CN111205855B - Preparation of Highly Stable Organic Fluorescent Sensing Materials and Their Application in Explosive Detection - Google Patents

Abstract

An organic fluorescent sensing material, which is formed by co-assembly of a carbazole derivative represented by formula (A) and a fluorene derivative represented by formula (I). The organic fluorescent sensing material can overcome the problems of poor detection sensitivity when the compound of formula (A) is used alone and poor stability when the compound of formula (I) is used alone. Specifically, the present invention can effectively combine the advantages of different molecules by using co-assembly, and the anti-oxidative molecule (the compound represented by formula (I)) and the molecule with excellent detection performance (the compound represented by formula (A)) are co-assembled. The material can solve the problem of material stability well, and at the same time maintain high sensitivity detection of explosives.

Description

Preparation of Highly Stable Organic Fluorescent Sensing Materials and Their Application in Explosive Detection

technical field

The invention relates to an organic fluorescent sensing material, in particular to a P-type semiconductor material based on carbazole molecules and fluorene molecules, a preparation method thereof and an application in detecting explosives.

Background technique

The monitoring of explosives is an important issue related to the health of our people, sustainable economic development and national security. Explosives are mainly divided into the following categories: nitroalkanes (DMNB), nitroaromatic compounds (DNT, TNT), nitroamines (RDX), nitroesters (PETN), black powder (S), oxides (TATP), etc. Fluorescence detection has become a hot research topic due to its unique advantages of high sensitivity and high selectivity. Currently, six types of explosives can be detected with high sensitivity by fluorescence methods. However, the existing reported explosive detection materials based on the fluorescence detection method generally have the defects of easy oxidation and poor stability, which are not conducive to repeated use in practical applications. If other groups are introduced, the detection sensitivity of the material may be affected. Therefore, it is particularly difficult to use as little material as possible to achieve the goal of detecting explosives and maintaining the stability of the material using simple analysis.

SUMMARY OF THE INVENTION

In order to solve the above technical problems, the present invention provides an organic fluorescent sensing material, which is formed by co-assembly of a carbazole derivative represented by formula (A) and a fluorene derivative represented by formula (I),

In the formula (A) and formula (I),

R is the same or different and independently selected from C _1-12 straight or branched chain alkyl, -(CH ₂ ) _x -R ¹ -OR ² , -(CH ₂ ) _y -R ¹ -R ³ , - (CH ₂ ) _z -R ⁴ , -COOR ⁵ , wherein x is 0, 1 or 2, y is 0, 1 or 2, z is an integer of 1-8, and R ¹ is arylene, heteroarylene , halogenated arylene or halogenated heteroarylene, R ² is C _1-10 straight or branched chain alkyl, R ³ is -H, -CHF ₂ , -CF ₃ , unsubstituted, or optionally The following groups substituted by one, two or more CHF ₂ or CF ₃ : C _1-10 straight or branched chain alkyl, C _3-10 cycloalkyl, C _3-10 heterocycloalkane base; R ⁴ is -CHF ₂ , -CF ₃ , R ⁵ is C _1-6 alkyl; R ⁵ is C _1-6 alkyl;

R' is the same or different, and is independently selected from -(CH ₂ ) _x' -R ⁶ -R ⁷ , wherein x' is 0, 1 or 2, and R ⁶ is arylene, heteroarylene, halogenated Arylene or halogenated heteroarylene, R ⁷ is H, -COOC _1-10 alkyl, C _2-10 alkynyl, -CN, C _1-10 alkyl, C _2-10 alkenyl , -COR ⁹ ;

R" is selected from O or S;

m is selected from the integer of 3-40;

n is an integer of 1-10.

Preferably, the organic fluorescent sensing material of the present invention is formed by co-assembly of the carbazole derivative represented by formula (A) and the fluorene derivative represented by formula (I) through π-π interaction.

According to the present invention, in the co-assembly process, the molar ratio of the two compounds can be adjusted arbitrarily, preferably 1:1-1:100.

Preferably, in the formula (A) and formula (I), R' is the same or different, and is independently selected from -(CH ₂ ) _x' -R ⁶ -R ⁷ , x' is 0 or 1; R ⁶ Arylene, halogenated arylene, such as phenylene, naphthylene, halogenated phenylene, halogenated naphthylene; R ⁷ is H, -COOC _1-3 alkyl, C _2-6 alkynyl or -CN;

Also preferably, in the formula (A) and formula (I), R' is the same or different, and is independently selected from at least one of the following groups:

处为连接位点。in,

is the attachment site.

Preferably, in the formula (A) and formula (I), R is selected from C _3-10 straight or branched chain alkyl, (CH ₂ ) _x -R ¹ -OR ² , -(CH ₂ ) _y -R ¹ -R ³ or -(CH ₂ ) _z -R ⁴ , wherein x is 0, 1 or 2, y is 0, 1 or 2, z is an integer of 2-6, R ¹ is phenylene, Naphthylene, halogenated phenylene, R ² is C _1-10 linear or branched alkyl, R ³ is -H, -CF ₃ , C _1-10 linear or branched alkyl, or C _1-10 straight or branched chain alkyl substituted with one CF ₃ , R ⁴ is -CF ₃ .

Also preferably, R is selected from one of the following groups:

处为连接位点。Among the above groups,

is the attachment site.

According to the present invention, the organic fluorescent sensing material is an organic semiconductor nanowire obtained by co-assembly of a carbazole derivative represented by formula (A) and a fluorene derivative represented by formula (I) through π-π interaction or nanoribbons.

Further, the organic semiconductor fluorescent sensing material is a porous membrane with a network structure formed by co-assembly and weaving of the organic semiconductor nanowires.

The present invention also provides the above-mentioned preparation method of the organic fluorescent sensing material, and the method comprises the following steps:

(1) Preparation of a carbazole derivative represented by the following formula (A),

(2) preparing a fluorene derivative represented by the following formula (I),

wherein each substituent in formula (A) and formula (I) is as previously defined;

(3) placing the carbazole derivative represented by the formula (A) obtained in the step (1) and the fluorene derivative represented by the formula (I) obtained in the step (2) in a good solvent and a poor solvent, and by co-assembling the The organic semiconductor fluorescent sensing material is obtained in the following way; the molar ratio of formula (A) and formula (I) used in co-assembly can be adjusted arbitrarily, preferably (1:1-100:1);

The good solvent is selected from at least one of halogenated alkane solvents and ester solvents; the poor solvent is selected from at least one of alcohol solvents and naphthenic solvents.

