An allyl luminescent radical material and a method for preparing the same

Abstract

The application provides an allyl luminescent free radical material and a preparation method thereof, and belongs to the technical field of luminescent materials. The allyl luminescent free radical material provided by the application has a structure shown in formula I: formula I. The application constructs an asymmetric triarylmethyl free radical derivative by introducing a five-membered aromatic ring, uses a steric hindrance effect to inhibit spin delocalization, promotes spin electrons to be localized in an allyl core, thereby constructing an intrinsic luminescent allyl free radical core structure unit, further accurately introduces an electron donor functional unit outside the free radical core, systematically controls the electronic structure and the front molecular orbital energy level of the D-A type free radical, and finally realizes a novel free radical luminescent system with high fluorescence quantum yield and a wide spectrum control range (700-1100 nm).

Description

Technical Field

[0001] This invention relates to the field of luminescent materials technology, and in particular to an allyl luminescent free radical material and its preparation method. Background Technology

[0002] Organic radical luminescent materials, with their unique open-shell electronic structure and photophysical properties, have shown promising applications in high-efficiency organic light-emitting diodes (OLEDs), electrochromic devices, molecular-level quantum information technology carriers, and precise photodynamic therapy probes. However, the structural diversity of organic luminescent single-radical systems remains insufficient, with reported systems mainly focusing on the following categories: TTM / PTM type radicals, anthracene derivatives, and biscarbazole-substituted triarylmethyl derivatives. Developing and preparing novel single-radical luminescent cores remains a pressing issue in this field.

[0003] Among the reported organic light-emitting single-radical materials, TTM and PTM-type radicals have been successfully used in the fabrication and application of OLED devices due to their significant photophysical performance advantages—especially their high fluorescence quantum yield. For example, in 2018, Li Feng's team, in collaboration with RHFriend's research group, experimentally demonstrated that single-radical materials can achieve an internal quantum efficiency (IQE) close to 100%. By changing the carbazole bonding mode of TTM derivatives, the EQE of their OLEDs can reach 27% and 17%, respectively. T. Kusamoto's team developed a series of pyridine-containing methyl radicals, PyBTM, bis-PyTM, and trisPyM. Compared to TTM radicals, the introduction of pyridine gives these compounds a lower energy level, thus exhibiting superior air stability. He Zikai's team reported a bis-carbazole-substituted triarylmethyl radical, which exhibited rare near-infrared emission (1020 nm), but its fluorescence yield was too low to be detected. Li Zhen's group, in collaboration with Wu Jishan's and Li Feng's teams, reported a series of stable xanthracene monoradicals. These radical compounds exhibit good photostability and near-infrared fluorescence. Their OLED devices can achieve an IQE of nearly 81%, further demonstrating the potential of radical materials in the OLED field. Therefore, how to prepare novel air-stable radical units through molecular design, and then construct radical luminescent materials with both high-efficiency luminescence and spectrally tunable properties, has become a key scientific problem urgently needing breakthroughs in this field.

[0004] Introducing donor-acceptor structures containing non-alternating aromatic compounds, regulating the symmetry of molecular orbitals, and non-bonded connections between donor-acceptor units are crucial for constructing radical luminescent systems that combine high quantum efficiency with excellent stability. Allyl radicals, as a class of open-shell π-system molecules with unique three centers and three electrons, have attracted much attention due to their excellent air stability. However, the delocalization of their unpaired electrons and low-energy excited states cause their energy to be released through non-radiative transitions, resulting in allyl radicals not emitting light. Summary of the Invention

[0005] In view of this, the purpose of this invention is to develop and prepare a new single radical luminescent core, and to provide an allyl luminescent radical material and its preparation method.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] One of the technical solutions of this invention is an allyl luminescent free radical material, having the structure shown in Formula I:

[0008]

[0009] Where · represents a single electron of a free radical;

[0010] R can be any of the following structures:

[0011]

