Near-infrared light-emitting diradical materials and preparation and application thereof

Abstract

The application belongs to the field of luminescent materials, and specifically discloses a near-infrared luminescent double free radical material and a preparation and application thereof.The near-infrared luminescent double free radical material has a structure of formula 1, and the application further includes a preparation method and application of the compound.The novel compound disclosed by the application can improve the air and light stability of the molecule in a synergistic manner based on the combined synergy of the molecular structure, can further adjust the excited state electron structure and symmetry of the double free radical material, and can further control the emission wavelength.The application provides a high-stability and high-efficiency near-infrared luminescent free radical material, the material has the characteristics of near-infrared emission and large Stokes shift, and has the ability to generate superoxide free radical anions, and can be prepared into nanoparticles and applied to fluorescence imaging and photodynamic therapy.

Description

Technical Field

[0001] This invention relates to the field of luminescent materials and bioimaging, specifically to the field of small molecule luminescent materials. Background Technology

[0002] Radical materials, possessing unpaired or weakly bonding electrons, exhibit unique optical, electrical, and magnetic properties, attracting widespread attention from researchers in organic electronics, nonlinear optics, spintronics, and energy storage devices. Due to spin selectivity limitations, traditional fluorescent molecules can only generate 25% of singlet excitons for luminescence; however, luminescent radical molecules have doublet states in both their ground and excited states, eliminating transition forbidden issues during luminescence and theoretically favoring exciton radiative transitions for highly efficient fluorescence. However, most organic radicals are typically non-luminescent due to strong nonradiative relaxation pathways in their photoexcited states. In recent years, luminescent organic radicals, represented by tris(2,4,6-trichlorophenyl)methyl (TTM) radicals, have emerged. These materials overcome the 75% energy loss of first-generation organic light-emitting diodes (OLEDs) based on traditional closed-shell luminescent materials, becoming a new generation of molecular luminescent materials. This dual-state monopolar structure can achieve 100% exciton utilization in OLEDs, sparking researchers' interest in exploring next-generation radical-based luminescent materials.

[0003] Recent significant progress has been made in the steric design of triarylmethyl radicals based on the polychlorinated aryl groups surrounding the spin-confined center (A·). Related structural modifications and research have primarily focused on desymmetry of the polychlorinated triphenylmethyl radical nucleus, specifically C3 symmetry, leading to symmetry-forbidden D-D1 transitions. When the π-unit is covalently linked to an aromatic amine / carbazole group rather than an aryl group, DA·-type dual emitters typically exhibit intramolecular charge-transfer excitation, thus these molecules emit light in the red or near-infrared spectral region (~700 nm). However, luminescence is rarely observed in dual radicals based on the π-conjugation extension of triarylmethyl groups. Therefore, there is an urgent need to develop a radical material with high stability, near-infrared luminescence, and high luminescence efficiency to overcome the shortcomings of traditional dual radical materials, such as their difficulty in luminescence. Summary of the Invention

[0004] To address the problems of existing technologies, the primary objective of this invention is to provide a near-infrared luminescent dual radical material (also referred to as radical molecular material), aiming to provide a new material that balances excellent stability with luminescent properties and effects.

[0005] The second objective of this invention is to provide a method for preparing the near-infrared luminescent dual radical material, thereby successfully preparing the novel compound.

[0006] A third objective of this invention is to provide the application of the aforementioned near-infrared luminescent dual radical material in bioimaging.

[0007] Free radical compounds are generally unstable and lack luminescence properties. To address this issue, this invention, through in-depth research, provides the following innovative solutions:

[0008] A near-infrared luminescent dual radical material having the structure of Formula 1:

[0009]

[0010] In Formula 1, R1, R2, R3, R4, R5, R6, and R7 are individually H, -Cl, -Br, -I, -CN, -CF3, Cl-C, etc. 24 Alkyl, C3-C 24 cycloalkyl, C1-C 24 Alkoxy, C6-C 24 aryl or substituted aryl, halogenated C1-C 24 Alkyl, halogenated C3-C 24 Cycloalkyl or halogenated C1-C 24 Alkoxy, ester, aminoacyl, or -NO2;

[0011] Alternatively, the adjacent substituents R1, R2, R3, and R4 may cyclize with the benzene ring to form an aromatic or non-aromatic cyclic structure.

[0012] The Ar is a benzene ring, a five-membered heteroaryl ring, a six-membered heteroaryl ring, or a fused aromatic ring formed by the fusion of two or more aromatic rings from the benzene ring, five-membered heteroaryl ring, or six-membered heteroaryl ring.

[0013] The aromatic ring of Ar may or may not have substituents; the substituents are at least one selected from alkoxy, nitro, halogen, phenyl, cycloalkyl, -CN, and -OTf.

[0014] This invention provides a novel material with a tautomerism of Formula 1. Studies have shown that the novel radical compound of this invention, based on the synergistic effect of its molecular structure and functional groups, can achieve significant improvements in its air and photostability. Furthermore, it endows the compound with excellent luminescent properties, particularly enabling it to emit light in the rarely seen near-infrared region. Therefore, due to the excellent stability and unique luminescent properties of the compound of this invention, it has broad application prospects in the fields of photodynamic therapy and the development of light-emitting devices.

[0015] This invention reveals that the structure of the compound and the introduction of sulfone groups are key to synergistically improving the stability and luminescence efficiency of the radical material. The described molecular structure can synergistically weaken the delocalization of spin electrons, increase structural rigidity, suppress nonradiative relaxation pathways of the photoexcited state to a certain extent, and improve luminescence efficiency; furthermore, it can regulate the excited-state electronic structure and emission wavelength.

[0016] In this invention, R1, R2, R3, R4, R5, R6, and R7 are individually H, CN, CF3, and Cl-C, respectively. 24 Alkyl, C3-C 24 Cycloalkyl or C1-C 24 Alkoxy;

[0017] Preferably, R1, R2, R3, and R4 are H, -CN, or -CF3;

[0018] Preferably, the cyclic structure (containing a cyclic benzene ring) can be a fluorene ring, a naphthalene ring, or a thiafluorene ring;

[0019] Preferably, R5, R6, and R7 are H or C1-C4 alkoxy groups.

[0020] Further preferably, R3 is an electron-withdrawing group, preferably -CN or -CF3; and R1, R2, R4, R5, R6, and R7 are H. Studies have found that compounds with this preferred structure can further improve the air and light stability of the diradical compound, and also improve its luminescent properties.

[0021] In this invention, Ar is phenyl or anthracene; or phenyl or anthracene substituted with at least one of the following groups: halogen, C1-C6 alkyl, C1-C6 alkoxy, phenyl, or substituted phenyl.

[0022] Furthermore, Wherein, R is a C1-C2 alkyl group, a C1-C2 alkoxy group, or a halogen.

[0023] In this invention, the near-infrared luminescent dual radical material is a compound having the following structure:

[0024]

[0025] The present invention also provides a method for preparing the near-infrared luminescent dual radical material, which is obtained by oxidative coupling of the compound of formula 2 and an oxidant;

[0026]

[0027] In Equation 2, the selection ranges of R1, R2, R3, R4, R5, R6, R7, and Ar are the same as in Equation 1;

[0028] In this invention, as an example of an embodiment, the oxidant may be at least one of ferric chloride, DDQ, and tetrachloro-p-benzoquinone;

[0029] Preferably, in the oxidative coupling, the molar ratio of Formula 2 to the oxidant is 1:1.5 to 2.5;

[0030] Preferably, the reaction temperature for oxidative coupling is 15–40°C;

[0031] Preferably, the solvent for oxidative coupling is one of THF, Et3N, and DCM;

[0032] Preferably, in the oxidative coupling stage, Formula 2 and an organic base are mixed beforehand, and then an oxidant is added to carry out the oxidative coupling reaction, followed by separation by column chromatography to obtain Formula 1.

[0033] The organic base can be a C1-C6 alkoxide, preferably at least one of a C1-C6 sodium alkoxide or a C1-C6 potassium alkoxide. Further, the molar ratio of Formula 2 and the organic base is 1:1.0-2.5.

[0034] In this invention, the compound of formula 2 is prepared by oxidation reaction of formula 3:

[0035]

[0036] In Equation 3, the selection ranges of R1, R2, R3, R4, R5, R6, R7, and Ar are the same as in Equation 1;

[0037] The oxidant a selected in the oxidation reaction stage includes, but is not limited to, at least one of peroxides and persulfates. As an example, it can be m-chloroperoxybenzoic acid.

[0038] Preferably, in the oxidation reaction, the molar ratio of formula 3 to oxidant a is 1:2 to 4;

[0039] Preferably, the solvent for the oxidation reaction is one of THF, Et3N, or DCM;

[0040] Preferably, the oxidation reaction temperature is 15℃~40℃.

[0041] In this invention, Formula 3 is prepared by reacting a compound of Formula 4, an alkyllithium compound, and a halogenated aromatic compound with the expression Ar-X:

[0042]

[0043] In Equation 4, the selection ranges of R1, R2, R3, R4, R5, R6, and R7 are the same as in Equation 3;

[0044] Preferably, X is a halogen, and more preferably Br;

[0045] Preferably, the molar ratio of the halogenated aromatic compound to Formula 4 is 0.8 to 1:1;

[0046] Preferably, the alkyl lithium is a C2-C8 alkyl lithium, and more preferably n-butyl lithium;

[0047] Preferably, the molar ratio of alkyllithium to Formula 4 is 1 to 1.2:1;

[0048] Preferably, the solvent for the reaction is one of THF, Et3N, DCM, and DCE;

[0049] Preferably, the reaction temperature is below -10°C, and more preferably below -40°C.

[0050] This invention provides an application of the aforementioned near-infrared luminescent dual radical material for the preparation of semiconductor electronic devices, bioimaging, spin materials, and near-infrared light-excited photodynamic therapy nanomedicines.

[0051] Further preferred applications include using the aforementioned free radical molecular material in organic light-emitting diodes, biofluorescent probes, photodynamic therapy, etc.

[0052] The present invention also provides a near-infrared light-emitting device comprising the aforementioned near-infrared light-emitting dual radical material.

[0053] The present invention also provides a near-infrared light-excited photodynamic therapeutic nanomedicine, which comprises a pharmaceutically effective amount of the aforementioned near-infrared luminescent dual radical material.

[0054] The drug described in this invention can be prepared into any drug delivery formulation capable of phototherapy based on known formulation methods and excipients using the near-infrared luminescent dual radical material described in this invention.

[0055] The technical solution of this invention has the following beneficial effects:

[0056] This invention provides a material with a novel structure, which, based on the synergy of molecular structure and functional groups, can achieve synergy and significantly improve the air stability and light stability of the free radical compound. In addition, it also has excellent luminescent properties, especially the ability to emit light in the rare near-infrared region.

[0057] The free radical luminescent material described in this invention has deep near-infrared emission and large Stokes shift characteristics, and also has the ability to generate superoxide radical anions, showing great application potential in photodynamic therapy. Attached Figure Description

[0058] Figure 1 This is the 1H NMR spectrum of compound 5 obtained in Example 2.

[0059] Figure 2 This is the carbon NMR spectrum of compound 5 obtained in Example 2.

[0060] Figure 3 This is the mass spectrum (Mw = 560.7) of compound 5 obtained in Example 2.

[0061] Figure 4 This is the 1H NMR spectrum of compound 6 obtained in Example 2.

[0062] Figure 5 This is the carbon NMR spectrum of compound 6 obtained in Example 2.

[0063] Figure 6 This is the mass spectrum (Mw = 554.7) of compound 6 obtained in Example 2.

[0064] Figure 7 This is the variable-temperature nuclear magnetic resonance hydrogen spectrum of compound SD-2 obtained in Example 2.

[0065] Figure 8 This is the mass spectrum (Mw = 1181.3) of compound SD-2 obtained in Example 2.

[0066] Figure 9 The UV-vis-NIR absorption spectra (A) and photoluminescence spectra (B) of compounds SD-1 to SD-3 obtained in Examples 1 to 3 in toluene are shown.

[0067] Figure 10 These are the single-crystal stacked structures of compounds SD-1 to SD-3 obtained in Examples 1 to 3.

[0068] Figure 11 The stability of SD-1 to SD-3 prepared in Examples 1 to 3 in air and toluene solution is monitored.

[0069] Figure 12 The stability of SD-1 to SD-3 prepared in Examples 1 to 3 under air, toluene solution and continuous light exposure was monitored.

[0070] Figure 13 The absorption and emission spectra of SD-2@DSPE-PEG prepared in Example 5 are shown in aqueous solution.

[0071] Figure 14 The confocal fluorescence image (a) and shortwave infrared image (b) of SD-2@DSPE-PEG prepared in Example 5 in mice are shown. Detailed Implementation

[0072] The technical solution of the present invention will be further illustrated below through specific experimental methods.

[0073] Unless otherwise specified, the experimental methods described in the following examples are conventional methods, and the reagents and materials described are commercially available unless otherwise specified.

[0074] Example 1 Synthesis of SD-1

[0075]

[0076] Compound 1 (595 mg, 3.00 mmol) was added to a dry 200 mL Shrek flask, followed by 60 mL of dry tetrahydrofuran under an argon atmosphere. The flask was cooled to -40 °C, and then a solution of n-butyllithium in n-hexane (1.2 mL, 3.00 mmol) was slowly added dropwise. The mixture was stirred at -40 °C for 1 hour. Then, 9-bromo-10-trimethylanthracene (935 mg, 2.50 mmol) was dissolved in 30 mL of tetrahydrofuran and added to the flask. The reaction mixture was slowly brought to room temperature and stirred at room temperature, with the reaction monitored by TLC. After the reaction was complete, 10 mL of water was added to quench the reaction, and the mixture was extracted five times with 40 mL of dichloromethane. The organic layers were combined, washed three times with 50 mL of water, dried over anhydrous sodium sulfate, filtered, and the solvent was removed from the filtrate using a rotary evaporator to obtain a white crude product. The crude product was further separated and purified by silica gel column chromatography with petroleum ether:dichloromethane = 10:1 as the eluent, yielding 788 mg of white solid compound 2, with a yield of 64%.

[0077] 1 H-NMR (400MHz, CDCl3): δ8.43(s,1H),7.73–7.62(m,3H),7.54(d,J=7.8Hz,2H),7.47–7.33(m,2H),7.19–7.15( m,5H),7.06–6.97(m,1H),6.88(t,J=7.6Hz,2H),6.53(s,1H),6.48(d,J=7.9Hz,2H),2.51(s,3H),1.86(s,6H).

[0078] 13 C-NMR (100Hz, CDCl3): δ138.22,137.49,137.25,137.23,134.85,131.92,130.09,128.75,128.33,126.58,126.16,126.06,45.15,21.28,20.12.

[0079] HRMS(MALDI-TOF)m / z:Calcd for C 36 H 28 S+ [M] + ,492.1912; Found:492.1905(error=-1.4ppm).

[0080] Compound 2 (591 mg, 1.2 mmol) was added to a 100 mL single-necked flask and dissolved in 30 mL of dichloromethane. After complete dissolution, 3-chloroperoxybenzoic acid (619 mg, 3.6 mmol) was added to the flask, and the mixture was stirred at room temperature for 4 hours. The pH of the reaction solution was adjusted to 7.0 by adding 2 M Na₂CO₃ aqueous solution. The mixture was then extracted three times with 40 mL of dichloromethane. The organic phases were combined, washed three times with 50 mL of water, dried over anhydrous Na₂SO₄, filtered, and the solvent was removed from the filtrate using a rotary evaporator to obtain a white crude product. The crude product was further purified by silica gel column chromatography with petroleum ether:dichloromethane = 1:1 as the eluent to give 560 mg of white solid compound 3, with a yield of 89%.

[0081] 1 H NMR (400MHz, CDCl3): δ8.46(d,J=9.1Hz,1H),8.34–8.31(m,2H),7.68(d,J=8.7Hz,1H),7.60–7.46(m,4H),7.43–7.39 (m,1H),7.25–7.12(m,6H),6.96–6.91(m,1H),6.84(d,J=8.9Hz,1H),6.57(d,J=8.0Hz,2H),2.49(s,3H),1.83(s,6H).

[0082] 13 C NMR (100Hz, CDCl3): δ141.62,138.36,137.49,137.30,136.18,132.50,132.20,130.33,129.84,129.27,129.00,128 .42,128.16,128.00,127.57,127.48,127.26,127.21,125.69,125.11,125.02,123.51,123.03,40.81,21.26,20.09.

[0083] HRMS(MALDI-TOF)m / z:Calcd for C 36 H 28 O2S + [M] + ,524.1810; Found:524.1823(error=2.5ppm).

[0084] Compound 3 (262 mg, 0.50 mmol) was added to a 50 mL dry Shrek flask and dissolved in 20 mL of anhydrous tetrahydrofuran. Under an argon atmosphere, potassium tert-butoxide (112 mg, 1.00 mmol) was added to the reaction flask, and the mixture was stirred at room temperature. The reaction was monitored using UV-Vis absorption spectroscopy. After 3 hours, all starting materials disappeared, forming a dark brown anionic solution. Then, under argon protection, p-chloramine (185 mg, 0.75 mmol) was added to the reaction flask, turning the solution deep blue. The reaction was monitored by TLC. After the reaction was complete, the reaction solution was transferred to a 50 mL single-necked flask, and the solvent was removed by rotary evaporation to obtain a blue crude product. The crude product was further purified by silica gel column chromatography with petroleum ether:tetrahydrofuran = 5:1 as the eluent, yielding 371 mg of a white solid, compound SD-1, in 71% yield.

[0085] HRMS(MALDI-TOF)m / z:Calcd for C 72 H 52 O4S2 + [M] + ,1044.3307; Found:1044.3315(error=0.8ppm).

[0086] Example 2: Synthesis of SD-2

[0087]

[0088] Compound 8 was synthesized according to the method for compound 2 in Example 1, with a yield of 69%.

[0089] 1 H NMR (400MHz, CDCl3): δ8.38(s,1H),7.73–7.42(m,6H),7.40–7.32(m,2H),7.25–7.12(m,4H),7.06(s, 1H),6.94(t,J=7.6Hz,1H),6.62(d,J=7.9Hz,1H),6.52(s,2H),2.49(s,3H),1.87(s,3H),1.76(s,3H).

[0090] 13C NMR (100MHz, CDCl3): δ138.94,137.81,137.34,137.29,136.77,134.72,130.63,128.94,128.33,128.01,127.25 ,127.05,126.79,126.35,126.10,125.52,125.48,125.30,125.11,123.38,123.34,122.41,45.06,21.28,19.82.

[0091] HRMS(MALDI-TOF)m / z:Calcd for C 37 H 27 F3S + [M] + ,560.1786; Found:560.1779(error=-1.2ppm).

[0092] Compound 9 was synthesized according to the method for compound 3 in Example 1, with a yield of 84%.

[0093] 1 H NMR (400MHz, CDCl3): δ8.43(d,J=8.6Hz,2H),8.35(d,J=7.8Hz,1H),8.10–7.9 8(m,1H),7.72(t,J=8.5Hz,2H),7.60–7.53(m,3H),7.46–7.42(m,3H),7.31(t ,J=7.8Hz,1H),7.20–7.14(m,3H),6.95(t,J=7.7Hz,1H),6.78(d,J=8.0Hz,1H ),6.69(d,J=8.9Hz,1H),6.63(s,1H),2.49(s,3H),1.89(s,3H),1.72(s,3H).

[0094] 13C NMR (100Hz, CDCl3): δ170.26,143.03,141.17,139.56,138.96,137.58,137.40,137.06,135. 48,134.66,134.29,134.06,133.80,133.07,132.22,130.97,130.36,130.22,129.82,129.17 ,129.01,128.59,128.33,128.27,128.01,127.59,127.54,127.43,127.25,126.81,126.19,125.81,125.53,125.26,124.53,124.28,123.87,122.75,121.33,40.98,21.27,20.11,19.58.

[0095] HRMS(MALDI-TOF)m / z:Calcd for C 37 H 27 F3O2S + [M] + ,592.1684; Found:592.1672(error=-2.0ppm).

[0096] Compound SD-2 was synthesized according to the method for compound SD-1 in Example 1, with a yield of 62%.

[0097] HRMS(MALDI-TOF)m / z:Calcd for C 37 H 30 O3S + [M] + ,1180.3055; Found:1180.3046(error=-0.7ppm).

[0098] Example 3: Synthesis of SD-3

[0099]

[0100] Compound 8 was synthesized according to the method for compound 2 in Example 1, with a yield of 63%.

[0101] 1 H NMR (400MHz, CDCl3): δ8.45 (d, J = 7.8Hz, 2H), 7.61 (d, J = 8.0Hz, 3H), 7.51-7.44 (m, 7H), 7.37 (t, J = 7.6Hz, 4H), 7.09 (d, J = 7.9Hz, 3H), 2.90 (s, 1H).

[0102] 13 C NMR (100MHz, CDCl3): δ158.28,140.01,138.08,137.42,137.27,137.23,134.85,132.59,129.93,12 8.78,128.34,126.77,126.57,126.10,126.05,122.95,115.02,112.53,54.74,45.52,21.28,20.00.

[0103] HRMS(MALDI-TOF)m / z:Calcd for C 37 H 30 OS + [M] + ,522.2017; Found:522.2012(error=-1.0ppm).

[0104] Compound 9 was synthesized according to the method for compound 3 in Example 1, with a yield of 87%.

[0105] 1 H NMR (400MHz, CDCl3): δ8.43(d,J=8.6Hz,2H),8.35(d,J=7.8Hz,1H),8.10–7.9 8(m,1H),7.72(t,J=8.5Hz,2H),7.60–7.53(m,3H),7.46–7.42(m,3H),7.31(t ,J=7.8Hz,1H),7.20–7.14(m,3H),6.95(t,J=7.7Hz,1H),6.78(d,J=8.0Hz,1H ),6.69(d,J=8.9Hz,1H),6.63(s,1H),2.49(s,3H),1.89(s,3H),1.72(s,3H).

[0106] 13C NMR (100Hz, CDCl3): δ170.50,162.40,143.96,141.26,138.29,137.48,137.25,137.16,13 6.62,134.64,134.43,133.80,132.28,132.17,130.97,130.26,130.20,129.81,129.74,12 9.27, 128.98, 128.43, 128.27, 128.21, 128.07, 127.55, 127.39, 127.22, 127.11, 125.70, 125.62, 125.14, 125.06, 123.15, 123.03, 114.62, 112.97, 54.96, 41.04, 21.25, 20.09, 19.84.

[0107] HRMS(MALDI-TOF)m / z:Calcd for C 37 H 30 O3S + [M] + ,554.1916; Found:554.1920 (error=0.7ppm).

[0108] Compound SD-3 was synthesized according to the method for compound SD-1 in Example 1, with a yield of 35%.

[0109] HRMS(MALDI-TOF)m / z:Calcd for C 37 H 30 O3S + [M] + ,1104.3518; Found:1104.3525(error=0.6ppm).

[0110] Example 4: Property Verification Based on SD-1 to SD-3

[0111] In this invention, the structures of SD-1 to SD-3 were confirmed by means of variable-temperature nuclear magnetic resonance hydrogen spectroscopy, mass spectrometry, ultraviolet-visible-near-infrared absorption spectroscopy, and single-crystal diffraction, and their related properties were studied.

[0112] Figure 9The UV-Vis-NIR absorption spectra (A) and photoluminescence spectra (B) of toluene solutions of compounds SD-1 to SD-3 are shown in Table 1. The related photophysical properties are also presented. Electronic absorption spectroscopy results show that the maximum absorption wavelength of compounds SD-1 and SD-2 is 625 nm, while the absorption band of compound SD-3 exhibits a redshift of approximately 42 nm, with a maximum absorption wavelength of 657 nm. Calculations yielded photoluminescence quantum yields (PLQY) of compounds SD-1 to SD-3 of 5.2%, 2.4%, and 2.0%, respectively, indicating that the donor / acceptor substituents in these sulfone-functionalized diradical compounds play a crucial role in their radiative decay process.

[0113] Table 1. Photophysical properties of SD-1 to 3 in toluene

[0114]

[0115] Figure 10 The diagrams show the single-crystal structures of SD-1 to SD-3. All compounds SD-1 to SD-3 consist of two triarylmethyl segments, each composed of three orthogonally arranged segments: a sulfone-intercalated π-segment, an anthracene segment, and a mesityleline segment. The C / C bond lengths connecting the two half-molecule segments in SD-1, SD-2, and SD-3 are 1.418, 1.424, and 1.424, respectively. The dihedral angles between faces A and B in SD-1, SD-2, and SD-3 are 5.0°, 0.2°, and 26.3°, respectively; the molecular structures of SD-1 to 3 all exhibit approximately C2 symmetry.

[0116] Air stability assessment:

[0117] SD-1 to SD-3 molecules were dissolved in toluene to obtain homogeneous solutions (the concentration of each solute was 10). -5 M), the homogeneous solution was placed in an air environment; and the decomposition of SD-1 to SD-3 molecules was tested by ultraviolet light.

[0118] Light stability assessment:

[0119] SD-1 to SD-3 molecules were dissolved in toluene to obtain a homogeneous solution (the concentration of the solute was 0.1 M). The homogeneous solution was irradiated with light in the 365 nm band, and the decomposition of SD-1 to SD-3 molecules was tested by ultraviolet light.

[0120] The stability of SD-1 to SD-3 molecules in solution under air and light conditions can be demonstrated by their ultraviolet absorption monitoring graphs. For example... Figure 11 As shown, the half-life of three diradical molecules in an air environment can reach up to 70 days; Figure 12 As shown, their half-lives all reach 10 under light. 4s or more.

[0121] Example 5: Synthesis and Property Verification of SD-2@DSPE-PEG

[0122] This invention is based on the synthesis and property study of SD-2@DSPE-PEG. The specific synthesis method is as follows:

[0123] (1) Preparation of SD-2@DSPE-PEG nanoparticles (also known as SD-2NPS):

[0124] Based on the direct synthesis of SD-2@DSPE-PEG nanoparticles using a nano-coprecipitation method, firstly, 1 mL of THF stock solution containing SD-2 (100 μg) and distearate phosphatidylethanolamine-polyethylene glycol 5000 (DSPE-mPEG 5k) (2.5 mg) was prepared. 9 mL of H2O was placed in a round-bottom flask, and the prepared tetrahydrofuran solution was quickly injected and sonicated for 8 minutes. After removing THF using a rotary evaporator, the mixture was centrifuged (4500 rpm, 5 min), washed with deionized water, and finally concentrated. The concentration was determined using SD-2 (SD-2 concentration is 1 g / L), and the mixture was stored in the dark.

[0125] (2) Properties of SD-2@DSPE-PEG

[0126] Figure 13 The absorption (SD-2NPS-Abs) and emission (SD-2NPS-PL) spectra of SD-2@DSPE-PEG prepared in Example 5 in aqueous solution are shown. Figure 13 It can be observed that SD-2@DSPE-PEG has a distinct emission peak at 901nm.

[0127] Figure 14 The images show confocal fluorescence images (a) of HeLa cells treated with SD-2@DSPE-PEG (10 μg / mL) under 660 nm light irradiation in the presence of DHE, and short-wave infrared images (b) of SD-2@DSPE-PEG (right) and blank (left) under 660 nm excitation in mice. SD-2@DSPE-PEG exhibits excellent intracellular reactive oxygen species (ROS) generation capacity under light irradiation. The presence of 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA, ROS) indicator 22 and dihydrooxoic acid (DHE, superoxide) 23 in HeLa cells further confirms the presence of SD-2@DSPE-PEG, making it suitable for short-wave infrared excitation at 660 nm.

