; Or, in step (1), the compound b is added dropwise; Or, in step (1), the reaction temperature is -20 to 5°C; Or, in step (1), the reaction time is 0.5 to 1 hour; Or, in step (2), the temperature of the 10% dilute hydrochloric acid is -5 to 15°C; Or, in step (2), the volume ratio of the product after the organic solvent is removed by concentration under reduced pressure to the extraction solvent is 1:1-2; Alternatively, in step (2), the mass ratio of the organic phase after being concentrated under reduced pressure to dryness to the mass ratio of the crystallization solvent is 1:2 to 6.

6. The method according to claim 5, characterized in that: In step (1), when compound b is added, the temperature is -15 to 0°C; Or, in step (1), the reaction temperature is -15 to 0°C; Or, in step (2), the extraction solvent is selected from ethyl acetate, chloroform, dichloromethane, 2-methyltetrahydrofuran or toluene; Or, in step (2), the crystallization solvent is selected from any one of petroleum ether, n-heptane, methyl tert-butyl ether, ethyl acetate, toluene, or a mixture of two or more thereof.

7. The method according to claim 6, characterized in that: In step (2), the extraction solvent is selected from dichloromethane or chloroform; Alternatively, in step (2), the crystallization solvent is selected from methyl tert-butyl ether or a mixed solution of ethyl acetate and n-heptane.

8. The method according to claim 1, characterized in that: The preparation method of the compound b comprises the following steps: 1) adding part of compound d and a solvent to magnesium to initiate a reaction; 2) After initiating the reaction, the remaining compound d and a solvent mixed solution are added and reacted to obtain compound b.

9. The method according to claim 1, characterized in that: The mass ratio of the compound d to magnesium is 1:0.1-0.3; Or, the reaction temperature is 20-60°C; Alternatively, the reaction time is 0.5 to 3 hours.

10. The method according to claim 9, characterized in that: The mass ratio of the compound d to magnesium is 1:0.15-0.23; Or, the reaction temperature is 20-50°C; Alternatively, the reaction time is 1 to 2 hours.

11. The method according to claim 1, characterized in that: The solvent is selected from tetrahydrofuran and 2-methyltetrahydrofuran; The compound d is selected from phenyl bromide.

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