CN114957080A - 1,2, 3-triaryl substituted indole with rigid structure for enhancing aggregation-induced fluorescence property - Google Patents

Abstract

The invention discloses a 1,2, 3-triaryl substituted indole ring with rigid structure fluorescence function, which is prepared by the following steps: the preparation method is characterized in that indole rings are used as a construction framework, palladium acetate is used as a catalyst, and the synthesis is carried out by a one-pot method, and the steps are as follows: s01, putting 450uL of halogenated aromatic hydrocarbon, 728uL of aniline, 712mg of tolane, 90mg of palladium acetate and 672mg of sodium bicarbonate into a round-bottom flask, uniformly mixing, and then adding 40mLDMF (sodium dodecyl benzene sulfonate) to obtain a mixed solution; s02, reacting the mixed solution in an oil bath kettle at 110 ℃ for 18h, cooling, filtering through a short silica gel plug, and removing the solvent by spinning to obtain a crude mixture; s03, purifying by column chromatography to obtain white solid with the mass of 186mg, the yield of 50% and the fluorescence excitation wavelength of 310 nm. The 1,2, 3-triaryl substituted indole ring with the rigid structure fluorescence function realizes fluorescence enhancement through adjustment of molecular composition, structure and accumulation mode in an aggregation state, and overcomes the defects of the traditional optical functional material in the aspect.

Description

1,2, 3-triaryl substituted indole with rigid structure for enhancing aggregation-induced fluorescence property

Technical Field

The invention belongs to the technical field of organic synthetic chemistry, and particularly relates to 1,2, 3-triaryl substituted indole with a rigid structure for enhancing aggregation-induced fluorescence.

Background

In 2001, the Tang Benze task group discovered that molecular aggregation can convert 1-methyl-1, 2,3,4, 5-penta-phenyl silole from a weak luminescent molecule to a very strong luminescent species, which is contrary to the conventional phenomenon of aggregation quenching luminescence. In more than ten years later, the aggregation-induced fluorescent material attracts people's extensive attention and research, and has good application prospects in the fields of organic light-emitting diodes, biosensing and imaging, fluorescent dyes, chemical sensing, biological probes and the like;

fluorescence generally occurs in molecules of a pi-electron conjugated system having a rigid structure and a planar structure, and as the degree of conjugation and the degree of molecular planarity increase, the fluorescence efficiency increases and the fluorescence spectrum shifts to a long-wavelength direction. Indoles are a large group of very important molecules that have the following characteristics that produce fluorescence: (1) having a large conjugated system; (2) a rigid planar structure.

These luminescent materials generally have a helical non-coplanar structure, which can effectively prevent pi-pi accumulation between molecules, thereby avoiding non-radiative energy loss. In the traditional organic optical functional material, fluorescence is usually weakened or quenched in an aggregation state, so that the practical application of the organic optical functional material is restricted, and on the other hand, the conjugated performance of most aggregation-induced luminescent compounds is reduced due to a non-coplanar spiral structure.

Disclosure of Invention

The present invention aims at providing a 1,2, 3-triaryl-substituted indole with a rigid structure to enhance the fluorescence property induced by aggregation, so as to solve the technical problems mentioned in the last paragraph of the background art.

To achieve the above object, the present invention provides a method for synthesizing indoles having a large conjugated system. Under the influence of the large rigid conjugated structure, the rigid indole ring shows strong AIE luminescence property, and fluorescence spectra are shifted by introducing different rigid structures, and the fluorescence intensities of the rigid indole ring are also different.

The rigid indole compound is 1,2, 3-triphenyl-1H-indole with a general formula (I):

a rigid structure enhanced aggregation-induced fluorescence property 1,2, 3-triaryl substituted indole is synthesized by a one-pot method by using an indole ring as a construction skeleton and palladium acetate as a catalyst, and comprises the following steps:

s01, uniformly mixing halogenated aromatic hydrocarbon, aniline, diphenylacetylene, palladium acetate and sodium bicarbonate, and then adding super-dry DMF (dimethyl formamide) to obtain a mixed solution;

s02, reacting the mixed solution at 110 ℃ for 18 hours, cooling, filtering through a short silica gel plug, and removing the solvent by spinning to obtain a crude mixture;

s03, purifying by column chromatography (n-hexane/ethyl acetate) to obtain the 1,2, 3-triaryl substituted indole.

