Visible light-induced cyanoalkylation of 2-amino-1,4-naphthoquinone compounds at C-3 position

Abstract

The present invention relates to a novel method for cyanoalkylation of C-3 position of 2-amino-1,4-naphthoquinone compounds under visible light induction without the participation of photosensitizer, specifically, in an argon environment, under visible light irradiation, a substrate 2-amino-1,4-naphthoquinone compound is excited, and then a cyclobutanone oxime ester compound is subjected to single electron reduction, and then N-O bond cleavage occurs, β The desired 3-position cyanoalkylated 2-amino-1,4-naphthoquinone compounds are obtained by cleavage, free radical addition and deprotonation. The raw materials of this method are easily available, the steps are simple, no photosensitizer and oxidant are required, the reaction conditions are mild, and it is environmentally friendly. It is a new green method for synthesizing 2-amino-1,4-naphthoquinone derivatives.

Description

Technical Field

[0001] The invention belongs to the technical field of organic compound synthesis reaction and application, and relates to a method and application of C-3 cyanoalkylation of 2-amino-1,4-naphthoquinone compounds induced by visible light without the participation of photosensitizer. Background Art

[0002] 1,4-naphthoquinone is a natural pigment widely distributed in nature and has attracted extensive attention due to its important biological activity. Studies have found that when the 2-position of 1,4-naphthoquinone compounds contains an amino group or a substituted amino group, they also have a variety of biological activities, such as anti-cancer 1 , neuroprotection 2 , anti-malarial 3 , anti-inflammatory 4 and antibacterial 5 and other activities. Therefore, developing green and efficient methods to synthesize such compounds has always been one of the research directions in organic synthesis and medicinal chemistry. In the past few years, direct CH functionalization at the 3-position of 2-amino-1,4-naphthoquinone has become an effective method to obtain such compounds. For example, in 2017, Yang and colleagues reported a new method for trifluoromethylation of 2-amino-1,4-naphthoquinone using tert-butyl hydroperoxide (TBHP) as an oxidant and Zn(SO2CF3)2 as a trifluoromethylating agent. 6 Zhang’s group developed a copper-catalyzed three-component difunctionalization of aromatic olefins to obtain 1,4-naphthoquinone derivatives, in which α-bromocarboxylates served as radical precursors and 2-amino-1,4-naphthoquinone was used as a radical scavenging agent. 7 Subsequently, the same research group also reported a silver-catalyzed three-component difunctionalization of olefins, providing a synthetic method for obtaining CF3-functionalized alkyl-substituted quinone derivatives. 8 . Despite these achievements, there is still a need to develop novel and environmentally friendly methods to construct more complex 2-amino-1,4-naphthoquinone derivatives via direct C-3 functionalization. In the past decade, photoredox catalysis has become a hot area in organic chemistry due to its mild conditions, environmental friendliness and low-energy radiation. Visible light catalysis provides a more mild and effective method for the C-3 functionalization of 2-amino-1,4-naphthoquinone. However, there are only two reports on visible light-catalyzed C-3 alkylation of 2-amino-1,4-naphthoquinone. 9, and all of them are achieved by difunctionalizing olefins through free radical pathways, which have the problems of narrow application range and relatively single introduced functional groups. Therefore, it is of great significance to develop a simple and efficient alkylation method that can introduce other functional groups. Cyanoalkylation is a very useful reaction because cyano can be easily converted into other functional groups, such as aldehydes, esters, amides and carboxyls. At the same time, cyano is also a key group widely present in natural products and drugs. Therefore, the development of efficient and direct methods to prepare alkyl nitriles has aroused the interest of organic chemists. The present invention provides a new method for cyanoalkylation at the C-3 position of 2-amino-1,4-naphthoquinone compounds using cyclobutanone oxime ester as a cyanoalkyl radical precursor under visible light induction without the participation of a photosensitizer. Summary of the invention

