CN101486902B - Organic electroluminescent blue luminescence compound - Google Patents

Organic electroluminescent blue luminescence compound Download PDF

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CN101486902B
CN101486902B CN200910119979A CN200910119979A CN101486902B CN 101486902 B CN101486902 B CN 101486902B CN 200910119979 A CN200910119979 A CN 200910119979A CN 200910119979 A CN200910119979 A CN 200910119979A CN 101486902 B CN101486902 B CN 101486902B
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organic electroluminescent
fluoro
reaction
blue luminescence
phenyl
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CN101486902A (en
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徐茂梁
王子俊
于吉义
杜渭松
周瑞
王歌扬
肖奇
刘建韬
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Xian Modern Chemistry Research Institute
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Abstract

The invention discloses an organic electro-blue fluorescence compound; and the structure general formula is as shown below. The organic electro-blue fluorescence compound can also serve as heavy metal ion main ligand to produce electroluminescent phosphor materials.

Description

Organic electroluminescent blue luminescence compound
Technical field
The present invention is a kind of organic electroluminescent blue luminescence compound, belongs to electroluminescent organic material, is mainly used in organic electroluminescence device.
Technical background
As the blue electroluminescent fluorescent materials of the organic molecule of one of three primary colours, all receive concern widely in organic electroluminescent (OLED) field always.
The blue electroluminescent fluorescent organic micromolecule compound that contains diphenylethyllene and diphenylethyllene arylamine substitutive derivative structure is a kind of common electroluminescent fluorescent materials; One type of blue fluorescent material DSA and diphenylethyllene arylamine substitutive derivative material DSA-amine that contains the diphenylethyllene aryl is for example disclosed in the U.S. Pat 5389444,1995.DPVBi is a kind of good comprehensive properties DSA class blue fluorescent material, also is one type of more common materials of report in the document.It is with 4, and 4 '-dichloromethyl biphenyl and UVNUL MS-40 carry out that the wittig coupling makes.Nineteen ninety-five, it is the OLED device of luminescent layer with DPVBi that the research group of Kusumoto T. has made, obtained good effect (Hosokawa C, Tokailin H, Higashi H, et al.J.Appl.Phys.Lett.1995,78:5831).DSA, DSA-amine, the structure of DPVBi is as follows:
At present, the kind of the higher organic electroluminescent blue luminescence material of fluorescence quantum efficiency is still less.
Summary of the invention
Technical problem to be solved by this invention is to overcome disadvantages of background technology, provides a kind of fluorescence quantum efficiency higher organic electroluminescent blue luminescence compound.
General structure of the present invention is following:
Figure G2009101199793D00021
Wherein
The preferred compound of the present invention, its structural formula is as follows:
Figure G2009101199793D00023
Wherein
Figure G2009101199793D00024
The present invention's second preferred compound, its structural formula is as follows:
Wherein
Figure G2009101199793D00031
The tape base R that gets of the present invention can also be other aromatic group except that above-mentioned two kinds, synthetic a series of organic electroluminescent blue luminescence compounds, and its structural formula is as follows:
Figure G2009101199793D00032
Advantage of the present invention:
1, the fluorescence quantum efficiency of organic electroluminescent blue luminescence material of the present invention is higher, and its fluorescence quantum efficiency can reach 8.0 times of DPVBi;
2, pyridine heterocycle can form title complex with heavy metal ion in the structure of the present invention, thereby the present invention can further prepare organic electromechanical phosphorescent material.
Synthetic route of the present invention is:
Embodiment
Synthesizing of embodiment 1:E-1-(4-hexichol aminocarbonyl phenyl)-2-(2-fluoro-4-(2 '-pyridyl) phenyl) ethene
1.1 synthetic route: the present invention implements with reference to following synthetic route.
Figure G2009101199793D00042
1.2 synthesis step
(1) 2-fluoro-4-bromo-bromotoluene is synthetic
In the reaction flask of being furnished with mechanical stirring and reflux condensing tube, add 75.6g (0.4mol) 2-fluoro-4 toluene bromides and 14.4g Lucidol; After being heated to backflow under stirring; With 71.2g (0.4mol) 2-bromo-2; 5-pyrroledione (NBS) added reaction flask in batches in 20 minutes, reflux 2 hours, reaction yield 65% (GC).
Reaction solution adds the yellow soda ash neutralization, concentrates, and (1g: 1mL) backflow dissolving is cooled to-15 ℃ and carries out recrystallization, about 90% (GC) of purity with industry anhydrous ethanol.Its purity＞99% behind the recrystallization repeatedly.
(2) 4-pentanoic benzaldehyde is synthetic
Under the nitrogen protection, in the reaction flask of being furnished with mechanical stirring and reflux condensing tube, add 12.3g (0.05mol) triphenylamine, 100mL DMF; Be cooled to 5 ℃ in the ice bath, stir and slowly drip POCl3 18.5g (0.1mol) down, after being added dropwise to complete; Remove ice bath, rise to room temperature after 1 hour.Reflux 12 hours.
Reaction solution adds 100mL water, divides with 400mL ETHYLE ACETATE to extract for 4 times again, and organic phase merges, and washing is to neutral, anhydrous magnesium sulfate drying, remove ETHYLE ACETATE after, silica gel chromatography gets white solid, isolated yield 62%.
(3) E-1-(4-hexichol aminocarbonyl phenyl)-2-(2-fluoro-4-bromophenyl) ethene is synthetic
Under the nitrogen protection, in the reaction flask of being furnished with mechanical stirring and reflux condensing tube, add 8.0g (0.03mol) 2-fluoro-4-bromo-bromotoluene, 15g (0.09mol) triethyl-phosphite is heated to backflow under stirring, and reacts 1 hour.After reaction stopped, underpressure distillation went out excessive triethyl-phosphite.After distillation is accomplished, be cooled to room temperature, with cooling reaction temperature to 5 in the ice bath ℃.Keeping temperature of reaction is 5 ℃, in 20 minutes, adds 3.5g (0.03mol) potassium tert.-butoxide in batches, reacts after 1 hour, drips the THF solution 35mL that contains 7.5g (0.03mol) 4-pentanoic benzaldehyde, reacts 2 hours.
Reaction solution adds 100mL water and 100mL methylene dichloride, and separatory, water are used the 100mL dichloromethane extraction again; After merging organic phase and water and a small amount of Hydrogen chloride were washed till neutrality, anhydrous magnesium sulfate drying was removed methylene dichloride; Silica gel chromatography gets yellow solid, isolated yield 45%.
(4) E-1-(4-hexichol aminocarbonyl phenyl)-2-(2-fluoro-4-(2 '-pyridyl) phenyl) ethene is synthetic
Under the nitrogen protection; In the reaction flask of being furnished with mechanical stirring, reflux condensing tube, add 4.4g (0.01mol) E-1-(4-hexichol aminocarbonyl phenyl)-2-(2-fluoro-4-bromophenyl) ethene, 4.5g (0.012mol) 2-(tributyl tinbase) pyridine, 3%mol four (triphenylphosphinyl) palladium; 50mL toluene; Stir, be heated to backflow, reacted 48 hours.