The rigid structure enhances the technical effects and advantages of the 1,2, 3-triaryl substituted indole with aggregation-induced fluorescence property:

1. fluorescence of the traditional organic optical functional material is usually weakened or quenched in an aggregation state, so that the practical application of the organic photoelectric functional material is restricted, the indole has aggregation-induced emission property, and fluorescence enhancement is realized by adjusting molecular composition, structure and accumulation mode in the aggregation state, so that the defects of the traditional optical functional material in the aspect are overcome;

2. the 1,2, 3-triaryl substituted indole not only contains a large amount of ten-electron aromatic conjugated indole rings, but also the triaryl at the 1,2, 3-position meets the requirement of a propeller-shaped non-planar structure, and can be obtained by cycloaddition of three components of halogen aromatic hydrocarbon, alkyne and aniline which are catalyzed by palladium, the prepared rigid indole ring shows strong liquid and solid fluorescence, and has high AIE luminous performance, and the novel AIE molecule containing the rigid structure has great advantage in the aspect of luminescence;

3. by comparing fluorescence spectra, the synthesized rigid indole ring without substituent has strongest fluorescence and good luminescence property; compared with the pentaphenyl pyrrole, the rigid indole ring has larger rigidity and conjugated structure, the fluorescence curve in the fluorescence spectrum generates obvious red shift, and the fluorescence intensity is enhanced; in the fluorescence measured by the 1,2, 3-triaryl substituted indole with the substituent, the substituent is the strongest fluorescence property of the rigid indole ring for electron donating because the electron donating group can greatly reduce the energy gap between HOMO and LUMO so that the absorption and emission spectra of molecules are red-shifted, and meanwhile, the distorted molecular configuration also ensures the AIE performance of the molecules. Among different substituents, the methoxy-containing substituted 1,2, 3-triaryl substituted indole ring compound has the best aggregation fluorescence effect.

Drawings

FIG. 1 is a nuclear magnetic hydrogen spectrum of the product of example 1;

FIG. 2 is a nuclear magnetic hydrogen spectrum of the product of example 2;

FIG. 3 is a nuclear magnetic hydrogen spectrum of the product of example 3;

FIG. 4 is a nuclear magnetic hydrogen spectrum of the product of example 4;

FIG. 5 is a comparison of the fluorescence intensity of the products of examples 1,2,3,4 and pentaphenylpyrrole.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.

Example 1

A1, 2, 3-triaryl substituted indole ring with rigid structure fluorescence function has a chemical structural formula as follows:

the preparation method comprises the following steps: indole ring is used as a construction framework, palladium acetate is used as a catalyst, and the synthesis is carried out by a one-pot method, wherein the reaction flow is as follows:

the method comprises the following steps:

s01, putting 450uL of halogenated aromatic hydrocarbon, 728uL of aniline, 712mg of tolane, 90mg of palladium acetate and 672mg of sodium bicarbonate into a round-bottom flask, uniformly mixing, and then adding 40mLDMF (sodium dodecyl benzene sulfonate) to obtain a mixed solution;

s02, reacting the mixed solution in an oil bath kettle at 110 ℃ for 18h, cooling, filtering through a short silica gel plug, and removing the solvent by spinning to obtain a crude mixture;

s03, purifying by column chromatography (n-hexane/ethyl acetate, 99: 1) to obtain the product as white solid with the mass of 186mg, the yield of 50% and the fluorescence excitation wavelength of 310 nm.

