CN107652280A - One kind has 1,8 naphthalimide compounds and its synthetic method of red fluorescence - Google Patents

Abstract

The invention discloses a class of red light-emitting naphthalimide derivatives and a synthesis method thereof. The structural formula involved in the present invention is shown in formula I. In the formula, R ₁ , R ₂ and R ₃ are alkyl and aryl. The compound involved in the present invention is obtained by direct coupling of 4-bromo-1,8-naphthoimide and a thienyl-containing pyrazoline compound, all of which have very bright red fluorescence.

Description

A class of 1,8-naphthoimide compounds with red fluorescence and its synthesis method

technical field

The invention relates to a class of 1,8-naphthoimide derivatives and a synthesis method thereof, in particular to a class of 1,8-naphthoimide compounds with red fluorescence and a synthesis method thereof.

Background technique

Organic electroluminescent technology (OLED) is a new generation of display technology after picture tube technology, plasma display and liquid crystal panel. One of the cutting-edge topics to come. In OLED, the most critical is the design and preparation of luminescent materials. Among the luminescent materials of red, green and blue colors, green and blue materials not only have many types, but also have excellent luminous performance, and have achieved good results in practical applications, while red materials have been relatively scarce for a long time, and their Luminous brightness and luminous efficiency are relatively low. Therefore, searching for red light materials with excellent performance is one of the focuses of technical personnel in the field of OLED research.

1,8-Naphthimide derivatives have attracted widespread attention because of their unique luminescent properties, and they have good application prospects in high-tech fields such as dyes, ion probes, electroluminescence, lasers, and photovoltaic cells. . The structure of 1,8-naphthalimide has the following characteristics: (1) Coplanarity; (2) Large π-conjugated system. When an electron-donating group is introduced at the 4-position of the naphthalene ring, since the electron-donating group, the naphthalene ring and the imine form a strong "push-pull conjugated electron system", this will make the compound have better luminescence performance. Through the design and synthesis of electron-donating groups, 1,8-naphthoimide materials from blue to red light can be obtained. But so far, most 1,8-naphthoimide compounds have blue or green light, while there are very few 1,8-naphthoimide compounds that emit red light.

Contents of the invention

One of the objectives of the present invention is to disclose a new class of naphthalimide compounds with red fluorescence.

The second object of the present invention is to provide a method for synthesizing the above compound.

The red light-emitting naphthalimide compound of the present invention has a general structural formula as follows:

In the formula, R ₁ represents alkyl, phenyl or substituted phenyl, preferably n-butyl, n-hexyl, isooctyl; R ₂ and R ₃ are alkyl, phenyl, substituted phenyl, aromatic fused ring or substituted Aromatic fused ring, preferably R2 is phenyl and benzothienyl, preferably _R3 is phenyl, _p -methylphenyl, p-methoxyphenyl, p-chlorophenyl, N,N-dimethylphenyl , naphthyl or anthracenyl.

The synthetic method of compound described in the present invention is as follows:

Mix compound II and compound III at a molar ratio of 10:1 to 1:10, add solvent and stir to dissolve, add metal catalyst, base and ligand after deoxygenation and inert gas, and react at 0-150°C for 1 to 72 hours, The solvent was distilled off, and the residue was purified by recrystallization or column chromatography.

The R ₁ , R ₂ and R ₃ involved in the reaction are the same as those mentioned above.

The metal catalyst used in the reaction is palladium powder, palladium carbon, palladium chloride, palladium acetate, tetrakis triphenylphosphine palladium salt, three (dibenzylidene acetone) dipalladium, bis (triphenylphosphine) palladium chloride , benzylbis(triphenylphosphine)palladium chloride, [1,1'-bis(diphenylphosphino)ferrocene]palladium dichloride, triphenylphosphinepalladium acetate, 1,4-bis( Diphenylphosphinobutane) palladium dichloride, cuprous chloride, cuprous bromide, cuprous iodide, cuprous oxide, preferably palladium acetate, tetrakistriphenylphosphine palladium salt, [1,1'- Bis(diphenylphosphino)ferrocene]palladium dichloride or cuprous bromide; said base is cesium carbonate, sodium carbonate, potassium carbonate, cesium acetate, sodium acetate, potassium acetate; said ligand Triphenylphosphine, 2-(di-tert-butylphosphine) biphenyl, chlorinated diphenylphosphine, tris(2-tolyl)phosphine, tris(2-furyl)phosphine, tri-n-octylphosphine, bis[ (2-diphenylphosphino)phenyl]ether, 1,4-bis(diphenylphosphino)butane, 1,3-bis(diphenylphosphino)propane, acetic acid, propionic acid, trimethylacetic acid , isobutyric acid, isovaleric acid, trimethylacetic acid, preferably triphenylphosphine or trimethylacetic acid.