[0003] The invention relates to a novel method for cyanoalkylation of 2-amino-1,4-naphthoquinone compounds at the C-3 position by using cyclobutanone oxime ester as a cyanoalkyl free radical precursor under visible light induction without the participation of a photosensitizer. The method comprises the following steps: using 2-amino-1,4-naphthoquinone compounds and cyclobutanone oxime ester compounds as raw materials in an argon environment, exciting the substrate 2-amino-1,4-naphthoquinone compounds by visible light irradiation, and then subjecting the cyclobutanone oxime ester compounds to single-electron reduction, followed by NO bond cleavage, β-cleavage, free radical addition and deprotonation, so as to obtain the desired 3-position cyanoalkylated 2-amino-1,4-naphthoquinone compounds.

[0004] The chemical reaction formula of the present invention is as follows:

[0005]

[0006] in:

[0007] R1 is hydrogen, halogen, C1-C5 alkyl, C1-C4 alkoxy, trifluoromethyl;

[0008] R2 is hydrogen, phenyl or benzyloxy.

[0009] The preparation steps are as follows:

[0010] 2-amino-1,4-naphthoquinone compounds, cyclobutanone oxime ester compounds and N,N-diisopropylethylamine were added to the sealed tube, and then the solvent was added and argon was purged three times. Then the sealed tube was placed in a 12 W photoreaction instrument and stirred at room temperature for 24 h. After the reaction was completed, the reaction solution was evaporated under reduced pressure to remove the solvent, and the residue was separated and purified by silica gel column chromatography to obtain the product.

[0011] In the above preparation method, the solvent is one of 1,4-dioxane, dichloroethane, and dimethyl sulfoxide; the visible light wavelength range is 390 nm-460 nm; the molar ratio of 2-amino-1,4-naphthoquinone compound: cyclobutanone oxime ester compound: N,N-diisopropylethylamine is 1: (1.5-2): (1-3).

[0012] The formation of cyanoalkyl group at C-3 position of 2-amino-1,4-naphthoquinone was confirmed by nuclear magnetic resonance hydrogen spectrum (1H NMR), carbon spectrum (13C NMR) and high-resolution mass spectrometry. The nuclear magnetic resonance spectra were measured by Varian IN0VA-400 nuclear magnetic resonance spectrometer, with tetramethylsilane (TMS) as internal standard (δ 0 ppm) and deuterated chloroform as solvent; the high-resolution mass spectra were measured by Agilent 1946B mass spectrometer. Specific implementation methods

[0013] The present invention is further described below in conjunction with specific embodiments, which is helpful for understanding the present invention, but it cannot be used to limit the scope of the present invention, and the scope of the present invention should be based on the scope of the claims.

[0014] Embodiment 1: Synthesis of compound 1

[0015]

[0016] 2-[(4-methylphenyl)amino]naphthoquinone-1,4-dione (26.3 mg, 0.10 mmol), cyclobutanone 0 - (4-(Trifluoromethyl)benzoyl)oxime (38.7 mg, 0.15 mmol) and N,N-diisopropylethylamine (38.8 mg, 0.30 mmol) were added to a 10 mL sealed tube, and 1 mL of 1,4-dioxane was added, and the argon gas was purged three times. Then the sealed tube was placed in a 12 W photoreaction apparatus and stirred at room temperature for 24 h. After the reaction was completed, the reaction solution was evaporated under reduced pressure to remove the solvent, and the residue was separated and purified by silica gel column chromatography to obtain 28.1 mg of a red solid with a yield of 85%.