According to the present invention, in step (1):

For the preparation method of the carbazole derivative represented by formula (A), reference can be made to the method described in Patent Document 2017109673710;

According to the present invention, in step (2):

When preparing the fluorene derivative of formula (I) with n=1, the step (2) specifically includes:

(1a) The compound represented by formula (II) is reacted with RX' to obtain the compound represented by formula (III);

X in formula (II) is the same or different and is independently selected from halogen (eg Br, I); X' in RX' is selected from halogen (eg Br, I); R in formula (III) and RX' The definition is the same as formula (I);

(1b) The compound represented by formula (III) is reacted with R'B(OH) ₂ to obtain the compound represented by formula (IV);

In formula (IV) and R'B(OH) ₂ , the definitions of R' are the same as those of formula (I); in formula (IV), the definitions of R and X are the same as those of formula (III);

(1c) The compound represented by formula (V) reacts with divaleryl diboron to obtain the compound represented by formula (VI);

In formula (VI), the definition of R is the same as formula (I);

(1d) The compound represented by the formula (IV) reacts with the compound represented by the formula (VI) to obtain the fluorene derivative represented by the formula (I), wherein n=1; wherein, the compound represented by the formula (IV) and the compound represented by the formula (VI) The molar ratio of the indicated compounds is 2.1:1 to 2.5:1 (for example, 2.2:1);

When 1<n≤10 in formula (I), the step (1) specifically includes:

(1a') The compound represented by the formula (II') is reacted with RX' to obtain the compound represented by the formula (III');

X's in formula (II') are the same or different and are independently selected from halogen (eg Br, I); X' in RX' is selected from halogen (eg Br, I); in formula (III') and RX' The definition of R is the same as formula (I); n' is an integer of 1-10;

(1c') The compound represented by the formula (III') reacts with divaleryl diboron to obtain the compound represented by the formula (V');

(1d') The compound represented by formula (V') is reacted with R'X to obtain the fluorene derivative represented by formula (I); wherein, the molar ratio of R'X to the compound represented by formula (V') is 2.1:1 ~2.5:1 (eg 2.2:1).

In the above step (1a) or (1a'), the reaction is carried out in a solvent. The solvent is an organic solvent that can dissolve the raw material, such as an amide compound, which can be selected from N,N-dimethylformamide.

In the above step (1a) or (1a'), the reaction is carried out at a temperature of -10 to 10°C, preferably -5 to 5°C.

In the above step (1a), the reaction is carried out under the action of a catalyst. The catalyst is, for example, sodium hydride. The equivalent ratio of the compound represented by the formula (II) to the catalyst is 1:1 to 1:3.

In the above step (1a'), the reaction is carried out under the action of a catalyst. The catalyst is, for example, sodium hydride. The equivalent ratio of the compound represented by the formula (II') to the catalyst is 1:(n'+0.1) to 1:(n'+0.5).

In the above step (1a), the equivalent ratio of the compound of formula (II) to RX' is 1.2-1:2.

In the above step (1a'), the equivalent ratio of the compound of formula (II') to RX' is 1:(n'+0.2)～1:(n'+0.5).

In a preferred technical solution, to prepare a fluorene derivative with n=1 in formula (I), the step (1a) is specifically: dissolving 1 equivalent of 2,7-dibromocarbazole in N,N-dibromocarbazole Methyl-formamide was configured into a solution with a concentration of 1g/30ml, the above solution was placed in an ice bath at 0°C, and 1.2 equivalents of sodium hydride solid were slowly added. After stirring for half an hour, 1.5 equivalents of 1-bromo was added slowly. Octane, 2-bromobutane, 4-trifluoromethylbenzyl bromide, benzyl bromide or 4-methoxybenzyl bromide were reacted at room temperature overnight, and the product was obtained by column chromatography.

In the above step (1b), the reaction is carried out in a solvent. The solvent is an organic solvent that can dissolve the raw material, such as an ether solvent, specifically 1,4-dioxane.

In the above step (1b), the equivalent ratio of the compound of formula (III) to R'B(OH) ₂ is 1:(1-3).

In the above step (1b), the reaction is carried out in a catalyst system, and the catalyst system includes tetrakis(triphenylphosphine)palladium and cesium carbonate. The addition amount of tetrakis(triphenylphosphine)palladium is 5-15% equivalent, and the addition amount of cesium carbonate is 1-4 equivalents relative to 1 equivalent of the compound of formula (III).

In the above step (1b), the reaction is carried out under the protection of an inert gas, the reaction temperature is 70-90° C., and the reaction time is 6-8 hours.

In a preferred embodiment, the step (1b) is specifically: (1b) taking 1 equivalent of the product obtained in step (1a), dissolving it in 1,4-dioxane to prepare a concentration of 1g/20ml The solution was added with 1 equivalent of p-methoxycarbonylbenzeneboronic acid, 10% equivalent of tetrakis(triphenylphosphine) palladium, and 3 equivalents of cesium carbonate under the protection of argon at 80 ° C. After 6 hours of reaction, it was obtained by column chromatography. product.

In the above step (1c) or (1c'), the reaction is carried out in a solvent. The solvent is an organic solvent that can dissolve the raw material, such as an ether solvent, specifically 1,4-dioxane.

In the above step (1c) or (1c'), the equivalent ratio of the compound of formula (V) or formula (III') to divaleryl diboron is 1:4-6.

In the above step (1c) or (1c'), the reaction is carried out in a catalyst system comprising potassium acetate and [1,1'-bis(diphenylphosphino)ferrocene]dichloride palladium. With respect to 1 equivalent of the compound of formula (V) and formula (III'), the addition amount of potassium acetate is 10 to 20 equivalents, and the amount of [1,1'-bis(diphenylphosphino)ferrocene]dichloride palladium is 10 to 20 equivalents. The addition amount is 5 to 15% equivalent.

