A method for preparing a substituted naphthalene derivative

Abstract

The present invention discloses a preparation method of substituted naphthalene derivatives. The method comprises the following steps: in the presence of methyl trifluoromethanesulfonate and potassium bromide, in a solvent, reacting a compound shown by formula II with a compound shown by formula III to obtain a substituted naphthalene derivative shown by formula I. The present invention relates to a preparation method for efficiently preparing substituted naphthalene derivatives by the synergistic catalysis of an organic reagent methyl trifluoromethanesulfonate (MeOTf) and potassium bromide (KBr). The whole process does not involve metals, the substrates are convenient to obtain, the reaction conditions are mild, and the operation is simple.

Description

Technical Field

[0001] The present invention relates to a method for preparing substituted naphthalene derivatives, belonging to the field of organic synthetic chemistry. Background Art

[0002] Naphthalene is one of the important polycyclic aromatic hydrocarbons. It is widely used in the fields of materials and medicine, as a raw material for preparing dyes, resins, solvents, etc., and also as an insect repellent. Its preparation method is mainly obtained from the by-product coal tar of coking. Developing a method for constructing multi-substituted naphthalene derivatives, especially how to efficiently and economically construct a synthetic strategy for substituted naphthalene derivatives, is particularly important. Naphthalene skeleton derivatives have good biological activities. For example, carbaryl is a broad-spectrum carbamate insecticide used to control pests of crops, trees and ornamental plants; naphthalene skeleton derivatives are present in a variety of natural arylnaphthol lactones and have a wide range of biological activities. Among them, the natural bioactive substances (dehydrodendrobine) extracted from Juniperus chinensis and (isodaurinoline) extracted from Cornus officinalis are all derivatives with a naphthalene nucleus as the skeleton. Substituted naphthalene derivatives can be used as a precursor of bioactive drug molecules and have high potential for drug utilization. At present, metal participation is required in the synthesis of its drug molecules. Trace metals remaining in the drug molecules not only have a certain impact on the drug efficacy, but also cause economic losses in their post-treatment process. Therefore, there is an urgent need for a method for efficiently preparing multi-substituted naphthalene derivatives without metal participation throughout the process, with easily available substrates, mild reaction conditions and simple operations. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for preparing substituted naphthalene derivatives. A method for efficiently preparing substituted naphthalene derivatives by the synergistic catalysis of the organic reagent methyl trifluoromethanesulfonate (MeOTf) and potassium bromide (KBr), without an inert gas environment, without metal participation throughout the process, with easily available substrates, mild reaction conditions and simple operations.

[0004] The method for preparing substituted naphthalene derivatives provided by the present invention includes the following steps: in the presence of methyl trifluoromethanesulfonate and potassium bromide, in a solvent, the compound shown in Formula II reacts with the compound shown in Formula III to obtain the substituted naphthalene derivative shown in Formula I.

[0005]

[0006] In the above Formula II and Formula III, R 1 or R 2independently represent at least one of the following monosubstituted or polysubstituted groups: hydrogen, halogen, straight-chain or branched C1-C6 alkyl (specifically straight-chain or branched C1-C3 alkyl, more specifically methyl or isopropyl), C1-C5 alkoxy (specifically methoxy), halogen-substituted C1-C3 alkyl (specifically trifluoromethyl), and aryl fused to the existing benzene ring; R 1 and R 2 are at any possible position in the benzene ring; the aryl fused to the existing benzene ring is specifically phenyl;

[0007] The compounds represented by Formula II and Formula III can be the same compound;

[0008] R 1 and R 2 in Formula I are respectively the same as R 1 and R 2 in Formula II and Formula III;

[0009] In the present invention, the structural formula of the compound represented by the polysubstituted naphthalene derivative of Formula I is specifically as shown in Formulae 1-14 below:

[0010] In the above preparation method, the molar ratio of methyl trifluoromethanesulfonate (MeOTf), potassium bromide (KBr), and the compounds represented by Formula II and Formula III can be 0.03-0.05:0.10-0.15:1.0:1.0, specifically 0.05:0.1:1.0:1.0.

[0011] In the present invention, the addition order of the raw materials is to first add potassium bromide (KBr), then add the compound represented by II and the compound represented by Formula III into the reaction vessel, add a solvent and mix well, and finally add methyl trifluoromethanesulfonate (MeOTf).

[0012] In the above preparation method, the temperature of the reaction can be 120-130 °C, and the time can be 10-30 minutes, specifically 10 minutes or 30 minutes.

[0013] In the above preparation method, the solvent is an alcohol, specifically ethanol; the solvent is a solvent treated with activated molecular sieve, and the molecular sieve used is a commercial reagent, which is heated in a muffle furnace at 350-400 °C for 5-6 hours before use.