[0017] The NMR data are characterized as 1 H NMR (400 MHz, Chloroform-d) δ 8.03 (ddd, J = 7.2, 5.4,1.4 Hz, 2H), 7.67 (td, J = 7.6, 1.4 Hz, 1H), 7.59 (td, J= 7.5, 1.3 Hz, 1H), 7.37(s, 1H), 7.12 (s, 1H), 7.10 (s, 1H), 6.96 (s, 1H), 6.94 (s, 1H), 2.35 – 2.27(m, 2H), 2.30 (s, 3H), 1.91 (t, J = 7.5 Hz, 2H), 1.51 (dd, J = 8.4, 6.8 Hz, 2H). 13 C NMR (101 MHz, Chloroform-d) 1H182.6, 181.6, 142.2, 135.5, 135.0, 133.7,132.2, 131.5, 129.2, 128.8, 125.5, 125.3, 123.3, 118.3, 117.0, 23.3, 22.6,20.0, 15.7. HRMS (ESI): m / z calcd. 21 H 18 N2O2H + : 331.1441, measured value: 331.1443.

[0018] Example 2: Synthesis of Compound 2

[0019]

[0020] 2-Phenylamino-naphthoquinone-1,4-dione (24.9 mg, 0.10 mmol), cyclobutanone 0 - (4-(Trifluoromethyl)benzoyl)oxime (38.7 mg, 0.15 mmol) and N,N-diisopropylethylamine (38.8 mg, 0.30 mmol) were added to a 10 mL sealed tube, and 1 mL of 1,4-dioxane was added, and the argon gas was purged three times. Then the sealed tube was placed in a 12 W photoreaction apparatus and stirred at room temperature for 24 h. After the reaction was completed, the reaction solution was evaporated under reduced pressure to remove the solvent, and the residue was separated and purified by silica gel column chromatography to obtain 25.0 mg of a red solid with a yield of 79%.

[0021] The NMR data are characterized as 1 H NMR (400 MHz, Chloroform-d) δ 8.11 (ddd, J = 7.5, 4.8,1.3 Hz, 2H), 7.75 (td, J = 7.6, 1.4 Hz, 1H), 7.67 (td, J= 7.6, 1.4 Hz, 1H), 7.48(s, 1H), 7.39 (t, J = 7.7 Hz, 2H), 7.23 (t, J = 7.8 Hz, 1H), 7.13 (s, 1H), 7.11(s, 1H), 2.42 (dd, J = 8.6, 6.7 Hz, 2H), 1.98 (t, J = 7.5 Hz, 2H), 1.63 – 1.58(m, 2H). 13 C NMR (101 MHz, Chloroform-d) δ 182.7, 181.6, 142.0, 138.2, 133.7,132.1, 131.6, 129.2, 128.2, 125.5, 125.3, 124.8, 122.9, 118.2, 117.9, 23.6,22.5, 15.7. HRMS (ESI): m / z calcd. C 20 H 16 N2O2H + : 317.1285, measured value: 317.1286.

[0022] Embodiment 3: Synthesis of compound 3

[0023]

[0024] 2-[(3-chloro-phenyl)amino]naphthoquinone-1,4-dione (28.3 mg, 0.10 mmol), cyclobutanone 0-(4-(trifluoromethyl)benzoyl)oxime (51.6 mg, 0.20 mmol) and N,N-diisopropylethylamine (38.8 mg, 0.30 mmol) were added to a 10 mL sealed tube, and 1 mL of 1,4-dioxane was added, and argon was purged three times. Then the sealed tube was placed in a 12 W photoreaction apparatus and stirred at room temperature for 24 h. After the reaction was completed, the reaction solution was evaporated under reduced pressure to remove the solvent, and the residue was separated and purified by silica gel column chromatography to obtain 27.0 mg of a red solid with a yield of 77%.

