A method for synthesizing iron-promoted quinolopyrroline dione derivatives

Abstract

The application discloses a synthesis method of quinolino pyrrolo dione compounds. Heterocyclic compounds containing quinolino pyrrolo skeleton exhibit broad-spectrum pharmacological activities, including antimicrobial, analgesic, antiviral, anticonvulsant, anti-Alzheimer's disease and antitumor activities. A method for synthesizing quinolino pyrrolo dione derivatives by one-pot method through a cascade cyclization reaction under the promotion of iron from anthranilic acid hydrazide and maleimide is provided. The method has the advantages of simple operation, mild reaction condition, simple and easily available raw materials and the like.

Description

Technical fields:

[0001] This invention relates to the field of organic synthesis methodology, specifically to a method for synthesizing a class of quinolinopyrrole dione derivatives. Background technology:

[0002] Quinolinopyrrole dione derivatives are a special class of nitrogen-containing heterocyclic compounds. Because heterocyclic compounds containing quinoline and pyrrole skeletons exhibit broad-spectrum pharmacological activities, including antimicrobial, analgesic, antiviral, anticonvulsant, anti-Alzheimer's disease, and antitumor activities, they have received considerable attention in drug design.

[0003] Currently, some scholars have studied the synthesis methods of quinolinopyrrole dione derivatives. Most of these methods rely on multi-step reactions and start from substituted quinolines or substituted maleimide precursors. They still have some limitations, such as the use of noble metal catalysts, narrow substrate applicability, and large catalyst usage.

[0004] Therefore, it is of great significance to develop a more economical, efficient and environmentally friendly method for preparing quinolinopyrrole dione derivatives using readily available raw materials and catalysts. Summary of the Invention:

[0005] The technical problem solved by this invention is to propose a method for synthesizing a class of quinolinopyrrole dione derivatives. This method provides a new approach for synthesizing quinolinopyrrole dione derivatives by tandem cyclization of aminoanisidine and maleimide catalyzed by iron. Moreover, this method does not require a noble metal catalyst, has a short reaction time, mild reaction conditions, simple operation, broad reaction spectrum, and good functional group compatibility.

[0006] In a first aspect, this invention provides a method for synthesizing a class of quinolinopyrrole dione derivatives. The principle is as follows: aminoaniline anhydride is reacted with an iron catalyst to generate o-aminobenzaldehyde, which then undergoes a cyclization reaction with maleimide to generate quinolinopyrrole dione derivatives. The reaction formula is:

[0007]

[0008] Among them, R 1 It is one of the phenyl groups substituted with hydrogen, methyl, methoxy, or halogen; R 2 It is one of hydrogen, methyl, ethyl or benzyl; the general formula of aminoanisidine is shown in Formula 1, the general formula of maleimide is shown in Formula 2, and the general formula of quinolinopyrrole dione derivative is shown in Formula 3, wherein "[Fe]" is an iron-containing catalyst, "solvent" is a solvent, and "temp" is a temperature.

[0009] The steps of the method are as follows:

[0010] Step 1: Add ammoniacal anhydride, maleimide, iron catalyst, and acetonitrile as the reaction solvent to the reaction vessel.

[0011] Step 2: The reaction vessel is sealed and the reaction is carried out at a reaction temperature of 120°C for 3 hours.

[0012] Step 3: The substrate disappears as detected by TLC. After the reaction is complete, the reaction vessel is cooled to room temperature and then extracted with saturated brine to retain the organic phase. An equal volume of ethyl acetate is added to the aqueous phase for back-extraction to separate the organic and aqueous phases.

[0013] Step 4: After drying the organic phase with anhydrous sodium sulfate, filter, evaporate to dryness, and separate by column chromatography to obtain quinolinopyrrole dione derivatives, with the general formula shown in Formula 3.

[0014] Furthermore, the molar ratio of the feed materials of ammoniacal anhydride, maleimide, and metallic iron catalyst is 1:1:0 to 1.2.

[0015] Furthermore, R 1 To replace one of the aminoanisidines, wherein the substituents on the aminoanisidine are hydrogen, methyl, methoxy or halogen.

[0016] Furthermore, R 2 To replace one of the maleimides, wherein the substituents on the N-substituted maleimide are hydrogen, methyl, ethyl, propyl or benzyl.

[0017] Furthermore, the metallic iron catalyst is one of iron powder, ferrous iron, or ferric iron.

[0018] Furthermore, the reaction solvent is one of tetrahydrofuran, N,N-dimethylformamide, dimethyl sulfoxide, and acetonitrile.