[0014] In the above preparation method, the post-treatment of the reaction is as follows: without quenching or extraction, after the reaction is completed, the organic phase is directly transferred to a rotary evaporation flask and the organic solvent is removed by reduced pressure distillation to obtain a crude product; the crude product is subjected to column chromatography separation using petroleum ether as an eluent and the adsorption phase of a silica gel column (diameter 30 mm, filled with silica gel 50 mm high) to obtain a pure target product.

[0015] The present invention has the following advantages:

[0016] 1. The preparation method of the substituted naphthalene ring derivative containing a naphthalene ring structural unit provided by the present invention is scientific and reasonable, and the target product with a high yield is obtained by a one-pot method;

[0017] 2. The operation of the present invention is simple. After the reaction is completed, there is no need to quench, and the post-treatment separation and purification can be directly carried out;

[0018] 3. The present invention uses the organic reagents methyl trifluoromethanesulfonate (MeOTf) and potassium bromide (KBr) as catalysts to efficiently catalyze the preparation of substituted naphthalene derivatives. The whole reaction process does not involve metals, avoiding the treatment process of trace residual metal compounds;

[0019] 4. The reaction conditions are mild, the operation is simple, the substrates are easily available, and the separation yield is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 1H NMR spectrum of the compound prepared in Example 1 1 1H NMR spectrum.

[0021] Figure 2 1H NMR spectrum of the compound prepared in Example 2 1 1H NMR spectrum.

[0022] Figure 3 1H NMR spectrum of the compound prepared in Example 3 1 1H NMR spectrum.

[0023] Figure 4 1H NMR spectrum of the compound prepared in Example 4 1 1H NMR spectrum. DETAILED DESCRIPTION OF THE INVENTION

[0024] The experimental methods used in the following examples are all conventional methods unless otherwise specified.

[0025] The materials, reagents, etc. used in the following examples can be obtained from commercial channels unless otherwise specified.

[0026] The preparation method of the substituted naphthalene derivative provided by the present invention includes the following steps: in the presence of methyl trifluoromethanesulfonate and potassium bromide, in a solvent, the compound shown in Formula II reacts with the compound shown in Formula III to obtain the substituted naphthalene derivative shown in Formula I,

[0027]

[0028] In the above Formula II and Formula III, R 1 or R 2independently represent a monosubstituted or polysubstituted group selected from the group consisting of hydrogen, halogen, a straight-chain or branched C1-C6 alkyl group (specifically a straight-chain or branched C1-C3 alkyl group, more specifically methyl or isopropyl), a C1-C5 alkoxy group, a halogen-substituted C1-C3 alkyl group (specifically trifluoromethyl), and an aryl group fused to the existing benzene ring; R 1 and R 2 are at any possible position in the benzene ring; the aryl group fused to the existing benzene ring is specifically a phenyl group;

[0029] R in formula I 1 and R 2 are respectively the same as R 1 and R 2 in formula II and formula III respectively.

[0030] In the above preparation method, the molar ratio of methyl trifluoromethanesulfonate (MeOTf), potassium bromide (KBr), and the compounds represented by formula II and formula III can be 0.03 - 0.05:0.10 - 0.15:1.0:1.0 in sequence, specifically 0.05:0.1:1.0:1.0. In the present invention, the raw materials are added in the following order: first add potassium bromide (KBr), then add the compound represented by II and the compound represented by formula III into the reaction vessel, add a solvent and mix well, and finally add methyl trifluoromethanesulfonate (MeOTf).

[0031] In the above preparation method, the reaction temperature can be 120 - 130 °C, and the reaction time can be 10 - 30 minutes, specifically 10 minutes or 30 minutes.

[0032] In the above preparation method, the solvent is an alcohol, specifically ethanol; the solvent is a solvent treated with activated molecular sieve, and the molecular sieve used is a commercial reagent, which is heated in a muffle furnace at 350 - 400 °C for 5 - 6 hours before use.

[0033] In the above preparation method, the post-treatment of the reaction is as follows: no quenching or extraction is required. After the reaction is completed, the organic phase is directly transferred to a rotary evaporation flask and the organic solvent is removed by vacuum distillation to obtain a crude product; the crude product is subjected to column chromatography separation using petroleum ether as an eluent and the adsorption phase of a silica gel column (with a diameter of 30 mm and a height of 50 mm filled with silica gel) to obtain a pure target product.

[0034] The present invention provides a method for efficiently preparing substituted naphthalene derivatives by the synergistic catalysis of methyl trifluoromethanesulfonate (MeOTf) and potassium bromide (KBr), without the need for an inert gas environment, no metal is involved in the whole process, the substrates are easily available, the reaction conditions are mild, and the operation is simple.