[0025] The NMR data are characterized by 1H NMR (400 MHz, Chloroform-d) δ 8.15 – 8.07 (m, 2H),7.76 (td, J = 7.6, 1.5 Hz, 1H), 7.69 (td, J = 7.5, 1.4 Hz, 1H), 7.38 (s, 1H),7.31 (t, J = 8.0 Hz, 1H), 7.17 (d, J = 8.1 Hz, 1H), 7.06 (t, J = 2.0 Hz, 1H),6.98 (d, J = 8.0 Hz, 1H), 2.46 (dd, J = 8.7, 6.5 Hz, 2H), 2.10 (t, J = 7.3, 1.4 Hz, 2H), 1.69 (p, J = 7.5 Hz, 2H). 13C NMR (101 MHz, Chloroform-d) δ 182.8,181.3, 141.5, 139.8, 134.0, 133.8, 132.0, 131.8, 129.3, 129.2, 125.6, 125.4,124.3, 121.9, 120.0, 120.0, 118.1, 24.1, 22.2, 15.8. HRMS (ESI): m / z calcd for C20H15ClN2O2H+: 351.0895, found: 351.0899.

[0026] Embodiment 4: Synthesis of compound 4

[0027]

[0028] 2-[(4-methoxy-phenyl)amino]naphthoquinone-1,4-dione (27.9 mg, 0.10 mmol), cyclobutanone 0 -(4-(Trifluoromethyl)benzoyl)oxime (51.6 mg, 0.20 mmol) and N,N-diisopropylethylamine (38.8 mg, 0.30 mmol) were added to a 10 mL sealed tube, and 1 mL of 1,4-dioxane was added, and the argon gas was purged three times. Then the sealed tube was placed in a 12W photoreaction apparatus and stirred at room temperature for 24 h. After the reaction was completed, the reaction solution was evaporated under reduced pressure to remove the solvent, and the residue was separated and purified by silica gel column chromatography to obtain 27.3 mg of a red solid with a yield of 79%.

[0029] The NMR data are characterized as 1 H NMR (400 MHz, Chloroform-d) δ 8.10 (ddd, J= 7.6, 4.0,1.4 Hz, 2H), 7.74 (td, J = 7.6, 1.4 Hz, 1H), 7.65 (td, J = 7.5, 1.3 Hz, 1H), 7.43(s, 1H), 7.11 (s, 1H), 7.09 (s, 1H), 6.93 (s, 1H), 6.90 (s, 1H), 3.84 (s,3H), 2.40 – 2.32 (m, 2H), 1.99(t, J = 7.5 Hz, 2H), 1.57 (tt, J = 9.5, 6.7 Hz,2H). 13 C NMR (101 MHz, Chloroform-d) δ 183.6, 182.6, 158.1, 143.6, 134.7,133.2, 132.4, 131.8, 130.2, 126.5, 126.5, 126.3, 119.4, 117.1, 114.5, 55.6,24.0, 23.8, 16.8. HRMS (ESI): m / z calcd. 21 H 18 N2O3H + : 347.1390, measured value: 347.1393.

[0030] Embodiment 5: Synthesis of compound 5

[0031]

[0032] 2-[(4-trifluoromethyl-phenyl)amino]naphthoquinone-1,4-dione (31.7 mg, 0.10 mmol), cyclobutanone 0 -(4-(Trifluoromethyl)benzoyl)oxime (51.6 mg, 0.20 mmol) and N,N-diisopropylethylamine (38.8 mg, 0.30 mmol) were added to a 10 mL sealed tube, and then 1 mL of 1,4-dioxane was added, and the argon gas was purged three times. Then the sealed tube was placed in a 12W photoreaction apparatus and stirred at room temperature for 24 h. After the reaction was completed, the reaction solution was evaporated under reduced pressure to remove the solvent, and the residue was separated and purified by silica gel column chromatography to obtain 30.7 mg of a red solid with a yield of 80%.