[0019] Preferably, the metallic iron catalyst is FeSO4·7H2O; the reaction solvent is acetonitrile; and the reaction temperature is 120℃.

[0020] Secondly, a quinolinopyrrole dione derivative prepared according to the above preparation method can be applied in the pharmaceutical field.

[0021] The beneficial effects of this invention are:

[0022] 1. This invention proposes a one-pot tandem cyclization reaction method for synthesizing quinolinopyrrole dione compounds, providing a new approach for the preparation of such compounds.

[0023] 2. This method has the advantages of using inexpensive and readily available catalysts, readily available raw materials, simple operation, short reaction time, and high yield. Moreover, the functional groups of the substrates are highly compatible, and a series of quinolinopyrrole dione compounds can be synthesized, which has good potential application value. Attached image description:

[0024] Figure 1 This is a table showing the screening results of the reaction conditions in Example 1 of the present invention.

[0025] Figure 2 The compound 3a prepared in Example 2 of this invention 1 H-NMR nuclear magnetic resonance spectrum.

[0026] Figure 3 The compound 3a prepared in Example 2 of this invention 13 C-NMR nuclear magnetic resonance spectrum.

[0027] Figure 4 The compound 3b prepared in Example 3 of this invention 1 H-NMR nuclear magnetic resonance spectrum.

[0028] Figure 5 The compound 3b prepared in Example 3 of this invention 13 C-NMR nuclear magnetic resonance spectrum.

[0029] Figure 6 The compound 3c prepared in Example 4 of this invention 1 H-NMR nuclear magnetic resonance spectrum.

[0030] Figure 7 The compound 3c prepared in Example 4 of this invention 13 C-NMR nuclear magnetic resonance spectrum.

[0031] Figure 8 The compound 3d prepared in Example 5 of this invention 1 H-NMR nuclear magnetic resonance spectrum.

[0032] Figure 9 The compound 3d prepared in Example 5 of this invention 13 C-NMR nuclear magnetic resonance spectrum.

[0033] Figure 10 The compound 3e prepared in Example 6 of this invention 1 H-NMR nuclear magnetic resonance spectrum.

[0034] Figure 11 The compound 3e prepared in Example 6 of this invention 13 C-NMR nuclear magnetic resonance spectrum.

[0035] Figure 12 The compound 3f prepared in Example 7 of this invention 1 H-NMR nuclear magnetic resonance spectrum.

[0036] Figure 13 The compound 3f prepared in Example 7 of this invention 13 C-NMR nuclear magnetic resonance spectrum.

[0037] Figure 14 3g of the compound prepared in Example 8 of this invention 1 H-NMR nuclear magnetic resonance spectrum.

[0038] Figure 15 3g of the compound prepared in Example 8 of this invention 13 C-NMR nuclear magnetic resonance spectrum.

[0039] Figure 16 The compound 3h prepared in Example 9 of this invention 1 H-NMR nuclear magnetic resonance spectrum.

[0040] Figure 17 The compound 3h prepared in Example 9 of this invention 13 C-NMR nuclear magnetic resonance spectrum. Detailed implementation method:

[0041] The following embodiments are a further detailed description of the technical solutions of the present invention. The described embodiments are only some embodiments of the present invention, and not all embodiments.

[0042] Example 1:

[0043] In this embodiment, aminoanisidine 1a and N-methylmaleimide 2a were used as model substrates to screen different reaction conditions. Fe, FeSO4·7H2O, FeCl2, and FeCl3 were used as catalysts, and THF, DMF, DMSO, and acetonitrile were used as reaction solvents. The effects of catalyst type, solvent type, and temperature on the yield of the target product (2-methyl-1H-pyrrolo[3,4-b]quinoline-1,3(2H)-dione)3a were compared at temperatures of 60℃, 80℃, 100℃, 120℃, and 130℃.

[0044] The specific reaction conditions were as follows: 1.0 equivalent of compound aniline anhydride 1, 1.0 equivalent of compound maleimide 2, 1.2 equivalent of FeSO4·7H2O were mixed with 5 mL of MeCN and reacted at 120 °C for 3 hours.

[0045] The results are as follows Figure 1The table shows the screening results for the reaction conditions.