[0035] The ethylene oxide derivatives used in the following examples were prepared from trimethylsulfonium iodide and aryl aldehydes or ketones according to the method in the literature (E.J.Corey, Michael Chaykovsky, J.Am.Chem.Soc., 1965, 87, 1353); both trimethylsulfonium iodide and aryl aldehydes or ketones are commercially available.

[0036] The solvent ethanol used in the following examples was treated with activated molecular sieves before use.

[0037] Example 1, 2-Phenylnaphthalene

[0038] Under air conditions, potassium bromide (1.19 mg, 0.01 mmol) and epibromohydrin (24.0 mg, 0.2 mmol) were successively added to a 25 mL reactor, and then ethanol (abbreviated as EtOH, 0.5 mL) was added. After waiting for the substrate to completely dissolve, methyl trifluoromethanesulfonate (0.84 mg, 5 mol%) was added successively. The reactor was sealed and slowly heated to 130 °C and reacted at 130 °C for 10 minutes. After the reaction system cooled down, the organic phase was directly transferred to a rotary evaporation flask and the organic solvent was removed by distillation under reduced pressure to obtain a crude product. The crude product was separated by column chromatography using petroleum ether as the eluent and silica powder as the adsorbent phase to obtain 18.6 mg of pure white solid product 2-phenylnaphthalene, with a separation yield of 91%.

[0039] Structure identification of 1,2-diphenylnaphthalene: Nuclear magnetic resonance data: 1 H NMR (400 MHz, CHLOROFORM-D) δ8.04 (s, 1H), 7.93 - 7.86 (m, 3H), 7.76 - 7.72 (m, 3H), 7.51 - 7.47 (m, 4H), 7.40 - 7.36 (m, 1H). 13 C NMR (101 MHz, CHLOROFORM-D) δ141.29, 138.72, 132.83, 132.77, 129.00, 128.56, 128.34, 127.79, 127.58, 127.50, 126.43, 126.07, 125.95, 125.74.

[0040] GC-MS data: m / z: 204

[0041] The analysis results show that the obtained target product is correct.

[0042] Example 2, 2-Methyl-7-(p-tolyl)naphthalene

[0043] Under air conditions, potassium bromide (1.19 mg, 0.01 mmol) and 2-(p-tolyl)oxirane (26.8 mg, 0.2 mmol) were successively added to a 25 mL reactor, and then ethanol (abbreviated as EtOH, 0.5 mL) was added. After waiting for the substrates to completely dissolve, methyl trifluoromethanesulfonate (0.84 mg, 5 mol%) was added successively. The reactor was sealed and slowly heated to 130 °C and reacted at 130 °C for 10 minutes. After the reaction system cooled down, the organic phase was directly transferred to a rotary evaporation flask and the organic solvent was removed by distillation under reduced pressure to obtain the crude product. The crude product was separated by column chromatography using petroleum ether as the eluent and silica gel powder as the adsorption phase to obtain 21.4 mg of pure white solid product 2-methyl-7-(p-tolyl)naphthalene, with a separation yield of 92%.

[0044] Structure identification of 2-methyl-7-(p-tolyl)naphthalene: Nuclear magnetic resonance data: 1 H NMR(400MHz, CHLOROFORM-D)δ8.00(s, 1H), 7.84 - 7.80(m, 2H), 7.73 - 7.71(m, 1H), 7.64(s, 1H), 7.55 - 7.52(m, 2H), 7.40 - 7.3(m, 2H), 7.21 - 7.19(m, 1H), 2.54(s, 1H), 2.47(s, 1H). 13 C NMR(101MHz, CHLOROFORM-D)δ143.20, 140.21, 139.54, 138.82, 132.98, 132.86, 132.64, 131.32, 130.07, 129.43, 129.07, 129.00, 128.78, 128.02, 127.91, 127.41, 127.38, 126.88, 22.25.

[0045] GC-MS data: m / z: 232

[0046] The analysis results indicate that the obtained target product is correct.

[0047] Example 3, 2-isopropyl-7-(4-isopropylphenyl)naphthalene

[0048] Under air conditions, potassium bromide (1.19 mg, 0.01 mmol) and 2-(4-isopropylphenyl)oxirane (32.4 mg, 0.2 mmol) were successively added to a 25 mL reactor, and then ethanol (abbreviated as EtOH, 0.5 mL) was added. After waiting for the substrates to completely dissolve, methyl trifluoromethanesulfonate (0.84 mg, 5 mol%) was added successively. The reactor was sealed and slowly heated to 128 °C and reacted at 128 °C for 10 minutes. After the reaction system was cooled, the organic phase was directly transferred to a rotary evaporation flask and the organic solvent was removed by distillation under reduced pressure to obtain the crude product. The crude product was separated by column chromatography using petroleum ether as the eluent and silica gel powder as the adsorption phase to obtain 25.4 mg of pure white solid product 2-isopropyl-7-(4-isopropylphenyl)naphthalene, with a separation yield of 88%.

