阅读说明：本技术 一种光催化合成多取代喹啉类化合物的方法 (Method for synthesizing polysubstituted quinoline compound through photocatalysis ) 是由 罗再刚 徐雪梅 李蕊 韦丹丹 刘帅 李忠 于 2021-06-29 设计创作，主要内容包括：本发明公开一种光催化制备多取代喹啉类化合物的方法,包括以下步骤：将Ν-甲基联苯-2-胺类化合物与丁炔二羧酸酯类化合物溶于二甲亚砜溶剂中,再加入过氧化二异丙苯,在蓝光照射条件下室温反应24h,反应结束后,柱层析分离,得到多取代喹啉类化合物。本方法采用Ν-甲基联苯-2-胺类化合物与丁炔二羧酸酯类化合物为原料,在过氧化二叔丁基存在和蓝光照射下发生加成环化反应。该反应体系温和,操作简单,收率高。多取代喹啉类化合物具有广泛的用途,也可作为有用的合成中间体。(The invention discloses a method for preparing polysubstituted quinoline compounds by photocatalysis, which comprises the following steps: dissolving the N-methylbiphenyl-2-amine compound and the butynedicarboxylate compound in a dimethyl sulfoxide solvent, adding dicumyl peroxide, reacting at room temperature for 24 hours under the condition of blue light irradiation, and after the reaction is finished, performing column chromatography separation to obtain the polysubstituted quinoline compound. The method adopts an N-methylbiphenyl-2-amine compound and a butynedicarboxylic acid ester compound as raw materials, and performs addition cyclization reaction in the presence of di-tert-butyl peroxide and under the irradiation of blue light. The reaction system is mild, the operation is simple, and the yield is high. The polysubstituted quinoline compounds have wide application and can also be used as useful synthetic intermediates.)

1. a method for synthesizing polysubstituted quinoline compounds by photocatalysis is characterized by comprising the following steps: dissolving an N-methylbiphenyl-2-amine compound 1 and a butynedicarboxylate compound 2 in a reaction solvent, adding an oxidant, reacting at room temperature for 24 hours under the irradiation of blue light (blue LED), and after the reaction is finished, performing column chromatography separation to obtain an addition cyclization product quinoline compound 3, wherein the reaction formula is as follows:

wherein R is¹Represented by H, or fluorine, chlorine, bromine, methyl, ethyl, propyl, butyl, isopropyl, tert-butyl, methoxy, ethoxy, these substituents being substitutable in the ortho-, meta-, para-and multi-positions of the phenyl ring; r²Represented by H, or by fluorine, chlorine, bromine, methyl, ethyl, propyl, butyl, isopropyl, tert-butyl, methoxy, ethoxy, phenyl, these substituents being substitutable in the ortho-, meta-, para-and multi-positions of the phenyl ring; r³Expressed as methyl, ethyl, propyl, butyl, isopropyl, tert-butyl, phenyl; using a blue LED lamp as a light source; the oxidant is di-tert-butyl peroxide, or one of benzoyl peroxide, dicumyl peroxide and tert-butyl hydroperoxide; the reaction solvent is acetonitrile or one of dimethyl sulfoxide, 1, 4-dioxane, chlorobenzene, toluene, fluorobenzene and tetrahydrofuran.

2. The method for preparing the polysubstituted quinoline compound 3 through photocatalysis according to claim 1, characterized in that a 24W blue LED lamp is preferably used as the reaction light source.

3. The method for preparing the polysubstituted quinoline compound 3 through photocatalysis according to claim 1, wherein dicumyl peroxide is preferably used as the reaction oxidant.

4. The method for preparing the polysubstituted quinoline compound 3 through photocatalysis according to claim 1, wherein dimethyl sulfoxide is preferably used as the reaction solvent.

5. The method for preparing the polysubstituted quinoline compound 3 through photocatalysis according to claim 1, wherein the mass ratio of the N-methylbiphenyl-2-amine compound 1, the butynedicarboxylate compound 2 and the oxidant is 1:2: 2.