In the above step (1c) or (1c'), the reaction is carried out under the protection of an inert gas, the reaction temperature is 70-80°C, and the reaction time is 4-8 hours.

In a preferred embodiment, to prepare a carbazole derivative with n=3 in formula (I), the step (1c) is specifically: taking 1 equivalent of the product obtained in step (1a), adding 1,4-di The oxane was prepared into a solution with a concentration of 1g/20ml, and 5 equivalents of divaleryl diboron, 14 equivalents of potassium acetate, and 10% equivalents of [1,1'-bis(diphenylphosphino)diocene] were added. Iron]palladium dichloride was reacted for 6 hours at 80°C under the protection of argon, and the product was obtained by column chromatography.

In the above step (1d) or (1d'), the reaction is carried out in a solvent. The solvent is an organic solvent that can dissolve the raw material, such as aromatic hydrocarbons, specifically benzene or toluene.

In the above step (1d) or (1d'), the equivalent ratio of the compound of the formula (IV) to the compound of the formula (VI) or the compound of the formula (V') to R'X is 1:(1-3).

In the above step (1d) or (1d'), the reaction is carried out in a catalyst system comprising tetrakis(triphenylphosphine)palladium and potassium carbonate. The amount of potassium carbonate added is 3 to 5 equivalents, and the amount of tetrakis(triphenylphosphine)palladium added is 5 to 15% equivalent to 1 equivalent of the compound of formula (V) or compound (V').

In the above step (1d) or (1d'), the reaction is carried out under the protection of an inert gas, the reaction temperature is 70-90°C, and the reaction time is 12-48 hours.

In a preferred embodiment, to prepare a fluorene derivative with n=2 in formula (I), the step (1d) is specifically: taking 1 mmol and 2.2 mmol of the products obtained in step (1c) and step (1b), respectively, It was added to 20 ml of toluene solution, 10% tetrakis (triphenylphosphine) palladium and 3 equivalents of potassium carbonate were added under the protection of argon at 80° C. After overnight reaction, the product was obtained by column chromatography.

Preferably, the step (3) comprises: dissolving the carbazole derivative represented by the formula (A) obtained in the step (1) and the fluorene derivative represented by the formula (I) obtained in the step (2) in a good solution In the solvent, a poor solvent is added, shaken, and then allowed to stand to obtain the suspension of the organic fluorescent sensing material;

Preferably, the step (3) further includes: after the suspension of the organic fluorescent sensing material is allowed to stand, take out the organic fluorescent sensing material located at the bottom of the preparation container, place it in a poor solvent again, shake well and disperse and Repeated washing to obtain the organic fluorescent sensing material;

Preferably, the volume ratio (ml:ml) of the good solvent to the poor solvent is 1:2 to 1:20, preferably 1:2 to 1:15;

Preferably, the good solvent is selected from at least one of chlorinated alkane solvents and ester solvents, such as dichloromethane, chloroform, 1,2-dichloroethane, 1,1,2,2- At least one of tetrachloroethane, methyl acetate, ethyl acetate or butyl acetate;

Preferably, the poor solvent is selected from at least one of alcohol organic solvents or cycloalkane, for example, at least one of methanol, ethanol or cyclohexane.

The present invention also provides the application of the above-mentioned organic fluorescent sensing material in detecting explosives.

The present invention also provides the above-mentioned method for detecting an explosive by an organic fluorescent sensing material, comprising: contacting the organic fluorescent sensing material with the vapor of an explosive, and when the fluorescence of the organic fluorescent sensing material changes, there is an explosion. thing.

In the present invention, the explosives are selected from black powder (RDX), trinitrotoluene (TNT), dinitrotoluene (DNT), pentaerythritol tetranitrate (PETN), ammonium nitrate (AN) and black powder at least one of (S).

Beneficial effects of the present invention:

1) The organic fluorescent sensing material of the present invention is a typical P-type semiconductor fluorescent sensing material. The organic fluorescent sensing material can overcome the problems of poor detection sensitivity when the compound of formula (A) is used alone and poor stability when the compound of formula (I) is used alone. Specifically, in the present invention, the advantages of different molecules can be effectively combined by co-assembly, and the anti-oxidative molecules (the compound represented by formula (I)) and the molecules with excellent detection performance (the compound represented by formula (A)) are co-assembled. The material can solve the problem of material stability well, and at the same time maintain high sensitivity detection of explosives.

resonance energy transfer,简称“FRET”)，式(A)所示化合物可以向式(I)所示化合物传递能量，使式(I)所示化合物发出荧光，抑制了与氧的光反应，增强了材料的稳定性；而当材料表面与爆炸物接触时，式(A)所示化合物的激子快速向爆炸物迁移，FRET的作用减弱，引起荧光淬灭，从而可以对爆炸物进行荧光检测。因此，将式(A)所示咔唑衍生物和式(I)所示芴衍生物共组装形成的有机半导体荧光传感材料可以实现在提高材料的稳定性的情况下，保持对爆炸物检测的高灵敏度检测。As shown in FIG. 18, in the material of the present invention, when the absorption spectrum of the compound represented by the formula (I) and the emission spectrum of the compound represented by the formula (A) overlap, due to the fluorescence resonance energy transfer (

resonance energy transfer, referred to as "FRET"), the compound represented by the formula (A) can transfer energy to the compound represented by the formula (I), so that the compound represented by the formula (I) emits fluorescence, inhibits the photoreaction with oxygen, and enhances the The stability of the material; and when the surface of the material is in contact with the explosive, the excitons of the compound represented by formula (A) rapidly migrate to the explosive, and the effect of FRET is weakened, causing fluorescence quenching, so that the explosive can be detected by fluorescence. Therefore, the organic semiconductor fluorescent sensing material formed by the co-assembly of the carbazole derivative represented by the formula (A) and the fluorene derivative represented by the formula (I) can realize the detection of explosives while improving the stability of the material. high-sensitivity detection.