[0049] Structure identification of 2-isopropyl-7-(4-isopropylphenyl)naphthalene: Nuclear magnetic resonance data: 1 H NMR (400 MHz, CHLOROFORM-D) δ 7.97 (s, 1H), 7.84 (d, J = 3.5 Hz, 1H), 7.78 (d, J = 3.5 Hz, 1H), 7.68 - 7.64 (m, 4H), 7.39 - 7.33 (m, 3H), 3.09 - 3.06 (m, 1H), 2.99 - 2.96 (m, 1H), 1.36 (s, 3H), 1.34 (s, 3H), 1.32 (s, 3H), 1.30 (s, 3H). 13 C NMR (101 MHz, CHLOROFORM-D) δ 148.16, 146.89, 138.96, 138.62, 134.08, 131.31, 128.12, 127.71, 127.44, 127.06, 125.86, 125.38, 124.98, 124.50, 34.42, 33.99, 22.81.

[0050] GC-MS data: m / z: 288

[0051] The analysis results indicate that the obtained target product is correct.

[0052] Example 4, 2-(naphthalen-2-yl)anthracene

[0053] Under air conditions, potassium bromide (1.19 mg, 0.01 mmol) and 2-(naphthalen-2-yl)oxirane (34.0 mg, 0.2 mmol) were successively added to a 25 mL reactor, and then ethanol (abbreviated as EtOH, 0.5 mL) was added. After waiting for the substrates to completely dissolve, methyl trifluoromethanesulfonate (0.84 mg, 5 mol%) was added successively. The reactor was sealed and slowly heated to 125 °C, and the reaction was carried out at 125 °C for 10 minutes. After the reaction system was cooled, the organic phase was directly transferred to a rotary evaporation flask and the organic solvent was removed by distillation under reduced pressure to obtain the crude product. The crude product was separated by column chromatography using petroleum ether as the eluent and silica powder as the adsorbent phase to obtain 28.9 mg of pure colorless liquid product 2-(naphthalen-2-yl)anthracene, with a separation yield of 95%.

[0054] Structure identification of 2-(naphthalen-2-yl)anthracene: Nuclear magnetic resonance data: 1 H NMR(400MHz,CHLOROFORM-D)δ9.04(s,1H),8.85(d,J=3.5Hz,1H),8.26(d,J=1.0Hz,1H),8.01-7.94(m,7H),7.83-7.78(m,2H),7.74-7.70(m,1H),7.71-7.66(m,1H),7.61-7.54(m,2H). 13 C NMR(101MHz,CHLOROFORM-D)δ139.36,138.95,133.91,132.82,132.47,131.37,130.74,130.54,129.23,128.82,128.71,128.39,127.83,127.21,126.85,126.76,126.70,126.52,126.39,126.31,126.16,126.02,122.85,121.50.

[0055] GC-MS data: m / z: 304

[0056] The analysis results showed that the obtained target product was correct.

[0057] Example 5, 2-Bromo-7-(4-bromophenyl)naphthalene

[0058] Under air conditions, potassium bromide (1.19 mg, 0.01 mmol) and 2-(4-bromophenyl)oxirane (39.8 mg, 0.2 mmol) were successively added to a 25 mL reactor, and then ethanol (abbreviated as EtOH, 0.5 mL) was added. After waiting for the substrates to completely dissolve, methyl trifluoromethanesulfonate (0.84 mg, 5 mol%) was added successively. The reactor was sealed and slowly heated to 130 °C and reacted at 130 °C for 30 minutes. After the reaction system cooled down, the organic phase was directly transferred to a rotary evaporation flask and the organic solvent was removed by distillation under reduced pressure to obtain the crude product. The crude product was separated by column chromatography using petroleum ether as the eluent and silica gel powder as the adsorption phase to obtain 23.2 mg of pure yellow solid product 2-bromo-7-(4-bromophenyl)naphthalene, with a separation yield of 64%.

[0059] Structure identification of 2-bromo-7-(4-bromophenyl)naphthalene: Nuclear magnetic resonance data: 1 H NMR(400MHz,CHLOROFORM-D)δ8.25(d,J=12.5Hz,1H),7.89(d,J=8.0Hz,1H),7.81(s,2H),7.58(d,J=2.0Hz,1H),7.33-7.29(m,2H),7.17-7.13(m,2H),7.15-7.06(m,2H). 13 C NMR(101MHz,CHLOROFORM-D)δ137.64,135.96,135.62,133.02,131.38,129.41,128.35,127.92,127.62,126.95,126.68,123.75,122.04,119.92,116.82.