Technical Field

The invention belongs to the field of organic synthetic chemistry, and relates to a method for preparing a polysubstituted quinoline compound through photocatalysis, in particular to a method for preparing the polysubstituted quinoline compound through an addition cyclization reaction of an N-methylbiphenyl-2-amine compound and a butynedicarboxylate compound in the presence of an oxidant and under the irradiation of blue light (blue LED).

Background

Quinoline compounds have wide biological activity, are important synthetic intermediates in the field of organic synthesis, and have wide application in other industrial fields, so the synthetic method thereof is concerned. The traditional quinoline compound synthesis methods such as Skraup reaction, Combes reaction, Conrad-Limbach reaction, Doebner-VonMuller reaction, Gould-Jacobs reaction, Friedlander reaction, Povavov reaction, Pfitzinger reaction and the like are harsh in reaction conditions, more in side reactions and serious in pollution. Recently, numerous documents report methods for preparing quinolines by photocatalytic reaction, such as: (1) in 2016, Zhang et al reported a method for producing quinoline compounds by a visible light catalytic oxidative dehydrogenation coupling/aromatization tandem reaction of glycine ester and unactivated olefin (J.Org.chem.,2016,81,12433-12442.), but the reaction requires the synergistic action of copper salt and a photocatalyst to react, and the reaction system is complex. (2) In 2018, Jiang et al also reported that a plurality of alpha-branched 2-vinylpyridine and 2-vinylquinoline compounds respectively undergo redox, free radical conjugate addition and protonation with glycine by using double concerted catalysis of visible light-induced chiral phosphoric acid and DPZ photosensitizer, and finally obtain a plurality of chiral 3- (2-pyridine/quinoline) -3-substituted amine compounds (J.Am.chem.Soc., 140, 6083-one 6087.) with high yield. In the reaction, the reaction can be carried out only by the synergistic action of the cobalt salt, the additive and the photocatalyst, the reaction system is complex, the separation is difficult, the substrate applicability is poor, and the large-scale popularization and application are difficult.

Therefore, there remains a need to develop and optimize new methods for preparing polysubstituted quinolines.

Disclosure of Invention

The invention mainly aims to provide a method for preparing a polysubstituted quinoline compound aiming at the defects of the prior art.

The method comprises the steps of taking an N-methylbiphenyl-2-amine compound and a butynedicarboxylic acid ester compound as raw materials, reacting for 24 hours at room temperature in the presence of an oxidant in a dimethyl sulfoxide solution and under the irradiation of blue light (blue LED), and carrying out addition cyclization reaction to generate the polysubstituted quinoline compound. The reaction method has the advantages of cheap and easily-obtained raw materials, mild reaction conditions, no need of using a photosensitizer and transition metal, simple post-treatment process, wide product extension range and good industrialization potential.

The synthetic route principle of the invention is as follows:

wherein R is¹Represented by H, or fluorine, chlorine, bromine, methyl, ethyl, propyl, butyl, isopropyl, tert-butyl, methoxy, ethoxy, these substituents being substitutable in the ortho-, meta-, para-and multi-positions of the phenyl ring; r²Represented by H, or by fluorine, chlorine, bromine, methyl, ethyl, propyl, butyl, isopropyl, tert-butyl, methoxy, ethoxy, phenyl, these substituents being substitutable in the ortho-, meta-, para-and multi-positions of the phenyl ring; r³Expressed as methyl, ethyl, propyl, butyl, isopropyl, tert-butyl, phenyl. The light source used is a blue LED lamp. The oxidant is di-tert-butyl peroxide, or one of benzoyl peroxide, dicumyl peroxide and tert-butyl hydroperoxide. The reaction solvent is acetonitrile or one of dimethyl sulfoxide, 1, 4-dioxane, chlorobenzene, toluene, fluorobenzene and tetrahydrofuran.