2) The organic fluorescent sensing material of the present invention has a large specific surface area, and has the characteristics of many surface pores, which is conducive to the adsorption and diffusion of the detected explosive vapor on the surface of the nanowire or nanobelt to better interact with the explosive. Perform high-sensitivity detection. For example, it can be used for the detection of trace amounts of explosives such as ng or sub-ng levels.

3) The present invention also provides a method for preparing the organic semiconductor fluorescent sensing material. The synthesis route of the method is simple and efficient, which is convenient for large-scale preparation, and the growth method of nanowires or nanobelts is simple and fast.

Definition and Explanation of Terms

Unless otherwise indicated, the numerical ranges recited in this specification and claims are equivalent to at least reciting each specific integer value therein. For example, the numerical range "1-10" is equivalent to reciting each integer value in the numerical range "1-10", ie, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10. It is to be understood that in the context of one, two or more used herein in describing a substituent, "more" shall refer to an integer > 3, such as 3, 4, 5, 6, 7, 8, 9 or 10 .

The term "halo" refers to fluoro, chloro, bromo and iodo substitution.

The term "C _1-12 straight-chain or branched-chain alkyl" is to be understood as preferably denoting a straight-chain or branched saturated hydrocarbon group having 1 to 12 carbon atoms, preferably a C _1-10 alkyl group. "C _1-10 alkyl" is understood to mean preferably a straight-chain or branched saturated hydrocarbon radical having 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 carbon atoms. The alkyl group is, for example, methyl, ethyl, propyl, butyl, pentyl, hexyl, isopropyl, isobutyl, sec-butyl, tert-butyl, isopentyl. In particular, the group has 1, 2, 3, 4, 5, 6 carbon atoms ("C _1-6 alkyl"), eg methyl, ethyl, propyl, butyl, pentyl, hexyl , isopropyl, isobutyl, sec-butyl, tert-butyl.

The term "C _1-10 straight-chain or branched-chain alkyl" is to be understood as preferably denoting straight-chain or branched saturated hydrocarbon radicals having 1 to 10 carbon atoms, such as methyl, ethyl, propyl, butyl, pentyl base, hexyl, isopropyl, isobutyl, sec-butyl, tert-butyl, isopentyl.

The term "cycloalkyl" should be understood to mean a saturated monocyclic, bicyclic hydrocarbon ring or bridged ring having 3 to 20 carbon atoms, preferably a " _C3-10 cycloalkyl". The term "C _3-10 cycloalkyl" is understood to mean a saturated monocyclic or bicyclic hydrocarbon ring having 3, 4, 5, 6, 7, 8, 9 or 10 carbon atoms. The C _3-10 cycloalkyl group can be a monocyclic hydrocarbon group, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl or cyclodecyl, or a bicyclic Hydrocarbyl such as decalin ring.

The term "heterocyclyl" means a saturated monocyclic or bicyclic hydrocarbon ring containing 1-5 heteroatoms independently selected from N, O and S, preferably "3-10 membered heterocyclyl". The term "3-10 heterocyclyl" means a saturated monocyclic or bicyclic hydrocarbon ring containing 1-5, preferably 1-3 heteroatoms selected from N, O and S. The heterocyclyl group can be attached to the remainder of the molecule through any two of the carbon atoms or a nitrogen atom, if present. In particular, the heterocyclic group may include, but is not limited to: 4-membered ring, such as azetidinyl, oxetanyl; 5-membered ring, such as tetrahydrofuranyl, dioxolyl, pyrrole Alkyl, imidazolidinyl, pyrazolidinyl, pyrrolinyl; or 6-membered ring, such as tetrahydropyranyl, piperidinyl, morpholinyl, dithianyl, thiomorpholinyl, piperazinyl or trithianyl; or a 7-membered ring such as diazepanyl. Optionally, the heterocyclyl group can be benzo-fused. The heterocyclyl group may be bicyclic, such as, but not limited to, a 5,5 membered ring, such as a hexahydrocyclopento[c]pyrrole-2(1H)-yl ring, or a 5,6 membered bicyclic ring, such as a hexahydropyrrole The [1,2-a]pyrazin-2(1H)-yl ring. The nitrogen-containing ring may be partially unsaturated, i.e. it may contain one or more double bonds such as, but not limited to, 2,5-dihydro-1H-pyrrolyl, 4H-[1,3,4]thiadiene oxazinyl, 4,5-dihydrooxazolyl, or 4H-[1,4]thiazinyl, alternatively, it may be benzo-fused, such as, but not limited to, dihydroisoquinolinyl. According to the present invention, the heterocyclic group is non-aromatic.

The term "arylene" is understood to preferably mean an aromatic or partially aromatic monocyclic, bicyclic or tricyclic hydrocarbon ring having 6 to 20 carbon atoms, preferably a " _{C6-14 arylidene} ". The term "C _{6-14 arylidene} " is to be understood as preferably denoting an aromatic or partially aromatic monocyclic, bicyclic or tricyclic having 6, 7, 8, 9, 10, 11, 12, 13 or 14 carbon atoms Cyclic hydrocarbon rings ("C _6-14 aryl"), especially rings having 6 carbon atoms ("C ₆ -arylene"), such as phenylene; or biphenylene, or those having 9 carbons A ring of atoms ("C ₉ arylene"), such as indanylene or indenylene, or a ring of 10 carbon atoms ("C ₁₀ arylene"), such as tetrahydronaphthylene, Dihydronaphthyl or naphthylene, or a ring of 13 carbon atoms ("C _{13 arylidene"), such as fluorenylene, or a ring of 14 carbon atoms ("C 14 arylene} ") ), such as anthracenylene.