[0046] Example 2: The complete scheme for synthesizing compound 3a (2-methyl-1H-pyrrolo[3,4-b]quinoline-1,3(2H)-dione) is as follows:

[0047]

[0048] The specific synthetic steps for 2-methyl-1H-pyrrolo[3,4-b]quinoline-1,3(2H)-dione are as follows:

[0049] 1 mmol (119 mg) of aminoanisidine, 1 mmol (111 mg) of N-methylmaleimide, and 1.2 mmol (334 mg) of ferrous sulfate heptahydrate were weighed sequentially and mixed in a 35 mL pressure-resistant tube. 5 mL of acetonitrile was added as a solvent, and the mixture was reacted at 120 °C for 3 h under real-time monitoring until complete conversion. Then, 20 mL of saturated brine was added, and the mixture was extracted twice with 20 mL of ethyl acetate. The supernatant was collected, and the organic phase was dried over anhydrous Na₂SO₄. The solution was then concentrated by rotary evaporation to obtain the crude quinolinopyrrole dione product. The crude product was purified by silica gel column chromatography (elution: petroleum ether / ethyl acetate = 6:1) to obtain a white solid product (58 mg, yield 91%) with the general formula shown in Formula 3a. The NMR spectrum of this compound was... 1 H NMR, 13 CNMR image as follows Figure 2-3 The characterization data are as follows: mp 257-258℃; 1 H NMR (600MHz, CDCl3): δ8.66 (s, 1H), 8.43 (d, J = 8.4Hz, 1H), 8.07 (d, J = 8.4Hz, 1H), 7.95 (t, J = 7.8Hz, 1H), 7.77 (t, J = 7.8Hz, 1H), 3.34 (s, 3H). 13 C{ 1 H}NMR (150MHz, CDCl3): δ166.3,166.1,150.7,150.6,132.8,132.6,131.5,123.0,129.6,128.7,123.0,24.5.

[0050] Example 3: The complete scheme for synthesizing compound 3b (2,6-dimethyl-1H-pyrrolo[3,4-b]quinoline-1,3(2H)-dione) is as follows:

[0051]

[0052] The specific synthetic steps for 2,6-dimethyl-1H-pyrrolo[3,4-b]quinoline-1,3(2H)-dione are as follows:

[0053] 1 mmol (133 mg) of 6-methylaminoaniline anhydride, 1 mmol (111 mg) of N-methylmaleimide, and 1.2 mmol (334 mg) of ferrous sulfate heptahydrate were weighed sequentially and mixed in a 35 mL pressure-resistant tube. 5 mL of acetonitrile was added as a solvent, and the mixture was reacted at 120 °C for 3 h under real-time monitoring until complete conversion. Then, 20 mL of saturated brine was added, and the mixture was extracted twice with 20 mL of ethyl acetate. The supernatant was collected, and the organic phase was dried over anhydrous Na₂SO₄. The solution was then concentrated by rotary evaporation to obtain the crude quinolinopyrrole dione product. The crude product was purified by silica gel column chromatography (elution: petroleum ether / ethyl acetate = 6:1) to obtain a white solid product (61 mg, 90% yield) of the general formula shown in Formula 3b. The NMR spectrum of this compound was... 1 H NMR, 13 C NMR spectrum as shown Figure 4-5 The characterization data are as follows: mp 245-246℃; 1 H NMR (600MHz, CDCl3): δ8.57(s,1H),8.16(s,1H),7.93(d,J=8.4Hz,1H),7.59(d,J=7.8Hz,1H),3.32(s,3H),2.64(s,3H). 13 C{ 1 H}NMR (150MHz, CDCl3): δ166.4,166.2,150.8,150.6,143.9,132.1,131.7,130.4,129.5,126.6,122.1,24.4,22.1.

[0054] Example 4: The complete scheme for synthesizing compound 3c (7-methoxy-2-methyl-1H-pyrrolo[3,4-b]quinoline-1,3(2H)-dione) is as follows:

[0055]

[0056] The specific synthetic steps for 7-methoxy-2-methyl-1H-pyrrolo[3,4-b]quinoline-1,3(2H)-dione are as follows:

[0057] 1 mmol (149 mg) of 5-methoxyaminoaniline, 1 mmol (111 mg) of N-methylmaleimide, and 1.2 mmol (334 mg) of ferrous sulfate heptahydrate were weighed sequentially and mixed in a 35 mL pressure-resistant tube. 5 mL of acetonitrile was added as a solvent, and the mixture was reacted at 120 °C for 3 h under real-time monitoring until complete conversion. Then, 20 mL of saturated brine was added, and the mixture was extracted twice with 20 mL of ethyl acetate. The supernatant was collected, and the organic phase was dried over anhydrous Na₂SO₄. The solution was then concentrated by rotary evaporation to obtain the crude quinolinopyrrole dione product. The crude product was purified by silica gel column chromatography (elution: petroleum ether / ethyl acetate = 6:1) to obtain a white solid product (64 mg, yield 88%) with the general formula shown in Formula 3c. The NMR spectrum of this compound was... 1 HNMR, 13 C NMR spectrum as shown Figure 6-7 The characterization data are as follows: mp 240-241℃; 1 H NMR (600MHz, CDCl3): δ8.50(s,1H),8.28(d,J=9.0Hz,1H),7.56(d,J=9.0Hz,1H),7.27(s,1H),4.00(s,3H),3.32(s,3H). 13 C{ 1 H}NMR (150MHz, CDCl3): δ166.6,166.3,160.1,148.1,146.7,132.7,130.7,130.4,125.5,123.5,107.3,55.9,24.4.

[0058] Example 5: The complete scheme for synthesizing compound 3d (6-bromo-2-methyl-1H-pyrrolo[3,4-b]quinoline-1,3(2H)-dione) is as follows:

[0059]

[0060] The specific synthetic steps for 6-bromo-2-methyl-1H-pyrrolo[3,4-b]quinoline-1,3(2H)-dione are as follows:

[0061] 1 mmol (198 mg) of 6-bromoaminoaniline, 1 mmol (111 mg) of N-methylmaleimide, and 1.2 mmol (334 mg) of ferrous sulfate heptahydrate were weighed sequentially and mixed in a 35 mL pressure-resistant tube. 5 mL of acetonitrile was added as a solvent, and the mixture was reacted at 120 °C for 3 h under real-time monitoring until complete conversion. Then, 20 mL of saturated brine was added, and the mixture was extracted twice with 20 mL of ethyl acetate. The supernatant was collected, and the organic phase was dried over anhydrous Na₂SO₄. The solution was then concentrated by rotary evaporation to obtain the crude quinolinopyrrole dione product. The crude product was purified by silica gel column chromatography (elution: petroleum ether / ethyl acetate = 6:1) to obtain a white solid product (75 mg, yield 87%) with the general formula shown in Formula 3d. The NMR spectrum of this compound was... 1 H NMR, 13 CNMR image as follows Figure 8-9 The characterization data are as follows: mp 278-280℃; 1 H NMR (600MHz, CDCl3): δ8.64 (s, 1H), 8.59 (s, 1H), 7.94 (d, J = 9.0Hz, 1H), 7.86 (d, J = 8.4Hz, 1H), 3.35 (s, 3H). 13 C{ 1 H}NMR (150MHz, CDCl3): δ165.9,165.7,151.5,151.1,133.7,133.2,132.5,130.8,127.6,127.3,123.2,24.6.

[0062] Example 6: The complete scheme for synthesizing compound 3e (1H-pyrrolo[3,4-b]quinoline-1,3(2H)-dione) is as follows:

[0063]

[0064] The specific synthetic steps for 1H-pyrrolo[3,4-b]quinoline-1,3(2H)-dione are as follows:

[0065] 1 mmol (119 mg) of aminoanisidine, 1 mmol (97 mg) of maleimide, and 1.2 mmol (334 mg) of ferrous sulfate heptahydrate were weighed sequentially and mixed in a 35 mL pressure-resistant tube. 5 mL of acetonitrile was added as a solvent, and the mixture was reacted at 120 °C for 3 h under real-time monitoring until complete conversion. Then, 20 mL of saturated brine was added, and the mixture was extracted twice with 20 mL of ethyl acetate. The supernatant was collected, and the organic phase was dried over anhydrous Na₂SO₄. The solution was then concentrated by rotary evaporation to obtain the crude quinolinopyrrole dione product. The crude product was purified by silica gel column chromatography (elution: petroleum ether / ethyl acetate = 6:1) to obtain a white solid product (53 mg, yield 89%) with the general formula shown in Formula 3e. The NMR spectrum of this compound was... 1 H NMR, 13 C NMR spectrum as shown Figure 10-11 The characterization data are as follows: mp211-213℃. 1 H NMR (600MHz, DMSO-d6): δ11.97(s,1H),8.96(s,1H),8.32(t,J=7.8Hz,2H),8.03(t,J=7.8Hz,1H),7.85(t,J=7.8Hz,1H). 13 C{ 1 H}NMR (150MHz, DMSO-d6): δ167.3,167.0,151.7,149.8,132.7,132.6,130.4,129.1,128.5,124.2.

[0066] Example 7: The complete scheme for synthesizing compound 3f (2-ethyl-1H-pyrrolo[3,4-b]quinoline-1,3(2H)-dione) is as follows:

[0067]

[0068] The specific synthetic steps for 2-ethyl-1H-pyrrolo[3,4-b]quinoline-1,3(2H)-dione are as follows:

[0069] 1 mmol (119 mg) of aminoanisidine, 1 mmol (125 mg) of N-ethylmaleimide, and 1.2 mmol (334 mg) of ferrous sulfate heptahydrate were weighed sequentially and mixed in a 35 mL pressure-resistant tube. 5 mL of acetonitrile was added as a solvent, and the mixture was reacted at 120 °C for 3 h under real-time monitoring until complete conversion. Then, 20 mL of saturated brine was added, and the mixture was extracted twice with 20 mL of ethyl acetate. The supernatant was collected, and the organic phase was dried over anhydrous Na₂SO₄. The solution was then concentrated by rotary evaporation to obtain the crude quinolinopyrrole dione product. The crude product was purified by silica gel column chromatography (elution: petroleum ether / ethyl acetate = 6:1) to obtain a white solid product (60 mg, yield 88%) with the general formula shown in Formula 3f. The NMR spectrum of this compound was... 1 H NMR, 13 CNMR image as follows Figure 12-13 The characterization data are as follows: mp 185-187℃. 1 H NMR (600MHz, CDCl3): δ8.65 (s, 1H), 8.42 (d, J = 8.4Hz, 1H), 8.07 (d, J = 7.8Hz, 1H), 7.94 (t,J=7.8Hz,1H),7.78(t,J=7.8Hz,1H),3.91(q,J=7.2Hz,2H),1.36(t,J=7.2Hz,3H). 13 C{ 1 H}NMR (150MHz, CDCl3): δ166.1,165.8,150.7,150.6,132.7,132.5,131.4,129.9,129.5,128.7,123.0,33.5,13.8.

[0070] Example 8: The complete scheme for synthesizing 3g of compound (2-propyl-1H-pyrrolo[3,4-b]quinoline-1,3(2H)-dione) is as follows:

[0071]

[0072] The specific synthetic steps for 2-propyl-1H-pyrrolo[3,4-b]quinoline-1,3(2H)-dione are as follows:

[0073] 1 mmol (119 mg) of aminoanisidine, 1 mmol (139 mg) of N-propylmaleimide, and 1.2 mmol (334 mg) of ferrous sulfate heptahydrate were weighed sequentially and mixed in a 35 mL pressure-resistant tube. 5 mL of acetonitrile was added as a solvent, and the mixture was reacted at 120 °C for 3 h under real-time monitoring until complete conversion. Then, 20 mL of saturated brine was added, and the mixture was extracted twice with 20 mL of ethyl acetate. The supernatant was collected, and the organic phase was dried over anhydrous Na₂SO₄. The solution was then concentrated by rotary evaporation to obtain the crude quinolinopyrrole dione product. The crude product was purified by silica gel column chromatography (elution: petroleum ether / ethyl acetate = 6:1) to obtain a white solid product (63 mg, yield 87%) as shown in Formula 3g. The NMR spectrum of this compound was... 1 H NMR, 13 CNMR image as follows Figure 14-15 The characterization data are as follows: mp 173-175℃. 1 H NMR (600MHz, CDCl3): δ8.66(s,1H),8.43(d,J=8.4Hz,1H),8.07(d,J=8.4Hz,1H),7.95(t,J=7.2 Hz,1H),7.78(t,J=7.8Hz,1H),3.81(t,J=7.8Hz,2H),1.83-1.76(m,2H),1.01(t,J=7.8Hz,3H). 13 C{ 1 H}NMR (150MHz, CDCl3): δ166.3,166.1,150.8,150.6,132.7,132.5,131.5,129.9,129.5,128.8,123.0,40.2,21.8,11.3.