Reaction solution is dry under vacuum, adds the dissolving of 100mL methylene dichloride, divides three washings with 6M hydrochloric acid 60mL; Water neutralizes with 10% ammoniacal liquor under the state of cooling; Use the 100mL dichloromethane extraction again, merge organic phase, add 50mL water and extremely neutral with 10% ammonia scrubbing.Collect organic phase, drying is crossed silica gel column chromatography and is purified, and gets yellow solid, isolated yield 43%.
1.3 structure is identified
Ir spectra (KBr, cm -1): 3034,1274 (C=C-H), 1628 (C=C), 1587,1556,1491,1461 (aromatic ring C=C), 972 (trans dihydros), 899,833,778,751,694 (aromatic ring C-H), 1315 (C-N), 990 (C-F)
Magnetic resonance spectroscopy: δ (ppm), 8.744-8.753 (d, 1H, J=4.5Hz), 7.889 (s, 1H), 7.830-7.845 (d, 1H; J=7.5Hz), 7.764 (s, 1H), 7.674-7.691 (d, 1H, J=8.5Hz), 7.519-7.535 (d, 1H; J=8.0Hz), 7.396-7.439 (m, 2H), 7.341 (s, 1H), 7.248-7.280 (m, 4H), 7.174-7.207 (d; 1H, J=16.5Hz, trans olefins), 7.112-7.127 (d, 4H, J=7.5Hz), 7.019-7.069 (m, 4H)
Ultimate analysis: actual measurement C:83.91, N:6.25, H:5.30
Theoretical C:84.14, N:6.33, H:5.24
Mass spectrum: M/Z 441 (M+)
The above-mentioned reaction gained of above data acknowledgement compound is E-1-(4-hexichol aminocarbonyl phenyl)-2-(2-fluoro-4-(2 '-pyridyl) phenyl) ethene.Through measuring, the fusing point of this material is 160-162 ℃.
1.4 optical property qualitative test
Uv-visible absorption spectra: measure with UNICO UV-2102PCS type ultraviolet-visible pectrophotometer, recording the uv-visible absorption spectra peak wavelength is 391nm.
Fluorescence spectrum: with 970CRT type fluorescent spectrophotometer assay, recording the fluorescence spectrum peak wavelength is 499nm, belongs to the blue green light category.
1.5 relative fluorescence quantum yield test
Accurately take by weighing 79.7mg DPVBi, the dried 25mL volumetric flask of 69.1mg E-1-(4-hexichol aminocarbonyl phenyl)-2-(2-fluoro-4-(2 '-pyridyl) phenyl) second rare (being numbered U1) respectively, add the methylene dichloride dissolving and also be diluted to scale.Get the 1mL solution dilution respectively to 25mL, the solution after will diluting is respectively respectively got 1mL and is diluted to 25mL, obtains 1.0 * 10 -5Two kinds of solution of M.
Measure with UNICO UV-2102PCS type ultraviolet-visible pectrophotometer, two solution are identical in the absorption at 324nm place, are 0.278 (Abs).
With 324nm is excitation wavelength, and with the luminous intensity of 970CRT type fluorescent spectrophotometer assay two solution, sensitivity is 2, and the exciting light slit is 5nm, and the emission optical slits is 5nm, and two fluorescent spectrum curve integrated values are respectively:
DPVBi:F S=3279.108,348.8nm-571.7nm, peak value are 448nm;
U1:F U1=26184.394,404.5nm-639.4nm, peak value are 499nm.
Because two solution have same concentrations and identical absorbancy, according to formula:
Ψ U = F U F S Ψ S (wherein Ψ represents fluorescence quantum efficiency, and F represents the fluorescent spectrum curve integrated value, and footmark U and S represent test substance and reference material respectively)
Get Ψ U=8.0 Ψ S, promptly the fluorescence quantum efficiency of E-1-(4-hexichol aminocarbonyl phenyl)-2-(2-fluoro-4-(2 '-pyridyl) phenyl) ethene (being numbered U1) is 8.0 times of DPVBi.
Synthesizing of embodiment 2:E-1-(3-(N-ethyl carbazole base))-2-(2-fluoro-4-(2 '-pyridyl) phenyl) ethene