The term "heteroarylene" is understood to include monocyclic, bicyclic or tricyclic aromatic ring systems having 5-20 ring atoms and containing 1-5 heteroatoms independently selected from N, O and S , for example "5-14 membered heteroarylene". The term "5-14 membered heteroarylene" is understood to include monocyclic, bicyclic or tricyclic aromatic ring systems having 5, 6, 7, 8, 9, 10, 11, 12, 13 or 14 ring atoms, especially 5 or 6 or 9 or 10 carbon atoms, and it contains 1 to 5, preferably 1 to 3, heteroatoms each independently selected from N, O and S. And, additionally in each case may be benzo-fused. In particular, the heteroaryl group is selected from thienylene, furanylene, pyrrolylene, oxazolylylene, thiazolylylene, imidazolylide, pyrazolylylene, isoxazolylylene, isothiazolylylene, Oxadiazolyl, triazolylidene, thiadiazolylidene, thiadiazolylidene, etc. and their benzo derivatives, etc.

Wherein, the terms "aryl" and "heteroaryl" refer to the case where the substituent at one end of the above-mentioned "arylene" and "heteroarylene" structure is H.

Description of drawings

Figure 1. The nuclear magnetic data spectrum of compound 1 of Example 1 of the present invention.

Figure 2. A graph of the mass spectrum data of Compound 1 of Example 1 of the present invention.

Figure 3. The nuclear magnetic data spectrum of compound 2 of Example 1 of the present invention.

Figure 4. A graph of mass spectrometry data of Compound 2 of Example 1 of the present invention.

Figure 5. Absorption and fluorescence spectra of Compound 1 and Compound 2 of the present invention.

Figure 6. The photostability test chart of the fluorescent sensing material obtained by co-assembly of compound 1 and compound 2 of the present invention and the fluorescent sensing material self-assembled from compound 1.

Figure 7. The photostability test chart of the fluorescent sensing material obtained by the co-assembly of compound 3 and compound 4 of the present invention.

Figure 8. SEM image of the organic semiconductor nanowires formed by the co-assembly of compound 1 and compound 2 of the present invention.

FIG. 9 is a graph showing the detection fluorescence of TNT by the organic semiconductor nanowires prepared in Example 1 of the present invention.

FIG. 10 is a graph showing the detection fluorescence of DNT by the organic semiconductor nanowires prepared in Example 1 of the present invention.

FIG. 11 is a graph showing the fluorescence detection of S by the organic semiconductor nanowires prepared in Example 1 of the present invention.

FIG. 12 is a graph of the detection fluorescence of the organic semiconductor nanowires prepared in Example 1 of the present invention for RDX.

Fig. 13 is a graph showing the detection fluorescence of PETN by the organic semiconductor nanowires prepared in Example 1 of the present invention.

FIG. 14 is a graph showing the detection fluorescence of AN by the organic semiconductor nanowires prepared in Example 1 of the present invention.

FIG. 15 is a graph showing the detection fluorescence of TNT by the organic semiconductor nanowires prepared in Example 2 of the present invention.

FIG. 16 is a graph showing the fluorescence detection of S by the organic semiconductor nanowires prepared in Example 2 of the present invention.

FIG. 17 is a graph of the detection fluorescence of the organic semiconductor nanowires prepared in Example 2 of the present invention for RDX.

18 is a schematic diagram of the mechanism of the organic semiconductor nanomaterial of the present invention for detecting explosives.

Detailed ways

The technical solutions of the present invention will be described in further detail below with reference to specific embodiments. It should be understood that the following examples are only for illustrating and explaining the present invention, and should not be construed as limiting the protection scope of the present invention. All technologies implemented based on the above content of the present invention are covered within the intended protection scope of the present invention.

The experimental methods used in the following examples are conventional methods unless otherwise specified; the reagents, materials, etc. used in the following examples can be obtained from commercial sources unless otherwise specified.

Example 1

Compound 1 and compound were prepared, and the preparation method was as follows:

(1) Dissolve 1 g of 2,7-dibromocarbazole in 30 mL of N,N-dimethylformamide (DMF) solution, place the above solution in an ice bath at 0°C, and slowly add 1.2 equivalents 74 mg of solid sodium hydride, and after stirring continuously for half an hour, 1.5 equivalents of 1-bromooctane were slowly added, and after reacting at room temperature overnight, the product was obtained by column chromatography.

(2) Take 500 mg of the product obtained in step (1), add 20 ml of 1,4-dioxane solution, add 5 equivalents of divaleryl diboron, 14 equivalents of potassium acetate, 10% equivalents of [1,1 '-bis(diphenylphosphino)ferrocene]palladium dichloride was reacted for 6 hours at 80°C under the protection of argon, and the product (TM-1) was obtained by column chromatography.

(3) Take 500 mg of the product obtained in step (1), add 20 ml of 1,4-dioxane solution, add 1 equivalent of p-methylcarbonyl benzene boronic acid, 10% equivalent of tetrakis(triphenylphosphine) palladium, The product (TM-2) was obtained by column chromatography after reacting 3 equivalents of cesium carbonate under the protection of argon at 80°C for 6 hours.

(4) respectively take the product 1mmol and 2.2mmol obtained in step (2) and step (3), add in 20ml toluene solution, add 10% tetrakis (triphenylphosphine) palladium, 3 equivalents of potassium carbonate at 80 ° C Under the protection of argon, after overnight reaction, the product (compound 1) was obtained by column chromatography; its nuclear magnetic resonance data map is shown in Figure 1;

(5) 500 mg of 2,7-dibromofluorenone was added to 20 ml of 1,4-dioxane solution, 5 equivalents of divaleryl diboron, 14 equivalents of potassium acetate, 10% equivalents of [1, 1'-Bis(diphenylphosphino)ferrocene]palladium dichloride was reacted for 6 hours at 80°C under the protection of argon, and the product (TM-3) was obtained by column chromatography.

(6) respectively take the product 1mmol and 2.2mmol obtained in step (3) and step (5), add in 20ml toluene solution, add 10% tetrakis (triphenylphosphine) palladium, 3 equivalents of potassium carbonate at 80 ° C Under the protection of argon, after overnight reaction, the product (compound 2) was obtained by column chromatography; its nuclear magnetic resonance data diagram is shown in FIG. 3 ; and the mass spectrum data diagram is shown in FIG. 4 .