[0128] In summary, the compound of Formula 1 described in this invention has deep near-infrared emission and large Stokes shift characteristics, and also has the ability to generate superoxide radical anions, which has great application potential in photodynamic therapy.

Claims

1. A near-infrared luminescent dual-radical material, characterized in that, It has the structure of Equation 1; Formula 1 In Equation 1, R3 is H or -CF3; R6 is H or C1-C4 alkoxy group; R1, R2, R4, R5, and R7 are H; The Ar is a trimethylbenzyl or a trichlorophenyl-substituted anthracene group.

2. The near-infrared luminescent dual-radical material as described in claim 1, characterized in that, Compounds having the following structures: 。 3. A method for preparing a near-infrared luminescent dual-radical material according to any one of claims 1 to 2, characterized in that, The compound of formula 2 was oxidatively coupled with an oxidizing agent to obtain the product of formula 1. Formula 2 In Equation 2, the selection ranges of R1, R2, R3, R4, R5, R6, R7, and Ar are the same as in Equation 1.

4. The method for preparing the near-infrared luminescent dual-radical material as described in claim 3, characterized in that, The oxidant added in the oxidative coupling is at least one of ferric chloride, DDQ, and tetrachloro-p-benzoquinone; In oxidative coupling, the molar ratio of Formula 2 to the oxidant is 1:1.5~2.5; The reaction temperature for oxidative coupling is 15~40℃; The solvent for oxidative coupling is one of THF, Et3N, or DCM.

5. The method for preparing the near-infrared luminescent dual-radical material as described in claim 4, characterized in that, In the oxidative coupling stage, Formula 2 and an organic base are mixed beforehand, and then an oxidant is added to carry out the oxidative coupling reaction. Subsequently, Formula 1 is obtained by column chromatography. The organic base is a C1-C6 alkoxide; The molar ratio of Formula 2 and organic base is 1:1.0~2.

5.

6. The preparation method according to claim 3, characterized in that, Compound of Formula 2 is prepared by oxidation reaction of Formula 3: Formula 3 In Equation 3, the selection ranges of R1, R2, R3, R4, R5, R6, R7, and Ar are the same as in Equation 1.

7. The preparation method according to claim 6, characterized in that, The oxidant a selected in the oxidation reaction stage includes at least one of peroxides and persulfates; In the oxidation reaction, the molar ratio of Equation 3 to oxidant a is 1:2~4; The solvent for the oxidation reaction is one of THF, Et3N, or DCM; The oxidation reaction occurs at temperatures ranging from 15°C to 40°C.

8. The preparation method according to claim 6, characterized in that, Formula 3 is prepared by reacting a compound of Formula 4, an alkyllithium compound, and a halogenated aromatic compound with the expression Ar-X: Formula 4 In Equation 4, the selection range of R1, R2, R3, R4, R5, R6, and R7 is the same as that in Equation 3.

9. The preparation method according to claim 8, characterized in that, X is a halogen; The molar ratio of the haloaromatic compound to Formula 4 is 0.8 to 1:1; The alkyl lithium is a C2-C8 alkyl lithium; The molar ratio of alkyllithium to formula 4 is 1~1.2:1; The solvent for the reaction is one of THF, Et3N, DCM, or DCE; The reaction temperature is below -10℃.

10. An application of the near-infrared luminescent dual-radical material according to any one of claims 1 to 2, characterized in that, Used to prepare at least one of semiconductor electronic devices, bioimaging, spin materials, and near-infrared light-excited photodynamic therapy nanomedicines.

11. A near-infrared light-emitting device, characterized in that, It includes the near-infrared luminescent dual radical material as described in any one of claims 1 to 2.

12. A near-infrared light-excited photodynamic therapy nanomedicine, characterized in that, The near-infrared luminescent dual radical material comprising a pharmaceutically effective amount as described in claims 1-2.

Images