[0033] The NMR data are characterized as 1 H NMR (400 MHz, Chloroform-d) δ 8.12 (td, J= 7.5, 1.3Hz, 2H), 7.78 (td, J = 7.5, 1.5 Hz, 1H), 7.71 (td, J = 7.5, 1.4 Hz, 1H), 7.62 (s,1H), 7.60 (s, 1H), 7.44 (s, 1H), 7.11 (s, 1H), 7.09 (s, 1H), 2.50 (dd, J = 8.2,6.6 Hz, 2H), 2.12 (t, J = 7.3 Hz, 2H), 1.71 (p, J = 7.4 Hz, 2H). 13 C NMR (101 MHz, Chloroform-d) δ 183.9, 182.3, 142.8, 142.1, 134.9, 133.1, 132.9, 130.3,126.7, 126.6 (q, J = 4.1 Hz), 126.2, 125.3, 123.0, 122.6, 121.4, 119.1, 25.6,23.4, 16.8. 19 F NMR (376 MHz, Chloroform-d) δ -62.07. HRMS (ESI): m / z calcd. C 21 H 15 F3N2O2H + : 385.1158, measured value: 385.1161.

[0034] Embodiment 6: Synthesis of compound 6

[0035]

[0036] 2-[(4-tert-butyl-phenyl)amino]naphthoquinone-1,4-dione (30.5 mg, 0.10 mmol), cyclobutanone 0 -(4-(Trifluoromethyl)benzoyl)oxime (51.6 mg, 0.20 mmol) and N,N-diisopropylethylamine (38.8 mg, 0.30 mmol) were added to a 10 mL sealed tube, and 1 mL of 1,4-dioxane was added, and the argon gas was purged three times. Then the sealed tube was placed in a 12W photoreaction apparatus and stirred at room temperature for 24 h. After the reaction was completed, the reaction solution was evaporated under reduced pressure to remove the solvent, and the residue was separated and purified by silica gel column chromatography to obtain 25.7 mg of a red solid with a yield of 69%.

[0037] The NMR data are characterized as 1 H NMR (400 MHz, Chloroform-d) δ 8.10 (dd, J = 7.5, 1.5Hz, 2H), 7.77 – 7.71 (m, 1H), 7.66 (td, J = 7.5, 1.4 Hz, 1H), 7.56 (s, 1H),7.48 (dd, J = 7.7, 1.9 Hz, 1H), 7.29 – 7.19 (m, 2H), 7.03 (dd, J = 7.5, 1.9Hz, 1H), 2.15 (t, J = 7.9 Hz, 2H), 1.93 (t, J = 7.6 Hz, 2H), 1.63 (d, J =15.5 Hz, 2H), 1.45 (s, 9H). 13 C NMR (101 MHz, Chloroform-d) δ 184.0, 182.8,145.1, 143.2, 138.2, 134.8, 133.4, 132.4, 130.1, 127.5, 127.1, 127.1, 126.6,126.4, 126.4, 119.2, 116.6, 35.3, 30.5, 25.2, 23.9, 17.1. HRMS (ESI): m / z calcd. for C 24 H 24 N2O2H + : 373.1911, measured value: 373.1914.

[0038] Embodiment 7: Synthesis of compound 7

[0039]

[0040] 2-[(4-methylphenyl)amino]naphthoquinone-1,4-dione (26.3 mg, 0.10 mmol), 3-phenylcyclobutane-1-one O - (4-(Trifluoromethyl)benzoyl)oxime (50.0 mg, 0.15 mmol) and N,N-diisopropylethylamine (38.8 mg, 0.30 mmol) were added to a 10 mL sealed tube, and 1 mL of 1,4-dioxane was added, and the argon gas was purged three times. Then the sealed tube was placed in a 12 W photoreaction apparatus and stirred at room temperature for 24 h. After the reaction was completed, the reaction solution was evaporated under reduced pressure to remove the solvent, and the residue was separated and purified by silica gel column chromatography to obtain 31.7 mg of a red solid with a yield of 78%.

