A kind of synthetic method of 4-nitrobenzophenone compound

Abstract

The invention discloses a kind of synthesis method of 4-nitrobenzophenone, the method is that α-(4-oxime-2,5-cyclohexadiene-1-yl) benzyl cyanide compounds are added to an organic solvent, cooled to 0 DEG C, and then nitrogen oxides, iodine and alkaline reagents are added in sequence; Feeding is complete, and reacts to completion at 40-120 DEG C; The reaction solution is cooled to room temperature, and 10% sodium bisulfite aqueous solution is added to remove unreacted iodine; Water is added to dilute the reaction solution, and then extracted 3 times with dichloromethane; Combine organic phases, wash with saturated common salt water, dry with anhydrous sodium sulfate, and recycle organic solvent by vacuum distillation; Residue is recrystallized with toluene, and 4-nitrobenzophenone compounds are obtained after vacuum drying. The nitrogen oxide used in the present invention is a commercially available reagent with higher activity; Reaction raw materials are easily prepared, and are obtained by condensation of benzyl cyanide and nitrobenzene compounds under the action of alkaline reagents; The present invention also has the advantages of simple synthesis process, shorter route, environmental friendliness, better safety, higher product yield and purity, and easy industrial production.

Description

Technical Field

[0001] The invention relates to a method for synthesizing 4-nitrobenzophenone compounds, and belongs to the technical field of medicine and chemical industry. Background Art

[0002] 4-Nitrobenzophenone compounds are important organic synthesis intermediates, which are widely used in the fields of medicine, pesticides, fine chemicals, etc. They can be used to synthesize anti-inflammatory drugs, antibacterial drugs, anti-rheumatic drugs, analgesics, insecticides, herbicides, thermal recording materials, dyes, coatings, ultraviolet absorbers, cross-linking agents, etc. Therefore, the research on the synthesis process of 4-nitrobenzophenone compounds is of great significance.

[0003] At present, the synthesis routes of 4-nitrobenzophenone compounds are mainly the following:

[0004] The first method is to catalyze aluminum chloride, 4-nitrobenzoyl chloride and benzene in a solvent-free condition, microwave irradiation for 10 minutes, and obtain 4-nitrobenzophenone compounds through acylation reaction with a yield of 95%. This reaction has a high yield and a fast speed, but requires a microwave irradiation device and is not suitable for industrial production. The reaction formula is shown in Formula 1:

[0005]

[0006] The second is at KCC-1 / GMSI / VB 12 Under the catalysis of nanoparticles, 4-nitroiodobenzene and phenylboric acid reacted in anisole solution under a 1MPa carbon monoxide gas atmosphere for 1 hour, and 4-nitrobenzophenone was obtained through Suzuki-Miyaura coupling reaction with a yield of 98%. 12 The nanoparticle preparation process is cumbersome and not suitable for industrial production. The reaction formula is shown in Formula 2:

[0007]

[0008] The third method is to react p-nitrobenzoyl chloride with phenylboronic acid in acetonitrile solution under the catalysis of thiazoline-functionalized periodic mesoporous organosilica-supported palladium nanoparticles (Pd-TMPO). sp 2 -C sp 2 The bond formation reaction is carried out to obtain 4-nitrobenzophenone with a yield of 99%. Although the reaction yield of this method is high, the catalyst preparation process is relatively complicated, expensive, and not suitable for industrial production. The reaction formula is shown in Formula 3:

[0009]

[0010] The fourth method is to perform photocatalytic oxidation of secondary alcohols by catalyzing 4-nitrophenyl-phenylmethanol in 1 atmosphere of oxygen or air under 5 mol% sodium trifluoromethanesulfonate and irradiating with LED (400-405 nm) for 12 hours at room temperature, with a yield of 94%. Since the raw materials are difficult to prepare and the reaction time is long, it is not suitable for industrial production. The reaction formula is shown in Formula 4:

[0011]

[0012] The fifth method is to react 4-chlorobenzophenone with sodium nitrite in a tert-butyl alcohol solution at 130°C for 24 hours under the catalysis of 0.5 mol% tris(dibenzylideneacetone)dipalladium, 1.2 mol% diphenylphosphine ligand t-Bu (t-BuBrettPhos), and 5 mol% tris(3,6-dioxaheptyl)amine (TDA), and obtain 4-nitrobenzophenone through substitution reaction with a yield of 98%. Since the catalyst and phosphine ligand are expensive and the reaction temperature is high, it is not suitable for industrial production. The reaction formula is shown in Formula 5:

[0013]

[0014] The sixth method is to react 4-nitrofluorobenzene with benzaldehyde in N,N-dimethylformamide solution under the catalysis of N-azacarbene catalyst 1,3-dimethylimidazolium iodide under the protection of argon, under the action of strong base sodium hydride, and react at -15°C for 10 minutes, then heat to -5°C, and then heat to 0°C, undergoing an aromatic acylation reaction to obtain 4-nitrobenzophenone with a yield of 81%. This reaction requires argon protection, the reaction temperature is low, and the steps after the reaction are cumbersome, so it is not suitable for industrial production. The reaction formula is shown in Formula 6:

[0015]

[0016] The seventh is that 4-nitrobromobenzene and sodium tetraphenylborate are reacted at 130°C for 10 hours in N,N-dimethylformamide solution under the catalysis of 2 mol% supported divalent palladium catalyst (MCM-41-2P-Pd(II)) under 1 atmosphere of carbon monoxide gas atmosphere. 4-nitrobenzophenone is obtained by post-reaction treatment with a yield of 84%. The reaction yield is good, but the reaction conditions are relatively harsh, requiring the use of expensive reagents such as palladium and sodium tetraphenylborate, as well as flammable and explosive carbon monoxide gas, and is not suitable for industrial production. The reaction formula is shown in Formula 7:

[0017] Summary of the invention

[0018] The purpose of the present invention is to solve the shortcomings of the prior art and provide a method for synthesizing 4-nitrobenzophenone compounds.

[0019] The method uses α-(4-oxime-2,5-cyclohexadien-1-yl)benzeneacetonitrile compounds as raw materials, reacts in an organic solvent in the presence of nitrogen oxides, iodine and an alkaline reagent to prepare 4-nitrobenzophenone compounds.

[0020] The technical solution adopted by the present invention is:

[0021] A method for synthesizing 4-nitrobenzophenone compounds, the method comprising: adding an α-(4-oxime-2,5-cyclohexadien-1-yl)benzyl cyanide compound to an organic solvent, cooling to 0°C, and then sequentially adding nitrogen oxide, iodine and an alkaline reagent; after the addition is completed, reacting at 40-120°C until completion; cooling the reaction solution to room temperature, adding a 10% sodium bisulfite aqueous solution to remove unreacted iodine; adding water to dilute the reaction solution, and then extracting with dichloromethane for 3 times; combining the organic phases, washing with saturated brine, drying with anhydrous sodium sulfate, and recovering the organic solvent by reduced pressure distillation; the residue is recrystallized with toluene, and vacuum dried to obtain a 4-nitrobenzophenone compound; the reaction formula is shown in Formula 8:

[0022]

[0023] The α-(4-oxime-2,5-cyclohexadiene-1-yl)benzene acetonitrile compound R 1 , R 2 The substituents are one or two of hydrogen, halogen, C1-4 alkyl, and C1-4 alkoxy.

[0024] The nitrogen oxide is one of pyridine-N-oxide, 4-methylpyridine-N-oxide, 4-phenylpyridine-N-oxide, 2,6-dimethylpyridine-N-oxide, 2,2,6,6-tetramethylpiperidine-1-oxyl free radical, 4-oxo-2,2,6,6-tetramethylpiperidine-1-oxyl free radical, and 4-hydroxy-2,2,6,6-tetramethylpiperidine oxide.

[0025] The alkaline reagent is one of sodium carbonate, potassium carbonate, sodium bicarbonate, sodium hydroxide or potassium hydroxide.

[0026] The organic solvent is one of dichloromethane, chloroform, benzene, toluene, acetonitrile, N,N-dimethylformamide and dimethyl sulfoxide.

[0027] The molar ratio of the α-(4-oxime-2,5-cyclohexadiene-1-yl)benzene acetonitrile compound, iodine element, nitrogen oxide and alkaline reagent is 1.0:1.0-2.0:0.02-0.5:1.0-3.0.

[0028] The mass ratio of the organic solvent to the α-(4-oxime-2,5-cyclohexadiene-1-yl)benzene acetonitrile compound is 5 to 25:1.

