CN107759775B - Donor-receptor type alternating polymer containing sulfone-based fused ring structure and having strong two-photon effect, preparation method and application - Google Patents

Abstract

The invention discloses a donor-receptor type alternating polymer containing a sulfone fused ring structure and having a strong two-photon effect, and a preparation method and application thereof. The preparation method of the invention takes the sulfone-containing fused ring structure as an electron-deficient group, reasonably selects an electron-rich group, and prepares the donor-acceptor type alternating polymer with the sulfone-containing fused ring structure and the strong two-photon effect through Suzuki polymerization. The donor-acceptor type alternating polymer containing the sulfone-based fused ring structure has strong single-photon fluorescence and two-photon fluorescence intensity, has good solubility, can be dissolved in a common organic solvent, is convenient for testing and applying two-photon absorption performance, and has practical application value in the field of nonlinear optics.

Description

Donor-Acceptor-Type Alternating Polymerization with Strong Two-Photon Effect in Sulfone-Containing Condensed Ring Structures Material, preparation method and application

technical field

The invention belongs to the field of two-photon fluorescent polymers, in particular to a donor-acceptor-type alternating polymer containing a sulfone group fused ring structure and having a strong two-photon effect, and a preparation method and application thereof.

Background technique

In 1931, Goppert-Mayer first proposed the concept of two-photon absorption, and theoretically calculated the transition probability of the two-photon process. After the material passes through the intermediate virtual state (represented by V in Figure 1, V ₁ and V ₂ can be equal or not equal) under the action of strong light (such as laser) and absorbs the energy of two photons at the same time (hv ₁ +hv ₂ ), The process of transition from the ground state S ₀ to the excited state _Sn (the _Sn energy level is the energy of two photons) is called two-photon absorption (TPA). Due to the limitations of experimental conditions, it was not until the advent of lasers in the early 1960s that Kaiser observed this phenomenon for the first time in experiments, confirming Goppert-Mayer's prediction. Two-photon absorption is a nonlinear optical phenomenon. With the rapid progress of laser technology, researchers have made more and more in-depth exploration of two-photon absorption. In addition to being a spectral result, it is more widely used in three-dimensional information storage. , two-photon up-conversion laser, two-photon absorption light limiting, two-photon fluorescence microscopy, photodynamic therapy and other fields.

The most important features of materials with strong two-photon absorption are the large conjugated system and strong electron donating/withdrawing ability in the molecular structure. The sulfone group is a strong electron-deficient group. When it is used to build a multi-component fused ring structure, it can not only make the new unit retain the strong electron-withdrawing function of the sulfone group, but also show strong intramolecular charge transfer when introduced into the molecular chain. ; and the multi-component structure endows the new unit with better planarity and rigidity, which makes the new unit have a higher fluorescence quantum yield. The presence of sulfone groups is beneficial to the two-photon response of polymer materials.

SUMMARY OF THE INVENTION

In order to solve the shortcomings and deficiencies of the prior art, the primary purpose of the present invention is to provide a donor-acceptor-type alternating polymer containing a sulfone group fused ring structure with a strong two-photon effect. The polymer is a D-A type sulfone group-containing polymer, and has the characteristics of better solubility, higher fluorescence quantum yield and strong two-photon response.

Another object of the present invention is to provide a preparation method of the donor-acceptor-type alternating polymer containing a sulfone group fused ring structure and having a strong two-photon effect. In the method, the sulfone group-containing fused ring structure is used as the electron-deficient unit, the electron-rich unit matching the electron-deficient unit is selected, and the sulfone group-containing fused ring structure with strong two-photon effect is prepared by Suzuki polycondensation reaction. Donor-type alternating polymers.

Another object of the present invention is to provide the application of the donor-acceptor-type alternating polymer containing a sulfone group fused ring structure and having a strong two-photon effect.

The object of the present invention is achieved through the following technical solutions:

A donor-acceptor-type alternating polymer with a strong two-photon effect containing a sulfone-based fused ring structure, the structural formula of which is shown in formula (1):

In the formula, A is the electron-deficient unit, and D is the electron-rich unit.

The structure of the described electron-deficient unit A is any one of the following structures:

以及

R₃选自H、C₁～C₃₀的直链或者支链烷基、以及C₁～C₃₀的烷氧基。In the preferred structural formula of the above-mentioned electron-deficient unit A, R is selected from H, C ₁ -C ₃₀ straight-chain or branched-chain alkyl,

as well as

R ₃ is selected from H, C ₁ -C ₃₀ straight or branched chain alkyl, and C ₁ -C ₃₀ alkoxy.

The electron-rich unit D is any one of the following structural formulas:

以及

R₃选自H、C₁～C₃₀的直链或者支链烷基、以及C₁～C₃₀的烷氧基；In the preferred structural formula of the above electron-rich unit D, R is selected from H, C ₁ -C ₃₀ linear or branched alkyl,

as well as

R ₃ is selected from H, C ₁ -C ₃₀ straight or branched chain alkyl, and C ₁ -C ₃₀ alkoxy;

以及

R₈选自H、C₁～C₃₀的直链或者支链烷基、以及C₁～C₃₀的烷氧基。R ₁ , R ₂ , R ₄ to R ₇ may be the same or different and independently selected from H, linear or branched alkyl of C ₁ to C ₃₀ , alkoxy of C ₁ to C ₃₀ ,

as well as

R ₈ is selected from H, C ₁ -C ₃₀ straight or branched chain alkyl, and C ₁ -C ₃₀ alkoxy.