[0041] The NMR data are characterized as1 H NMR (400 MHz, Chloroform-d) δ 8.09 (dd, J = 7.7, 1.3Hz, 1H), 8.06 (dd, J = 7.7, 1.3 Hz, 1H), 7.73 (td, J = 7.6, 1.4 Hz, 1H), 7.64(td, J = 7.5, 1.3 Hz, 1H), 7.45 (s, 1H), 7.18 (d, J = 2.6 Hz, 1H), 7.16 (d, J = 1.9Hz, 3H), 6.98 (s, 1H), 6.96 (s, 1H), 6.90 (d, J = 2.2 Hz, 1H), 6.88 (d, J = 1.6Hz, 1H), 3.00 (p, J = 7.5 Hz, 1H), 2.86 (dd, J = 14.2, 7.7 Hz, 1H), 2.77 (dd, J =14.1, 7.7 Hz, 1H), 2.38 (d, J = 1.2 Hz, 1H), 2.36 (s, 1H), 2.36 (s, 3H). 13 C NMR (101 MHz, Chloroform-d) δ 183.7, 182.5, 143.1, 141.1, 136.0, 135.6, 134.8,133.0, 132.5, 130.1, 129.8, 128.5, 127.3, 127.0, 126.6, 126.3, 123.6, 118.5,116.8, 40.5, 31.4, 23.7, 21.0. HRMS (ESI): m / z calcd. for C 27 H 22 N2O2H + : 407.1754, measured value: 407.1758.

[0042] Embodiment 8: Synthesis of compound 8

[0043]

[0044] 2-[(4-methylphenyl)amino]naphthoquinone-1,4-dione (26.3 mg, 0.10 mmol), 3-(benzyloxy)cyclobutane-1-one O - (4-(Trifluoromethyl)benzoyl)oxime (54.5 mg, 0.15 mmol) and N,N-diisopropylethylamine (38.8 mg, 0.30 mmol) were added to a 10 mL sealed tube, and then 1 mL of 1,4-dioxane was added, and the argon gas was purged three times. Then the sealed tube was placed in a 12 W photoreaction apparatus and stirred at room temperature for 24 h. After the reaction was completed, the reaction solution was evaporated under reduced pressure to remove the solvent, and the residue was separated and purified by silica gel column chromatography to obtain 27.0 mg of a red solid with a yield of 62%.

[0045] The NMR data are characterized as 1 H NMR (400 MHz, Chloroform-d) δ 8.09 (t, J = 7.7 Hz,2H), 7.75 (td, J = 7.5, 1.4 Hz, 1H), 7.67 (td, J = 7.5, 1.4 Hz, 1H), 7.52 (s,1H), 7.20 (d, J = 1.9 Hz, 3H), 7.15 (s, 1H), 7.13 (s, 1H), 6.88 (s, 1H), 6.86(s, 1H), 4.45 (d, J = 11.5 Hz, 1H), 4.27 (d, J = 11.5 Hz, 1H), 3.75 (p, J = 6.0 Hz,1H), 2.91 (dd, J = 14.1, 6.7 Hz, 1H), 2.64 (dd, J = 14.1, 6.1 Hz, 1H), 2.34 (s, 3H), 2.32 (s, 1H), 2.31 (s, 1H). 13C NMR (101 MHz, Chloroform-d) δ 183.6,182.2, 143.8, 137.4, 136.5, 135.4, 134.6, 133.0, 132.6, 130.5, 129.8, 128.4,128.0, 127.9, 126.5, 126.4, 123.4, 117.6, 116.3, 73.9, 72.1, 30.6, 23.3,21.0. HRMS (ESI): m / z calcd. for C 28 H 24 N2O3H + : 437.1860, measured value: 437.1864.

[0046] References

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[0048] 2.Josey, B. J.; Inks, E. S.; Wen, X.; Chou, C. J., Structure–activity relationship study of vitamin K derivatives yields highly potentneuroprotective agents. J. Med. Chem. 2013, 56, 1007-1022.

[0049] 3.Kapadia, GJ; Azuine, MA; Balasubramanian , V. ; Sridhar, R.,Aminophthoquinones--a novel class of compounds with potent antimalarialactivity against Plasmodium falciparum. Pharmacol. Res. 2001, 43, 363–367.