(7) The compounds obtained in steps (4) and (6) are dissolved in a good solvent, and then a poor solvent is added, and the good solvent is ethyl acetate (replace ethyl acetate with dichloromethane, chloroform, 1,2 -Any one of dichloroethane or 1,1,2,2-tetrachloroethane can achieve the same experimental effect), and the poor solvent is methanol (replace methanol with any of ethanol or cyclohexane One can achieve the same experimental effect), the volume ratio of the good solvent and the poor solvent is 1:7 (or the volume of the two is 1:(5-10) any ratio can also achieve the same experimental effect). After standing, the carbazole derivative with p-methylcarbonylbenzene and the fluorenone derivative can obtain a suspension of organic semiconductor nanowires with high stability and fluorescence response to several types of explosives through co-assembly.

The organic semiconductor fluorescent sensing materials obtained by the co-assembly of carbazole derivatives (compound 1) and fluorene derivatives (compound 2) with p-methylcarbonyl phenyl and the organic fluorescent materials self-assembled from compound 1 were respectively carried out. Light Stability Test. By analyzing the fluorescence intensity change graph in Figure 6, it is found that the fluorescence intensity of the self-assembled fluorescent sensing material obtained by compound 1 decreased by 80% after continuous illumination for 1 hour, while the organic fluorescent sensing material co-assembled by the two molecules was continuously illuminated for 1 hour. After 1 hour of illumination, the fluorescence intensity only decreased by 40%, indicating that the anti-oxidation ability of the material was improved after the co-assembly of the fluorene derivative, and the stability of the organic semiconductor fluorescent sensing material was greatly improved.

Example 2

To prepare compound 3 and compound 4, the preparation method is as follows:

(1) Dissolve 1 g of 2,7-dibromocarbazole in 30 mL of N,N-dimethylformamide (DMF) solution, place the above solution in an ice bath at 0°C, and slowly add 1.2 equivalents 74 mg of solid sodium hydride, and after stirring continuously for half an hour, 1.5 equivalents of 1-bromooctane were slowly added, and after reacting at room temperature overnight, the product was obtained by column chromatography.

(2) Take 500 mg of the product obtained in step (1), add 20 ml of 1,4-dioxane solution, add 5 equivalents of divaleryl diboron, 14 equivalents of potassium acetate, 10% equivalents of [1,1 '-bis(diphenylphosphino)ferrocene]palladium dichloride was reacted for 6 hours at 80°C under the protection of argon, and the product (TM-1) was obtained by column chromatography.

(3) Take 500 mg of the product obtained in step (1), add 20 ml of 1,4-dioxane solution, add 1 equivalent of p-cyanophenylboronic acid, 10% equivalent of tetrakis(triphenylphosphine) palladium, 3 The product (TM-4) was obtained by column chromatography after reacting an equivalent of cesium carbonate at 80°C under the protection of argon for 6 hours.

(4) respectively take the product 1mmol and 2.2mmol obtained in step (2) and step (3), add in 20ml toluene solution, add 10% tetrakis (triphenylphosphine) palladium, 3 equivalents of potassium carbonate at 80 ° C Under argon protection, after overnight reaction, a carbazole derivative (compound 3) of formula (A) in which R is a straight-chain octyl group, R' is 4-cyanophenyl, and n is 3 is obtained by column chromatography.

(5) 500 mg of 2,7-dibromofluorenone was added to 20 ml of 1,4-dioxane solution, 5 equivalents of divaleryl diboron, 14 equivalents of potassium acetate, 10% equivalents of [1, 1'-Bis(diphenylphosphino)ferrocene]palladium dichloride was reacted for 6 hours at 80°C under the protection of argon, and the product (TM-3) was obtained by column chromatography.

(6) respectively take the product 1mmol and 2.2mmol obtained in step (3) and step (5), add in 20ml toluene solution, add 10% tetrakis (triphenylphosphine) palladium, 3 equivalents of potassium carbonate at 80 ° C Under the protection of argon, after overnight reaction, the product compound 4 was obtained by column chromatography.

(7) Dissolve the carbazole derivative (compound 3) with n is 3 and the fluorene derivative (compound 4) with n is 1 obtained in steps (4) and (6) in In the good solvent, add a poor solvent, and the good solvent is ethyl acetate (replace ethyl acetate with dichloromethane, chloroform, 1,2-dichloroethane or 1,1,2,2-tetrachloroethane) Any one of the alkanes can achieve the same experimental effect), the poor solvent is methanol (replace methanol with either ethanol or cyclohexane to achieve the same experimental effect), the volume of the good solvent and the poor solvent The ratio is 14 (or the same experimental effect can be achieved in any ratio in which the two volumes are 1:(2-8)); standing, the carbazole derivative with 4-cyanophenyl group is self-assembled Suspensions of organic semiconductor nanowires with different fluorescence responses to several classes of explosives were obtained.

The organic semiconductor fluorescent sensing materials obtained by the co-assembly of compound 3 and compound 4 were respectively tested for photostability. By analyzing the change of fluorescence intensity in Figure 7, it is found that the fluorescence intensity of the organic semiconductor fluorescent sensing material assembled by compound 3 decreased by 75.7% after continuous illumination for 1 hour, while the organic fluorescent sensing material co-assembled by the two compounds was at After 1 hour of continuous illumination, the fluorescence intensity only decreased by 18%, indicating that the anti-oxidation ability of the material was improved after the co-assembly of the fluorene derivative, and the stability of the organic semiconductor fluorescent sensing material was greatly improved.

Example 3

The suspension in step (7) of Example 1 was taken out with a pipette from the sample at the bottom of the container and placed on a clean silicon wafer surface. After the poor solvent was evaporated cleanly, it was placed in an ion sputtering machine (Leica), After the vacuum was evacuated to a vacuum of 10 ^-4 Pa, metal platinum particles were sputtered on the surface for 120 s. The silicon wafer was taken out and placed in a scanning electron microscope (Hitachi S8010) to observe its morphology. As shown in a, b, c and d in Figure 8, it can be observed that the material prepared in Example 1 is a unique mesh-like porous structure formed by the assembly and weaving of one-dimensional organic semiconductor nanowires, which provides a fluorescence response for the detection of explosives Signal.