Example 2

A1, 2, 3-triaryl substituted indole ring with rigid structure fluorescence function has a chemical structural formula as follows:

the preparation method comprises the following steps: indole ring is used as a construction framework, palladium acetate is used as a catalyst, and the synthesis is carried out by a one-pot method, wherein the reaction flow is as follows:

the method comprises the following steps:

s01, putting 450uL of halogenated aromatic hydrocarbon, 902uL of o-methoxyaniline, 712mg of tolane, 90mg of palladium acetate and 672mg of sodium bicarbonate into a round-bottom flask, uniformly mixing, and then adding 40mLDMF to obtain a mixed solution

S02, the mixture is put into an oil bath at 110 ℃ for 18h, cooled and filtered through a short plug of silica gel. Removing the solvent by rotary evaporation to obtain a crude mixture

S03, purifying by column chromatography (n-hexane/ethyl acetate, 98: 2), the product is grey solid with the mass of 492mg, the yield is 60%, and the fluorescence excitation wavelength is 310 nm.

Example 3

A1, 2, 3-triaryl substituted indole ring with rigid structure fluorescence function has a chemical structural formula as follows:

the preparation method comprises the following steps: indole ring is used as a construction framework, palladium acetate is used as a catalyst, and the synthesis is carried out by a one-pot method, wherein the reaction flow is as follows:

the method comprises the following steps:

s01, putting 450uL halogenated aromatic hydrocarbon, 1.2890g of parachlorocarboaniline, 712mg of tolane, 90mg of palladium acetate and 672mg of sodium bicarbonate into a round-bottom flask, uniformly mixing, and then adding 40mLDMF (sodium dodecyl benzene sulfonate) to obtain a mixed solution;

s02, reacting the mixed solution in an oil bath kettle at 110 ℃ for 18h, cooling, filtering through a short silica gel plug, and removing the solvent by spinning to obtain a crude mixture;

s03, purifying by column chromatography (n-hexane/ethyl acetate, 98: 2) to obtain a white solid product with the mass of 0.2230g, the yield of 25% and the fluorescence excitation wavelength of 310 nm.

Example 4

A1, 2, 3-triaryl substituted indole ring with rigid structure fluorescence function has a chemical structural formula as follows:

the preparation method comprises the following steps: indole ring is used as a construction framework, palladium acetate is used as a catalyst, and the synthesis is carried out by a one-pot method, wherein the reaction flow is as follows:

the method comprises the following steps:

s01, putting 450uL halogenated aromatic hydrocarbon, 1.146g naphthylamine, 712mg tolane, 90mg palladium acetate and 672mg sodium bicarbonate into a round-bottom flask, uniformly mixing, and then adding 40mLDMF (sodium dodecyl benzene sulfonate) to obtain a mixed solution;

s02, reacting the mixed solution in an oil bath kettle at 110 ℃ for 18h, cooling, filtering through a short silica gel plug, and removing the solvent by spinning to obtain a crude mixture;

s03, purifying by column chromatography (n-hexane/ethyl acetate, 100: 0) to obtain a white solid product with the mass of 0.2300g, the yield of 20% and the fluorescence excitation wavelength of 310 nm.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the equivalent replacement or change according to the technical solution and the inventive concept of the present invention should be covered by the scope of the present invention.

Claims (3)

1. A1, 2, 3-triaryl substituted indole ring with rigid structure fluorescence function is characterized in that the chemical structural formula is as follows:

。

2. the 1,2, 3-triaryl substituted indole ring with rigid structure fluorescence function according to claim 1, wherein the preparation method comprises: indole ring is used as a construction framework, palladium acetate is used as a catalyst, the synthesis is carried out by a one-pot method, the reaction flow is shown as follows,

。

3. the 1,2, 3-triaryl substituted indole ring having rigid structure fluorescent function according to claim 1, wherein the preparation steps are as follows:

s01, putting 450uL of halogenated aromatic hydrocarbon, 728uL of aniline, 712mg of tolane, 90mg of palladium acetate and 672mg of sodium bicarbonate into a round-bottom flask, uniformly mixing, and then adding 40mLDMF (sodium dodecyl benzene sulfonate) to obtain a mixed solution;

s02, reacting the mixed solution in an oil bath kettle at 110 ℃ for 18h, cooling, filtering through a short silica gel plug, and removing the solvent by spinning to obtain a crude mixture;

s03, purifying by column chromatography (n-hexane/ethyl acetate, 99: 1) to obtain a white solid product with a mass of 186mg, a yield of 50% and a fluorescence excitation wavelength of 310 nm.

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