[0060] GC-MS data: m / z: 362

[0061] The analysis results showed that the obtained target product was correct.

[0062] Example 6, 2-(trifluoromethyl)-7-(4-(trifluoromethyl)phenyl)naphthalene

[0063] Under air conditions, potassium bromide (1.19 mg, 0.01 mmol) and 2-(4-bromophenyl)oxirane (37.6 mg, 0.2 mmol) were successively added to a 25 mL reactor, and then ethanol (abbreviated as EtOH, 0.5 mL) was added. After waiting for the substrates to completely dissolve, methyl trifluoromethanesulfonate (0.84 mg, 5 mol%) was added successively. The reactor was sealed and slowly heated to 130 °C, and the reaction was carried out at 130 °C for 30 minutes. After the reaction system was cooled, the organic phase was directly transferred to a rotary evaporation flask and the organic solvent was removed by distillation under reduced pressure to obtain the crude product. The crude product was separated by column chromatography using petroleum ether as the eluent and silica gel powder as the adsorbent phase to obtain 19.7 mg of the pure yellow solid product 2-(trifluoromethyl)-7-(4-(trifluoromethyl)phenyl)naphthalene, with a separation yield of 58%.

[0064] Structure identification of 2-(trifluoromethyl)-7-(4-(trifluoromethyl)phenyl)naphthalene: Nuclear magnetic resonance data: 1 H NMR(600MHz,CHLOROFORM-D)δ7.93-7.85(m,3H),7.76-7.74(m,2H),7.53-7.49(m,4H),7.47-7.36(m,1H). 13 C NMR(151MHz,CHLOROFORM-D)δ141.29,138.72,133.83,132.77,129.00(d,J=8.5Hz),128.55,128.34(d,J=4.2Hz),127.79,127.58,127.50,126.43,126.07,125.95(d,J=24.3Hz),125.74. 19 F NMR(565MHz,CHLOROFORM-D)δ-63.59.

[0065] GC-MS data: m / z: 340

[0066] The analysis results show that the obtained target product is correct.

[0067] Example 7, 2-Fluoro-7-(4-fluorophenyl)naphthalene

[0068] Under air conditions, potassium bromide (1.19 mg, 0.01 mmol) and 2-(4-fluorophenyl)oxirane (27.6 mg, 0.2 mmol) were successively added to a 25 mL reactor, and then ethanol (abbreviated as EtOH, 0.5 mL) was added. After waiting for the substrates to completely dissolve, methyl trifluoromethanesulfonate (0.84 mg, 5 mmol%) was added successively. The reactor was sealed and slowly heated to 130 °C and reacted at 130 °C for 10 minutes. After the reaction system cooled down, the organic phase was directly transferred to a rotary evaporation flask and the organic solvent was removed by distillation under reduced pressure to obtain the crude product. The crude product was separated by column chromatography using petroleum ether as the eluent and silica powder as the adsorbent phase to obtain 14.4 mg of pure white solid product 2-fluoro-7-(4-fluorophenyl)naphthalene, with a separation yield of 60%.

[0069] Structure identification of 2-fluoro-7-(4-fluorophenyl)naphthalene: Nuclear magnetic resonance data: 1 H NMR(600MHz,CHLOROFORM-D)δ7.98-7.92(m,2H),7.82-7.76(m,1H),7.67(s,3H),7.48-7.44(m,2H),7.40-7.36(m,2H). 13 C NMR(151MHz,CHLOROFORM-D)δ161.60,160.68,129.00,128.55,128.34,127.79,127.58,127.50,126.43(d,J=4.3Hz),126.07,125.95,125.74(d,J=7.2Hz),116.63,111.01(d,J=22.3Hz). 19 F NMR(565MHz,CHLOROFORM-D)δ-113.98,-114.98.

[0070] GC-MS data: m / z: 240

[0071] The analysis results showed that the obtained target product was correct.

[0072] Example 8, 1-bromo-6-(2-bromophenyl)naphthalene

[0073] Under air conditions, potassium bromide (1.19 mg, 0.01 mmol) and 2-(2-bromophenyl)oxirane (39.8 mg, 0.2 mmol) were successively added to a 25 mL reactor, and then ethanol (abbreviated as EtOH, 0.5 mL) was added. After waiting for the substrates to completely dissolve, methyl trifluoromethanesulfonate (0.84 mg, 5 mol%) was added successively. The reactor was sealed and slowly heated to 130 °C, and the reaction was carried out at 130 °C for 10 minutes. After the reaction system was cooled, the organic phase was directly transferred to a rotary evaporation flask and the organic solvent was removed by distillation under reduced pressure to obtain the crude product. The crude product was separated by column chromatography using petroleum ether as the eluent and silica gel powder as the adsorbent phase to obtain 15.9 mg of the pure yellow solid product 1-bromo-6-(2-bromophenyl)naphthalene, with a separation yield of 44%.