Example 4

After the suspension obtained in step (7) of Example 1 was allowed to stand for 24 hours, the film at the bottom of the container was taken out and coated in a quartz glass tube to prepare a fluorescent sensing material. The porous membrane coated in the quartz glass tube was excited using a 380 nm excitation light source. Using a solid explosive detector, pipette 0.5ng, 1ng, and 2ng of TNT into the heating gun respectively, and set the heating temperature to 170°C. Blow different concentrations of TNT steam on the surface of the porous membrane to detect As a result, fluorescence changes as shown in Figure 9 occurred at the three concentrations.

Example 5

The same method as in Example 4 was used, except that the test substance was replaced with 2ng, 5ng, and 10ng of DNT, and the detection results showed the fluorescence changes as shown in Figure 10 at the three concentrations.

Example 6

The same method as in Example 4 was adopted, except that the test substance was replaced with 0.5ng, 1ng, and 2ng S (black powder), and the detection result showed the fluorescence change as shown in Figure 11 at the three concentrations.

Example 7

Using the same method as in Example 4, the test substance was replaced with 0.5ng, 1ng, and 2ng of RDX, and the detection results showed the fluorescence changes as shown in Figure 12 at the three concentrations.

Example 8

Using the same method as in Example 4, the test substance was replaced with 0.5ng, 1ng, and 2ng PETN, and the detection results showed the fluorescence changes as shown in Figure 13 at the three concentrations.

Example 9

Using the same method as in Example 4, the test substance was changed to 2ng, 4ng, and 8ng of AN, and the detection results showed the fluorescence changes as shown in Figure 14 at the three concentrations.

Example 10

After the suspension obtained in step (7) of Example 2 was allowed to stand for 24 hours, the film at the bottom of the container was taken out and coated in a quartz glass tube to prepare a fluorescent sensing material. The porous membrane coated in the quartz glass tube was excited using a 380 nm excitation light source. Using a solid explosive detector, pipette 0.5ng, 1ng, and 2ng of TNT into the heating gun respectively, and set the heating temperature to 170°C. Blow different concentrations of TNT steam on the surface of the porous membrane to detect As a result, fluorescence changes as shown in Figure 15 occurred at the three concentrations.

Example 11

The same method as in Example 10 was adopted, except that the test substance was replaced with 0.5ng, 1ng, and 2ng of S, and the detection results showed the fluorescence changes as shown in Figure 16 at the three concentrations.

Example 12

Using the same method as in Example 10, the test substance was changed to 0.5ng, 1ng, and 2ng RDX, and the detection results showed the fluorescence changes as shown in Figure 17 at the three concentrations.

Example 13

(1) Dissolve 1 g of 2,7-dibromocarbazole with a degree of polymerization of 2 in 30 mL of N,N-dimethylformamide (DMF) solution, and place the above solution in an ice bath at 0°C , slowly add 1.2 equivalents of 74 mg of solid sodium hydride, continue stirring for half an hour, slowly add 1.5 equivalents of 1-bromohexane, react overnight at room temperature, and obtain the product by column chromatography.

(2) Take 500 mg of the product obtained in step (1), add 20 ml of 1,4-dioxane solution, add 5 equivalents of divaleryl diboron, 14 equivalents of potassium acetate, 10% equivalents of [1,1 '-bis(diphenylphosphino)ferrocene]palladium dichloride was reacted for 6 hours at 80°C under the protection of argon, and the product (TM-5) was obtained by column chromatography.

(3) Take 500 mg of the product obtained in step (1), add 20 ml of 1,4-dioxane solution, add 1 equivalent of 3,5-ditrifluoromethylbenzeneboronic acid, 10% equivalent of tetrakis(triphenylene) phosphine) palladium and 3 equivalents of cesium carbonate under the protection of argon at 80°C, after 6 hours of reaction, the product (TM-6) was obtained by column chromatography.

(4) respectively take the product 1mmol and 2.2mmol obtained in step (2) and step (3), add in 20ml toluene solution, add 10% tetrakis (triphenylphosphine) palladium, 3 equivalents of potassium carbonate at 80 ° C Under the protection of argon, after overnight reaction, compound 5 was obtained by column chromatography.

(5) 500 mg of 2,7-dibromofluorenone was added to 20 ml of 1,4-dioxane solution, 5 equivalents of divaleryl diboron, 14 equivalents of potassium acetate, 10% equivalents of [1, 1'-Bis(diphenylphosphino)ferrocene]palladium dichloride was reacted for 6 hours at 80°C under the protection of argon, and the product was obtained by column chromatography.

(6) Dissolve 1 g of 2,7-dibromocarbazole in 30 mL of N,N-dimethylformamide (DMF) solution, place the above solution in an ice bath at 0°C, and slowly add 1.2 equivalents of 74 mg of solid sodium hydride, after continuous stirring for half an hour, 1.5 equivalents of 1-bromohexane were slowly added, and after overnight reaction at room temperature, the product was obtained by column chromatography.

(7) Take 500 mg of the product obtained in step (6), add 20 ml of 1,4-dioxane solution, add 5 equivalents of divaleryl diboron, 14 equivalents of potassium acetate, 10% equivalents of [1,1 '-Bis(diphenylphosphino)ferrocene]palladium dichloride was reacted for 6 hours at 80°C under the protection of argon, and the product (TM-6) was obtained by column chromatography.

(8) respectively take 1 mmol and 2.2 mmol of the product obtained in step (5) and step (7), add to 20 ml of toluene solution, add 10% tetrakis (triphenylphosphine) palladium, 3 equivalents of potassium carbonate at 80 ° C Under the protection of argon, after overnight reaction, compound 6 was obtained by column chromatography.

(9) Compound 5 and compound 6 obtained in steps (4) and (8) are dissolved in a good solvent, and then a poor solvent is added, and the good solvent is ethyl acetate (replace ethyl acetate with dichloromethane, chloroform , 1,2-dichloroethane or any one of 1,1,2,2-tetrachloroethane can achieve the same experimental effect), the poor solvent is methanol (replace methanol with ethanol or cyclohexane Any one of the alkanes can achieve the same experimental effect), the volume ratio of the good solvent to the poor solvent is 1:15 (or the volume of the two is 1:(10~20) any ratio can also achieve the same experimental effect) standing, the carbazole derivative with 3,5-ditrifluoromethylphenyl group and the fluorene derivative obtain a suspension of organic semiconductor nanowires with fluorescence response to explosives through co-assembly.