2.1 synthetic route: the present invention implements with reference to following synthetic route
2.2 synthesis step
(1) 3-(N-ethyl carbazole base) formaldehyde is synthetic
Under the nitrogen protection, in the reaction flask of being furnished with mechanical stirring and reflux condensing tube, add 11.8g (0.06mol) N-ethyl carbazole, 100mL DMF; Temperature of reaction is reduced to 5 ℃, begins to stir, and slowly drips POCl3 22g (0.12mol); Be added dropwise to complete the back and remove ice bath, rise to room temperature after 1 hour.Reflux 12 hours.
Reaction solution adds 100mL water, divides with 400mL ETHYLE ACETATE to extract for 4 times again, and organic phase merges, and washes to neutral, and anhydrous magnesium sulfate drying is removed ETHYLE ACETATE, crosses silica gel column chromatography and purifies, and gets white solid, isolated yield 75%.
(2) E-1-(3-(N-ethyl carbazole base))-2-(2-fluoro-4-bromophenyl) ethene is synthetic
Under the nitrogen protection, in the reaction flask of being furnished with mechanical stirring and reflux condensing tube, add 6.9g (0.025mol) 2-fluoro-4-bromo-bromotoluene, 13.0g (0.075mol) triethyl-phosphite stirs, and is heated to backflow, reacts 1 hour.After reaction stopped, underpressure distillation went out excessive triethyl-phosphite.Distillation is cooled to room temperature after accomplishing, and temperature of reaction is reduced to 5 ℃.Keeping temperature of reaction is 5 ℃, after in 20 minutes, adding 3.0g (0.025mol) potassium tert.-butoxide in batches and reacting 1 hour, drips the THF solution 30mL that contains 5.4g (0.025mol) 3-(N-ethyl carbazole base) formaldehyde, reacts 2 hours.
Reaction solution adds 100mL water and 100mL methylene dichloride, and separatory, water are again with the 100mL dichloromethane extraction; Merge organic phase and water and a small amount of Hydrogen chloride and be washed till neutrality, anhydrous magnesium sulfate drying is removed methylene dichloride; Silica gel chromatography gets yellow solid, isolated yield 44%.
(3) E-1-(3-(N-ethyl carbazole base))-2-(2-fluoro-4-(2 '-pyridyl) phenyl) ethene is synthetic
Under the nitrogen protection; In the reaction flask of being furnished with mechanical stirring, reflux condensing tube, add 4.0g (0.01mol) E-1-(3-(N-ethyl carbazole base))-2-(2-fluoro-4-(2 '-pyridyl) phenyl) ethene; 4.5g (0.012mol) 2-(tributyl tinbase) pyridine, 3%mol four (triphenylphosphinyl) palladium, 50mL toluene; Stir reflux 48 hours.
Reaction solution is dry under vacuum, adds the dissolving of 100mL methylene dichloride, divides three washings with 6M hydrochloric acid 60mL; Water neutralizes with 10% ammoniacal liquor under the state of cooling; Use the 100mL dichloromethane extraction again, merge organic phase, add 50mL water and extremely neutral with 10% ammonia scrubbing.Collect organic phase, drying is removed methylene dichloride, and silica gel column chromatography is purified, and gets yellow solid, isolated yield 41%.
2.3 structure is identified
Ir spectra (KBr, cm -1): 3043,1232 (C=C-H), 2980,1377 (CH 3), 2933,1463,718 (CH 2), 1624 (C=C), 1585,1575,1554,1441 (aromatic ring C-C), 963 (trans dihydros), 903,800,774,750 (aromatic ring C-H), 1308 (C-N), 989 (C-F)
Magnetic resonance spectroscopy: δ (ppm), and 8.620-8.629 (d, 1H, J=4.5Hz), 8.191-8.194 (d, 1H, J=1.5Hz); 8.054-8.069 (d, 1H, J=7.5Hz), 7.628-7.742 (m, 6H), 7.372-7.420 (m, 2H); 7.306-7.339 (t, 2H, J=8.3Hz), 7.245-7.278 (d, 1H, J=16.5Hz trans olefins), 7.151-7.196 (m; 2H), and 4.267-4.311 (q, 2H, J=7.4Hz), 1.354-1.383 (t, 3H, J=7.3Hz)