The solvent used in the reaction process is one or more mixed solvents in toluene, p-xylene, o-xylene, cyclohexanone, N,N-dimethylformamide or N,N-dimethylacetamide.

The present invention will be further described below through examples, the purpose of which is only to better understand the content of the present invention, rather than limit the protection scope of the present invention.

Embodiment one:

Add 0.107g (0.3mmol) of N-hexyl-4-bromo-1,8-naphthalimide and 90.9mg (0.3mmol) of 1,5-diphenyl-3-thiophene pyrazoline into a 25ml reaction tube, Pd(OAc) ₂ 3.4mg (0.015mmol), PPh 37.9mg (0.3mmol) and N,N-dimethylformamide (DMF) 2mL, stirred at 120°C for 24h under the protection of N ₂ . After the reaction, cool down, pour the product into an appropriate amount of water, extract it three times with dichloromethane, wash the dichloromethane twice with saturated brine, dry over anhydrous _MgSO4 , rotary evaporate, and use ethyl acetate/petroleum ether mixture as The eluent was passed through a silica gel column to obtain a red product. The yield is 80%; ¹ H NMR (200MHz, CDCl ₃ ), δ (ppm): 8.72 (m, 3H), 7.82 (m, 2H), 7.43 (m, 1H), 7.37 (t, 4H), 7.35 -7.33(m,5H),7.30-7.28(m,2H),6.83(t,1H),5.38(m,1H),4.20(t,2H),3.94(m,1H),3.20(m,1H ),1.76(d,2H),1.43(m,6H),0.90(t,3H); ¹³ C NMR(50MHz,CDCl ₃ ),δ(ppm):164.3,164.0,144.3,142.2,142.1,140.5, 139.1, 138.8, 132.3, 131.6, 130.9, 129.8, 129.5, 129.2, 129.0, 128.6, 128.0, 127.5, 126.6, 126.0, 123.2, 122.2, 119.7, 113.7, 64.9, 44.1, 40.2, 8, 30.3. 14.3.

The maximum emission wavelength of this compound in dichloromethane is 630nm, which is red fluorescence.

Embodiment two:

In a 25mL reaction tube, add 0.107g (0.3mmol) of N-hexyl-4-bromo-1,8-naphthalimide, 100mg (0.3mmol) of 1-phenyl-5-p-tolyl-3-thiophene pyrazoline ), Pd(OAc) ₂ 3.4mg (0.015mmol), PPh ₃ 7.9mg (0.3mmol) and N,N-dimethylformamide (DMF) 2mL, stirred at 120°C for 24h under the protection of N ₂ . After the reaction, cool down, pour the product into an appropriate amount of water, extract it three times with dichloromethane, wash the dichloromethane twice with saturated brine, dry over anhydrous _MgSO4 , rotary evaporate, and use ethyl acetate/petroleum ether mixture as The eluent was passed through a silica gel column to obtain a red product. The yield is 78%; ¹ HNMR (200MHz, CDCl ₃ ), δ (ppm): 8.68 (m, 3H), 7.81 (m, 2H), 7.56 (d, 1H), 7.40-7.31 (m, 6H), 7.19-7.14(m,4H),6.83(t,1H),5.41(m,1H),4.21(m,2H),3.83(m,1H),3.23(m,1H),2.40(s,3H) ,1.76(d,2H),1.43(m,6H),0.90(t,3H); ¹³ C NMR(50MHz,CDCl ₃ ),δ(ppm):164.3,164.0,144.3,142.2,142.1,140.5,139.1 . , 14.3.

The maximum emission wavelength of this compound in dichloromethane is 633nm, which is red fluorescence.

Embodiment three:

Add 0.107 g (0.3 mmol) of N-hexyl-4-bromo-1,8-naphthalimide, 110 mg (0.3 mmol) of 1-phenyl-5-p-chlorophenyl-3-thiophene pyrazoline into a 25 mL reaction tube mmol), Pd(OAc) ₂ 3.4mg (0.015mmol), PPh ₃ 7.9mg (0.3mmol) and N,N-dimethylformamide (DMF) 2mL, stirred at 120°C for 24h under the protection of N ₂ . After the reaction, cool down, pour the product into an appropriate amount of water, extract it three times with dichloromethane, wash the dichloromethane twice with saturated brine, dry over anhydrous _MgSO4 , rotary evaporate, and use ethyl acetate/petroleum ether mixture as The eluent was passed through a silica gel column to obtain a red product. The yield is 85%; ¹ HNMR (200MHz, CDCl ₃ ), δ (ppm): 8.72 (m, 3H), 7.82 (m, 2H), 7.54-7.08 (m, 13H), 6.83 (t, 1H), 5.38(m,1H),4.20(t,2H),3.94(m,1H),3.20(m,1H),1.76(d,2H),1.43(m,6H),0.90(t,3H); ¹³ C NMR (50MHz, CDCl ₃ ), δ (ppm): 164.3, 164.0, 144.3, 142.2, 142.2, 140.5, 139.1, 138.8, 132.3, 131.6, 130.9, 129.8, 129.5, 129.2, 129.0, 128.6, 128.0, 127. 126.6, 126.0, 123.2, 122.2, 119.7, 113.7, 64.9, 44.1, 40.8, 31.8, 28.3, 27.0, 22.8, 14.3.