[0074] Structure identification of 1-bromo-6-(2-bromophenyl)naphthalene: Nuclear magnetic resonance data: 1 H NMR (400 MHz, CHLOROFORM-D) δ 8.04 (d, J = 1.0 Hz, 1H), 7.92 - 7.85 (m, 3H), 7.76 - 7.71 (m, 2H), 7.50 - 7.45 (m, 3H), 7.39 - 7.35 (m, 1H). 13 C NMR (101 MHz, CHLOROFORM-D) δ 129.00, 128.80, 128.64, 128.55, 128.34, 127.90, 127.79, 127.58, 127.49, 126.42, 126.24, 126.01, 125.95, 125.75.

[0075] GC-MS data: m / z: 362

[0076] The analysis results show that the obtained target product is correct.

[0077] Example 9, 1-methyl-6-(o-tolyl)naphthalene

[0078] Under air conditions, potassium bromide (1.19 mg, 0.01 mmol) and 2-(2-methylphenyl)oxirane (26.8 mg, 0.2 mmol) were successively added to a 25 mL reactor, and then ethanol (abbreviated as EtOH, 0.5 mL) was added. After waiting for the substrates to completely dissolve, methyl trifluoromethanesulfonate (0.84 mg, 5 mol%) was added successively. The reactor was sealed and slowly heated to 130 °C, and the reaction was carried out at 130 °C for 10 minutes. After the reaction system was cooled, the organic phase was directly transferred to a rotary evaporation flask and the organic solvent was removed by distillation under reduced pressure to obtain the crude product. The crude product was separated by column chromatography using petroleum ether as the eluent and silica gel powder as the adsorbent phase to obtain 18.1 mg of the pure white solid product 1-methyl-6-(o-tolyl)naphthalene, with a separation yield of 78%.

[0079] Structural identification of 1-methyl-6-(o-tolyl)naphthalene: NMR data: 1 H NMR(400MHz,CHLOROFORM-D)δ8.19(d,J=4.0Hz,1H),7.92-7.85(m,1H),7.76-7.71(m,2H),7.57-7.46(m,5H),7.29-7.26(m,1H),2.57(s,3H),2.23(s,3H). 13 C NMR(101MHz,CHLOROFORM-D)δ137.85,135.00,134.41,132.35,129.44,128.54,125.34,125.14,124.74,124.60,124.55,124.27,123.21,122.28,122.11,121.06,18.36,18.20.

[0080] GC-MS data: m / z: 232

[0081] The analysis results indicate that the obtained target product is correct.

[0082] Example 10, 6-(2,5-dimethoxyphenyl)-1,4-dimethoxynaphthalene

[0083] Under air conditions, potassium bromide (1.19 mg, 0.01 mmol) and 2-(2,5-dimethoxyphenyl)oxirane (36.0 mg, 0.2 mmol) were successively added to a 25 mL reactor, and then ethanol (abbreviated as EtOH, 0.5 mL) was added. After the substrate was completely dissolved, methyl trifluoromethanesulfonate (0.84 mg, 5 mol%) was successively added. The reactor was sealed and slowly heated to 130 °C and reacted at 130 °C for 10 minutes. After the reaction system was cooled, the organic phase was directly transferred to a rotary evaporation flask and the organic solvent was removed by distillation under reduced pressure to obtain a crude product. The crude product was separated by column chromatography using petroleum ether as the eluent and silica gel powder as the adsorption phase to obtain 10.4 mg of pure white solid product 6-(2,5-dimethoxyphenyl)-1,4-dimethoxynaphthalene, and the separation yield was 32%.

[0084] Structural identification of 6-(2,5-dimethoxyphenyl)-1,4-dimethoxynaphthalene: NMR data: 11H NMR (400 MHz, CHLOROFORM-D) δ 8.30 - 8.23 (m, 2H), 7.25 - 7.21 (m, 1H), 7.14 - 7.07 (m, 2H), 6.06 (d, J = 1.0 Hz, 1H), 5.95 (d, J = 2.0 Hz, 2H), 3.81 (s, 3H), 3.79 (s, 9H). 13 13C NMR (101 MHz, CHLOROFORM-D) δ 153.71, 150.52, 149.45, 139.57, 132.47, 131.34, 129.17, 129.07, 128.82, 127.76, 127.56, 126.76, 126.72, 126.17, 112.42, 104.05, 56.93, 56.24, 56.03, 55.37.

[0085] GC-MS data: m / z: 324

[0086] The analysis results indicate that the obtained target product is correct.