It is determined that the sensing material obtained by the above co-assembly has the same stability as the sensing material in Example 1, and has similar response changes to several types of explosives, which has high stability and can be used for explosives. The role of highly sensitive fluorescence detection.

The embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (14)

1. An organic fluorescent sensing material, characterized in that it is formed by co-assembly of a carbazole derivative shown in formula (A) and a fluorene derivative shown in formula (I),

In the formula (A) and formula (I), R is the same or different and independently selected from C _1-12 straight or branched chain alkyl, -(CH ₂ ) _x -R ¹ -OR ² , -(CH ₂ ) _y -R ¹ -R ³ , - (CH ₂ ) _z -R ⁴ , -COOR ⁵ , wherein x is 0, 1 or 2, y is 0, 1 or 2, z is an integer of 1-8, and R ¹ is arylene, heteroarylene , halogenated arylene or halogenated heteroarylene, R ² is C _1-10 straight or branched chain alkyl, R ³ is -H, -CHF ₂ , -CF ₃ , unsubstituted, or optionally The following groups substituted by one, two or more CHF ₂ or CF ₃ : C _1-10 straight or branched chain alkyl, C _3-10 cycloalkyl, C _3-10 heterocycloalkane base; R ⁴ is -CHF ₂ , -CF ₃ , R ⁵ is C _1-6 alkyl; R' is the same or different, and is independently selected from -(CH ₂ ) _x' -R ⁶ -R ⁷ , wherein x' is 0, 1 or 2, and R ⁶ is arylene, heteroarylene, halogenated Arylene or halogenated heteroarylene, R ⁷ is H, -COOC _1-10 alkyl, C _2-10 alkynyl, -CN, C _1-10 alkyl, C _2-10 alkenyl ; R" is selected from O or S; m is selected from the integer of 3-40; n is an integer of 1-10. 2 . The organic fluorescent sensing material according to claim 1 , wherein the organic fluorescent sensing material is composed of a carbazole derivative represented by formula (A) and a fluorene derivative represented by formula (I). 3 . Formed by co-assembly through π-π interactions. 3 . The organic fluorescent sensing material according to claim 1 , wherein in the co-assembly process, the molar ratio of the two compounds can be adjusted arbitrarily. 4 . 4 . The organic fluorescent sensing material according to claim 1 , wherein in the co-assembly process, the molar ratio of the two compounds is 1:1-1:100. 5 . 5. The organic fluorescent sensing material according to claim 1 or 2, wherein, in the formula (A) and the formula (I), R' is the same or different, and is independently selected from -(CH ₂ ) _x' -R ⁶ -R ⁷ , x' is 0 or 1; R ⁶ is arylene, halogenated arylene; R ⁷ is H, -COOC _1-3 alkyl, C _2-6 alkynyl or -CN. 6 . The organic fluorescent sensing material according to claim 5 , wherein the R ⁶ is a phenylene group, a naphthylene group, a halogenated phenylene group, or a halogenated naphthylene group. 7 . 7. The organic fluorescent sensing material according to any one of claims 1-3, characterized in that, in the formula (A) and formula (I), R is selected from linear or branched chains of C _3-10 Alkyl, (CH ₂ ) _x -R ¹ -OR ² , -(CH ₂ ) _y -R ¹ -R ³ or -(CH ₂ ) _z -R ⁴ , wherein x is 0, 1 or 2 and y is 0, 1 or 2, z is an integer of 2-6, R ¹ is phenylene, naphthylene, halogenated phenylene, R ² is C _1-10 straight or branched chain alkyl, R ³ is -H, -CF ₃ , C _1-10 linear or branched alkyl, or C _1-10 linear or branched alkyl substituted with one CF ₃ , R ⁴ is -CF ₃ . 8. The organic fluorescent sensing material according to any one of claims 1-3, wherein, in the formula (A) and formula (I), R' is the same or different, and is independently selected from the following groups: At least one of the regiments:

R is selected from one of the following groups:

Among the above groups,

is the attachment site. 9. The organic fluorescent sensing material according to any one of claims 1-3, wherein the organic fluorescent sensing material is composed of a carbazole derivative represented by formula (A) and formula (I) Organic semiconductor nanowires or nanoribbons obtained by co-assembly of fluorene derivatives through π-π interactions are shown. 10 . The organic fluorescent sensing material according to claim 9 , wherein the organic fluorescent sensing material is a porous membrane with a network structure formed by weaving the organic semiconductor nanowires. 11 . 11. The method for preparing an organic fluorescent sensing material according to any one of claims 1-10, wherein the method comprises the following steps: (1) Preparation of a carbazole derivative represented by the following formula (A),

(2) preparing a fluorene derivative represented by the following formula (I),

(3) placing the carbazole derivative represented by the formula (A) obtained in the step (1) and the fluorene derivative represented by the formula (I) obtained in the step (2) in a good solvent and a poor solvent, and by co-assembling the The organic semiconductor fluorescent sensing material is obtained in the following way; the molar ratio of formula (A) and formula (I) used in co-assembly can be adjusted arbitrarily; The good solvent is selected from at least one of halogenated alkane solvents and ester solvents; the poor solvent is selected from at least one of alcohol solvents and naphthenic solvents. 12. Application of the organic fluorescent sensing material according to any one of claims 1-10 in detecting explosives. 13. The method for detecting explosives by an organic fluorescent sensing material according to any one of claims 1 to 10, wherein the method comprises: contacting the organic fluorescent sensing material with the vapor of the explosive, and when the organic fluorescent Explosives are present when the fluorescence of the sensitive material changes. 14. The method for detecting explosives according to claim 13, wherein the explosives are selected from RDX (RDX), trinitrotoluene (TNT), dinitrotoluene (DNT), pentaerythritol tetrakis At least one of nitrate (PETN), ammonium nitrate (AN) and black powder (S).

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