Ultimate analysis: actual measurement C:82.75, N:7.08, H:5.47;
Theoretical C:82.63, N:7.14, H:5.39.
Mass spectrum: M/Z 391 (M+)
The above-mentioned reaction gained of above data acknowledgement compound is E-1-(3-(N-ethyl carbazole base))-2-(2-fluoro-4-(2 '-pyridyl) phenyl) ethene.Through measuring, the fusing point of this material is 124-126 ℃.
2.4 optical property qualitative test
Uv-visible absorption spectra: measure with UNICO UV-2102PCS type ultraviolet-visible pectrophotometer, recording the uv-visible absorption spectra peak wavelength is 360nm.
Fluorescence spectrum: with 970CRT type fluorescent spectrophotometer assay, recording the fluorescence spectrum peak wavelength is 464nm, belongs to the blue light category.
2.5 relative fluorescence quantum yield test
Accurately take by weighing 79.7mg DPVBi, 61.3mg E-1-(3-(N-ethyl carbazole base))-2-(2-fluoro-4-(2 '-pyridyl) phenyl) ethene (being numbered U2) respectively in the 25mL volumetric flask, add the methylene dichloride dissolving and be diluted to scale.Get the 1mL solution dilution respectively to 25mL, the solution after will diluting is respectively respectively got 1mL and is diluted to 25mL, obtains 1.0 * 10 -5Two kinds of solution of M.
Measure with UNICO UV-2102PCS type ultraviolet-visible pectrophotometer, two solution are identical in the absorption at 318nm place, are 0.227 (Abs).
With 318nm is excitation wavelength, and with the luminous intensity of 970CRT type fluorescent spectrophotometer assay two solution, sensitivity is 3, and the exciting light slit is 5nm, and the emission optical slits is 5nm, and two fluorescent spectrum curve integrated values are respectively:
DPVBi:F S=23137.346,340.0nm-596.3nm, peak value are 448nm;
U2:F U2=64244.492,340.0nm-620.4nm, peak value are 464nm.
Because two solution have same concentrations and identical absorbancy, according to formula:
Ψ U = F U F S Ψ S (wherein Ψ represents fluorescence quantum efficiency, and F represents the fluorescent spectrum curve integrated value, and footmark U and S represent test substance and reference material respectively)
Get Ψ U=2.8 Ψ S, promptly the fluorescence quantum efficiency of E-1-(3-(N-ethyl carbazole base))-2-(2-fluoro-4-(2 '-pyridyl) phenyl) ethene (being numbered U2) is 2.8 times of DPVBi.

Claims (3)

1. organic electroluminescent blue luminescence compound, its general structure is following:
Figure FSB00000746968400011
Wherein
Figure FSB00000746968400012
2. organic electroluminescent blue luminescence compound according to claim 1 is characterized in that structural formula is following:
Figure FSB00000746968400013
3. organic electroluminescent blue luminescence compound according to claim 1 is characterized in that structural formula is following:
Figure FSB00000746968400014
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CN102127010B (en) * 2010-12-29 2013-06-12 太原理工大学 Preparation method of greenish yellow light-emitting material using pyridine as donor unit
CN103833735B (en) * 2014-02-26 2016-07-06 贵州省果树科学研究所 A kind of compound preventing and treating downy mildew of garpe and apply its compositions
CN105348295A (en) * 2015-09-25 2016-02-24 西安近代化学研究所 Polymer monomer used for stable blue phase liquid crystal and synthesis method

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US5389444A (en) * 1991-09-18 1995-02-14 Idemitsu Kosan Co., Ltd. Organic electroluminescence device

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5389444A (en) * 1991-09-18 1995-02-14 Idemitsu Kosan Co., Ltd. Organic electroluminescence device

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