[0050] 4.De Luna Martins, D.; Borges , AA ; NOTHING, IT IS; Faria, JV;Hoelz, LVB; de Souza , H. ; Bello , ML ; Boechat , N. ; Ferreira, VF;Faria, RX, P2X7 receptor inhibition by 2-amino-3-aryl-1,4-naphthoquinones.Bioorg. Chem. Rev. 2020, 104,

[0051] 5. Ravichandiran, P.; Sheet, S.; Premnath, D.; Kim, AR; Yoo, DJ, 1,4-Naphthoquinone analogues: potent antibacterial agents and mode ofaction evaluation. Molecules 2019 , 24 , 1437 .

[0052] 6.Li, J.; Zhang, X.; Xiang, H.; Tong, L.; Feng, F.; Xie, H.; Ding,J.; Yang, C., C-H Trifluoromethylation of 2-Substituted / UnsubstitutedAminonaphthoquinones at Room Temperature with Bench-Stable (CF(3)SO(2))(2)Zn:Synthesis and Antiproliferative Evaluation. J. Org. Chem. 2017, 82, 6795-6800.

[0053] 7.Shangguan, Y.; Yang, F.; Deng, H.; Liu, H.; Liu, Z.; Zhuang, W.;Qiao, C.; Wang, A.; Xiao, Y.; Zhang, C., Copper-Catalyzed Three-ComponentDifunctionalization of Aromatic Alkenes with 2-Amino-1,4-naphthoquinones andalpha-Bromocarboxylates. J. Org. Chem. 2019, 84, 10649-10657.

[0054] 8.Wang, Q.; Wang, B.; Deng, H.; Shangguan, Y.; Lin, Y.; Zhang, Y.;Zhang, Z.; Xiao, Y.; Guo, H.; Zhang, C., Silver-Catalyzed Three-ComponentDifunctionalization of Alkenes via Radical Pathways: Access to CF(3)-Functionalized Alkyl-Substituted 1,4-Naphthoquinone Derivatives. J. Org.Chem. 2019, 84, 1006-1014.

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Claims

1. A method for visible light-induced cyanoalkylation of 2-amino-1,4-naphthoquinone compounds at C-3, characterized in that In an argon atmosphere, the raw materials 2-amino-1,4-naphthoquinone compounds, cyclobutanone oxime ester compounds and N,N -Diisopropylethylamine is added to the solvent. Under visible light irradiation, the substrate 2-amino-1,4-naphthoquinone compounds are excited, and then the cyclobutanone oxime ester compounds are reduced by a single electron, followed by the breakage of the NO bond. β -fragmentation and free radical addition reaction to obtain 2-amino-1,4-naphthoquinone compounds with 3-cyanoalkylation. The general reaction formula is as follows: , in: R1 is hydrogen, halogen, C1-C5 alkyl, C1-C4 alkoxy, trifluoromethyl; R2 is hydrogen, phenyl or benzyloxy.

2. The method according to claim 1, wherein the preparation steps are as follows: 2-amino-1,4-naphthoquinone compounds, cyclobutanone oxime ester compounds and N,N -Diisopropylethylamine was added to the sealed tube, and then the solvent was added, and the tube was ventilated with argon for three times; then the sealed tube was placed in a 12 W photoreaction apparatus and stirred at room temperature for 24 h; after the reaction was completed, the reaction solution was evaporated under reduced pressure to remove the solvent, and the residue was separated and purified by silica gel column chromatography to obtain the product.

3. The method according to claim 2, characterized in that The solvent is one of 1,4-dioxane, ethylene dichloride and dimethyl sulfoxide.

4. The method according to claim 2, characterized in that The wavelength range of visible light is 390 nm-460 nm.

5. The method according to claim 2, characterized in that 2-Amino-1,4-naphthoquinone compounds: Cyclobutanone oxime ester compounds: N,N -The molar ratio of diisopropylethylamine is 1: (1.5~2): (1~3).

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