Photoinduced Chiral Radical Molecules Based on Triarylamine Derivatives with Circularly Polarized Luminescence Properties

Abstract

The present invention discloses a photo-generated chiral radical molecule based on a triarylamine derivative with circularly polarized luminescence properties, and its preparation and application. It is prepared by subjecting tris(4-aminophenyl)amine to an amide condensation reaction with an aryl-containing chiral isocyanate or an aryl-containing chiral carboxylic acid. The triarylamine derivative molecule of the present invention has the characteristics of being easy to generate and detect chiral radicals. In addition to being detected by ultraviolet-visible absorption spectroscopy and CD spectroscopy, the generation of radicals can also be judged by color change. The planarization of the conformation of the triarylamine molecule itself after the generation of radicals makes it easy to undergo self-aggregation, thereby amplifying the chiral signal. The positive charge carried can also interact with other negatively charged molecules through charge interaction to generate chiral transfer or induce self-assembly. The amide bond and urea bond components contained in the molecule enable the regulation of hydrogen bond interaction and hydrophilic-hydrophobic effect by solvents to change the circularly polarized luminescence intensity and direction brought by its aromatic group part.

Description

Technical Field

[0001] The present invention belongs to the field of circularly polarized luminescence, and particularly relates to a photo-generated chiral radical molecule based on a triarylamine derivative with circularly polarized luminescence properties, and its preparation and application. Background Art

[0002] Triarylamine molecules and their derivatives and triarylamine-based covalent polymers have been widely studied in academia and industry due to their interesting electronic and optical properties, and are used in optoelectronic applications such as designing discrete mixed-valence model compounds and electrochromic materials. In triarylamine molecules, due to the lone pair electrons on the nitrogen atom undergoing p-π conjugation with the three connected benzene rings, triarylamine has a very low ionization potential and is very easy to form cation radicals under the conditions of oxidants, light, and electrolysis. As a unique organic radical species, it has successfully shown great application potential in a wide range of fields including organic redox catalysis, organic semiconductors, and magnetic materials, mainly because of its excellent redox activity. Such as magic blue, which is usually used as a p-type redox dopant in semiconductor polymers.

[0003] Circularly polarized luminescence (CPL) is a phenomenon in which the left and right circularly polarized lights emitted by a luminescent substance are different. With its unique optical properties, it has important application values in fields such as biosensors, 3D displays, information encryption storage, and asymmetric catalytic synthesis, and has become a research hotspot in recent years. At the same time, circularly polarized light reflects the chiral information of the excited state of molecules, which involves the dipole arrangement of excited state molecules and has a unique role in exploring the configuration and conformation of excited state molecules as well as the molecular packing arrangement. Summary of the Invention

[0004] The object of the present invention is to provide a compound represented by the following formula I, formula II or formula III:

[0005]

[0006]

[0007] The compounds represented by the above formula I, formula II and formula III are prepared by a method comprising the following steps:

[0008] Subjecting tris(4-aminophenyl)amine to an amide condensation reaction with an aryl-containing chiral isocyanate to obtain the product;

[0009] Or

[0010] First reacting an aryl-containing chiral carboxylic acid to form an acyl chloride, and then subjecting it to an amide condensation reaction with tris(4-aminophenyl)amine to obtain the product,

[0011] In the above method, the molar ratio of tris(4-aminophenyl)amine to the aryl-containing chiral isocyanate or acyl chloride can be 1:3 - 5, specifically 1:3.3;

[0012] The amide condensation reaction is carried out in an organic solvent, and the organic solvent can specifically be dichloromethane;

[0013] The temperature of the amide condensation reaction can be room temperature, and the time can be 2 - 6 days, specifically 3 days or 5 days.

[0014] Specifically, tris(4-aminophenyl)amine undergoes an amide condensation reaction with (1-naphthyl)ethyl isocyanate to obtain the compound shown in Formula I;

[0015] Tris(4-aminophenyl)amine undergoes an amide condensation reaction with (1-phenyl)ethyl isocyanate to obtain the compound shown in Formula II;

[0016] 2-Phenylpropionic acid is reacted to form an acyl chloride, and then undergoes an amide condensation reaction with tris(4-aminophenyl)amine to obtain the compound shown in Formula III.

[0017] The application of the compound shown in Formula I, Formula II or Formula III in the preparation of photo-generated chiral radicals also belongs to the protection scope of the present invention.

[0018] The present invention also provides a method for preparing photo-generated chiral radicals.

[0019] The method for preparing photo-generated chiral radicals provided by the present invention includes the following steps:

[0020] 1) Dissolve the compound shown in Formula I, Formula II or Formula III in N,N-dimethylformamide, add a chlorine-containing solvent, mix well, seal, and let stand;

[0021] 2) Place it under an ultraviolet light source for irradiation to obtain photo-generated chiral radicals.

[0022] In the above method step 1), the standard for mixing evenly is that the solution is clear and transparent without precipitation.

[0023] The chlorine-containing solvent can be dichloromethane (DCM) or chloroform;

[0024] The concentration of the compound shown in Formula I, Formula II or Formula III in N,N-dimethylformamide is less than 5 mg / mL, or in the range of 10 -3 ~10 -5 mol / L;

[0025] The volume of the chlorine-containing solvent is 1 - 3 times the volume of N,N-dimethylformamide;

[0026] The solubility of the sample in DMF at room temperature is not higher than 5 mg / mL, 10-3 ~10 -5 Samples within the range of ~10 mol / L can all achieve ideal experimental results. For the amount of the chlorine-containing solvent such as DCM used, the volume should be between 1 to 3 times the volume of DMF used. If the amount of DCM used is too small, the concentration of free radicals generated will decrease or even it is difficult to generate free radicals. If too much, the triarylamine molecules will precipitate out, destroying the uniformity of the system;

[0027] In step 2) of the above method, the irradiation time can be 3 - 30 min; the ultraviolet light illumination power density is 0.3 mW / cm 2 ~3.4 mW / cm 2 ;

[0028] Whether free radicals are generated is judged by ultraviolet - visible absorption spectrum test, electron paramagnetic resonance (EPR) test, and the color change of the sample: the absorption spectrum signal peak of the sample will undergo a certain degree of blue shift, and new signal peaks representing free radicals will appear in the 400 - 500 nm region. EPR generates a typical N + cation radical triplet signal, and the color of the sample will also change significantly. In addition, circular dichroism spectrum (CD) test shows that the supramolecular free radicals generated by illumination have chiral characteristics.

[0029] The application of the compound shown in the above formula I, formula II or formula III in the preparation of materials with circularly polarized luminescence properties also belongs to the protection scope of the present invention.

[0030] The present invention also provides a method for obtaining a circularly polarized luminescence system by using the compound shown in formula I, formula II or formula III.

[0031] The method for obtaining a circularly polarized luminescence system provided by the present invention includes the following steps:

[0032] 1) Dissolve the compound shown in formula I, formula II or formula III in N,N - dimethylformamide,

[0033] 2) Add a poor solvent to the obtained solution and mix evenly to obtain.

[0034] In step 1) of the above method, the concentration of the compound shown in formula I, formula II or formula III in N,N - dimethylformamide is lower than 5 mg / mL, or within the range of 10 -3 ~10 -5 mol / L;

[0035] In step 2), the poor solvent can specifically be H2O, and the molar ratio of DMF:H2O can be 10:0 to 1:9;

[0036] The poor solvent can also be DCM, and the molar ratio of DMF:DCM can be 4:6 to 1:9.

[0037] A series of triarylamine derivative molecules designed by the present invention have the characteristics of being easy to generate and detect chiral free radicals. In addition to being detected by ultraviolet-visible absorption spectroscopy and CD spectroscopy, the generation of free radicals can also be judged by macroscopic color changes. The planarization of the conformation of the triarylamine molecule itself after generating free radicals makes it easy to undergo self-aggregation, thereby amplifying the chiral signal. The positive charge carried can also interact with other negatively charged molecules through charge interaction to generate chiral transfer or induce self-assembly. The amide bond and urea bond components contained in the molecule enable the regulation of hydrogen bond interaction and hydrophilic-hydrophobic effect by solvents to change the circularly polarized luminescence intensity and direction brought by its aromatic group part. Description of the Drawings

[0038] Figure 1 1H NMR spectra of the triarylamine derivative molecules represented by Formula I, Formula II and Formula III in the present invention.

[0039] Figure 2 Ultraviolet-visible absorption spectra and circular dichroism spectra of the samples of the triarylamine derivative molecules represented by Formula I, Formula II and Formula III in the present invention varying with the ultraviolet irradiation time.

[0040] Figure 3 Photos of the samples of the triarylamine derivative molecules represented by Formula I, Formula II and Formula III in the present invention before and after ultraviolet irradiation.

[0041] Figure 4 Electron paramagnetic resonance spectrum of the triarylamine derivative molecule S-UN represented by Formula I in the present invention varying with the ultraviolet light irradiation time.

[0042] Figure 5 Fluorescence spectrum of the triarylamine derivative molecule S-UN represented by Formula I in the present invention.

[0043] Figure 6 Circularly polarized luminescence spectrum of the triarylamine derivative molecule S-UN represented by Formula I in the present invention. Detailed Embodiments

[0044] The present invention will be further described in detail below in conjunction with the specific embodiments. The examples given are only for clarifying the present invention, rather than limiting the scope of the present invention. The following examples can be used as a guide for those of ordinary skill in the art to make further improvements, and do not constitute any limitation to the present invention in any way.

[0045] The experimental methods in the following examples are all conventional methods unless otherwise specified, and are carried out according to the techniques or conditions described in the literature in this field or according to the product specifications. The materials, reagents, etc. used in the following examples can be obtained from commercial channels unless otherwise specified.

[0046] Example 1: Preparation of triarylamine derivative (S / R-UN) and its photo-generated radical sample

[0047] The synthetic route is as follows:

[0048]

[0049] Dissolve tris(4-aminophenyl)amine (580 mg, 2 mmol, purchased from Ark Co., Ltd.) in ultra-dry dichloromethane (150 mL, purchased from InnoChem Co., Ltd.), place it in an ultrasonic environment to promote complete dissolution, and then add (S)-(+)-1-(1-naphthyl)ethyl isocyanate / (R)-(-)-1-(1-naphthyl)ethyl isocyanate (1305.5 mg, 6.6 mmol, purchased from Tci Co., Ltd.). React at room temperature for 72 hours in the dark. After the reaction, a solid precipitates. Stop the reaction and filter the reaction solution. Dissolve the obtained precipitate in DMF (20 mL, purchased from Concord Technology (Tianjin) Co., Ltd.) and drop it into DCM (200 mL, Concord Technology (Tianjin) Co., Ltd.) for recrystallization. Filter the insoluble matter again and dry it under vacuum to obtain the product S / R-UN. The product yield is 47.3%.

[0050] The structure verification data of the target product are as follows:

[0051] S-UN: 1 H NMR (400 MHz, DMSO) δ8.26 (s, 1H), 8.15 (d, J = 8.4 Hz, 1H), 7.94 (d, J

[0052] = 8.0 Hz, 1H), 7.83 (d, J = 8.0 Hz, 1H), 7.61–7.46 (m, 4H), 7.23 (d, J = 8.7 Hz, 2H), 8.35–1.31 (m, 8H), 6.78 (d, J = 8.7 Hz, 2H), 6.65 (d, J = 7.8 Hz, 1H), 5.68–5.50 (m, 1H), 1.52 (d, J = 6.7 Hz, 3H);

[0053] R-UN: 1 H NMR (400 MHz, DMSO) δ8.25 (s, 1H), 8.16 (d, J = 8.4 Hz, 1H), 7.94 (d, J

[0054] =7.8Hz, 1H), 7.83 (d, J=7.9Hz, 1H), 7.62–7.46 (m, 4H), 7.23 (d, J=8.8Hz, 2H), 6.78 (d, J=8.8Hz, 2H), 6.64 (d, J=7.8Hz, 1H), 5.68–5.55 (m, 1H), 1.53 (d, J=6.8Hz, 3H). See Figure 1 。

[0055] MS (MALDI-TOF): m / z (%) : 881.41 [M]+

[0056] The preparation of the photo-generated radical sample is as follows, taking S-UN as an example:

[0057] Step 1) Take 8.8 mg of the S-UN sample and dissolve it in 20 mL of DMF. The concentration of this preparation solution is 0.5 mmol / L;

[0058] Step 2) Take 200 μL of the solution obtained in Step 1), add 600 μL of DMF and mix well, then add 2 mL of DCM. After mixing well, transfer it to a screw-cap quartz cuvette (1 cm × 1 cm × 3.5 cm), seal it and let it stand. The sample is a colorless, clear and transparent solution.

[0059] Step 3) Place the sample prepared in Step 2) under a 365 nm ultraviolet light source and irradiate it for 15 minutes. It can be observed that the sample turns into a dark green clear solution ( Figure 3 ), and perform ultraviolet-visible absorption spectroscopy and circular dichroism spectroscopy tests on it. The results are as Figure 2 shown. The absorption signal peak at 320 nm in the absorption spectrum shows a blue shift, and new signal peaks appear at 400 - 450 nm and 600 nm. The signal at 300 nm in the CD spectrum is enhanced and shows a blue shift. Figure 4 is the electron paramagnetic resonance (EPR) spectrum of the sample prepared in Step 2 of S-UN as a function of ultraviolet light irradiation time. The obtained spectrum is a typical triplet spectrum representing N + cation radical. The results of the absorption spectroscopy and EPR experiments both prove the generation of photo-generated radicals.

[0060] Example 2. Preparation of triarylamine derivative (S / R-UP) and its photo-generated radical sample

[0061]

[0062] Dissolve tris(4-aminophenyl)amine (580 mg, 2 mmol, purchased from Ark Co., Ltd.) in ultradry dichloromethane (150 mL), place it in an ultrasonic environment to promote complete dissolution, and then add (S)-(+)-1-(1-phenylethyl) isocyanate / (R)-(-)-1-(1-phenylethyl) isocyanate (971.4 mg, 6.6 mmol, purchased from Tci Co., Ltd.). React at room temperature for 72 hours in a light-shielded environment. After the reaction, a solid precipitates. Stop the reaction and filter the reaction solution. Retain the precipitate and dissolve it in DMF (20 mL, purchased from Concord Technology (Tianjin) Co., Ltd.). Drop it into DCM (200 mL, purchased from Concord Technology (Tianjin) Co., Ltd.) for recrystallization. Filter the insoluble matter again and dry it under vacuum to obtain the product S / R-UP. The product yield is 54.6%.

[0063] The structure verification data of the target product are as follows:

[0064] S-UP: 1 H NMR (400 MHz, DMSO) δ8.25 (s, 1H), 7.34 (d, J = 4.3 Hz, 5H), 7.23 (d, J

[0065] = 8.9 Hz, 3H), 6.79 (d, J = 8.8 Hz, 2H), 6.51 (d, J = 7.9 Hz, 1H), 4.87–4.72 (m, 1H), 1.38 (d, J = 6.9 Hz, 3H);

[0066] R-UP: 1 H NMR (400 MHz, DMSO) δ8.25 (s, 1H), 7.34 (d, J = 4.3 Hz, 4H), 7.23 (d, J

[0067] = 8.8 Hz, 3H), 6.79 (d, J = 8.8 Hz, 2H), 6.51 (d, J = 7.9 Hz, 1H), 4.85–4.76 (m, 1H), 1.38 (d, J = 6.9 Hz, 3H).

[0068] See Figure 1 .

[0069] MS (MALDI-TOF): m / z (%) : 731.21 [M]+

[0070] The preparation of the photo-generated radical sample is as follows, taking S-UP as an example:

[0071] Step 1) Take 7.3 mg of the S-UP sample and dissolve it in 20 mL of DMF. The concentration of this prepared solution is 0.5 mmol / L;

[0072] Step 2) Take 200 μL of the solution obtained in Step 1, add 600 μL of DMF and mix well, then add 2 mL of DCM, mix well and transfer to a screw-cap quartz cuvette (1 cm × 1 cm × 3.5 cm), seal and let stand. The sample is a colorless, clear and transparent solution.

[0073] Step 3) Place the sample prepared in Step 2 under a 365 nm ultraviolet light source and irradiate for 15 minutes. It can be observed that the sample turns into a tea-brown clear solution ( Figure 3 ), and perform ultraviolet-visible absorption spectroscopy and circular dichroism spectroscopy tests on it. The results are as Figure 2 shown. The absorption signal peak at 320 nm in the absorption spectrum undergoes a blue shift, and new signal peaks appear at 400 - 450 nm and 600 nm. The signal at 300 nm in the CD spectrum is enhanced.

[0074] Example 3. Preparation of triarylamine derivative (S / R-AN) and its photo-generated radical sample

[0075] The synthesis route is as follows:

[0076]

[0077] The specific operation is as follows:

[0078] Step 1) Dissolve S / R-2-phenylpropionic acid (1350.6 mg, 9 mmol, purchased from Aladdin Chemistry) in ultradry dichloromethane (60 mL, purchased from Innochem) and add oxalyl chloride (4661.6 mg, 36 mmol, purchased from Innochem). Stir the mixed solution at room temperature for 24 hours. Use a rotary evaporator not higher than 40 °C to remove the solvent components, and use a small amount of ultradry dichloromethane (5 mL) to dissolve the solid part for use in the next step.

[0079] Step 2) Dissolve tris(4-aminophenyl)amine (580 mg, 2 mmol, purchased from Ark) and triethylamine (5 mL) together in ultradry dichloromethane (150 mL, purchased from Innochem), and place it in an ice-water bath. Slowly dropwise add the mixture from Step 1), and then stir in the dark at room temperature for 5 days. The dropping process should be completed within half an hour after preparing the mixture in Step 1). Extract by adding water (from Mini Q water purifier, 18.2 MΩ·cm) to the reaction solution, filter the aqueous phase and dry to obtain the product S / R-AN. The product yield is 84.7%.

[0080] The structure verification data of the target product are as follows:

[0081] S-AN: 11H NMR (400 MHz, DMSO, 25 °C, TMS) δ 9.97 (s, 1H), 7.45 (d, J = 8.8 Hz,

[0082] 2H), 7.37 (d, J = 7.2 Hz, 2H), 7.31 (t, J = 7.5 Hz, 2H), 7.23 (t, J = 7.2 Hz, 1H), 6.84 (d, J = 8.8 Hz, 2H), 3.78 (q, J = 6.7 Hz, 1H), 1.39 (d, J = 6.9 Hz, 3H);

[0083] R-AN: 1 1H NMR (400 MHz, DMSO, 25 °C, TMS) δ 9.97 (s, 1H), 7.45 (d, J = 8.8 Hz,

[0084] 2H), 7.37 (d, J = 7.2 Hz, 2H), 7.31 (t, J = 7.5 Hz, 2H), 7.23 (t, J = 7.2 Hz, 1H), 6.84 (d, J = 8.8 Hz, 2H), 3.78 (q, J = 6.7 Hz, 1H), 1.39 (d, J = 6.9 Hz, 3H).

[0085] See Figure 1 。

[0086] MS (MALDI-TOF): m / z (%) : 686.33 [M]+.

[0087] The preparation of the photo-generated free radical sample is as follows, taking S-AN as an example:

[0088] Step 1) Take 6.8 mg of S-AN sample and dissolve it in 20 mL of DMF. The concentration of this preparation solution is 0.5 mmol / L;

[0089] Step 2) Take 200 μL of the solution obtained in Step 1, add 600 μL of DMF and mix well, then add 2 mL of DCM, mix well and transfer it to a screw-cap quartz cuvette (1 cm × 1 cm × 3.5 cm), seal and let stand. The sample is a colorless, clear and transparent solution.

[0090] Step 3) Place the sample prepared in Step 2 under a 365 nm ultraviolet light source and irradiate it for 15 minutes. It can be observed that the sample turns into a light pink clear solution ( Figure 3 ), and perform ultraviolet-visible absorption spectroscopy and circular dichroism spectroscopy tests on it. The results are as Figure 2 shown. The absorption signal peak at 320 nm in the absorption spectrum shows a blue shift, and new signal peaks appear at 400 - 450 nm. The signal at 300 nm in the CD spectrum is enhanced and shows a blue shift.

[0091] Example 4: Circularly Polarized Luminescence Test of Triarylamine Derivative (S-UN)

[0092] The specific operations are as follows:

[0093] Step 1) Take 30 mg of the S-UN sample and dissolve it in 6 mL of DMF. Heat and ultrasonicate to completely dissolve it;

[0094] Step 2) Take 200 μL of the solution obtained in Step 1), add 1200 μL of DMF and mix well. Then add 600 μL of H2O, mix well and transfer it to a screw-cap quartz cuvette (1 cm × 1 cm × 3.5 cm). Seal and let it stand. The concentration of S-UN in the sample is 0.5 mg / mL, and the solvent volume ratio is DMF:H2O = 10:0 - 1:9. Set the excitation wavelength to 300 nm and perform circularly polarized luminescence spectroscopy test.

[0095] Figure 5 It is the fluorescence spectrum of S-UN.

[0096] Figure 6 It is the circularly polarized luminescence spectrum of S-UN.

[0097] The present invention has been described in detail above. For those skilled in the art, without departing from the purpose and scope of the present invention and without unnecessary experiments, the present invention can be implemented within a relatively wide range under equivalent parameters, concentrations and conditions. Although specific examples of the present invention are given, it should be understood that the present invention can be further improved. In short, according to the principle of the present invention, this application intends to include any changes, uses or improvements to the present invention, including changes made by using conventional techniques known in the art that are outside the scope disclosed in this application.

Claims

1. Compounds represented by Formula I, Formula II or Formula III:

2. A method for preparing the compound represented by Formula I, Formula II or Formula III in claim 1, comprising the following steps: Subjecting tris(4-aminophenyl)amine to an amide condensation reaction with an aryl-containing chiral isocyanate to obtain the compound; Or First reacting the aryl-containing chiral carboxylic acid to form an acyl chloride, and then subjecting it to an amide condensation reaction with tris(4-aminophenyl)amine to obtain the compound; the aryl-containing chiral isocyanate is (1-naphthyl)ethyl isocyanate or (1-phenyl)ethyl isocyanate; The aryl-containing chiral carboxylic acid is 2-phenylpropanoic acid; The amide condensation reaction is carried out in an organic solvent, and the organic solvent is dichloromethane; The temperature of the amide condensation reaction is room temperature and the time is 2 - 6 days.

3. The method according to claim 2, wherein: The molar ratio of tris(4-aminophenyl)amine to the aryl-containing chiral isocyanate or acyl chloride is 1:3 - 5.

4. Use of the compound represented by Formula I, Formula II or Formula III in claim 1 in the preparation of photoinduced chiral radicals.

5. A method for preparing photoinduced chiral radicals, comprising the following steps: 1) Dissolving the compound represented by Formula I, Formula II or Formula III in claim 1 into N,N-dimethylformamide, adding a chlorinated solvent, mixing evenly, sealing, and standing still; 2) Irradiating under an ultraviolet light source to obtain photoinduced chiral radicals; The chlorinated solvent is dichloromethane or chloroform; In step 1), the concentration of the compound represented by formula I, formula II or formula III in N,N-dimethylformamide is less than 5 mg / mL, or within the range of 10 -3 -10 -5 mol / L; The volume of the chlorinated solvent is 1 - 3 times the volume of N,N-dimethylformamide; In step 2), the irradiation time is 3 - 30 min.

6. Use of the compound represented by Formula I, Formula II or Formula III in claim 1 in the preparation of materials with circularly polarized luminescence properties.

7. A method for obtaining a circularly polarized luminescence system, comprising the following steps: 1) Dissolving the compound represented by Formula I, Formula II or Formula III in claim 1 into N,N-dimethylformamide, 2) Adding a poor solvent to the obtained solution and mixing evenly to obtain the circularly polarized luminescence system; In Step 1), the concentration of the compound represented by Formula I, Formula II or Formula III in N,N-dimethylformamide is less than 5 mg / mL or within the range of 10 -3 - 10 -5 mol / L; In step 2), the poor solvent is H2O, wherein, The molar ratio of N,N-dimethylformamide:H2O is 10:0 - 1:9.

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