[0029] Compared with the prior art, the invention has the following beneficial effects: the nitrogen oxide used in the invention is a commercially available reagent with high activity; the reaction raw material is easy to prepare and is obtained by condensing benzyl cyanide and nitrobenzene compounds under the action of an alkaline reagent; the invention also has the advantages of simple synthesis process, short route, environmental friendliness, good safety, high product yield and purity, easy industrial production, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The nuclear magnetic hydrogen spectrum of (4-nitrophenyl) (4-methoxyphenyl) ketone of the present invention is

[0031] Figure 2 The infrared spectrum of (4-nitrophenyl) (4-methoxyphenyl) ketone of the present invention is

[0032] Figure 3 The nuclear magnetic hydrogen spectrum of (3-methoxy-4-nitrophenyl) (3,4-dimethoxyphenyl) ketone of the present invention is

[0033] Figure 4 The infrared spectrum of (3-methoxy-4-nitrophenyl) (3,4-dimethoxyphenyl) ketone of the present invention is DETAILED DESCRIPTION

[0034] The present invention is further described below in conjunction with specific embodiments, but the protection scope of the present invention is not limited thereto:

[0035] Example 1

[0036] Add 11.11g (0.05mol) α-(4-oxime-2,5-cyclohexadiene-1-yl) benzyl cyanide and 110mL chloroform into a 500mL three-necked flask, cool to 0°C, and add 3.44g (0.02mol) 4-hydroxy-2,2,6,6-tetramethylpiperidin oxide, 20.30g (0.08mol) iodine, and 2.81g (0.05mol) potassium hydroxide in sequence. After the addition is completed, heat to 50°C and react for 8h. The reaction solution is cooled to room temperature, and 80mL of 10% sodium bisulfite solution is added and stirred for 15min. Add 100mL of water to dilute the reaction solution, and then extract with dichloromethane (3×50mL). Combine the organic phases, wash with saturated brine, dry with anhydrous sodium sulfate, and recover the organic solvent by vacuum distillation. The residue is recrystallized from toluene and vacuum dried to obtain 10.70g of 4-nitrobenzophenone. The yield was 94.2% and the HPLC purity was 98.5%.

[0037] Example 2

[0038] Add 12.83g (0.05mol) α-(4-oxime-2-chloro-2,5-cyclohexadien-1-yl) benzyl cyanide and 120mL acetonitrile to a 500mL three-necked flask, cool to 0°C, and add 0.10g (0.001mol) pyridine-N-oxide, 12.69g (0.05mol) iodine, and 5.30g (0.05mol) sodium carbonate in sequence. After the addition is completed, heat to 60°C and react for 10h. The reaction solution is cooled to room temperature, 55mL of 10% sodium bisulfite solution is added, and stirring is continued for 15min. Add 100mL of water to dilute the reaction solution, and then extract with dichloromethane (3×50mL). Combine the organic phases, wash with saturated brine, dry with anhydrous sodium sulfate, and recover the organic solvent by vacuum distillation. The residue is recrystallized from toluene and vacuum dried to obtain 12.25g of (2-chloro-4-nitrophenyl) benzophenone. The yield was 93.6% and the HPLC purity was 97.7%.

[0039] Example 3

[0040] Add 15.76g (0.05mol) α-(4-oxime-3-bromo-2,5-cyclohexadien-1-yl)-4'-methylbenzeneacetonitrile and 130mL chloroform into a 500mL three-necked flask, cool to 0°C, and add 0.55g (0.005mol) 4-methylpyridine-N-oxide, 15.86g (0.0625mol) iodine, and 13.82g (0.1mol) potassium carbonate in sequence. After the addition is completed, heat to 55°C and react for 12h. Cool the reaction solution to room temperature, add 65mL of 10% sodium bisulfite solution, and continue stirring for 15min. Add 100mL of water to dilute the reaction solution, and then extract with dichloromethane (3×50mL). Combine the organic phases, wash with saturated brine, dry over anhydrous sodium sulfate, and recover the organic solvent by distillation under reduced pressure. The residue was recrystallized from toluene and dried in vacuo to give 15.55 g of (4-methoxyphenyl)(3-bromo-4-nitrophenyl)methanone with a yield of 92.5% and a HPLC purity of 97.1%.