[0087] Example 11, 2-Methyl-7-phenylnaphthalene

[0088] Under air conditions, potassium bromide (1.19 mg, 0.01 mmol), 2-phenyloxirane (12.0 mg, 0.1 mmol), and 2-(p-tolyl)oxirane (13.4 mg, 0.1 mmol) were successively added to a 25 mL reactor, and then ethanol (abbreviated as EtOH, 0.5 mL) was added. After the substrates were completely dissolved, methyl trifluoromethanesulfonate (0.84 mg, 5 mol%) was added successively. The reactor was sealed and slowly heated to 130 °C and reacted at 130 °C for 10 minutes. After the reaction system was cooled, the organic phase was directly transferred to a rotary evaporation flask and the organic solvent was removed by distillation under reduced pressure to obtain a crude product. The crude product was separated by column chromatography using petroleum ether as the eluent and silica gel powder as the adsorbent phase to obtain 18.8 mg of pure white solid product 2-methyl-7-phenylnaphthalene with a separation yield of 86%.

[0089] Structure identification of 2-methyl-7-phenylnaphthalene: Nuclear magnetic resonance data: 1 1H NMR (400 MHz, CHLOROFORM-D) δ 8.03 - 7.99 (m, 1H), 7.91 - 7.82 (m, 1H), 7.79 - 7.71 (m, 1H), 7.70–7.68 (m, 2H), 7.61 (s, 1H), 7.52 - 7.44 (m, 3H), 7.38 - 7.33 (m, 2H), 2.51 (s, 3H). 1313C NMR (101 MHz, CHLOROFORM-D) δ 141.39, 138.70, 137.80, 135.75, 133.82, 132.98, 132.76, 132.06, 128.95, 128.55, 127.48, 127.32, 126.74, 126.06, 125.72, 21.89.

[0090] GC-MS data: m / z: 218

[0091] The analysis results indicate that the obtained target product is correct.

[0092] Example 12, 2-Isopropyl-7-phenylnaphthalene

[0093] Under air conditions, potassium bromide (1.19 mg, 0.01 mmol), 2-phenyloxirane (12.0 mg, 0.1 mmol), and 2-(4-isopropylphenyl)oxirane (16.2 mg, 0.1 mmol) were successively added to a 25 mL reactor. Then ethanol (abbreviated as EtOH, 0.5 mL) was added. After waiting for the substrates to completely dissolve, methyl trifluoromethanesulfonate (0.84 mg, 5 mol%) was added successively. The reactor was sealed and slowly heated to 130 °C and reacted at 130 °C for 10 minutes. After the reaction system cooled down, the organic phase was directly transferred to a rotary evaporation flask and the organic solvent was removed by distillation under reduced pressure to obtain a crude product. The crude product was separated by column chromatography using petroleum ether as the eluent and silica gel powder as the adsorbent phase to obtain 20.7 mg of pure white solid product 2-isopropyl-7-phenylnaphthalene, with a separation yield of 84%.

[0094] Structure identification of 2-isopropyl-7-phenylnaphthalene: Nuclear magnetic resonance data: 1 1H NMR (400 MHz, CHLOROFORM-D) δ 8.05 (s, 1H), 7.94 - 7.87 (m, 2H), 7.77 - 7.72 (m, 3H), 7.51 - 7.48 (m, 4H), 7.41 - 7.37 (m, 1H), 2.91 - 2.85 (m, 1H), 1.54 (s, 6H). 13 13C NMR (101 MHz, CHLOROFORM-D) δ 141.29, 138.72, 133.83, 132.72, 129.00, 128.55, 128.34, 127.79, 127.58, 127.50, 126.42, 126.07, 125.95, 125.74, 38.71, 24.08.

[0095] GC-MS data: m / z: 246

[0096] The analysis results indicate that the obtained target product is correct.

[0097] Example 13, 2-Phenylanthracene

[0098] Under air conditions, potassium bromide (1.19 mg, 0.01 mmol), 2-phenyloxirane (12.0 mg, 0.1 mmol), and 2-(naphthalen-2-yl)oxirane (17.0 mg, 0.1 mmol) were successively added to a 25 mL reactor. Then ethanol (abbreviated as EtOH, 0.5 mL) was added. After waiting for the substrates to completely dissolve, methyl trifluoromethanesulfonate (0.84 mg, 5 mol%) was added successively. The reactor was sealed and slowly heated to 130 °C and reacted at 130 °C for 10 minutes. After the reaction system cooled down, the organic phase was directly transferred to a rotary evaporation flask and the organic solvent was removed by distillation under reduced pressure to obtain the crude product. The crude product was separated by column chromatography using petroleum ether as the eluent and silica gel powder as the adsorbent phase to obtain 23.0 mg of pure colorless liquid product 2-phenylanthracene, with a separation yield of 90%.

[0099] Structure identification of 2-phenylanthracene: Nuclear magnetic resonance data: 1 H NMR (400 MHz, CHLOROFORM-D) δ 8.88 (d, J = 1.0 Hz, 1H), 8.77 (d, J = 4.0 Hz, 1H), 7.97 - 7.95 (m, 1H), 7.92 - 7.90 (m, 1H), 7.86 - 7.83 (m, 1H), 7.80 - 7.76 (m, 4H), 7.69 - 7.65 (m, 2H), 7.63 - 7.61 (m, 2H), 7.54 - 7.41 (m, 1H). 13 C NMR (101 MHz, CHLOROFORM-D) δ 141.71, 139.57, 129.17, 129.07, 128.83, 127.76, 127.17, 126.85, 126.76, 126.72, 126.17, 122.82, 121.29.

[0100] GC-MS data: m / z: 254

[0101] The analysis results indicate that the obtained target product is correct.

[0102] Example 14, 2-(4-Bromophenyl)naphthalene

[0103] Under air conditions, potassium bromide (1.19 mg, 0.01 mmol), 2-phenyloxirane (12.0 mg, 0.1 mmol), and 2-(4-bromophenyl)oxirane (20.0 mg, 0.1 mmol) were successively added to a 25 mL reactor. Then, ethanol (abbreviated as EtOH, 0.5 mL) was added. After waiting for the substrates to completely dissolve, methyl trifluoromethanesulfonate (0.84 mg, 5 mol%) was added successively. The reactor was sealed and slowly heated to 130 °C and reacted at 130 °C for 10 minutes. After the reaction system cooled down, the organic phase was directly transferred to a rotary evaporation flask and the organic solvent was removed by distillation under reduced pressure to obtain the crude product. The crude product was separated by column chromatography using petroleum ether as the eluent and silica gel powder as the adsorption phase to obtain 20.4 mg of pure white solid product 2-(4-bromophenyl)naphthalene, with a separation yield of 72%.

[0104] Structure identification of 2-(4-bromophenyl)naphthalene: Nuclear magnetic resonance data: 1 H NMR (400 MHz, CHLOROFORM-D) δ8.04 (s, 1H), 7.93 - 7.89 (m, 4H), 7.76 - 7.72 (m, 2H), 7.52 - 7.46 (m, 3H), 7.42 - 7.38 (m, 1H). 13 C NMR (101 MHz, CHLOROFORM-D) δ141.29, 138.72, 133.83, 132.77, 131.68, 129.00, 128.56, 128.34, 127.79, 127.58, 126.43, 126.07, 125.95, 125.75.

[0105] GC-MS data: m / z: 283

[0106] The analysis results show that the obtained target product is correct.

Claims

1. A method for preparing a substituted naphthalene derivative, comprising the following steps: in the presence of methyl trifluoromethanesulfonate and potassium bromide, in a solvent, reacting a compound represented by Formula II with a compound represented by Formula III to obtain a substituted naphthalene derivative represented by Formula I, In Formula II and Formula III, R 1 or R 2 independently represents at least one of the following groups which are mono-substituted or multi-substituted: hydrogen, halogen, straight-chain or branched-chain alkyl having 1 to 6 carbon atoms, alkoxy having 1 to 5 carbon atoms, halogen-substituted alkyl having 1 to 3 carbon atoms, and phenyl fused to the existing benzene ring; R 1 and R 2 are at any possible positions in the benzene ring; R in Formula I 1 , R 2 are respectively the same as R 1 and R 2 .

2. The method according to claim 1, wherein: In the method, the molar ratio of methyl trifluoromethanesulfonate, potassium bromide, the compound represented by Formula II, and the compound represented by Formula III is 0.03~0.05 : 0.10~0.15 : 1.0 : 1.0 in sequence.

3. The method according to claim 1 or 2, characterized in that: In the method, the addition order of raw materials is that first potassium bromide is added, then the compound represented by Formula II and the compound represented by Formula III are put into a reaction vessel, a solvent is added and mixed evenly, and finally methyl trifluoromethanesulfonate is added.

4. The method according to claim 1, characterized in that: The temperature of the reaction is 120~130 °C, and the time is 10 - 30 minutes.

5. The method according to claim 1, wherein: The solvent is an alcohol, and the solvent is treated with activated molecular sieve before use.

6. The method according to claim 5, wherein: The solvent is ethanol.

7. The method according to claim 1, characterized in that: The post-treatment of the reaction is as follows: after the reaction is completed, the organic phase is directly transferred into a rotary evaporation flask, and the organic solvent is removed by reduced pressure distillation to obtain a crude product; the crude product is separated by silica gel column chromatography using petroleum ether as an eluent to obtain a pure target product.

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