[0012] X is

[0013] In a preferred embodiment of the present invention, the allyl luminescent radical material has the structure shown in formulas a to p:

[0014] The second technical solution of the present invention is a method for preparing the above-mentioned allyl luminescent free radical material, wherein X is... The preparation method of an allyl luminescent free radical material having the structure shown in Formula I includes the following steps:

[0015] Step 1. Compound 1 and compound 2 are subjected to Friedel-Crafts alkylation reaction 1 to obtain Friedel-Crafts alkylated product 1;

[0016] Step 2. The Friedel-Crafts alkylation product 1 is subjected to an oxidation reaction to obtain an oxidation product;

[0017] Step 3. The oxidation product is subjected to dehydrogenation reaction 1 to obtain the allyl luminescent free radical material;

[0018] When X is The preparation method of an allyl luminescent free radical material having the structure shown in Formula I includes the following steps:

[0019] Step S1. Compound 1 and compound 3 are subjected to Friedel-Crafts alkylation reaction 2 to obtain Friedel-Crafts alkylated product 2;

[0020] Step S2. The Friedel-Crafts alkylation product 2 is subjected to a dehydrogenation reaction 2 to obtain the allyl luminescent radical material;

[0021] The structural formula of compound 1 is as follows:

[0022] The structural formula of compound 2 is as follows:

[0023] The structural formula of compound 3 is as follows:

[0024] In compounds 2 and 3, R is the same as R in formula I above.

[0025] In a preferred embodiment of the present invention, in step 1, the catalyst used in the Friedel-Crafts alkylation reaction 1 is aluminum trichloride, and the solvent is anhydrous dichloromethane; the molar ratio of compound 1 to compound 2 is 1:(0.9-2); the molar ratio of compound 1 to aluminum trichloride is 1:1; the reaction temperature of the Friedel-Crafts alkylation reaction 1 is room temperature, and the reaction time is 1-3 hours.

[0026] The present invention does not impose any special limitation on the amount of anhydrous dichloromethane used in the above-mentioned Friedel-Crafts alkylation reaction 1. Conventional techniques used by those skilled in the art can be selected, such as adding 10 to 20 mL of solvent per 1 mmol of compound 1.

[0027] In this invention, after the Friedel-Crafts alkylation reaction 1 is completed, the reaction is further quenched with hydrochloric acid, and then the resulting reaction solution is extracted and purified.

[0028] In a preferred embodiment of the present invention, in step 2, the oxidant used in the oxidation reaction is peroxytrifluoroacetic acid or m-chloroperoxybenzoic acid, or other oxidants suitable for the oxidation reaction in the present invention may be selected. The solvent is anhydrous dichloromethane. The molar ratio of Friedel-Crafts alkylation product 1 to the oxidant peroxytrifluoroacetic acid is 1:(10-15); the molar ratio of Friedel-Crafts alkylation product 1 to the oxidant m-chloroperoxybenzoic acid is 1:(4-5); the oxidation reaction is carried out at room temperature for 12-14 hours.

[0029] The present invention does not impose any special limitation on the amount of anhydrous dichloromethane used in the above oxidation reaction. Conventional techniques skilled in the art can be used, such as adding 10 to 20 mL of solvent per 1 mmol of compound 1.

[0030] In this invention, after the oxidation reaction is completed, the reaction is further quenched with a saturated sodium bisulfite solution, and then the resulting reaction solution is extracted and purified.

[0031] In a preferred embodiment of the present invention, in step 3, the base in dehydrogenation reaction 1 is potassium tert-butoxide, the catalyst is 18-crown-6, the solvent is tetrahydrofuran, and the oxidant is tetrachlorobenzoquinone; the molar ratio of oxidation product, potassium tert-butoxide, 18-crown-6, and tetrachlorobenzoquinone is 1:8:8:8; the temperature of dehydrogenation reaction 1 is room temperature, the time is 12h, and the reaction is carried out in the dark.