The maximum emission wavelength of this compound in dichloromethane is 618nm, which is red fluorescence.

Embodiment four:

Add 0.107 g (0.3 mmol) of N-hexyl-4-bromo-1,8-naphthalimide, 110 mg (0.3 mmol) of 1-phenyl-5-methoxybenzene-3-thiophene pyrazoline into a 25 mL reaction tube mmol), Pd(OAc) ₂ 3.4mg (0.015mmol), PPh ₃ 7.9mg (0.3mmol) and N,N-dimethylformamide (DMF) 2mL, stirred at 120°C for 24h under the protection of N ₂ . After the reaction, cool down, pour the product into an appropriate amount of water, extract it three times with dichloromethane, wash the dichloromethane twice with saturated brine, dry over anhydrous _MgSO4 , rotary evaporate, and use ethyl acetate/petroleum ether mixture as The eluent was passed through a silica gel column to obtain a red product. The yield was 83%. ¹ HNMR (200MHz, CDCl ₃ ), δ (ppm): 8.73 (m, 3H), 7.81 (m, 2H), 7.54-7.08 (m, 13H), 6.82 (t, 1H), 5.36 (m, 1H) ,4.22(t,2H),3.93(m,1H),3.81(s,3H),3.22(m,1H),1.75(d,2H),1.40(m,6H),0.90(t,3H); ¹³ C NMR (50MHz, CDCl ₃ ), δ(ppm): 164.3, 164.0, 144.3, 140.5, 139.1, 138.8, 132.3, 131.6, 130.9, 129.8, 129.5, 129.2, 129.0, 128.6, 128.0, 127.5, 126.06, , 123.2, 122.2, 119.7, 113.7, 64.9, 54.2, 44.1, 40.8, 31.8, 28.3, 27.0, 22.8, 14.3.

The maximum emission wavelength of this compound in dichloromethane is 640nm, which is red fluorescence.

Claims (4)

1. A class of 1,8-naphthalimide compounds with red fluorescence, characterized in that the compound has the following general structural formula _In the _formula , R1 represents alkyl, phenyl or substituted phenyl; R2 and _R3 are alkyl, phenyl, substituted phenyl, aromatic fused ring or substituted aromatic fused ring. 2. compound as claimed in claim 1, is characterized in that, wherein R ₁ is C1-C18 alkyl, phenyl or substituted phenyl; R ₂ and R ₃ are C1-C18 alkyl, phenyl, substituted Phenyl, naphthalene, substituted naphthalene, anthracene, substituted anthracene, carbazole, substituted carbazole, fluorene, substituted fluorene, thiophene, substituted thiophene, triphenylamine, substituted triphenylamine, benzothiophene. 3. synthetic method as said compound in claim 1 or 2 is characterized in that, the main steps of said synthetic method are as follows: Mix compound II and compound III at a molar ratio of 10:1 to 1:10, add solvent and stir to dissolve, add metal catalyst, base and ligand after deoxygenation and inert gas, and react at 0-150°C for 1 to 72 hours, The solvent was distilled off, and the residue was purified to obtain the target product. The reaction equation is as follows: Wherein: the catalyst is a palladium compound and cuprous salt; the base is an inorganic base; the ligand is a phosphorus compound or a carboxylic acid compound or nothing. 4. as said synthetic method in claim 3, it is characterized in that, catalyst wherein is palladium powder, palladium carbon, palladium chloride, palladium acetate, four triphenylphosphine palladium salts, three (dibenzylidene acetone) Dipalladium, bis(triphenylphosphine)palladium chloride, benzylbis(triphenylphosphine)palladium chloride, [1,1'-bis(diphenylphosphino)ferrocene]palladium dichloride , triphenylphosphine palladium acetate, 1,4-bis(diphenylphosphinobutane) palladium dichloride, cuprous chloride, cuprous bromide, cuprous iodide, cuprous oxide; the base is cesium carbonate, Sodium carbonate, potassium carbonate, cesium acetate, sodium acetate, potassium acetate; ligands are triphenylphosphine, 2-(di-tert-butylphosphine) biphenyl, chlorodiphenylphosphine, tris(2-tolyl)phosphine, Tris(2-furyl)phosphine, tri-n-octylphosphine, bis[(2-diphenylphosphino)phenyl]ether, 1,4-bis(diphenylphosphino)butane, 1,3-bis (Diphenylphosphino)propane, acetic acid, propionic acid, trimethylacetic acid, isobutyric acid, isovaleric acid, trimethylacetic acid.