[0074] Example 9: The complete scheme for synthesizing compound 3h (2-benzyl-1H-pyrrolo[3,4-b]quinoline-1,3(2H)-dione) is as follows:

[0075]

[0076] The specific synthetic steps for 2-benzyl-1H-pyrrolo[3,4-b]quinoline-1,3(2H)-dione are as follows:

[0077] 1 mmol (119 mg) of aminoanisidine, 1 mmol (187 mg) of N-benzylmaleimide, and 1.2 mmol (334 mg) of ferrous sulfate heptahydrate were weighed sequentially and mixed in a 35 mL pressure-resistant tube. 5 mL of acetonitrile was added as a solvent, and the mixture was reacted at 120 °C for 3 h, monitored in real time, until complete conversion. Then, 20 mL of saturated brine was added, and the mixture was extracted twice with 20 mL of ethyl acetate. The supernatant was collected, and the organic phase was dried over anhydrous Na₂SO₄. The mixture was then concentrated by rotary evaporation to obtain the crude quinolinopyrrole dione product. The crude product was purified by silica gel column chromatography (elution: petroleum ether / ethyl acetate = 6:1) to obtain a white solid product (75 mg, yield 87%) with the general formula shown in Formula 3h. The NMR spectrum of this compound was... 1 H NMR, 13 CNMR image as follows Figure 16-17 The characterization data are as follows: mp 242-244℃. 1 H NMR (600MHz, CDCl3): δ8.64(s,1H),8.41(d,J=9.6Hz,1H),8.05(d,J=7.8Hz,1H),7.93(t,J=7.8Hz,1H), 7.75(t,J=7.8Hz,1H),7.50(d,J=7.2Hz,2H),7.34(t,J=7.8Hz,2H),7.29(d,J=7.8Hz,1H),5.00(s,2H). 13 C{ 1 H}NMR (150MHz, CDCl3): δ165.9,165.7,150.8,150.5,135.8,132.8,132.7,131.5,129.9,129.6,128.9,128.8,128.7,128.1,123.0,42.1.

[0078] The above embodiments are merely preferred technical solutions of the present invention and should not be considered as limitations on the present invention. The embodiments and features described in these embodiments can be arbitrarily combined without conflict. The scope of protection of the present invention should be limited to the technical solutions described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. A method for synthesizing a quinolinopyrrole dione derivative, wherein the reaction equation is as follows: in, R 1 It is one of the phenyl groups substituted with hydrogen, methyl, methoxy, or halogen; R 2 It is one of hydrogen, methyl, ethyl or benzyl; the general formula of aminoanisidine is shown in Formula 1, the general formula of maleimide is shown in Formula 2, and the general formula of quinolinopyrrole dione derivative is shown in Formula 3, wherein "[Fe]" is an iron-containing catalyst, "solvent" is a solvent, and "temp" is a temperature.

2. The method for synthesizing an iron-promoted quinolinopyrrole dione derivative according to claim 1, characterized in that, The steps of the method are as follows: Step 1: Add ammoniacal anhydride, maleimide, iron catalyst, and acetonitrile as the reaction solvent to the reaction vessel. Step 2: The reaction vessel is sealed and the reaction is carried out at a reaction temperature of 120°C for 3 hours. Step 3: The substrate disappears as detected by TLC. After the reaction is complete, the reaction vessel is cooled to room temperature and then extracted with saturated brine to retain the organic phase. An equal volume of ethyl acetate is added to the aqueous phase for back-extraction to separate the organic and aqueous phases. Step 4: After drying the organic phase with anhydrous sodium sulfate, filter, evaporate to dryness, and separate by column chromatography to obtain the quinolinopyrrole dione derivative.

3. A method for synthesizing a quinolinopyrrole dione derivative according to claim 1 or 2, characterized in that, The molar ratio of the feed materials of aminoanidine anhydride, maleimide, and metallic iron catalyst is 1:1:0 to 1.

2.

4. The method for synthesizing a quinolinopyrrole dione derivative according to claim 3, characterized in that, R 1 To replace one of the aminoanisidines, wherein the substituents on the aminoanisidine are hydrogen, methyl, methoxy or halogen.

5. The method for synthesizing a quinolinopyrrole dione derivative according to claim 3, characterized in that, R 2 To replace one of the maleimides, wherein the substituents on the N-substituted maleimide are hydrogen, methyl, ethyl, propyl or benzyl.

6. The method for synthesizing a quinolinopyrrole dione derivative according to claim 3, characterized in that, The metallic iron catalyst is one of iron powder, ferrous iron, or ferric iron.

7. The method for synthesizing a quinolinopyrrole dione derivative according to claim 3, characterized in that, The reaction solvent is one of tetrahydrofuran, N,N-dimethylformamide, dimethyl sulfoxide, and acetonitrile.

8. A method for synthesizing a quinolinopyrrole dione derivative according to any one of claims 4-7, characterized in that, The metallic iron catalyst is FeSO4·7H2O; the reaction solvent is acetonitrile; and the reaction temperature is 120℃.

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