[0041] Example 4

[0042] Add 14.02g (0.05mol) α-(4-oxime-3-ethyl-2,5-cyclohexadien-1-yl)-3'-methoxybenzeneacetonitrile and 110mL dichloromethane to a 500mL three-necked flask, cool to 0°C, and add 2.14g (0.0125mol) 4-phenylpyridine-N-oxide, 25.38g (0.1mol) iodine, and 12.60g (0.15mol) sodium bicarbonate in sequence. After the addition is completed, heat to 40°C and react for 14.5h. Cool the reaction solution to room temperature, add 105mL of 10% sodium bisulfite solution, and continue stirring for 15min. Add 100mL of water to dilute the reaction solution, and then extract with dichloromethane (3×50mL). Combine the organic phases, wash with saturated brine, dry over anhydrous sodium sulfate, and recover the organic solvent by distillation under reduced pressure. The residue was recrystallized from toluene and dried in vacuo to give 13.08 g of (3-ethyl-4-nitrophenyl)(3-methoxyphenyl)methanone with a yield of 91.7% and a HPLC purity of 98.2%.

[0043] Example 5

[0044] Add 13.31g (0.05mol) α-(4-oxime-3-ethoxy-2,5-cyclohexadien-1-yl) benzene acetonitrile and 230mL benzene into a 500mL three-necked flask, cool to 0°C, and add 3.10g (0.025mol) 2,6-dimethylpyridine-N-oxide, 19.04g (0.075mol) iodine, and 6.00g (0.15mol) sodium hydroxide in sequence. After the addition is completed, heat to 65°C and react for 13h. Cool the reaction solution to room temperature, add 80mL of 10% sodium bisulfite solution, and continue stirring for 15min. Add 100mL of water to dilute the reaction solution, and then extract with dichloromethane (3×50mL). Combine the organic phases, wash with saturated brine, dry over anhydrous sodium sulfate, and recover the organic solvent by distillation under reduced pressure. The residue was recrystallized from toluene and dried in vacuo to give 12.91 g of (3-ethoxy-4-nitrophenyl)benzophenone with a yield of 95.2% and a HPLC purity of 97.8%.

[0045] Example 6

[0046] Add 14.17g (0.05mol) α-(4-oxime-3-propyl-2,5-cyclohexadien-1-yl)-2'-fluorobenzeneacetonitrile and 330mL toluene into a 500mL three-necked flask, cool to 0°C, and add 2.34g (0.015mol) 2,2,6,6-tetramethylpiperidin-1-oxyl free radical, 22.21g (0.0875mol) iodine, and 5.61g (0.1mol) potassium hydroxide in sequence. After the addition is completed, heat to 50°C and react for 12.5h. Cool the reaction solution to room temperature, add 90mL of 10% sodium bisulfite solution, and continue stirring for 15min. Add 100mL of water to dilute the reaction solution, and then extract with dichloromethane (3×50mL). Combine the organic phases, wash with saturated brine, dry over anhydrous sodium sulfate, and recover the organic solvent by distillation under reduced pressure. The residue was recrystallized from toluene and dried in vacuo to give 13.06 g of (3-propyl-4-nitrophenyl)(2-fluorophenyl)methanone with a yield of 90.9% and a HPLC purity of 98.4%.

[0047] Example 7

[0048] Add 14.34g (0.05mol) α-(4-oxime-3-chloro-2,5-cyclohexadien-1-yl)-2'-methoxybenzeneacetonitrile and 350mL N,N-dimethylformamide into a 500mL three-necked flask, cool to 0°C, and add 3.40g (0.02mol) 4-oxo-2,2,6,6-tetramethylpiperidin-1-oxyl free radical, 17.77g (0.07mol) iodine, and 5.30g (0.05mol) sodium carbonate in sequence. After the addition is completed, heat to 75°C and react for 14h. Cool the reaction solution to room temperature, add 75mL of 10% sodium bisulfite solution, and continue stirring for 15min. Add 100mL of water to dilute the reaction solution, and then extract with dichloromethane (3×50mL). The organic phases were combined, washed with saturated brine, then washed with 350 mL of water, dried over anhydrous sodium sulfate, and distilled under reduced pressure to recover the organic solvent. The residue was recrystallized from toluene and dried under vacuum to obtain 13.77 g of (2-methoxyphenyl)(3-chloro-4-nitrophenyl)methanone. The yield was 94.4% and the HPLC purity was 97.9%.

[0049] Example 8

[0050] Add 18.11g (0.05mol) α-(4-oxime-3-methyl-2,5-cyclohexadien-1-yl)-2'-iodobenzeneacetonitrile and 300mL dimethyl sulfoxide to a 500mL three-necked flask, cool to 0°C, and add 0.43g (0.0025mol) 4-hydroxy-2,2,6,6-tetramethylpiperidinoxide, 22.84g (0.09mol) iodine, and 13.82g (0.1mol) potassium carbonate in sequence. After the addition is completed, heat to 100°C and react for 15h. Cool the reaction solution to room temperature, add 95mL of 10% sodium bisulfite solution, and continue stirring for 15min. Add 100mL of water to dilute the reaction solution, and then extract with dichloromethane (3×50mL). Combine the organic phases, wash with saturated brine, wash with 300mL of water, dry with anhydrous sodium sulfate, and recover the organic solvent by vacuum distillation. The residue was recrystallized from toluene and dried in vacuo to give 16.39 g of (3-methyl-4-nitrophenyl)(2-iodophenyl)methanone with a yield of 89.3% and a HPLC purity of 96.4%.

[0051] Example 9

[0052] Add 13.97g (0.05mol) α-(4-oxime-2,5-cyclohexadiene-1-yl)-3'-butylbenzeneacetonitrile and 55mL dichloromethane to a 500mL three-necked flask, cool to 0°C, and add 0.86g (0.005mol) 4-phenylpyridine-N-oxide, 20.30g (0.08mol) iodine, and 8.40g (0.1mol) sodium bicarbonate in sequence. After the addition is completed, heat to 40°C and react for 11.5h. Cool the reaction solution to room temperature, add 85mL of 10% sodium bisulfite solution, and continue stirring for 15min. Add 100mL of water to dilute the reaction solution, and then extract with dichloromethane (3×50mL). Combine the organic phases, wash with saturated brine, dry over anhydrous sodium sulfate, and recover the organic solvent by distillation under reduced pressure. The residue was recrystallized from toluene and dried in vacuo to give 12.54 g of (3-butylphenyl)(4-nitrophenyl)methanone with a yield of 88.5% and a HPLC purity of 97.3%.

[0053] Example 10

[0054] Add 12.61g (0.05mol) α-(4-oxime-2,5-cyclohexadiene-1-yl)-4'-methoxybenzeneacetonitrile and 330mL N,N-dimethylformamide to a 500mL three-necked flask, cool to 0°C, and add 2.34g (0.015mol) 2,2,6,6-tetramethylpiperidin-1-oxyl free radical, 25.38g (0.1mol) iodine, and 2.00g (0.05mol) sodium hydroxide in sequence. After the addition is completed, heat to 90°C and react for 11h. Cool the reaction solution to room temperature, add 105mL of 10% sodium bisulfite solution, and continue stirring for 15min. Add 100mL of water to dilute the reaction solution, and then extract with dichloromethane (3×50mL). Combine the organic phases, wash with saturated brine, wash with 340mL of water, dry over anhydrous sodium sulfate, and recover the organic solvent by distillation under reduced pressure. The residue was recrystallized from toluene and dried in vacuo to give 12.44 g of (4-nitrophenyl)(4-methoxyphenyl)methanone with a yield of 96.7% and a HPLC purity of 97.0%. 1 HNMR (400MHz, CDCl3) δ: 8.34 (d, J = 8.8Hz, 2H, ArH), 7.89 (d, J = 8.4Hz, 2H, ArH), 7.82 (d, J = 8.8Hz, 2H, ArH), 7.00 (d, J = 8.4Hz, 2H, ArH), 3.91 (s, 3H, OCH3) ppm. IR(KBr):ν=3103,2976,2841,1641,1591,1512,1354,1319,1265,935,870,851cm -1 .

[0055] Embodiment 11

[0056] Add 15.62g (0.05mol) α-(4-oxime-3-methoxy-2,5-cyclohexadiene-1-yl)-3',4'-dimethoxybenzeneacetonitrile and 120mL acetonitrile to a 500mL three-necked flask, cool to 0°C, and add 2.38g (0.025mol) pyridine-N-oxide, 12.69g (0.05mol) iodine, and 8.42g (0.15mol) potassium hydroxide in sequence. After the addition is completed, heat to 120°C and react for 10.5h. Cool the reaction solution to room temperature, add 55mL of 10% sodium bisulfite solution, and continue stirring for 15min. Add 100mL of water to dilute the reaction solution, and then extract with dichloromethane (3×50mL). Combine the organic phases, wash with saturated brine, dry over anhydrous sodium sulfate, and recover the organic solvent by distillation under reduced pressure. The residue was recrystallized from toluene and dried in vacuo to obtain 14.72 g of (3-methoxy-4-nitrophenyl)(3,4-dimethoxyphenyl)methanone with a yield of 92.8% and a HPLC purity of 97.5%. 1H NMR(400MHz, CDCl3)δ:7.88(d,J=8.2Hz,1H,ArH),7.49(d,J=8.2Hz,2H,ArH),7.40-7.32(m,2H , ArH), 6.93 (d, J = 8.4Hz, 1H, ArH), 4.01 (s, 3H, OCH3), 3.99 (s, 3H, OCH3), 3.96 (s, 3H, OCH3) ppm. IR(KBr):ν=3101,3047,2985,2839,1659,1585,1520,1273,1184,1122,1022cm -1 .

[0057] The HPLC analysis conditions of 4-nitrobenzophenone compounds are as follows: high performance liquid chromatograph (Agilent 1200 Series); chromatographic column model LlChrospher 60RP-select B (5 μL); mobile phase 10 mmol, acetonitrile-water (volume ratio 60:40); flow rate 1.5 mL / min, injection volume 10 μL; detector is ultraviolet photometry detector, wavelength 254 nm; sample is dissolved and diluted with acetonitrile (0.02 mg / mL) and then injected.

[0058] The specific embodiments described in the present invention are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the attached claims.

[0059] Although the present invention has been described in detail and some specific embodiments have been cited, it is obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present invention.

Claims

1. A method for synthesizing 4-nitrobenzophenone compounds, comprising adding an α-(4-oximino-2,5-cyclohexadien-1-yl)benzyl cyanide compound to an organic solvent, cooling the mixture to 0°C, and then sequentially adding nitrogen oxide, iodine and an alkaline agent; reacting the mixture at 40 to 120°C until the mixture is finished; cooling the reaction solution to room temperature, adding a 10% sodium bisulfite aqueous solution to remove unreacted iodine; diluting the reaction solution with water, and then extracting the mixture with dichloromethane for three times; combining the organic phases, washing the mixture with saturated brine, drying the mixture with anhydrous sodium sulfate, and recovering the organic solvent by distillation under reduced pressure; and recrystallizing the residue with toluene and drying the mixture under vacuum to obtain a 4-nitrobenzophenone compound; R 1 , R 2 The substituent is one or two of hydrogen, halogen, C1-4 alkyl, and C1-4 alkoxy; the nitrogen oxide is one of pyridine-N-oxide, 4-methylpyridine-N-oxide, 4-phenylpyridine-N-oxide, 2,6-dimethylpyridine-N-oxide, 2,2,6,6-tetramethylpiperidin-1-oxyl free radical, 4-oxo-2,2,6,6-tetramethylpiperidin-1-oxyl free radical, and 4-hydroxy-2,2,6,6-tetramethylpiperidin-oxide; the reaction equation is:

2. A method for synthesizing 4-nitrobenzophenone compounds according to claim 1, characterized in that: The alkaline reagent is one of sodium carbonate, potassium carbonate, sodium bicarbonate, sodium hydroxide or potassium hydroxide.

3. A method for synthesizing 4-nitrobenzophenone compounds according to claim 1, characterized in that: The organic solvent is one of dichloromethane, chloroform, benzene, toluene, acetonitrile, N,N-dimethylformamide and dimethyl sulfoxide.

4. A method for synthesizing 4-nitrobenzophenone compounds according to claim 1, characterized in that: The molar ratio of the α-(4-oxime-2,5-cyclohexadiene-1-yl)benzene acetonitrile compound, iodine element, nitrogen oxide and alkaline reagent is 1.0:1.0-2.0:0.02-0.5:1.0-3.

0.

5. A method for synthesizing 4-nitrobenzophenone compounds according to claim 1, characterized in that: The mass ratio of the organic solvent to the α-(4-oxime-2,5-cyclohexadiene-1-yl)benzene acetonitrile compound is 5 to 25:1.

Images