In order to achieve the purpose, the invention adopts the following technical scheme for synthesizing the compound:

adding the N-methylbiphenyl-2-amine compound 1, the butynedicarboxylate compound 2, the oxidant and the reaction solvent into the reaction tube in sequence, and placing the reaction tube under the irradiation of blue light (blue LED) for reacting at room temperature for 24 hours after the addition. And after the reaction is finished, performing flash column chromatography separation to obtain the polysubstituted quinoline compound 3.

The reaction light source in the method is a 24-watt blue light LED lamp.

Dicumyl peroxide is preferably used as the reaction oxidant in the oxidizing agent in the method.

The organic solvent in the method is acetonitrile, or one of dimethyl sulfoxide, 1, 4-dioxane, chlorobenzene, toluene, fluorobenzene and tetrahydrofuran, wherein dimethyl sulfoxide is preferably used as the reaction solvent.

The mass ratio of the N-methylbiphenyl-2-amine compound 1, the butynedicarboxylate compound 2 and the oxidant in the method is 1:2: 2.

Compared with the route of the prior art, the invention has the following advantages:

(1) the method has the advantages of wide substrate application range, mild reaction conditions, simple post-treatment process and high product yield.

(3) The method is simple and efficient, is superior to the synthesis method reported in the existing literature, does not need a photosensitizer or transition metal, and is used for preparing the polysubstituted quinoline compound through an addition cyclization reaction of the N-methylbiphenyl-2-amine compound and the butynedicarboxylate compound under the catalysis of blue light.

Detailed Description

The invention is described in further detail with reference to specific examples, but the scope of the invention as claimed is not limited thereto.

Example 1 was carried out: 0.018g (0.1mmol) of N-methylbiphenyl-2-amine 1a, 0.028g (0.2mmol) of methyl butynedicarboxylate 2a, 0.030g (0.2mmol) of di-tert-butyl peroxide and 2mL of DMSO are sequentially added into a 10mL thick-walled pressure-resistant tube, and the reaction is magnetically stirred for 24 hours under the irradiation of a 24W blue LED, and the reaction progress is monitored by TLC. After the reaction is finished, column chromatography separation is carried out to obtain (petroleum ether (60-90 ℃)/ethyl acetate (15:1)]This gave 8-phenyl-3, 4-dicarboxylic acid methyl ester quinoline 3a as a white solid, 22mg, yield 68%.¹H NMR(500Hz,CDCl₃)(δ,ppm)9.46(s,1H),7.88(dd,J＝7.1,1.2Hz,1H),7.84(dd,J＝ 8.4,1.2Hz,1H),7.72(dd,J＝8.3,7.3Hz,1H),7.67-7.64(m,2H),7.51(t,J＝7.4Hz,2H),7.46- 7.42(m,1H),4.13(s,3H),4.01(s,3H).¹³C NMR(125MHz,CDCl₃Ppm)167.57, 164.85,149.36, 147.47,142.55,141.49,138.60,132.85,130.62,128.65,128.08,127.79,125.45,123.57,118.72, 53.20,52.92 the reaction principle for example 1 is carried out as follows:

example 2 was carried out: 0.018g (0.1mmol) of N-methylbiphenyl-2-amine 1a, 0.028g (0.2mmol) of methyl butynedicarboxylate 2a, 0.054g (0.2mmol) of dicumyl peroxide and 2mL of DMSO are sequentially added into a 10mL thick-walled pressure-resistant tube, and the reaction is magnetically stirred for 24 hours under the irradiation of a 24W blue LED, and the reaction progress is monitored by TLC. After the reaction is finished, column chromatography separation is carried out to obtain (petroleum ether (60-90 ℃)/ethyl acetate (15: 1)) 8-phenyl-3, 4-methyl diformate quinoline 3a, wherein the white solid is 24mg, and the yield is 75%. Example 2 the reaction principle is as follows:

example 3 of implementation: 0.018g (0.1mmol) of N-methylbiphenyl-2-amine 1a, 0.028g (0.2mmol) of methyl butynedicarboxylate 2a, 0.048g (0.2mmol) of benzoyl peroxide and 2mL of DMSO are sequentially added into a 10mL thick-walled pressure-resistant tube, and the reaction is magnetically stirred for 24 hours under the irradiation of a 24W blue LED, and the reaction progress is monitored by TLC. After the reaction was completed, column chromatography was performed [ petroleum ether (60-90 ℃ C.)/ethyl acetate (15:1) ], to obtain 8-phenyl-3, 4-dicarboxylic acid methylester quinoline 3a as a white solid (11 mg) with a yield of 35%. Example 3 the reaction principle is as follows:

example 4 of implementation: 0.018g (0.1mmol) of N-methylbiphenyl-2-amine 1a, 0.028g (0.2mmol) of methyl butynedicarboxylate 2a, 0.054g (0.2mmol) of potassium persulfate and 2mL of DMSO are sequentially added into a 10mL thick-walled pressure-resistant tube, and the reaction is magnetically stirred for 24 hours under the irradiation of a 24W blue LED, and the reaction progress is monitored by TLC. After the reaction is finished, column chromatography separation is carried out to obtain (petroleum ether (60-90 ℃)/ethyl acetate (15: 1)) 8-phenyl-3, 4-methyl diformate quinoline 3a, 21mg of white solid is obtained, and the yield is 64%. Example 4 the reaction principle is as follows:

example 5 was carried out: 0.018g (0.1mmol) of N-methylbiphenyl-2-amine 1a, 0.028g (0.2mmol) of methyl butynedicarboxylate 2a, 0.054g (0.2mmol) of dicumyl peroxide and 2mL of tetrahydrofuran are sequentially added into a 10mL thick-walled pressure-resistant tube, and the reaction is magnetically stirred for 24 hours under the irradiation of a 24W blue LED, and the reaction progress is monitored by TLC. After the reaction is finished, column chromatography separation is carried out to obtain (petroleum ether (60-90 ℃)/ethyl acetate (15: 1)) 8-phenyl-3, 4-methyl diformate quinoline 3a, 22mg of white solid is obtained, and the yield is 67%. Example 5 the reaction principle is as follows:

example 6 of implementation: 0.018g (0.1mmol) of N-methylbiphenyl-2-amine 1a, 0.028g (0.2mmol) of methyl butynedicarboxylate 2a, 0.054g (0.2mmol) of dicumyl peroxide and 2mL of acetonitrile are sequentially added into a 10mL thick-walled pressure-resistant tube, and the reaction is magnetically stirred for 24 hours under the irradiation of 24W blue LED, and the reaction progress is monitored by TLC. After the reaction was completed, column chromatography was performed [ petroleum ether (60-90 ℃ C.)/ethyl acetate (15:1) ], to obtain 8-phenyl-3, 4-dicarboxylic acid methylester quinoline 3a as a white solid (18 mg) with a yield of 57%. Example 6 the reaction principle is as follows:

example 7 was carried out: 0.018g (0.1mmol) of N-methylbiphenyl-2-amine 1a, 0.028g (0.2mmol) of methyl butynedicarboxylate 2a, 0.054g (0.2mmol) of dicumyl peroxide and 2mL of toluene are sequentially added into a 10mL thick-walled pressure-resistant tube, and the mixture is magnetically stirred for reaction for 24 hours under the irradiation of a 24W blue LED, and the reaction progress is monitored by TLC. After the reaction, column chromatography separation [ petroleum ether (60-90 ℃)/ethyl acetate (15:1) ] was performed to obtain 8-phenyl-3, 4-dicarboxylic acid methyl ester quinoline 3a as a white solid, 13mg, with a yield of 40%. Example 7 the reaction principle is as follows:

example 8 was carried out: 0.020g (0.1mmol) of N-methyl-4' -methylbiphenyl-2-amine 1b, 0.028g (0.2mmol) of methyl butynedicarboxylate 2a, 0.054g (0.2mmol) of dicumyl peroxide, 2mL of DMSOAdding into 10ml thick-wall pressure-resistant tube, reacting under 24W blue LED for 24h, and monitoring the reaction process by TLC. After the reaction is finished, column chromatography separation is carried out to obtain (petroleum ether (60-90 ℃)/ethyl acetate (15:1)]To give 8- (4' -methyl) phenyl-3, 4-dicarboxylic acid methyl ester quinoline 3b as a white solid (17 mg) with a yield of 52%.¹H NMR(400MHz,CDCl₃,ppm)δ9.45(s,1H),7.86(dd,J＝7.1,1.4Hz, 1H),7.81(dd,J＝8.4,1.4Hz,1H),7.71(dd,J＝8.4,7.1Hz,1H),7.55(d,J＝8.0Hz,2H),7.32(d, J＝7.9Hz,2H),4.13(s,3H),4.00(s,3H),2.44(s,3H).¹³C NMR(100MHz,CDCl₃Ppm) delta 167.63,164.91,149.29,147.60,142.55,141.53,137.63,135.69,135.34,132.67,130.50,128.86, 128.12, 125.20, 123.60, 53.18, 52.90, 21.28 the reaction principle for carrying out example 8 is as follows:

example 9 was carried out: 0.022g (0.1mmol) of N-methyl-4' chlorobiphenyl-2-amine 1c, 0.028g (0.2mmol) of methyl butynedicarboxylate 2a, 0.054g (0.2mmol) of dicumyl peroxide and 2mL of DMSO are sequentially added into a 10mL thick-walled pressure tube, and the reaction is magnetically stirred for 24 hours under the irradiation of a 24W blue LED, and the reaction progress is monitored by TLC. After the reaction is finished, column chromatography separation is carried out to obtain (petroleum ether (60-90 ℃)/ethyl acetate (15:1)]To give quinoline 3c, methyl 8- (4' -chloro) phenyl-3, 4-dicarboxylate as a white solid (15 mg, 43% yield).¹H NMR(400MHz,CDCl₃,ppm)δ9.46(s,1H),7.89-7.81(m,2H),7.73(dd,J＝ 8.4,7.2Hz,1H),7.45(ddd,J＝24.9,17.1,10.1Hz,3H),7.17-7.11(m,1H),4.13(s,3H),4.01(s, 3H).¹³C NMR(100MHz,CDCl₃Ppm) delta 167.49,164.78,163.66,149.55,147.20,142.64,140.68, 140.60,132.87,129.56,129.47,128.10,126.30,126.28,125.99,123.60,118.89,117.87,117.65, 114.81,114.60,53.27,52.99 the reaction principle for carrying out example 9 is as follows:

EXAMPLES 10: 0.020g (0.1mmol) of N-methyl-4' -fluorobiphenyl-2-amine 1d, 0.028g (0.2mmol) of methyl butynedicarboxylate 2a, 0.054g (0.2mmol) of dicumyl peroxide and 2mL of DMSO are sequentially added into a 10mL thick-walled pressure tube, and the mixture is magnetically stirred for reaction for 24 hours under the irradiation of a 24W blue LED, and the reaction progress is monitored by TLC. After the reaction is finished, column chromatography separation is carried out to obtain (petroleum ether (60-90 ℃)/ethyl acetate (15:1)]To give 8- (4' -fluoro) phenyl-3, 4-dicarboxylic acid methyl ester quinoline 3d as a white solid (18 mg) with a yield of 53%.¹H NMR(400MHz,CDCl₃,ppm)δ9.46(s,1H),7.89-7.81(m,2H),7.73(dd, J＝8.4,7.2Hz,1H),7.45(ddd,J＝24.9,17.1,10.1Hz,3H),7.17-7.11(m,1H),4.13(s,3H),4.01 (s,3H).¹³C NMR(100MHz,CDCl₃Ppm) δ 167.49,164.76,163.66, 149.55,147.20,142.64, 140.64(d, J-8.0 Hz),140.10(d, JC-F-2.0 Hz),132.87,129.51(d, JC-F-8.4 Hz),128.10, 126.29(d, JC-F-2.9 Hz),125.99,123.60118.89,117.71 (d, JC-F-22), 114.71(d, JC-F-21), 53.27,52.99. the reaction principle of example 10 is of the formula:

example 11 of implementation: 0.023g (0.1mmol) of N-methyl-4' -methyl-5-chlorobiphenyl-2-amine 1e, 0.028g (0.2mmol) of methyl butynedicarboxylate 2a, 0.054g (0.2mmol) of dicumyl peroxide and 2mL of DMSO are sequentially added into a 10mL thick-wall pressure-resistant tube, and the reaction is magnetically stirred for 24 hours under the irradiation of a 24W blue LED, and the reaction progress is monitored by TLC. After the reaction is finished, column chromatography separation is carried out to obtain (petroleum ether (60-90 ℃)/ethyl acetate (15:1)]To give 8- (4' -methyl) phenyl-5-chloro-3, 4-dicarboxylic acid methyl ester quinoline 3e as a white solid (21 mg) with a yield of 56%.¹H NMR(400MHz,CDCl₃,ppm)δ9.41(s,1H),7.81(d, J＝2.2Hz,1H),7.77(d,J＝2.2Hz,1H),7.53(d,J＝8.0Hz,2H),7.32(d,J＝7.9Hz,2H),7.26(s, 1H),4.13(s,3H),4.00(s,3H),2.44(s,3H).¹³C NMR(100MHz,CDCl₃Ppm) delta 167.09, 164.62, 149.34,146.13,143.28,141.55,138.28,134.36,134.18,133.20,130.43,128.96,124.47,123.65, 119.65,53.39,53.04,21.29 the reaction principle for carrying out example 11 is as follows:

example 12 of implementation: 0.023g (0.1mmol) of N-methyl-1-naphthyl-benzene-2-amine 1f, 0.028g (0.2mmol) of methyl butynedicarboxylate 2a, 0.054g (0.2mmol) of dicumyl peroxide and 2mL of DMSO are sequentially added into a 10mL thick-walled pressure tube, and the reaction is magnetically stirred for 24h under the irradiation of 24W blue LED, and the reaction progress is monitored by TLC. After the reaction is finished, column chromatography separation is carried out to obtain (petroleum ether (60-90 ℃)/ethyl acetate (15:1)]8-naphthyl-3, 4-dicarboxylic acid methyl ester quinoline 3f is obtained in the form of a white solid (18 mg) with a yield of 48%.¹H NMR(400Hz,CDCl₃)(δ,ppm)9.30(s,1H),8.00-7.92(m,3H),7.90(dd,J＝7.0, 1.2Hz,1H),7.78(dd,J＝8.1,7.3Hz,1H),7.65-7.58(m,1H),7.53-7.43(m,2H),7.32-7.22(m, 3H),4.16(s,3H),3.97(s,3H)；¹³C NMR(100MHz,CDCl₃) δ 167.66,164.82,149.59,148.54, 142.56,140.71,136.97,134.14,133.42,132.57,128.42,128.27,128.04,127.80,126.30,125.92, 125.90,125.70,125.24,123.25,118.76,53.30,52.93 the reaction principle for carrying out example 12 is as follows:

example 13: 0.020g (0.1mmol) of N-methyl-4-fluoro-biphenyl-2-amine 1g, 0.028g (0.2mmol) of methyl butynedicarboxylate 2a, 0.054g (0.2mmol) of dicumyl peroxide and 2mL of DMSO are sequentially added into a 10mL thick-walled pressure tube, and the reaction is magnetically stirred for 24 hours under the irradiation of a 24W blue LED, and the reaction progress is monitored by TLC. After the reaction is finished, column chromatography separation is carried out to obtain (petroleum ether (60-90 ℃)/ethyl acetate (15:1)]This gave 3g of 8-phenyl-4-fluoro-3, 4-dicarboxylic acid methyl ester quinoline in the form of a white solid (15 mg, 45%).¹H NMR(500Hz,CDCl₃)(δ,ppm)9.40(s,1H),7.67(d,J＝2.7Hz,1H),7.65 (d,J＝7.1Hz,2H),7.52(t,J＝7.4Hz,2H),7.49-7.42(m,2H),4.12(s,3H),4.01(s,3H)；¹³C NMR(100MHz,CDCl₃)δ167.13,164.72,148.55(d,J C-F＝2.5Hz)，144.88，144.45(d,J C-F＝9.3Hz),141.85(d,JC-F＝6.3Hz),137.49(d,JC-F＝1.9Hz),130.55,128.37,128.20,124.80(d, JC-F ═ 10.8Hz),122.87,122.66,119.77,108.72,108.53,53.30,53.00 the reaction principle for example 13 was carried out as follows:

example 14 was carried out: 0.018g (0.1mmol) of N-methylbiphenyl-2-amine 1a, 0.034g (0.2mmol) of ethyl butynedicarboxylate 2b, 0.054g (0.2mmol) of dicumyl peroxide and 2mL of DMSO are sequentially added into a 10mL thick-wall pressure-resistant tube, and the reaction is magnetically stirred for 24 hours under the irradiation of 24W blue LED, and the reaction progress is monitored by TLC. After the reaction is finished, column chromatography separation is carried out to obtain (petroleum ether (60-90 ℃)/ethyl acetate (15:1)]This gave 8-phenyl-3, 4-dicarboxylic acid ethyl ester quinoline in 3h as a white solid, 15mg, 43% yield.¹H NMR(500Hz,CDCl₃)(δ,ppm)9.48(s,1H),7.87(ddd,J＝6.2,4.1,1.4Hz,2H),7.72 (dd,J＝8.5,7.0Hz,1H),7.65(dt,J＝3.1,1.8Hz,2H),7.54-7.48(m,2H),7.47-7.41(m,1H), 4.62(q,J＝7.2Hz,2H),4.46(q,J＝7.1Hz,2H),1.48(t,J＝7.2Hz,3H),1.43(t,J＝7.1Hz,3H)；¹³C NMR(100MHz,CDCl₃) δ 167.12, 164.36,149.54,147.38,142.56,141.42,138.65,132.70, 130.61,128.05,128.02,127.76,125.38,123.62,118.88,62.45,61.98,14.14,14.11 the reaction principle for carrying out example 14 is as follows:

example 15 of implementation: 0.018g (0.1mmol) of N-methylbiphenyl-2-amine 1a, 0.045g (0.2mmol) of tert-butyl butynedioate 2c, 0.054g (0.2mmol) of dicumyl peroxide and 2mL of DMSO are sequentially added into a 10mL thick-wall pressure-resistant tube, and the reaction is magnetically stirred for 24 hours under the irradiation of a 24W blue LED, and the reaction progress is monitored by TLC. After the reaction is finished, column chromatography separation is carried out to obtain (petroleum ether (60-90 ℃)/ethyl acetate (15:1)]To obtain 8-phenyl-3, 4-dicarboxylic acid tert-butyl ester quinoline 3i as a white solid (13 mg) with a yield of 31%.¹H NMR(500Hz,CDCl₃)(δ,ppm)9.37(s,1H),7.95(d,J＝8.1Hz,1H),7.83(d,J＝ 6.7Hz,1H),7.73-7.67(m,1H),7.64(d,J＝7.3Hz,2H),7.50(t,J＝7.4Hz,2H),7.44(d,J＝7.2 Hz,1H),1.72(s,9H),1.63(s,9H)；¹³C NMR(100MHz,CDCl₃) δ 166.07, 163.39,149.71,147.13, 142.90,141.27,138.93,132.16,130.56,128.00,127.72,127.60,125.23,123.90,120.54,83.90, 82.59,28.14,28.12 the reaction principle for carrying out example 15 is as follows: