1. The room-temperature phosphorescent material has a chemical structure as shown in any one of formulas I1-I3:

in the formula I1, R₁～R₅Independently is H, F, Cl, Br, I or

In the formulas I2-I3, R₁～R₁₀Independently is H, F, Cl, Br, I orAnd the number of the first and second electrodes,R₁～R₅at least one isOr R₆～R₁₀At least one is

2. The room temperature phosphorescent material of claim 1, wherein in the formula I1, R is₁～R₅Independently is H, F, Cl, Br, I orAnd, R₂～R₄At least one is

In the formulas I2-I3, R₁～R₁₀Independently is H, F, Cl, Br, I orAnd, R₅And R₈At least one of them is

3. A method for preparing a room temperature phosphorescent material as claimed in claim 1 or 2, comprising:

dissolving a halogenated phenyl compound, morpholine, an alkaline reagent, a catalyst and a ligand in a solvent, and carrying out Ullmann reaction to obtain the room-temperature phosphorescent material.

4. The method of claim 3, wherein the halogenated phenyl compound comprises a halogenated benzene, a halogenated phenylene sulfide, or a halogenated phenylene ether.

5. The method of claim 3, wherein the basic agent comprises sodium tert-butoxide, potassium tert-butoxide, or potassium carbonate.

6. The method of claim 3, wherein the catalyst comprises tris (dibenzylideneacetone) dipalladium, palladium acetate, or cuprous iodide.

7. The method of claim 3, wherein the ligand comprises tris (o-methylphenyl) phosphorus, trans-cyclohexanediamine, or (±) -2,2 '-bis- (diphenylphosphino) -1,1' -binaphthyl.

8. The production method according to claim 3, wherein the ratio of the amounts of the substituents, morpholine, the basic agent, the catalyst and the ligand in the halogenated benzene is 1: (1-6): (1-8): (0.001-0.06): (0.005-0.1).

9. The preparation method according to claim 3, wherein the Ullmann reaction temperature is 90-110 ℃ and the Ullmann reaction time is 24-36 h.

10. The room temperature phosphorescent material according to claim 1 or 2 or the room temperature phosphorescent material prepared by the preparation method according to any one of claims 3 to 9 is applied to an organic electroluminescent device.

Background

Due to the presence of spin multiplicities, the light-emitting material can emit short-lived fluorescence through a singlet state and long-lived phosphorescence through a triplet state. However, since triplet excitons are very sensitive to oxygen and temperature, this severely hinders the emission of phosphorescence at room temperature and limits the development of phosphorescent materials. The phosphorescent material containing noble metal has strong intersystem crossing capability and easier phosphorescent emission due to heavy atom effect, but the further development of the material is limited due to the problems of high price, high toxicity, serious environmental pollution, poor processability and the like. Compared with metal-containing phosphorescent materials, pure organic phosphorescent materials are widely researched due to the advantages of low cost, easiness in modification, simplicity in synthesis, capability of being specifically designed according to different purposes, small environmental pollution and the like. However, pure organic room temperature phosphorescent materials are still rare at present, and mainly due to weak spin-orbit coupling, triplet excitons are difficult to generate, energy loss caused by vibration and rotation of molecules and quenching of phosphorescence caused by temperature, oxygen and the like. Therefore, how to develop the pure organic room temperature phosphorescent material through molecular design has important research significance and value in the aspects of theory and application research.

In recent years, the Tang faith team successfully obtained Room Temperature phosphorescent materials by controlling the acting force between molecules to reduce the energy loss caused by the rotation of the molecular vibration (Wei P, Zhang X, Liu J, et al.New Wine in Old botters: growing Room-Temperature phosphorescent emission of Crown Ethers by superior phosphorescent interaction [ J ]. Angewandte chemical interaction, 2020,59.), and then realized Room Temperature phosphorescent emission by host-object doping (Zhang X, Du L, Zhao W, et al.Uralong UV/mechanical-excited phosphorescent emission [ J ]. Communication, 2019, 20110 (5161): 1). However, these systems have the problem of short material life, for example, the material life is within microseconds, which limits the application of the system in data anti-counterfeiting encryption and other aspects. Therefore, the development of a pure organic room temperature phosphorescent material with long service life is a key scientific problem to be solved urgently in the field of current organic luminescent materials.

Disclosure of Invention

The invention aims to provide a room temperature phosphorescent material with long phosphorescence emission life.

In order to achieve the above object, the present invention provides the following technical solutions:

the invention provides a room-temperature phosphorescent material, which has a chemical structure shown in any one of formulas I1-I3:

in the formula I1, R₁～R₅Independently is H, F, Cl, Br, I orAnd, R₁～R₅At least one is

In the formulas I2-I3, R₁～R₁₀Independently is H, F, Cl, Br, I orAnd, R₁～R₅At least one isOr R₆～R₁₀At least one is

Preferably, in said formula I1, R₁～R₅Independently is H, F, Cl, Br, I orAnd, R₂～R₄At least one is

In the formulas I2-I3, R₁～R₁₀Independently is H, F, Cl, Br, I orAnd, R₅And R₈At least one of them is

The invention also provides a preparation method of the room temperature phosphorescent material, which comprises the following steps:

dissolving a halogenated phenyl compound, morpholine, an alkaline reagent, a catalyst and a ligand in a solvent, and carrying out Ullmann reaction to obtain the room-temperature phosphorescent material.

Preferably, the halogenated phenyl compound comprises a halogenated benzene, a halogenated phenylene sulfide, or a halogenated phenylene ether.

Preferably, the basic agent comprises sodium tert-butoxide, potassium tert-butoxide or potassium carbonate.

Preferably, the catalyst comprises tris (dibenzylideneacetone) dipalladium, palladium acetate or cuprous iodide.

Preferably, the ligand comprises tris (o-methylphenyl) phosphorus, trans-cyclohexanediamine or (±) -2,2 '-bis- (diphenylphosphino) -1,1' -binaphthyl.

Preferably, the ratio of the amounts of the halogenated benzene, morpholine, alkaline agent, catalyst and ligand is 1: (1-6): (1-8): (0.001-0.06): (0.005-0.1).

Preferably, the temperature of the Ullmann reaction is 90-110 ℃, and the time of the Ullmann reaction is 24-36 h.

The invention also provides the application of the room temperature phosphorescent material in the technical scheme or the room temperature phosphorescent material prepared by the preparation method in the technical scheme in an organic electroluminescent device.

The invention provides a room-temperature phosphorescent material which has a chemical structure as shown in any one of formulas I1-I3. The invention uses morpholine to completely or partially substitute halogenated phenyl compounds, introduces heteroatom (morpholine) into molecules to enhance the generation of triplet excitons, and the heteroatom forms interaction between molecules, such as C-H … O and C-H … pi, the interaction enables the energy loss caused by the vibration and rotation of the molecules to be obviously reduced, thereby inhibiting the energy loss caused by molecular non-radiative transition, being beneficial to phosphorescence emission and obtaining the room temperature phosphorescent material with longer service life. Experimental results show that the room-temperature phosphorescent material provided by the invention has the characteristic of phosphorescence emission, and the phosphorescence emission life of the room-temperature phosphorescent material can reach 1037 milliseconds, which is far longer than that of the room-temperature phosphorescent material in most of the prior art.

Drawings

FIG. 1 is a fluorescence emission spectrum at room temperature and a phosphorescence emission spectrum delayed by 1ms of 4-phenylmorpholine used in example 1;

FIG. 2 is a life decay curve of 4-phenylmorpholine used in example 1;

FIG. 3 is a fluorescence emission spectrum and a phosphorescence emission spectrum delayed by 1ms of 1, 4-dimorpholinobenzene prepared in example 2 at room temperature;

FIG. 4 is a life decay curve of 1, 4-dimorpholinobenzene prepared in example 2;

FIG. 5 is a fluorescence emission spectrum and a phosphorescence emission spectrum delayed by 1ms of 1,3, 5-trimorpholine benzene prepared in example 3 at room temperature;

FIG. 6 is a life decay curve of 1,3, 5-trimorpholinobenzene prepared in example 3;

FIG. 7 is a fluorescence emission spectrum of 1,2,4, 5-tetramorpholinobenzene prepared in example 4 at room temperature and a phosphorescence emission spectrum delayed by 1 ms;

FIG. 8 is a graph showing the lifetime decay of 1,2,4, 5-tetramorpholinobenzene prepared in example 4;

FIG. 9 is a fluorescence emission spectrum and a phosphorescence emission spectrum delayed by 1ms of 4- (4-bromobenzene) morpholine prepared in example 5 at room temperature;

FIG. 10 is a life time decay curve of 4- (4-bromobenzene) morpholine prepared in example 5;

FIG. 11 is a fluorescence emission spectrum and a phosphorescence emission spectrum delayed by 1ms of bis (4-phenylmorpholine) sulfide prepared in example 6 at room temperature;

FIG. 12 is a life time decay curve of bis (4-phenylmorpholine) sulfide prepared in example 6;

FIG. 13 is a fluorescence emission spectrum and a phosphorescence emission spectrum delayed by 1ms of bis (4-phenylmorpholine) ether prepared in example 7 at room temperature;

FIG. 14 is a life time decay curve of bis (4-phenylmorpholine) ether prepared in example 7.

Detailed Description

The invention provides a room-temperature phosphorescent material, which has a chemical structure shown in any one of formulas I1-I3:

in the formula I1, R₁～R₅Independently is H, F, Cl, Br, I orIn the formulas I2-I3, R₁～R₁₀Independently is H, F, Cl, Br, I orAnd, R₁～R₅At least one isOr R₆～R₁₀At least one is

In the invention, in the formula I1, R₁～R₅Independently preferably H, F, Cl, Br, I orWherein R is₂～R₄At least one isMore preferably one or more of 1, 4-dimorpholinobenzene, 1,3, 5-trimorpholinobenzene, 1,2,4, 5-tetramorpholinobenzene and 4- (4-bromobenzene) morpholine.

In the invention, in the formula I2, R₁～R₁₀Independently preferably H, F, Cl, Br, I orWherein R is₅And R₈At least one of them isMore preferably R₅And R₈At the same time are

In the invention, R in the formula I3₁～R₁₀Independently preferably H, F, Cl, Br, I orWherein R is₅And R₈At least one of them isMore preferably R₅And R₈At the same time are

The room temperature phosphorescent material provided by the invention utilizes morpholine to completely or partially substitute a halogenated phenyl compound, heteroatom (morpholine) is introduced into molecules to enhance the generation of triplet excitons, and the heteroatom forms interaction between the molecules, such as C-H … O and C-H … pi, the interaction enables the energy loss caused by the vibration and rotation of the molecules to be obviously reduced, so that the energy loss caused by non-radiative transition of the molecules is inhibited, the phosphorescence emission is facilitated, and the room temperature phosphorescent material with longer service life is obtained.

The invention also provides a preparation method of the room temperature phosphorescent material, which comprises the following steps: dissolving a halogenated phenyl compound, morpholine, an alkaline reagent, a catalyst and a ligand in a solvent, and carrying out Ullmann reaction to obtain the room-temperature phosphorescent material.

In the present invention, the halogenated phenyl compound preferably includes halogenated benzene, halogenated phenylene sulfide or halogenated phenylene ether. The source of the halophenyl compound in the present invention is not particularly limited, and commercially available products known to those skilled in the art may be used. In the invention, when the room temperature phosphorescent material has a structure shown as formula I1, the halogenated phenyl compound is halogenated benzene; when the room-temperature phosphorescent material has a structure shown as formula I2, the halogenated phenyl compound is halogenated phenyl sulfide; when the room temperature phosphorescent material has a structure shown in formula I3, the halogenated phenyl compound is halogenated phenyl ether.

In the present invention, the number of halogen atoms in the halophenyl compound determines the heteroatom introduced into the prepared room temperature phosphorescent materialBy controlling the amount of the heteroatom introduced, a longer-lived room temperature phosphorescent material is obtained.

In the invention, the morpholine provides a heteroatom for preparing the room temperature phosphorescent material. The source of morpholine in the present invention is not particularly limited, and commercially available products known to those skilled in the art may be used.

In the present invention, the basic agent preferably includes sodium tert-butoxide, potassium tert-butoxide or potassium carbonate, more preferably sodium tert-butoxide. The source of the alkaline agent is not particularly limited in the present invention, and commercially available products known to those skilled in the art may be used. In the invention, the alkaline reagent can provide an alkaline environment for the Ullmann reaction and promote the Ullmann reaction to smoothly proceed.

In the present invention, the catalyst preferably comprises tris (dibenzylideneacetone) dipalladium, palladium acetate or cuprous iodide. The source of the catalyst in the present invention is not particularly limited, and commercially available products known to those skilled in the art may be used. In the present invention, the presence of the catalyst promotes smooth progress of the ullmann reaction.

In the present invention, the ligand preferably includes tris (o-methylphenyl) phosphorus, trans-cyclohexanediamine, or (±) -2,2 '-bis- (diphenylphosphino) -1,1' -binaphthyl. The source of the ligand is not particularly limited in the present invention, and commercially available products known to those skilled in the art may be used. In the present invention, the ligand can stabilize a compound which is easily reacted and prevent the formation of excessive impurities.

In the present invention, the solvent preferably includes toluene, o-xylene or dioxane, more preferably toluene. The source of the solvent is not particularly limited in the present invention, and a commercially available product known to those skilled in the art may be used. The dosage of the solvent is not specially limited, and the solvent is determined according to the dosage of reactants, so that the reactants can be completely dissolved.

In the present invention, the ratio of the amounts of the substance of the halophenyl compound, morpholine, basic agent, catalyst and ligand is preferably 1: (1-6): (1-8): (0.001-0.06): (0.005-0.1). In the present invention, when the ratio of the amounts of the halogenated phenyl compound, morpholine, the basic agent, the catalyst and the ligand is in the above range, the catalytic reaction is more advantageously promoted, and the yield of the reaction product is higher.

The halogenated phenyl compound, morpholine, an alkaline reagent, a catalyst and a ligand are dissolved in a solvent to obtain a reaction solution. The operation of dissolving the halogenated phenyl compound, morpholine, alkaline reagent, catalyst and ligand in the solvent is not particularly limited in the present invention, and the operation of dissolving solid in liquid, which is well known to those skilled in the art, can be adopted.

After reaction liquid is obtained, the invention carries out Ullmann reaction on the reaction liquid to obtain the room temperature phosphorescent material.

In the invention, the preferred temperature of the Ullmann reaction is 90-110 ℃, and more preferred temperature is 100-110 ℃; the time of the Ullmann reaction is preferably 24 to 36 hours, and more preferably 25 to 30 hours. In the present invention, when the temperature and time of the ullmann reaction are within the above ranges, the ullmann reaction is more advantageously performed.

In the present invention, the Ullmann reaction is preferably carried out under stirring. The stirring speed is not particularly limited, and the reaction liquid can be swirled at the center. In the invention, the stirring can promote the uniform mixing of all components in the reaction liquid, and is favorable for promoting the Ullmann reaction.

After the Ullmann reaction is finished, the invention preferably purifies the product of the Ullmann reaction to obtain the room-temperature phosphorescent material. In the present invention, the purification preferably includes extraction, column chromatography and recrystallization, which are sequentially performed. The extraction, column chromatography and recrystallization operations are not particularly limited in the present invention, and the extraction, column chromatography and recrystallization operations known to those skilled in the art may be used.

In the present invention, the solvent for the extraction is preferably water and dichloromethane; the volume of the water is preferably the same as that of a product obtained by the Ullmann reaction, and the volume ratio of the dichloromethane to the water is preferably (3-5): 1. In the present invention, when the type and amount of the solvent for extraction are within the above-mentioned ranges, the product of the ullmann reaction can be roughly purified.

In the invention, the solvent adopted by the column chromatography is preferably petroleum ether and ethyl acetate, and the volume ratio of the petroleum ether to the ethyl acetate is preferably 1: 2-1: 9, and more preferably 1: 5-1: 8. In the invention, when the solvent adopted by the column chromatography is of the type mentioned above, impurities can be removed, incomplete separation of products can be prevented, and further purification of the crude purified products can be realized.

The present invention preferably subjects the crude purified product to solvent evaporation prior to column chromatography. The solvent evaporation method of the present invention is not particularly limited, and a solvent evaporation method known to those skilled in the art may be used. In the present invention, the operation of the solvent evaporation is preferably evaporation under reduced pressure. In the invention, the pressure during the reduced pressure evaporation is preferably 15-35 mmhg; the temperature of the reduced pressure evaporation is preferably 40-50 ℃, and more preferably 45-50 ℃; the time of the reduced pressure evaporation is preferably 1-2 h. In the invention, the solvent in the crude purified product can be removed by carrying out solvent evaporation before column chromatography on the extracted product before column chromatography, and a subsequent column chromatography purification process is further utilized.

In the present invention, the solvent used for the recrystallization is preferably ethanol. The source of the ethanol is not particularly limited in the present invention, and commercially available products known to those skilled in the art may be used. In the present invention, the ethanol can facilitate recrystallization of the further purified product, resulting in a room temperature phosphorescent material with high purity.

After the recrystallization is finished, the invention preferably carries out solid-liquid separation and drying on the recrystallized product in sequence to obtain the room temperature phosphorescent material. The operation of the solid-liquid separation is not particularly limited, and the solid obtained by recrystallization can be separated from ethanol. In the present invention, the operation of the solid-liquid separation is preferably filtration. The apparatus used for the drying in the present invention is not particularly limited, and any apparatus known to those skilled in the art may be used. In the present invention, the apparatus used for drying is preferably an oven. In the invention, the temperature required for drying the solid after solid-liquid separation is preferably 60-100 ℃, and more preferably 80-90 ℃; the drying time is preferably 12 to 24 hours, and more preferably 18 to 20 hours. In the invention, the product obtained by recrystallization can be separated from ethanol by sequentially carrying out solid-liquid separation and drying on the product obtained by recrystallization, so as to obtain the room-temperature phosphorescent material.

The method provided by the invention dissolves a halogenated phenyl compound, morpholine, an alkaline reagent, a catalyst and a ligand in a solvent to carry out Ullmann reaction, and obtains the room temperature phosphorescent material with higher purity by controlling the mass ratio of substances and the reaction condition of each substance, wherein the room temperature phosphorescent material introduces heteroatoms in molecules to enhance the generation of triplet excitons, and the heteroatoms can form interaction among the molecules so as to inhibit the energy loss caused by molecular non-radiative transition and be beneficial to phosphorescence emission.

The invention provides the application of the room temperature phosphorescent material in the technical scheme or the room temperature phosphorescent material prepared by the preparation method in the technical scheme in an organic electroluminescent device. The method for applying the room temperature phosphorescent material in the organic electroluminescent device is not particularly limited in the invention, and the application method known to those skilled in the art can be adopted.

In the invention, the room temperature phosphorescent material provided by the invention is a room temperature phosphorescent material with a long service life, has strong luminescence property and long luminescence service life, can achieve afterglow visible to naked eyes for 1-8 seconds, has a wide color adjustable range, can have a full visible spectrum from purple to yellow green, and can be used in an organic electroluminescent device.

The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The 4-phenylmorpholine used in this example is a commercially available product,¹H NMR(500MHz,CD₂Cl₂)δ7.30(t,J＝7.7Hz,2H),6.95(d,J＝8.0Hz,2H),6.89(t,J＝7.2Hz,1H),3.86(t,4H),3.16(t,4H)。

the fluorescence test of 4-phenylmorpholine used in this example is shown in FIG. 1, which shows the fluorescence emission spectrum at room temperature with a 1ms delay. As can be seen from fig. 1, the emission peak of morpholine still exists after 1ms delay, which indicates that the material has phosphorescent emission at room temperature.

The lifetime decay curve obtained by performing the lifetime decay test on 4-phenylmorpholine used in this example is shown in FIG. 2. It can be seen from fig. 2 that the phosphorescence emission peak is the lifetime in the order of milliseconds, which demonstrates that the emission at this wavelength is phosphorescence emission. The phosphorescent emission lifetime was calculated to be 458.91 ms using multiple exponential fits according to fig. 2.

Example 2

Adding 1, 4-dibromobenzene (1.2g, 10mmol), morpholine (1g, 24mmol), sodium tert-butoxide (1.25g, 13.0mmol), tris (dibenzylideneacetone) dipalladium (0.0575g, 0.06279mmol) and tris (o-methylphenyl) phosphorus (0.061g, 0.2mmol) into a toluene (30mL) solvent, stirring at 100 ℃ for 24h, extracting with water and dichloromethane (the volume ratio of the two is 1:3) after the reaction is finished, and purifying the obtained solid product by chromatography after the solvent is evaporated under reduced pressure, wherein the chromatography liquid is petroleum ether/ethyl acetate 1: 8. Recrystallization from absolute ethanol and vacuum drying gave 1.62g of a white powder, i.e. 1, 4-dimorpholinobenzene, room temperature phosphor in 65% yield. 1HNMR (500MHz, CD2Cl2) delta 6.91(s,1H),3.85(s,2H),3.07(s, 2H).

Fluorescence tests were performed on the 1, 4-dimorpholinobenzene prepared in this example, and the fluorescence emission spectrum at room temperature, the phosphorescence emission spectrum after 1 millisecond delay, and the lifetime decay curve obtained are shown in fig. 3. As can be seen from FIG. 3, the 1, 4-dimorpholinobenzene prepared in this example still has an emission peak after a delay of 1ms, which indicates that the material has phosphorescent emission at room temperature.

The lifetime decay curve obtained by performing the lifetime decay test on the 1, 4-dimorpholinobenzene prepared in this example is shown in FIG. 4. It can be seen from fig. 4 that the phosphorescence emission peak is the lifetime in the order of milliseconds, which demonstrates that the emission at this wavelength is phosphorescence emission. The phosphorescent emission lifetime was calculated to be 589.107 ms using multiple exponential fits according to fig. 4.

Example 3

Adding 1,3, 5-tribromobenzene (6.4g, 20mmol), morpholine (7g, 80mmol), sodium tert-butoxide (7.5g, 78mmol), tris (dibenzylideneacetone) dipalladium (0.18g, 0.20mmol), (+ -) -2,2 '-bis- (diphenylphosphino) -1,1' -binaphthyl (0.38g, 0.61mmol) into 70mL of toluene solvent at the same time, stirring at 100 ℃ for 24h, extracting with water and dichloromethane (the volume ratio of the two is 1:3) after the reaction is finished, evaporating the solvent under reduced pressure, and purifying the product by chromatography, wherein the chromatography liquid adopts petroleum ether/ethyl acetate 1: 5. Recrystallization from absolute ethanol and vacuum drying gave 4.6g of a white powder, i.e., 1,3, 5-trimodarQuinoline benzene, yield 70%.¹HNMR(500MHz,CD₂Cl₂)δ6.06(s,1H),3.84(s,4H),3.13(s,4H)。

Fluorescence tests were performed on the 1,3, 5-trimorpholinobenzene prepared in this example, and the fluorescence emission spectrum at room temperature, the phosphorescence emission spectrum after 1 millisecond delay, and the lifetime decay curve obtained are shown in fig. 5. As can be seen from FIG. 5, the 1,3, 5-trimorpholinobenzene prepared in this example still has an emission peak after a delay of 1ms, which indicates that the material has phosphorescent emission at room temperature.

The lifetime decay curve obtained by performing the lifetime decay test on the 1,3, 5-trimorpholinobenzene prepared in this example is shown in FIG. 6. It can be seen from fig. 6 that the phosphorescence emission peak is the lifetime in the order of milliseconds, which demonstrates that the emission at this wavelength is phosphorescence emission. The phosphorescent emission lifetime was calculated to be 1037.81 ms using multiple exponential fits according to fig. 6.

Example 4

Adding 1,2,4, 5-tetrabromobenzene (5g, 13mmol), morpholine (5.3g, 61mmol), sodium tert-butoxide (6.7g,70mmol), tris (dibenzylideneacetone) dipalladium (0.22g, 0.24mmol) and (+/-) -2,2 '-bis (diphenylphosphino) -1,1' -binaphthyl (0.71g, 1.14mmol) into a toluene (70mL) solvent at the same time, stirring for 24h at 100 ℃, extracting with water and dichloromethane (the volume ratio of the two is 1:3) after the reaction is finished, evaporating the solvent under reduced pressure, and purifying the product by chromatographic column chromatography, wherein the chromatographic solution is petroleum ether/ethyl acetate 1: 2. Recrystallization from absolute ethanol and vacuum drying gave 1g of white powder, i.e. 1,2,4, 5-tetramorpholinobenzene, in 20% yield.¹HNMR(500MHz,CD₂Cl₂)δ6.56(s,1H),3.83(s,8H),3.15(s,8H)。

Fluorescence tests of 1,2,4, 5-tetramorpholinobenzene prepared in this example gave a fluorescence emission spectrum at room temperature, a phosphorescence emission spectrum delayed by 1ms, and a lifetime decay curve as shown in FIG. 7. As can be seen from FIG. 7, the 1,2,4, 5-tetramorpholinobenzene prepared in this example still has an emission peak after a delay of 1ms, which indicates that the material has phosphorescent emission at room temperature.

The lifetime decay curve obtained by performing the lifetime decay test on the 1,2,4, 5-tetramorpholinobenzene prepared in this example is shown in FIG. 8. It can be seen from fig. 8 that the phosphorescence emission peak is the lifetime in the order of milliseconds, which demonstrates that the emission at this wavelength is phosphorescence emission. The phosphorescent emission lifetime was calculated to be 242.89 ms using multiple exponential fits according to fig. 8.

It can be seen from this example that although the yield of 1,2,4, 5-tetramorpholinobenzene prepared in this example is low, it still has a long phosphorescence emission lifetime, because the substitution sites are too many, resulting in too many byproducts and thus low yield, but it does not affect the phosphorescence emission lifetime of the material.

Example 5

1, 4-dibromobenzene (1.2g, 10mmol) and morpholine (0.5g, 12mmol), sodium tert-butoxide (0.96g, 10mmol), tris (dibenzylideneacetone) dipalladium (0.03g, 0.033mmol) and tris (o-methylphenyl) phosphorus (0.03g, 0.099mmol) are added into 30mL of toluene at the same time, the mixture is stirred at 100 ℃ for 24h, after the reaction is finished, the mixture is extracted by water and dichloromethane (the volume ratio of the two is 1:3), the product is purified by chromatographic column chromatography after the solvent is evaporated under reduced pressure, and the chromatographic solution is petroleum ether/ethyl acetate 1: 9. Recrystallization from absolute ethanol and vacuum drying gave 1.93g of white powder, i.e. 4- (4-bromobenzene) morpholine, in 80% yield.¹HNMR(500MHz,CD₂Cl₂)δ7.43–7.35(m,1H),6.84(d,J＝6.4Hz,1H),3.85(s,2H),3.14(d,J＝2.9Hz,2H)。

Fluorescence measurements of 4- (4-bromobenzene) morpholine prepared in this example are shown in FIG. 9, which shows fluorescence emission spectra at room temperature, phosphorescence emission spectra after 1ms delay, and lifetime decay curves. As can be seen from FIG. 9, the 4- (4-bromobenzene) morpholine prepared in this example still has an emission peak after 1ms delay, which indicates that the material has phosphorescent emission at room temperature.

The lifetime decay curve obtained by performing the lifetime decay test on 4- (4-bromobenzene) morpholine prepared in this example is shown in FIG. 10. It can be seen from fig. 10 that the phosphorescence emission peak is the lifetime in the order of milliseconds, which demonstrates that the emission at this wavelength is phosphorescence emission. The phosphorescent emission lifetime was calculated to be 8.006 ms using multiple exponential fits according to fig. 10.

Example 6

Adding 4,4' -dibromodiphenyl sulfide (3.43g, 10mmol), morpholine (2g, 24mmol), sodium tert-butoxide (1.25g,13mmol), tris (dibenzylideneacetone) dipalladium (0.0915g, 0.1mmol), (+ -) -2,2' -bis (diphenylphosphino) -1,1' -binaphthyl (0.124g, 0.19mmol) into a toluene (70mL) solvent at the same time, stirring at 100 ℃ for 24h, extracting with water and dichloromethane (the volume ratio of the two is 1:3) after the reaction is finished, evaporating the solvent under reduced pressure, and purifying the product by chromatographic column chromatography, wherein the chromatographic solution is petroleum ether/ethyl acetate 1: 3. Recrystallization from anhydrous ethanol and vacuum drying gave 2.1g of white powder, i.e. bis (4-phenylmorpholine) sulfide, in 61% yield.¹H NMR(500MHz,CD₂Cl₂)δ7.28(d,1H),6.87(d,1H),3.88-3.80(m,2H),3.20-3.11(m,2H)。

Fluorescence measurements of bis (4-phenylmorpholine) sulfide prepared in this example gave a fluorescence emission spectrum at room temperature, a phosphorescence emission spectrum delayed by 1 millisecond, and a lifetime decay curve as shown in FIG. 11. As can be seen from FIG. 11, the bis (4-phenylmorpholine) sulfide prepared in this example still has an emission peak after a delay of 1ms, which indicates that the material has phosphorescent emission at room temperature.

The lifetime decay curve obtained by performing the lifetime decay test on the bis (4-phenylmorpholine) sulfide prepared in this example is shown in FIG. 12. It can be seen from fig. 12 that the phosphorescence emission peak is the lifetime in the order of milliseconds, which demonstrates that the emission at this wavelength is phosphorescence emission. The phosphorescent emission lifetime can be calculated to be 12.42 ms using multiple exponential fits.

Example 7

Adding 4,4' -dibromodiphenyl ether (3.28g, 10mmol), morpholine (2g, 24mmol), sodium tert-butoxide (1.25g,13mmol), tris (dibenzylideneacetone) dipalladium (0.0915g, 0.1mmol) and (+ -) -2,2' -bis (diphenylphosphino) -1,1' -binaphthyl (0.124g, 0.19mmol) into a toluene (70mL) solvent at the same time, stirring at 100 ℃ for 24h, extracting with water and dichloromethane (the volume ratio of the two is 1:3) after the reaction is finished, evaporating the solvent under reduced pressure, and purifying the product by chromatography, wherein the chromatography liquid is petroleum ether/ethyl acetate 1: 3. Recrystallization from absolute ethanol and vacuum drying gave 2.23g of a white powder, i.e., bis (4-phenylmorpholine) ether, in 68% yield. 1H NMR (500MHz, CD2Cl2) delta 7.01-6.84 (m,1H), 3.95-3.78 (m,1H), 3.18-3.00 (m, 1H).

The fluorescence test of bis (4-phenylmorpholine) ether prepared in this example gave a fluorescence emission spectrum at room temperature, a phosphorescence emission spectrum delayed by 1 millisecond, and a lifetime decay curve as shown in FIG. 13. As can be seen from FIG. 13, the bis (4-phenylmorpholine) ether prepared in this example still has an emission peak after a delay of 1ms, which indicates that the material has phosphorescent emission at room temperature.

The lifetime decay curve obtained by performing the lifetime decay test on the bis (4-phenylmorpholine) ether prepared in this example is shown in FIG. 14. It can be seen from fig. 14 that the phosphorescence emission peak is the lifetime in the order of milliseconds, which demonstrates that the emission at this wavelength is phosphorescence emission. Phosphorescence emission lifetime of 4.84 milliseconds was calculated using multiple exponential fits.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.