[0032] The present invention does not impose any special limitation on the amount of tetrahydrofuran used in the above dehydrogenation reaction 1. Conventional techniques used by those skilled in the art can be used, such as adding 2 to 3 mL of solvent for every 1 μmol of compound 1.

[0033] In this invention, after the dehydrogenation reaction 1 is completed, the reaction is further quenched with saturated brine, and then the resulting reaction solution is extracted and purified.

[0034] In a preferred embodiment of the present invention, in step S1, the catalyst used in the Friedel-Crafts alkylation reaction 2 is aluminum trichloride, and the solvent is anhydrous dichloromethane; the molar ratio of compound 1 to compound 3 is 1:(0.09-0.12); the molar ratio of compound 1 to aluminum trichloride is 1:(0.1-0.2); the reaction temperature of the Friedel-Crafts alkylation reaction 2 is room temperature, and the reaction time is 1-3 h.

[0035] The present invention does not impose any special limitation on the amount of anhydrous dichloromethane used in the above-mentioned Friedel-Crafts alkylation reaction 2. Conventional techniques skilled in the art can be used, such as adding 10 to 20 mL of solvent per 1 mmol of compound 1.

[0036] In this invention, after the Friedel-Crafts alkylation reaction 2 is completed, the reaction is further quenched with hydrochloric acid, and then the resulting reaction solution is extracted and purified.

[0037] In a preferred embodiment of the present invention, in step S2, the base in dehydrogenation reaction 2 is potassium tert-butoxide, the catalyst is 18-crown-6, the solvent is tetrahydrofuran, and the oxidant is tetrachlorobenzoquinone; the molar ratio of Friedel-Crafts alkylation product 2 to potassium tert-butoxide, 18-crown-6, and tetrachlorobenzoquinone is 1:10:10:10; the temperature of dehydrogenation reaction 2 is room temperature, and the time is 12 hours.

[0038] The present invention does not impose any special limitation on the amount of base, catalyst and solvent used in the above dehydrogenation reaction 2. Conventional techniques used by those skilled in the art can be used, such as adding 2 to 3 mL of solvent for every 1 μmol of compound 1.

[0039] In this invention, after the dehydrogenation reaction 2 is completed, the reaction is further quenched with saturated brine, and then the resulting reaction solution is extracted and purified.

[0040] The present invention discloses the following technical effects:

[0041] This invention constructs an asymmetric triarylmethyl radical derivative by introducing a five-membered aromatic ring. By utilizing the steric hindrance effect to suppress spin delocalization, the spin electrons are localized to the allyl core, thereby constructing an intrinsically luminescent allyl radical core structural unit. Furthermore, by precisely introducing electron donor functional units around the radical core, the electronic structure and frontier molecular orbital energy levels of the DA-type radical are systematically regulated, ultimately achieving a novel radical luminescent system that combines high fluorescence quantum yield (11.7% for ARS-TPA(j)) and a wide spectral tuning range (700-1100 nm).

[0042] The allyl luminescent radical provided by this invention exhibits excellent electron transport capabilities, and its optical information shows that it emits wavelengths exceeding 700 nm in n-hexane solution. The allyl luminescent radical provided by this invention also possesses unique unpaired electrons.

[0043] This invention prepares a novel free radical unit with air stability—allyl luminescent free radical—through molecular design. Under natural light irradiation, the half-lives of ARS-Ph(a) and ARS-TPA(j) are 5.2 days and 27.5 days, respectively. A new single-radiative luminescent core was developed and prepared, constructing a free radical luminescent material with both high-efficiency luminescence and spectrally tunable characteristics, thus expanding the organic luminescent single-radiative system.

[0044] The method for preparing allyl luminescent free radical materials provided by this invention is simple, uses widely available raw materials, and yields high product purity. It shows excellent application prospects in high-efficiency organic light-emitting diodes (OLEDs), electrochromic devices, and photodynamic therapy probes. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 The UV absorption and fluorescence emission spectra of ARS-Ph(a), ARS-TPA(j), and ARC-Ph(l) prepared in Examples 1-3 are shown in solution.

