Carbazole-based small molecule compounds, methods, and organic all-photosynapses based on a light history-dependent fluorescence intensity mechanism.

Abstract

This invention discloses a small molecule compound based on carbazole, the general structural formula of which is shown in Formula I: wherein, in Formula I, R 1 R 2 and R 3 Each independently represents hydrogen, C1-C 30 Alkyl, C1-C 30 alkoxy groups, C6-C 30 Aryl, 5-30 membered heteroaryl, halogen; n is an integer greater than or equal to 4 and less than 20, X represents a heteroelement of group VIA, such as oxygen, sulfur, selenium, or tellurium. This invention is based on the anti-Carbazole dual-fluorescence emission of a small organic molecule, with fluorescence intensity correlated with light history. It achieves neural synaptic behaviors such as post-stimulation light intensity, double-pulse facilitation, and the transition from short-range plasticity to long-range plasticity. This is the first organic all-optical synaptic device and can be applied to fields such as associative learning, memory imaging, and machine learning.

Description

Technical Field

[0001] This invention belongs to the field of organic all-optical synaptic device technology, and in particular to an organic all-optical synapse based on a small molecule compound of carbazole, a method, and an organic all-optical synapse based on a light history-dependent fluorescence intensity mechanism. Background Technology

[0002] Artificial intelligence (AI) is the science of studying and developing intelligent machines to simulate and extend human intelligence. For example, traditional von Neumann computers, due to their separate processors and memory, have limited operating speed and consume a lot of energy. However, the human brain can process and remember information simultaneously by manipulating synaptic weights. Therefore, simulating synaptic behavior in the brain may be a way to overcome the von Neumann bottleneck.

[0003] Organic materials, with their advantages of ease of modification, low cost, and mechanical flexibility, have been used in artificial synaptic devices to simulate synaptic plasticity under different stimuli. Importantly, compared to inorganic synaptic devices, organic synaptic devices have lower energy consumption, with driving voltages as low as 10 kJ / L. -5 V can even be zero. However, electrical devices inevitably incur additional electrical consumption and Joule heat, and are limited by device size. To address this issue, all-optical synapses, where both input and output signals are optical quantities, have emerged. Currently, all-optical synapses primarily utilize inorganic materials to modulate transmittance or long afterglow characteristics under illumination. Organic all-optical synapses have never been reported because it is difficult to obtain optical variables related to irradiation history in organic molecules.

[0004] A search revealed no patent publications related to this invention's patent application. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a small molecule compound based on carbazole, a method, and an organic all-photosynapse based on a light history-dependent fluorescence intensity mechanism.

[0006] The technical solution adopted by this invention to solve its technical problem is:

[0007] A small molecule compound based on carbazole, the general structural formula of which is shown in Formula I:

[0008]

[0009] In the structural formula I, R 1 R 2 and R 3 Each independently represents hydrogen, C1-C 30 Alkyl, C1-C 30 alkoxy groups, C6-C 30Aryl, 5-30 heteroaryl, halogen; n is an integer greater than or equal to 4 and less than 20, and X represents a heteroelement of group VIA.

[0010] Furthermore, in structural formula I, R 1 Indicates hydrogen or C1-C 30 Alkyl or halogen, R 2 Indicates hydrogen or C1-C 30 Alkyl or halogen, R 3 X represents hydrogen or halogen, and X represents sulfur.

[0011] Furthermore, in structural formula I, R 1 R represents hydrogen or a C1-C6 straight-chain alkyl group or halogen. 2 R represents hydrogen or a C1-C6 straight-chain alkyl group or halogen. 3 X represents hydrogen or chlorine, and X represents sulfur.

[0012] Furthermore, the luminescence properties of the small molecule compound are as follows: it exhibits anti-Kasha fluorescence dual emission phenomenon; the short-wavelength emission peak of the small molecule compound has a light history-dependent luminescence intensity characteristic.

[0013] Furthermore, the general structural formula of the small molecule compound is shown in Formula II:

[0014]

[0015] Furthermore, the alkyl group includes branched and straight-chain saturated aliphatic hydrocarbon groups having a specified number of carbon atoms;

[0016] The alkoxy group is -O-alkyl;

[0017] The aryl group is a monocyclic, bicyclic, or tricyclic ring system having a total of 5 to 12 ring members, wherein at least one ring in the system is aromatic and wherein each ring in the system contains 3 to 7 ring members.

[0018] The heteroaryl group is a stable 3-membered, 4-membered, 5-membered, 6-membered, or 7-membered aromatic monocyclic or aromatic bicyclic or 7-membered, 8-membered, 9-membered, 10-membered, 11-membered, or 12-membered aromatic polycyclic heterocyclic ring, which is completely unsaturated or partially unsaturated, and contains a carbon atom and one, two, three, or four heteroatoms independently selected from N, O, and S; and includes any kind of polycyclic group, wherein any heterocycle is fused with a benzene ring.

[0019] Furthermore, C1-C6 alkyl refers to alkyl groups having 1 to 6 carbon atoms, including methyl, ethyl, propyl, butyl, and pentyl;

[0020] C1-C 30Alkyl groups refer to alkyl groups with 1 to 30 carbon atoms, including straight-chain or branched alkyl groups. Straight-chain alkyl groups include methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecanyl, n-hexadecyl, n-heptadecyl, and n-octadecyl. Branched alkyl groups include C8-C30 branched alkane groups, including 2-ethylhexyl, 2-ethyloctyl, 2-butylhexyl, 2-hexyloctyl, 4-hexyldecyl, 3-hexylundecyl, 2-octyldecyl, 2-octyldodecyl, 3-octyltridecyl, 2-decyldodecyl, 2-decyltetradecyl, 2-decyltetradecyl, 3-decylpentadecanyl, 2-dodecylhexadecyl, 4-octyltetradecyl, 4-decylhexadecyl, 4-hexyldecyl, 4-octyldodecyl, 4-decyltetradecyl, and 4-dodecylhexadecyl.

[0021] C1-C6 alkoxy groups include C1, C2, C3, C4, C5, and C6 alkoxy groups, including methoxy, ethoxy, propoxy, and tert-butoxy groups; straight-chain alkoxy groups are C1-C6. 12 Alkyl groups include: methoxy, ethoxy, propoxy, n-butoxy, n-pentoxy, n-hexoxy, n-heptoxy, n-octoxy, n-nonoxy, n-decoxy, n-undecyloxy, and n-dodecyloxy; branched alkoxy groups are C8-C. 30 Branched alkoxy groups include: 2-ethylhexyloxy, 2-ethyloctyloxy, 2-butylhexyloxy, 2-hexyloctyloxy, 4-hexyldecyloxy, 3-hexylundecyloxy, 2-octyldecyloxy, 2-octyldodecyloxy, 3-octyltridecyloxy, 2-decyldodecyloxy, 2-decyltetradecyloxy, 3-decylpentadecanyloxy, 2-dodecylhexadecyloxy, 4-octyltetradecyloxy, 4-decylhexadecyloxy, 4-hexyldecyloxy, 4-octyldodecyloxy, 4-decyltetradecyloxy, 4-dodecylhexadecyloxy;

[0022] Aryl is an aromatic ring system, including phenyl, biphenyl, indanyl, 1-naphthyl, 2-naphthyl and tetrahydronaphthyl; aralkyl or arylalkyl is an alkyl residue attached to the aryl ring;

[0023] Aromatic heteroyl groups include acridine, aziridine, acridine, benzimidazolyl, benzofuranyl, benzothiofuranyl, benzothiophene, benzooxazolyl, benzooxazolinyl, benzothiazolyl, benzotriazolyl, benzotetrazolyl, benzoisooxazolyl, benzoisothiazolyl, benzimidazolinyl, carbazole, 4aH-carbazole, carbolinyl, chromanyl, chromenyl, cenyl, decahydroquinolinyl, 2H,6H-1,5,2-dithiazinyl, dihydrofurano[2,3-b]tetrahydrofuranyl, furanyl, furazanyl, imidazoalkyl, imidazolinyl, imidazolyl, 1H-indazole, imidazopyridyl, pseudoindole, dihydroindole, indazinyl, indoleyl, 3H- Indoleyl, indigo-indoleyl, isobenzofuranyl, isochoryl, isoindazoleyl, isodihydroindoleyl, isoindoleyl, isoquinolinyl, isothiazolyl, isothiazolopyridyl, isoxazolyl, isoxazolopyridyl, methylenedioxyphenyl, morpholinyl, diazanaphthyl, octahydroisoquinolinyl, oxadiazolyl, 1,2,3-oxadiazolyl, 1,2,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,3,4-oxadiazolyl, oxazolylalkyl, oxazolyl, oxazolopyridyl, oxazolyl, naphthalene-intercalated diazaphenyl, hydroxyindoleyl, pyrimidinyl, phenanthidyl, phenanthrololinyl, phenazinyl, phenthiazinyl, phenoxthiazyl, phenoxazinyl, phthalazinyl, piperazineyl, piperidinyl, piperidine Keto, 4-piperidinone, piperin, pteridin, purine, pyran, pyrazin, pyrazolyl, pyrazolinyl, pyrazolopyridyl, pyrazolyl, pyridazinyl, pyridoxazolyl, pyridinium-imidazolyl, pyridothiazolyl, pyridinyl, pyrimidinyl, pyrrolyl, pyrrololinyl, 2-pyrrolidone, 2H-pyrrolyl, pyrrolyl, quinazolinyl, quinolinyl, 4H-quinazinyl, quinoxalinyl, quininecycloyl, tetrazolyl, tetrahydrofuranyl, tetrahydroisoquinolinyl, tetrahydroquinolinyl, 6H-1,2,5-thiadiazinyl, 1,2,3-thiadiazolyl, 1,2,4-thiadiazolyl, 1,2,5-thiadiazolyl, 1,3,4-thiadiazolyl, thiaanthryl, thiazolyl Azolyl, thienyl, thiazopyridyl, thienothiazolyl, thienooxazolyl, thienoimidazolyl, thienyl, triazinyl, 1,2,3-triazolyl, 1,2,4-triazolyl, 1,2,5-triazolyl, 1,3,4-triazolyl and xanthonyl, quinolinyl, isoquinolinyl, phthalazinyl, quinazolinyl, indoleyl, isoindoleyl, dihydroindoleyl, 1H-inzolyl, benzimidazolyl, 1,2,3,4-tetrahydroquinolinyl, 1,2,3,4-tetrahydroisoquinolinyl, 5,6,7,8-tetrahydro-quinolinyl, 2,3-dihydro-benzofuranyl, chromyl, 1,2,3,4-tetrahydro-quinoxalinyl and 1,2,3,4-tetrahydro-quinazolinyl;

[0024] Heteroaryl groups include -phenylbipyridinyl-, -phenylbipyrimidinyl, -pyridylbiphenyl, -pyridylbipyrimidinyl-, and -pyrimidinylbiphenyl-.

[0025] The method for preparing carbazole-based small molecule compounds as described above includes the following steps:

[0026]

[0027] 3,6-Dimethyl-9H-carbazole and NaH were added to a double-necked flask under nitrogen protection, and then anhydrous tetrahydrofuran was injected at 0°C. The solution was stirred at room temperature for 45 minutes. Then, thiophene-2-carbonyl chloride was added to the solution at 0°C, stirred at 0°C for 10 minutes, and stirred further at room temperature for 2 hours. The reaction was then quenched with water. The mixture was extracted with dichloromethane (20 mL × 3), dried, filtered, and evaporated to dryness. The crude residue was purified by silica gel column chromatography (petroleum ether: dichloromethane = 1:1) to obtain a white solid.

[0028] The ratio of 3,6-dimethyl-9H-carbazole:NaH:anhydrous tetrahydrofuran:thiophene-2-carbonyl chloride (mmol:mmol:mL:mmol) was 6.000:18.000:30:7.200.

[0029] The above describes the application of carbazole-based small molecule compounds in the fabrication of organic all-optical synaptic devices.

[0030] An organic all-photosynapse based on a light history-dependent fluorescence intensity mechanism, prepared using the carbazole-based small molecule compound described above, comprises the following steps:

[0031] Weigh out a small molecule compound based on carbazole, dissolve it in dichloromethane, and prepare a 1*10 solution. -5 M solution, also known as a pure photosynaptic device, can measure the luminescence intensity of the solution at 370 nm under different illumination histories, and its 370 nm fluorescence peak has pure photosynaptic characteristics.

[0032] The advantages and positive effects of this invention are as follows:

[0033] 1. This invention is based on the fact that the small organic molecule of carbazole has anti-carbazine dual fluorescence emission, and the fluorescence intensity is related to the light history. It can be applied to the preparation of organic all-optical synaptic devices, realizing neural synaptic behaviors such as light intensity after stimulation, double pulse facilitation, and the transformation of short-range plasticity to long-range plasticity.

[0034] 2. The small molecule of this invention has anti-Kasha dual fluorescence emission characteristics. The first organic all-optical synaptic device prepared based on this type of molecule is difficult to achieve with ordinary organic molecules. Its special photophysical properties enable it to simulate the behavior of multiple neural synapses and achieve good results in artificial all-optical synapses. Attached Figure Description

[0035] Figure 1The ultraviolet-visible absorption spectrum of the organic small molecule provided in Example 1 of this invention;

[0036] Figure 2 The fluorescence emission spectrum of the small organic molecule in dichloromethane solvent under 290 nm wavelength excitation provided in Example 1 of the present invention;

[0037] Figure 3 The fluorescence emission spectra of small organic molecules in dichloromethane solvent at different excitation wavelengths provided in Example 1 of this invention;

[0038] Figure 4 The graph shows the change in fluorescence intensity of the organic small molecule solution at 370 nm as a function of excitation light intensity and time, as provided in Example 1 of the present invention.

[0039] Figure 5 The graph shows the change in fluorescence intensity of the organic small molecule solution at 580 nm as a function of excitation light intensity and time, as provided in Example 1 of the present invention.

[0040] Figure 6 The light intensity-time curves of the organic small molecule solution provided in Example 1 of the present invention under two consecutive ultraviolet light stimuli at 370 nm.

[0041] Figure 7 The light intensity-time curves of the organic small molecule solution provided in Example 1 of the present invention under two consecutive ultraviolet light stimuli at 580 nm.

[0042] Figure 8 The light intensity-time curves of the organic small molecule solution provided in Example 1 of the present invention under ultraviolet light with different stimulation times at 370 nm;

[0043] Figure 9 The image shows the light intensity-time curves of the organic small molecule solution provided in Example 1 of this invention under ultraviolet light at different stimulation frequencies at 370 nm. Detailed Implementation

[0044] The embodiments of the present invention are described in detail below. It should be noted that these embodiments are descriptive and not limiting, and should not be used to limit the scope of protection of the present invention.

[0045] Unless otherwise specified, the raw materials used in this invention are all conventional commercially available products; unless otherwise specified, the methods used in this invention are all conventional methods in the field.

[0046] A small molecule compound based on carbazole, the general structural formula of which is shown in Formula I:

[0047]

[0048] In the structural formula I, R 1 R 2 and R 3 Each independently represents hydrogen, C1-C 30 Alkyl, C1-C 30 alkoxy groups, C6-C 30 Aryl, 5-30 heteroaryl, halogen; n is an integer greater than or equal to 4 and less than 20, and X represents a heteroelement of group VIA.

[0049] Preferably, in structural formula I, R 1 Indicates hydrogen or C1-C 30 Alkyl or halogen, R 2 Indicates hydrogen or C1-C 30 Alkyl or halogen, R 3 X represents hydrogen or halogen, and X represents sulfur.

[0050] Preferably, in structural formula I, R 1 R represents hydrogen or a C1-C6 straight-chain alkyl group or halogen. 2 R represents hydrogen or a C1-C6 straight-chain alkyl group or halogen. 3 X represents hydrogen or chlorine, and X represents sulfur.

[0051] Preferably, the luminescence properties of the small molecule compound are: exhibiting anti-Kasha fluorescence dual emission phenomenon; and the short-wavelength emission peak of the small molecule compound has illumination history-dependent luminescence intensity characteristics.

[0052] Preferably, the general structural formula of the small molecule compound is shown in Formula II:

[0053]

[0054] Preferably, the alkyl group comprises branched and straight-chain saturated aliphatic hydrocarbon groups having a specified number of carbon atoms;

[0055] The alkoxy group is -O-alkyl;

[0056] The aryl group is a monocyclic, bicyclic, or tricyclic ring system having a total of 5 to 12 ring members, wherein at least one ring in the system is aromatic and wherein each ring in the system contains 3 to 7 ring members.

[0057] The heteroaryl group is a stable 3-membered, 4-membered, 5-membered, 6-membered, or 7-membered aromatic monocyclic or aromatic bicyclic or 7-membered, 8-membered, 9-membered, 10-membered, 11-membered, or 12-membered aromatic polycyclic heterocyclic ring, which is completely unsaturated or partially unsaturated, and contains a carbon atom and one, two, three, or four heteroatoms independently selected from N, O, and S; and includes any kind of polycyclic group, wherein any heterocycle is fused with a benzene ring.

[0058] Preferably, C1-C6 alkyl means alkyl having 1 to 6 carbon atoms, including methyl, ethyl, propyl, butyl and pentyl;

[0059] C1-C 30 Alkyl groups refer to alkyl groups with 1 to 30 carbon atoms, including straight-chain or branched alkyl groups. Straight-chain alkyl groups include methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecanyl, n-hexadecyl, n-heptadecyl, and n-octadecyl. Branched alkyl groups include C8-C30 branched alkane groups, including 2-ethylhexyl, 2-ethyloctyl, 2-butylhexyl, 2-hexyloctyl, 4-hexyldecyl, 3-hexylundecyl, 2-octyldecyl, 2-octyldodecyl, 3-octyltridecyl, 2-decyldodecyl, 2-decyltetradecyl, 2-decyltetradecyl, 3-decylpentadecanyl, 2-dodecylhexadecyl, 4-octyltetradecyl, 4-decylhexadecyl, 4-hexyldecyl, 4-octyldodecyl, 4-decyltetradecyl, and 4-dodecylhexadecyl.

[0060] C1-C6 alkoxy groups include C1, C2, C3, C4, C5, and C6 alkoxy groups, including methoxy, ethoxy, propoxy, and tert-butoxy groups; straight-chain alkoxy groups are C1-C6. 12 Alkyl groups include: methoxy, ethoxy, propoxy, n-butoxy, n-pentoxy, n-hexoxy, n-heptoxy, n-octoxy, n-nonoxy, n-decoxy, n-undecyloxy, and n-dodecyloxy; branched alkoxy groups are C8-C. 30 Branched alkoxy groups include: 2-ethylhexyloxy, 2-ethyloctyloxy, 2-butylhexyloxy, 2-hexyloctyloxy, 4-hexyldecyloxy, 3-hexylundecyloxy, 2-octyldecyloxy, 2-octyldodecyloxy, 3-octyltridecyloxy, 2-decyldodecyloxy, 2-decyltetradecyloxy, 3-decylpentadecanyloxy, 2-dodecylhexadecyloxy, 4-octyltetradecyloxy, 4-decylhexadecyloxy, 4-hexyldecyloxy, 4-octyldodecyloxy, 4-decyltetradecyloxy, 4-dodecylhexadecyloxy;

[0061] Aryl is an aromatic ring system, including phenyl, biphenyl, indanyl, 1-naphthyl, 2-naphthyl and tetrahydronaphthyl; aralkyl or arylalkyl is an alkyl residue attached to the aryl ring;

[0062] Aromatic heteroyl groups include acridine, aziridine, acridine, benzimidazolyl, benzofuranyl, benzothiofuranyl, benzothiophene, benzooxazolyl, benzooxazolinyl, benzothiazolyl, benzotriazolyl, benzotetrazolyl, benzoisooxazolyl, benzoisothiazolyl, benzimidazolinyl, carbazole, 4aH-carbazole, carbolinyl, chromanyl, chromenyl, cenyl, decahydroquinolinyl, 2H,6H-1,5,2-dithiazinyl, dihydrofurano[2,3-b]tetrahydrofuranyl, furanyl, furazanyl, imidazoalkyl, imidazolinyl, imidazolyl, 1H-indazole, imidazopyridyl, pseudoindole, dihydroindole, indazinyl, indoleyl, 3H- Indoleyl, indigo-indoleyl, isobenzofuranyl, isochoryl, isoindazoleyl, isodihydroindoleyl, isoindoleyl, isoquinolinyl, isothiazolyl, isothiazolopyridyl, isoxazolyl, isoxazolopyridyl, methylenedioxyphenyl, morpholinyl, diazanaphthyl, octahydroisoquinolinyl, oxadiazolyl, 1,2,3-oxadiazolyl, 1,2,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,3,4-oxadiazolyl, oxazolylalkyl, oxazolyl, oxazolopyridyl, oxazolyl, naphthalene-intercalated diazaphenyl, hydroxyindoleyl, pyrimidinyl, phenanthidyl, phenanthrololinyl, phenazinyl, phenthiazinyl, phenoxthiazyl, phenoxazinyl, phthalazinyl, piperazineyl, piperidinyl, piperidine Keto, 4-piperidinone, piperin, pteridin, purine, pyran, pyrazin, pyrazolyl, pyrazolinyl, pyrazolopyridyl, pyrazolyl, pyridazinyl, pyridoxazolyl, pyridinium-imidazolyl, pyridothiazolyl, pyridinyl, pyrimidinyl, pyrrolyl, pyrrololinyl, 2-pyrrolidone, 2H-pyrrolyl, pyrrolyl, quinazolinyl, quinolinyl, 4H-quinazinyl, quinoxalinyl, quininecycloyl, tetrazolyl, tetrahydrofuranyl, tetrahydroisoquinolinyl, tetrahydroquinolinyl, 6H-1,2,5-thiadiazinyl, 1,2,3-thiadiazolyl, 1,2,4-thiadiazolyl, 1,2,5-thiadiazolyl, 1,3,4-thiadiazolyl, thiaanthryl, thiazolyl Azolyl, thienyl, thiazopyridyl, thienothiazolyl, thienooxazolyl, thienoimidazolyl, thienyl, triazinyl, 1,2,3-triazolyl, 1,2,4-triazolyl, 1,2,5-triazolyl, 1,3,4-triazolyl and xanthonyl, quinolinyl, isoquinolinyl, phthalazinyl, quinazolinyl, indoleyl, isoindoleyl, dihydroindoleyl, 1H-inzolyl, benzimidazolyl, 1,2,3,4-tetrahydroquinolinyl, 1,2,3,4-tetrahydroisoquinolinyl, 5,6,7,8-tetrahydro-quinolinyl, 2,3-dihydro-benzofuranyl, chromyl, 1,2,3,4-tetrahydro-quinoxalinyl and 1,2,3,4-tetrahydro-quinazolinyl;

[0063] Heteroaryl groups include -phenylbipyridinyl-, -phenylbipyrimidinyl, -pyridylbiphenyl, -pyridylbipyrimidinyl-, and -pyrimidinylbiphenyl-.

[0064] The method for preparing carbazole-based small molecule compounds as described above includes the following steps:

[0065]

[0066] 3,6-Dimethyl-9H-carbazole and NaH were added to a double-necked flask under nitrogen protection, and then anhydrous tetrahydrofuran was injected at 0°C. The solution was stirred at room temperature for 45 minutes. Then, thiophene-2-carbonyl chloride was added to the solution at 0°C, stirred at 0°C for 10 minutes, and stirred further at room temperature for 2 hours. The reaction was then quenched with water. The mixture was extracted with dichloromethane (20 mL × 3), dried, filtered, and evaporated to dryness. The crude residue was purified by silica gel column chromatography (petroleum ether: dichloromethane = 1:1) to obtain a white solid.

[0067] The ratio of 3,6-dimethyl-9H-carbazole:NaH:anhydrous tetrahydrofuran:thiophene-2-carbonyl chloride (mmol:mmol:mL:mmol) was 6.000:18.000:30:7.200.

[0068] The above describes the application of carbazole-based small molecule compounds in the fabrication of organic all-optical synaptic devices.

[0069] An organic all-photosynapse based on a light history-dependent fluorescence intensity mechanism, prepared using the carbazole-based small molecule compound described above, comprises the following steps:

[0070] Weigh out a small molecule compound based on carbazole, dissolve it in dichloromethane, and prepare a 1*10 solution. -5 M solution, also known as a pure photosynaptic device, can measure the luminescence intensity of the solution at 370 nm under different illumination histories, and its 370 nm fluorescence peak has pure photosynaptic characteristics.

[0071] Specifically, the relevant preparation and detection examples are as follows:

[0072] Example 1

[0073] A small molecule compound based on carbazole, the general structural formula of which is shown in formula (Ⅰ);

[0074]

[0075] In structural formula I, R 1 R 2 and R 3 Each independently represents hydrogen, C1-C 30 Alkyl, C1-C 30 alkoxy groups, C6-C 30Aryl, 5-30 heteroaryl, halogen; n is an integer greater than or equal to 4 and less than 20, and X represents the heteroelement oxygen, sulfur, selenium, and tellurium of group VIA.

[0076] Preferably, in the structure of formula I, R 1 Indicates hydrogen or C1-C 30 Alkyl or halogen, R 2 Indicates hydrogen or C1-C 30 Alkyl or halogen, R 3 X represents hydrogen or halogen;

[0077] Preferably, R 1 R represents hydrogen or a C1-C6 straight-chain alkyl group or halogen. 2 R represents hydrogen or a C1-C6 straight-chain alkyl group or halogen. 3 X represents hydrogen or chlorine, and X represents sulfur.

[0078] The term "alkyl" as used in this invention is intended to include branched and straight-chain saturated aliphatic hydrocarbon groups having a specified number of carbon atoms. For example, "C1-C6 alkyl" refers to an alkyl group having 1 to 6 carbon atoms. Examples of alkyl groups include, but are not limited to, methyl (Me), ethyl (Et), propyl (e.g., n-propyl and isopropyl), butyl (e.g., n-butyl, isobutyl, tert-butyl), and pentyl (e.g., n-pentyl, isopentyl, neopentyl). Again, for example, C1-C... 30 Alkyl groups refer to alkyl groups with 1 to 30 carbon atoms, including straight-chain or branched alkyl groups. Straight-chain alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecanyl, n-hexadecyl, n-heptadecyl, and n-octadecyl. Branched alkyl groups include, but are not limited to, C8-C30 branched alkane groups, including: 2-ethylhexyl, 2-ethyloctyl, 2-butylhexyl, 2-hexyloctyl, 4-hexyldecyl, 3-hexylundecyl, 2-octyldecyl, 2-octyldodecyl, 3-octyltridecyl, 2-decyldodecyl, 2-decyltetradecyl, 2-decyltetradecyl, 3-decylpentadecanyl, 2-dodecylhexadecyl, 4-octyltetradecyl, 4-decylhexadecyl, 4-hexyldecyl, 4-octyldodecyl, 4-decyltetradecyl, and 4-dodecylhexadecyl.

[0079] The term "alkoxy" refers to an -O-alkyl group. For example, "C1-C6 alkoxy" is intended to include C1, C2, C3, C4, C5, and C6 alkoxy groups. Examples of alkoxy groups include, but are not limited to, methoxy, ethoxy, propoxy (e.g., n-propoxy and isopropoxy), and tert-butoxy. For example, straight-chain alkoxy groups can be C1-C6. 12The alkoxy groups include, but are not limited to: methoxy, ethoxy, propoxy, n-butoxy, n-pentoxy, n-hexoxy, n-heptoxy, n-octoxy, n-nonoxy, n-decoxy, n-undecoxy, and n-dodecoxy; branched alkoxy groups can be C8-C. 30 Branched alkoxy groups, including but not limited to: 2-ethylhexyloxy, 2-ethyloctyloxy, 2-butylhexyloxy, 2-hexyloctyloxy, 4-hexyldecyloxy, 3-hexylundecyloxy, 2-octyldecyloxy, 2-octyldodecyloxy, 3-octyltridecyloxy, 2-decyldodecyloxy, 2-decyltetradecyloxy, 3-decylpentadecanyloxy, 2-dodecylhexadecyloxy, 4-octyltetradecyloxy, 4-decylhexadecyloxy, 4-hexyldecyloxy, 4-octyldodecyloxy, 4-decyltetradecyloxy, 4-dodecylhexadecyloxy;

[0080] The term "aryl," alone or as part of a larger group such as "aralkyl," "aralkyloxy," or "aryloxyalkyl," refers to a monocyclic, bicyclic, or tricyclic ring system having a total of 5 to 12 ring members, wherein at least one ring in the system is aromatic and each ring in the system contains 3 to 7 ring members. In some embodiments of the invention, "aryl" refers to an aromatic ring system, including but not limited to phenyl, biphenyl, indanyl, 1-naphthyl, 2-naphthyl, and tetrahydronaphthyl. The term "aralkyl" or "arylalkyl" refers to an alkyl residue attached to an aryl ring. Non-limiting examples include benzyl, phenethyl, etc. Fused aryl groups can be attached to another group at a suitable position on a cycloalkyl ring or an aromatic ring. Example: Dashed lines drawn from a ring system indicate that the bond can be attached to any suitable ring atom.

[0081] The term "heteroaryl" refers to a stable 3-, 4-, 5-, 6-, or 7-membered aromatic monocyclic or bicyclic, or 7-, 8-, 9-, 10-, 11-, or 12-membered aromatic polycyclic heterocycle that is fully unsaturated or partially unsaturated and contains a carbon atom and one, two, three, or four heteroatoms independently selected from N, O, and S; and includes any of the following polycyclic groups, wherein any heterocycle defined above is fused to a benzene ring. The nitrogen and sulfur heteroatoms may optionally be oxidized. The nitrogen atom may be substituted or unsubstituted (i.e., N or NR, where R is H or, if defined, another substituent). The heterocycle may be attached to its side group at any heteroatom or carbon atom to obtain a stable structure. If the resulting compound is stable, the heterocyclic group described herein may be substituted at a carbon or nitrogen atom. The nitrogen in the heterocycle may optionally be quaternized. Preferably, when the total number of S and O atoms in the heterocycle exceeds 1, these heteroatoms are not adjacent to each other. Preferably, the total number of S and O atoms in the heterocycle is not greater than 1. When the term "heterocycle" is used, it is intended to include heteroaryl groups.Examples of aromatic heteroyl groups include, but are not limited to, acridine, aziridine, acridine, benzimidazolyl, benzofuranyl, benzothiofuranyl, benzothiophene, benzooxazolyl, benzooxazolinyl, benzothiazolyl, benzotriazolyl, benzotetrazolyl, benzoisooxazolyl, benzoisothiazolyl, benzimidazolinyl, carbazole, 4aH-carbazole, carbolinyl, chromanyl, chromenyl, cenyl, decahydroquinolinyl, 2H,6H-1,5,2-diathiazinyl, dihydrofurano[2,3-b]tetrahydrofuranyl, furanyl, furazanyl, imidazoalkyl, imidazolinyl, imidazolyl, 1H-indazole, imidazopyridyl, indolenyl, and dihydroindolenyl. Indazinyl, indolyl, 3H-indolyl, isatinoyl, isobenzofuranyl, isochoryl, isoindazoleyl, isodihydroindolyl, isoindolyl, isoquinolinyl, isothiazolyl, isothiazolopyridyl, isoxazolyl, isoxazolopyridyl, methylenedioxyphenyl, morpholinyl, diazanaphthyl, octahydroisoquinolinyl, oxadiazolyl, 1,2,3-oxadiazolyl, 1,2,4-oxadiazolyl, 1,2,5-oxadiazolyl, 1,3,4-oxadiazolyl, oxazolylalkyl, oxazolyl, oxazolopyridyl, naphthalene-intercalated diazaphenyl, hydroxyindolyl, pyrimidinyl, phenanthidyl, phenanthrololinyl, phenazinyl, phenothiazinyl, phenothiazinyl, phenothiazinyl Phthalasinyl, Piperazinyl, Piperidinyl, Piperidinoneyl, 4-Piperidinoneyl, Piperinyl, Pteridinyl, Puryl, Pyranyl, Pyrazinyl, Pyrazoloalkyl, Pyrazolinyl, Pyrazolopyridyl, Pyrazolyl, Pyridazinyl, Pyridoxazolyl, Pyridoimidazolyl, Pyridothiazolyl, Pyridinyl, Pyrimidinyl, Pyrrolylyl, Pyrrololinyl, 2-Pyrrolidoneyl, 2H-Pyrrolyl, Pyrrolyl, Quinazolinyl, Quinolinyl, 4H-Quinazinyl, Quinoxalinyl, Quinoxalinyl, Quininecycloyl, Tetrazolyl, Tetrahydrofuranyl, Tetrahydroisoquinolinyl, Tetrahydroquinolinyl, 6H-1,2,5-Thiadiazinyl, 1,2,3-Thiadiazinyl, 1,2,4-Thiadiazinyl, 1,2,5-Thiadiazinyl, 1,3,4-Thiadiazinyl Thianyl, thiazolyl, thiazolyl, thiazolyl, thiazolyl-pyridyl, thiazolyl-thiazolyl, thiazolyl-oxazolyl, thiazolyl-imidazolyl, thiazolyl, triazinyl, 1,2,3-triazolyl, 1,2,4-triazolyl, 1,2,5-triazolyl, 1,3,4-triazolyl and xanthonyl, quinolinyl, isoquinolinyl, phthalazinyl, quinazolinyl, indoleyl, isoindoleyl, dihydroindoleyl, 1H-inzolyl, benzimidazolyl, 1,2,3,4-tetrahydroquinolinyl, 1,2,3,4-tetrahydroisoquinolinyl, 5,6,7,8-tetrahydro-quinolinyl, 2,3-dihydro-benzofuranyl, chromyl, 1,2,3,4-tetrahydro-quinoxalinyl and 1,2,3,4-tetrahydro-quinazolinyl.The term "heteroaryl" may also include biaryl structures formed by an "aryl" as defined above and a monocyclic "heteroaryl", such as, but not limited to, "-phenylbipyridinyl-", "-phenylbipyrimidinyl", "-pyridylbiphenyl", "-pyridylbipyrimidinyl-", and "-pyrimidinylbiphenyl-"; wherein the present invention also includes fused-ring and spirocyclic compounds containing, for example, the heterocycles described above.

[0082] In this disclosure, the designation Cx1-Cx2 is used when referring to substituent groups, indicating that the number of carbon atoms in the substituent group can be x1 to x2. For example, C1-C30 indicates that the group contains 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30 carbon atoms.

[0083] In this disclosure, when referring to cyclic groups (e.g., aryl, heteroaryl), the expression "x1-x2 membered ring" is used, indicating that the number of ring atoms in the group can be x1 to x2. For example, the 5-30 membered cyclic group can be a 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30 membered ring. The ring atom can be a carbon atom or a heteroatom, for example, a heteroatom selected from N, O, and S. When the ring is a heterocycle, the heterocycle can contain 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or more cyclic heteroatoms, for example, heteroatoms selected from N, O, and S.

[0084] Preferably, the chemical formula of a small molecule compound based on carbazole is as shown in formula (II):

[0085]

[0086] The compound in Formula II is denoted as S2OC.

[0087] Example 2

[0088] A method for preparing the above-mentioned carbazole-based small molecule compound includes the following steps:

[0089]

[0090] 3,6-Dimethyl-9H-carbazole (1.170 g, 6.000 mmol) and NaH (0.430 g, 18.000 mmol) were added to a two-necked flask under nitrogen protection, followed by the injection of anhydrous tetrahydrofuran (THF, 30 mL) at 0 °C. The solution was stirred at room temperature for 45 minutes. Thiophene-2-carbonyl chloride (1.052 g, 7.200 mmol) was then added to the solution at 0 °C, stirred for 10 minutes, and further stirred at room temperature for 2 hours. The reaction was then quenched with water. The mixture was extracted with dichloromethane (20 mL × 3), dried, filtered, and evaporated to dryness. The crude residue was purified by silica gel column chromatography (petroleum ether: dichloromethane = 1:1) to give a white solid, S2OC.

[0091] The structural characterization data of compound S2OC are as follows:

[0092] 1 HNMR (400MHz, CDCl3) δ (ppm): 7.77 (s, 2H), 7.71 (s, 1H), 7.56 (s, 3H), 7.17 (s, 2H), 7.12 (s, 1H), 2.50 (s, 6H);

[0093] 13 C NMR (100MHz, CDCl3) δ (ppm): 162.70, 137.97, 137.59, 133.41, 133.00, 132.71, 127.77, 127.61, 126.09, 119.95, 115.21, 21.45;

[0094] HRMS(ESI)m / z for C 19 H 16 NOS + (M + H) + Cal.:306.0947; Found:306.0937

[0095] The UV-Vis absorption spectrum of S2OC molecules in dichloromethane solution is as follows: Figure 1 As shown. Figure 2 The emission spectrum of the S2OC solution under excitation at a wavelength of 290 nm is shown, with two emission peaks at 370 nm and 580 nm. Emission spectra at different excitation wavelengths are shown below. Figure 3 As shown, when the excitation wavelength is greater than 420 nm, only the emission peak at 580 nm can be detected, indicating that the molecule has wavelength-dependent emission spectral characteristics, exhibiting fluorescence with anti-Kassa dual emission.

[0096] Example 3

[0097] In this embodiment, carbazole-based small molecules are used in the preparation of pure photosynaptic devices. The preparation method includes:

[0098] Weigh 5 mg of the molecule S2OC obtained in Example 1, dissolve it in dichloromethane, and prepare 1*10 -5 The M solution, a pure photosynaptic device, can measure the luminescence intensity of the solution at 370 nm under different ultraviolet light irradiation histories.

[0099] Figure 4 and Figure 5 The fluorescence intensity at 370 nm and 580 nm varies with excitation light intensity and time, respectively. It can be seen that as the excitation light intensity increases and the excitation time increases, the fluorescence intensity at 370 nm also increases continuously, while the fluorescence intensity at 580 nm does not change with the light history. It can be seen that the fluorescence intensity at 370 nm can show the synaptic behavior curve, while that at 580 nm cannot.

[0100] Figure 6 and Figure 7 The figures show the fluorescence intensity-time curves of the S2OC solution at 370 nm and 580 nm after two consecutive UV light stimulations. It can be seen that after the second excitation, the light intensity at 370 nm is greater than that after the first excitation. This is the double-pulse facilitation behavior of the neural synapse, a manifestation of short-range plasticity. However, the light intensity at 580 nm remains unchanged between the first and second pulses, which is not a synaptic behavior. Most organic molecules exhibit fluorescence properties similar to that at 580 nm, with the luminescence intensity not changing with the duration of light exposure. This type of carbazole-based small molecule is the first organic molecule to possess purely photosynaptic properties, based on its unique photophysical processes.

[0101] Figure 8 and Figure 9 The image shows the intensity-time curves at the 370 nm fluorescence peak for the S2OC solution under different UV stimulation cycles (1, 2, 5, 10) and UV stimulation frequencies (2 Hz, 1 Hz, 0.5 Hz). It can be seen that the final light intensity varies under different UV stimulation cycles and frequencies, exhibiting the cycle and frequency dependence characteristics of pure photosynapses. The transition from short-range plasticity to long-range plasticity is achieved by adjusting the stimulation cycles and frequencies. These findings indicate that the device possesses the characteristics of an artificial synapse and can be used in fields such as associative learning, memory imaging, and machine learning.

[0102] Although embodiments of the invention have been disclosed for illustrative purposes, those skilled in the art will understand that various substitutions, variations, and modifications are possible without departing from the spirit and scope of the invention and the appended claims. Therefore, the scope of the invention is not limited to the contents disclosed in the embodiments.

Claims

1. Application of carbazole-based small molecule compounds in the fabrication of organic all-optical synaptic devices; The general structural formula of the carbazole-based small molecule compound is shown in Formula II:

2. An organic all-photosynapse based on a light history-dependent fluorescence intensity mechanism, prepared using a carbazole-based small molecule compound, characterized in that: The preparation method includes the following steps: Weigh out a small molecule compound based on carbazole, dissolve it in dichloromethane, and prepare a 1*10 solution. -5 M solution refers to a pure photosynaptic device; The general structural formula of the carbazole-based small molecule compound is shown in Formula II:

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