[0047] Figure 2The EPR spectrum of ARS-Ph(a) prepared in Example 2 in toluene solution;

[0048] Figure 3 The EPR spectrum of ARS-TPA(j) prepared in Example 1 in toluene solution.

[0049] Figure 4 The photostability of ARS-Ph(a) prepared in Example 2 under natural light irradiation.

[0050] Figure 5 The photostability of ARS-TPA(j) prepared in Example 1 under natural light irradiation. Detailed Implementation

[0051] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0052] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0053] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0054] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0055] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0056] In this invention, unless otherwise specified, room temperature means 25±5℃.

[0057] This invention provides an allyl luminescent radical material having the structure shown in Formula I:

[0058]

[0059] Where · represents a single electron of a free radical;

[0060] R can be any of the following structures:

[0061]

[0062] X is

[0063] In this invention, when X is The preparation method of the allyl luminescent free radical material having the structure shown in Formula I includes the following steps:

[0064]

[0065] Under nitrogen protection, compound 1, aluminum trichloride, and anhydrous dichloromethane were added to a reaction flask and reacted at 0°C for 20 min. Then, compound 2 was added to the reaction flask and reacted at room temperature for 1–3 h. The reaction was quenched with hydrochloric acid, and the mixture was extracted multiple times with dichloromethane, dried, and purified by column chromatography (using petroleum ether:dichloromethane = 5:1 as eluent). The crude product was then washed with methanol to obtain compound 3.

[0066] Under nitrogen protection, oxidant, compound 3, and anhydrous dichloromethane were added to a reaction flask, and the mixture was reacted at room temperature for 12–14 h. The reaction was quenched with saturated sodium bisulfite solution, and the mixture was extracted multiple times with dichloromethane, dried, and purified by column chromatography (using petroleum ether:dichloromethane = 1:2 as eluent) to obtain compound 4.

[0067] The reaction was carried out in a glove box in the dark. Compound 4, potassium tert-butoxide, 18-crown-6, and anhydrous tetrahydrofuran were added to the reaction flask, and the reaction was carried out at room temperature for 5 h. Then tetrachlorobenzoquinone was added, and the reaction was continued at room temperature for 12 h. The reaction was quenched with saturated brine. The mixture was extracted multiple times with dichloromethane, dried, and purified by column chromatography to obtain the target product.

[0068] When X is The preparation method of the allyl luminescent free radical material having the structure shown in Formula I includes the following steps:

[0069]

[0070] Under nitrogen protection, compound 1, aluminum trichloride, and anhydrous dichloromethane were added to a reaction flask and reacted at 0°C for 20 min. Then, compound 10 was added to the reaction flask and reacted at room temperature for 2 h. The reaction was quenched with 0.1 M hydrochloric acid (10 mL). The mixture was extracted multiple times with dichloromethane, dried, and purified by column chromatography (using petroleum ether as eluent). The crude product was then washed with methanol to obtain compound 11.

[0071] The reaction was carried out in a glove box in the dark. Compound 11, potassium tert-butoxide, 18-crown-6, and anhydrous tetrahydrofuran were added to the reaction flask, and the reaction was carried out at room temperature for 5 h. Then, tetrachlorobenzoquinone was added, and the reaction was continued at room temperature for 12 h. The reaction was quenched with saturated brine, and the mixture was extracted multiple times with dichloromethane, dried, and purified by column chromatography (petroleum ether as eluent) to obtain compound 12, which was the target product.

[0072] Unless otherwise specified, the technical solutions described in this invention are all conventional solutions in the field, and the reagents or raw materials used are all purchased from commercial channels or are publicly available unless otherwise specified.

[0073] To better understand the present invention, the following embodiments further illustrate the content of the present invention, but the content of the present invention is not limited to the following embodiments.

[0074] Example 1

[0075] Synthesis of allyl luminescent radical ARS-TPA(j):

[0076]

[0077] Under nitrogen protection, compound 1 (3.18 mmol), aluminum trichloride (3.18 mmol), and anhydrous dichloromethane (50 mL) were added to a 250 mL reaction flask and reacted at 0 °C for 20 min. Then, compound 2 (3.02 mmol) was added to the reaction flask, and the reaction was carried out at room temperature for 3 h. The reaction was quenched with 0.1 M hydrochloric acid (50 mL), the mixture was extracted with dichloromethane, dried, and purified by column chromatography (petroleum ether:dichloromethane = 5:1 as eluent). The crude product was then washed with methanol to give compound 3 as a pale yellow solid (0.29 g, 14%). 1 H NMR (600MHz, CDCl3) δ (ppm): 7.96 (d, 1H), 7.91 (d, 1H), 7.42 (d, 2H), 7.41-7.38 (t, 2H), 7.34 (s, 1H), 7.12-7.09 (m, 6H), 7.07 (d, 4H), 2.33 (s, 6H); 13C NMR (150MHz, CDCl3) δ (ppm): 147.75,145.33,140.08,139.28,137.78,137.49,136.20,134 .32,133.74,132.59,130.01,129.34,127.87,124.42,123.10,122.33,46.01,20.98; HRMS analysis(APCI):calcd for C 41 H 26 Cl6NS(MH) - :773.9923,found:773.9924(error:0.13ppm).

[0078]

[0079] Under nitrogen protection, m-chloroperoxybenzoic acid (0.94 mmol), compound 3 (0.20 mmol), and anhydrous dichloromethane (5 mL) were added to a 50 mL reaction flask, and the reaction was carried out at room temperature for 14 h. The reaction was quenched with saturated sodium bisulfite solution, and the mixture was extracted multiple times with dichloromethane, dried, and purified by column chromatography (petroleum ether:dichloromethane = 1:2 as eluent) to give compound 4 as a yellow solid (52 mg, 32%). 1 H NMR (600MHz, CDCl3) δ (ppm): 7.80 (m, 1H), 7.48-7.50 (m, 2H), 7.41 (d, 1H), 7.34 (d, 2H), 7.15 (s, 1H), 7.12(d,4H), 7.10(d,2H), 6.98(d,4H), 6.95(s,1H), 6.89(d,2H), 6.51(s,1H), 2.33(s,6H); 13C NMR (600MHz, CDCl3) δ (ppm): 149.42, 148.66, 144.60, 144.53, 141.58, 139.89, 139.34, 138.27, 137.38 ,137.18,137.15,136.55,135.77,134.95,134.83,134.54,134.13,133.77,133.66,133.59,133.35,1 32.31, 131.53, 130.98, 130.26, 130.21, 129.96, 129.79, 129.03, 128.78, 128.37, 127.66, 125.58, 125 .08, 124.44, 123.89, 122.15, 121.42, 121.22, 119.62, 119.54, 42.76, 42.58, 32.04, 29.82, 21.03; HRMS analysis(APCI):calcd for C 41 H 26 Cl6NO2S(MH) - :805.9821,found:805.9815(error:-0.87ppm).

[0080]

[0081] The reaction was conducted in a glove box in the dark. Compound 4 (25 μmol), potassium tert-butoxide (197 μmol), 18-crown-6 (197 μmol), and anhydrous tetrahydrofuran (10 mL) were added to a 25 mL reaction flask, and the reaction was carried out at room temperature for 5 h. Then, tetrachlorobenzoquinone (197 μmol) was added, and the reaction was continued at room temperature for another 12 h. The reaction was quenched with saturated brine. The mixture was extracted multiple times with dichloromethane, dried, and purified by column chromatography (petroleum ether:dichloromethane = 1:2 as eluent) to give compound 5 as a dark green solid (i.e., the product allyl luminescent radical ARS-TPA(j)) (11 mg, 57%). HRMS analysis (APCI): calcd for C 41 H 26 Cl6NO2S(M)-: 805.9821, found: 805.9819 (error: -0.25ppm). The fluorescence quantum yield is 11.7%, and the half-life under natural light is 27.5 days.

[0082] Example 2

[0083] Synthesis of allyl luminescent radical ARS-Ph(a):

[0084]

[0085] Under nitrogen protection, compound 1 (10.02 mmol), aluminum trichloride (10.22 mmol), and anhydrous dichloromethane (120 mL) were added to a 250 mL reaction flask. The reaction was carried out at 0 °C for 20 min. Then, compound 6 (9.52 mmol) was added to the reaction flask, and the reaction was carried out at room temperature for 2 h. The reaction was quenched with 0.1 M hydrochloric acid (200 mL). The mixture was extracted with dichloromethane, dried, and purified by column chromatography (petroleum ether as eluent). The crude product was then washed with methanol to give compound 7 as a white solid (3.58 g, 60%). 1 H NMR (600MHz, CDCl3) δ (ppm): 7.76 (d, 1H), 7.43 (d, 1H), 7.31-7.33 (t, 2H), 7.30 (s, 4H), 7.14-7.18 (dd, 4H), 6.74 (s, 1H), 2.34 (s, 3H); 13 C NMR (150MHz, CDCl3) δ (ppm): 140.22,139.43,137.67,137.55,137.20,136.73,134.80,133 .68,131.72,129.42,129.39,128.81,124.52,124.34,123.23,122.22,46.14,21.45; HRMS analysis(APCI):calcd forC 28 H 15 Cl6S(MH) - :592.9031,found:592.9030(error:-0.17ppm).

[0086]

[0087] Under nitrogen protection, hydrogen peroxide (41.86 mmol) and anhydrous dichloromethane (100 mL) were added separately to a 250 mL reaction flask. Trifluoroacetic anhydride (62.79 mmol) was added dropwise at 0 °C, and the reaction was carried out at this temperature for 10 min. Then, compound 7 (4.19 mmol) was added, and the reaction was carried out at room temperature for 12 h. The reaction was quenched with saturated Na₂CO₃ solution, the mixture was extracted with dichloromethane, dried, and purified by column chromatography (petroleum ether:dichloromethane = 1:2 as eluent) to give compound 8 as a white solid (2.13 g, 81%). 1H NMR (600MHz, CDCl3) δ (ppm): 7.80 (d, 1H), 7.46-7.51 (m, 3H), 7.46 (s, 2H), 7.10 (s, 2H), 6.88 (d, 2H), 6.67 (d, 2H), 6.52 (s, 1H), 2.32 (s, 3H); 13 CNMR(600MHz, CDCl3)δ(ppm):139.75,139.48,135.90,135.65,133.74,130.02,129.87,12 8.80,128.55,128.33,127.07,126.71,124.34,123.94,121.47,42.40,21.50,21.35.; HRMS analysis(APCI):calcd for C 28 H 15 Cl6O2S(MH) - :624.8929,found:624.8922(error:-1.12ppm).

[0088]

[0089] The reaction was conducted in a glove box in the dark. Compound 8 (0.16 mmol), potassium tert-butoxide (1.27 mmol), 18-crown-6 (1.27 mmol), and anhydrous tetrahydrofuran (40 mL) were added to a 100 mL reaction flask, and the reaction was carried out at room temperature for 5 h. Then, tetrachlorobenzoquinone (1.27 mmol) was added, and the reaction was continued at room temperature for another 12 h. The reaction was quenched with saturated brine, and the mixture was extracted with dichloromethane, dried, and purified by column chromatography (petroleum ether:dichloromethane = 1:2 as eluent) to give compound 9 as a brownish-yellow solid (i.e., the product allyl luminescent radical ARS-Ph(a)) (31 mg, 31%). HRMS analysis (APCI): calcd for C 28 H 15 Cl6O2S(M) - :624.8929,found:624.8926(error:-0.48ppm). The half-life under natural light is 5.2 days.

[0090] Example 3

[0091] Synthesis of allyl luminescent radical ARC-Ph(l):

[0092]

[0093] Under nitrogen protection, compound 1 (0.94 mmol), aluminum trichloride (0.102 mmol), and anhydrous dichloromethane (2 mL) were added to a 25 mL reaction flask. The reaction was carried out at 0 °C for 20 min. Then, compound 10 (0.085 mmol) was added to the reaction flask, and the reaction was carried out at room temperature for 2 h. The reaction was quenched with 0.1 M hydrochloric acid (10 mL). The mixture was extracted with dichloromethane, dried, and purified by column chromatography (eluent: petroleum ether). The crude product was then washed with methanol to give compound 11 as a white solid (39 mg, 75%). 1 HNMR (600MHz, CDCl3) δ (ppm): 7.41 (d, 1H), 7.34 (d, 1H), 7.32 (d, 1H), 7.24 (d, 1H), 7.21 (t, 1H), 7.15 (d, 1H), 7.13 (d, 1H) ),7.04(d,1H),6.76(d,1H),6.71(d,1H),6.58(d,1H),6.45(d,1H),6.15(s,1H),2.30(s,3H),1.56(s,3H),1.28(s,3H); 13 CNMR (150MHz, CDCl3) δ (ppm): 150.42, 141.90, 139.05, 137.63, 136.38, 134.61, 134.52, 132.77, 129.45, 129. 09, 129.01, 128.92, 128.56, 127.38, 121.29, 104.16, 47.13, 31.78, 21.36, 17.15; HRMSanalysis (APCI): calcd for C 31 H 23 Cl6(M+H) + :604.9925,found:604.9929(error:0.66ppm).

[0094]

[0095] The reaction was conducted in a glove box in the dark. Compound 11 (9.9 μmol), potassium tert-butoxide (99 μmol), 18-crown-6 (99 μmol), and anhydrous tetrahydrofuran (5 mL) were added to a 100 mL reaction flask, and the reaction was carried out at room temperature for 5 h. Then, tetrachlorobenzoquinone (99 μmol) was added, and the reaction was continued at room temperature for another 12 h. The reaction was quenched with saturated brine, and the mixture was extracted with dichloromethane, dried, and purified by column chromatography (petroleum ether as eluent) to give compound 12 as a green solid (i.e., the product allyl luminescent radical ARC-Ph(l)) (3 mg, 50%). HRMS analysis (APCI): calcd for C31 H 22 Cl6(M) + :603.9847,found:603.9849(error:0.33ppm).

[0096] Depend on Figure 1 (In the figure, ARS-TPA(j), ARS-Ph(a), and ARC-Ph(l) represent ARS-TPA(j) in Example 1, ARS-Ph(a) in Example 2, and ARS-Ph(l) in Example 3, respectively.) It can be seen that the allyl luminescent radical material exhibits two obvious absorption peaks at 350 nm and 410 nm, and shows a long absorption band characteristic of radicals near 620 nm. After the introduction of donor groups, ARS-TPA shows significantly enhanced absorption, with a maximum absorption wavelength of 770 nm. Its emission spectrum is in the near-infrared region, with a maximum emission wavelength of 843 nm and a half-width of only 50 nm, which is the narrowest among carbon radicals discovered in the near-infrared region.

[0097] Depend on Figure 2 It can be seen that the g value of ARS-Ph(a) is 2.0036.

[0098] Depend on Figure 3 It can be seen that the g value of ARS-TPA(j) is 2.0037.

[0099] Depend on Figure 4 It can be determined that the half-life of ARS-Ph(a) under natural light is 5.2 days.

[0100] Depend on Figure 5 It can be seen that the half-life of ARS-TPA(j) under natural light is 27.5 days.

[0101] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An allyl luminescent free radical material characterized in that, having a structure represented by Formula I: Formula I; wherein • is a radical single electron; R is any one of the following structures: ； X is or .

2. The allyl luminoi free radical material according to claim 1, wherein The allyl luminescent radical material has a structure represented by Formula a to p: 。 3. A process for the preparation of the allyl luminescent free radical material according to claim 1 or 2, characterized in that, When X is a method for preparing an allyl luminescent radical material having a structure represented by Formula I, comprising the following steps: Step 1. Compound 1 is subjected to a Friedel-Crafts alkylation reaction 1 with compound 2 to obtain a Friedel-Crafts alkylation product 1; Step 2. The Friedel-Crafts alkylation product 1 is subjected to an oxidation reaction to obtain an oxidation product; Step 3. The oxidation product is subjected to a dehydrogenation reaction 1 to obtain the allyl luminescent radical material; When X is a method for preparing an allyl luminescent radical material having the structure of Formula I, comprising the steps of: Step S1. Compound 1 is subjected to a Friedel-Crafts alkylation reaction 2 with compound 3 to obtain a Friedel-Crafts alkylation product 2; Step S2. The Friedel-Crafts alkylation product 2 is subjected to a dehydrogenation reaction 2 to obtain the allyl luminescent radical material; The structural formula of the compound 1 is ; The structural formula of the compound 2 is ; The structural formula of the compound 3 is ; In compounds 2 and 3, R is the same as R in Formula I of claim 1.

4. The production method according to claim 3, characterized by, In step 1, the catalyst used in the Friedel-Crafts alkylation reaction 1 is aluminum trichloride, and the solvent is anhydrous dichloromethane; the molar ratio of compound 1 to compound 2 is 1: (0.9-2); the molar ratio of compound 1 to aluminum trichloride is 1:1; the reaction temperature of the Friedel-Crafts alkylation reaction 1 is room temperature, and the reaction time is 1-3 h.

5. The preparation method according to claim 3, characterized in that, In step 2, the oxidant used in the oxidation reaction is peroxotricfluoroacetic acid or m-chloroperbenzoic acid, and the solvent is anhydrous dichloromethane; the molar ratio of the Friedel-Crafts alkylation product 1 to the oxidant peroxotricfluoroacetic acid is 1: (10-15); the molar ratio of the Friedel-Crafts alkylation product 1 to the oxidant m-chloroperbenzoic acid is 1: (4-5); the temperature of the oxidation reaction is room temperature, and the reaction time is 12-14 h.

6. The preparation method according to claim 3, characterized in that, In step 3, the base used in the dehydrogenation reaction 1 is potassium tert-butoxide, the catalyst is 18-crown-6, the solvent is tetrahydrofuran, and the oxidant is tetrachlorobenzoquinone; the molar ratio of the oxidation product, potassium tert-butoxide, 18-crown-6 and tetrachlorobenzoquinone is 1:8:8:8; the temperature of the dehydrogenation reaction 1 is room temperature, and the reaction time is 12 h, avoiding light.

7. The preparation method according to claim 3, characterized in that, In step S1, the catalyst used in the Friedel-Crafts alkylation reaction 2 is aluminum trichloride, and the solvent is anhydrous dichloromethane; the molar ratio of compound 1 to compound 3 is 1: (0.09-0.12); the molar ratio of compound 1 to aluminum trichloride is 1: (0.1-0.2); the reaction temperature of the Friedel-Crafts alkylation reaction 2 is room temperature, and the reaction time is 1-3 h.

8. The preparation method according to claim 3, characterized in that, In step S2, the base used in the dehydrogenation reaction 2 is potassium tert-butoxide, the catalyst is 18-crown-6, the solvent is tetrahydrofuran, and the oxidant is tetrachlorobenzoquinone; the molar ratio of the Friedel-Crafts alkylation product 2, potassium tert-butoxide, 18-crown-6 and tetrachlorobenzoquinone is 1:10:10:10; the temperature of the dehydrogenation reaction 2 is room temperature, and the reaction time is 12 h.

Images