The preparation of the donor-acceptor-type alternating polymer containing a sulfone group fused ring structure and having a strong two-photon effect mainly lies in the synthesis of an electron-deficient unit A and an electron-rich unit D.

The preparation of the donor-acceptor-type alternating polymer containing a sulfone group-containing fused ring structure and having a strong two-photon effect is obtained by Suzuki polymerization of a sulfone group-containing fused ring structure A and an electron-rich unit D.

Further, the preparation method of the donor-acceptor-type alternating polymer with a strong two-photon effect containing a sulfone-based condensed ring structure comprises the following steps:

(1) Under an inert gas atmosphere, the sulfone-based fused-ring structural monomer A and the electron-rich unit D are dissolved in toluene, add palladium acetate, tricyclohexyl phosphorus and tetraethylammonium hydroxide aqueous solution, heat and stir, and the temperature is between 60 and 110 ℃, react for 24-36 hours;

(2) add phenylboronic acid to end cap, and continue to react for 6 to 12 hours; then add bromobenzene to end cap, and continue to react for 6 to 12 hours;

(3) after the polymerization is completed, the reaction solution is precipitated in methanol, filtered, extracted with methanol, acetone and n-hexane successively, then toluene is used as the eluent, and the silica gel column is subjected to column chromatography, concentrated, and precipitated again in In methanol solution, filter and dry to obtain the sulfone group-containing fused ring structure and the donor-acceptor-type alternating polymer with strong two-photon effect.

Further, the inert gas in step (1) includes argon;

Further, the mol ratio of electron-deficient unit A and electron-donating unit D described in step (1) is 1:1;

Further, the molar ratio of palladium acetate, tricyclohexyl phosphorus and electron-deficient unit A described in step (1) is 1:2:100～150;

Further, the volume ratio of the tetraethylammonium hydroxide aqueous solution and toluene described in step (1) is 1:6～10.

Further, the molar ratio of phenylboronic acid:bromobenzene:electron-deficient unit described in step (2) is 0.2-0.5:2-5:1.

The application of the donor-acceptor-type alternating polymer with a strong two-photon effect containing a sulfone-based fused ring structure in the field of nonlinear optics includes two-photon fluorescence microscopy, two-photon up-conversion laser, optical Applications in clipping, two-photon three-dimensional processing, two-photon three-dimensional optical storage, two-photon photodynamic therapy, etc.

Further, in the application process, the strength of the two-photon absorption performance of the donor-acceptor-type alternating polymer with a strong two-photon effect of the sulfone group-containing fused ring structure is measured by the two-photon absorption cross-section, and the two-photon absorption cross-section value is The larger the value, the stronger the two-photon absorption ability of the compound containing S,S-dioxy-dibenzothiophene unit, and the faster the response.

Further, the test method of the two-photon absorption cross-section is: dissolve the donor-acceptor-type alternating polymer containing a sulfone-based fused ring structure with a strong two-photon effect in an organic solvent, and then use a two-photon induced fluorescence method. , Z-scan technology, nonlinear transmittance method or two-photon transient absorption spectroscopy test.

Further, the organic solvent includes toluene, xylene, n-hexane, diethyl ether, dioxane, dichloromethane, chloroform, ethyl acetate, tetrahydrofuran, 1,2-dichloroethane, N,N - Dimethylformamide, N,N-dimethylacetamide, acetone, dimethylsulfoxide or chlorobenzene.

Compared with the prior art, the present invention has the following advantages and beneficial effects:

(1) in the donor-acceptor type alternating polymer with strong two-photon effect containing sulfone group fused ring structure of the present invention, the sulfone group is a strong electron-deficient group, and the electronegativity is stronger than fluorine, ester group, carbonyl group, etc., Therefore, the unit of fused ring structure containing sulfone group has strong electron-withdrawing ability, and the connected electron-rich unit has strong intramolecular charge transfer effect, which can greatly improve the two-photon absorption response of the polymer.

(2) The donor-acceptor-type alternating polymer with a strong two-photon effect containing a sulfone group fused ring structure of the present invention has a higher fluorescence quantum yield due to its larger conjugation length, which is beneficial to enhancing the compound two-photon absorption capacity.

(3) The donor-acceptor-type alternating polymer with a strong two-photon effect and a sulfone group-containing fused ring structure of the present invention has strong one-photon fluorescence and two-photon fluorescence intensity, and has good solubility at the same time, and can be dissolved in commonly used organic In the solvent, it is convenient to test and apply the two-photon absorption performance, and has practical application value in the field of nonlinear optics.

Description of drawings

Figure 1 is a two-photon absorption (TPA) energy level diagram;

Fig. 2 is the single photon fluorescence spectrum of polymer P1 in different polar solvents;

Fig. 3 is the two-photon fluorescence spectrum of polymer P2 in toluene solution under different laser wavelengths;

Figure 4 is a graph showing the relationship between the two-photon absorption cross-section of the polymer P1 and the laser wavelength in different polar solvents;

FIG. 5 is a graph showing the relationship between the two-photon absorption cross sections of polymers P2 to P4 in toluene solution and the laser wavelength.

Detailed ways

The present invention will be described in further detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto. It should be understood that the appended claims summarize the scope of the present invention, and those skilled in the art should realize that changes made to the various embodiments of the present invention will be covered by the claims of the present invention under the guidance of the inventive concept. The spirit and scope of the book are covered.

Example 1: Synthesis of 1,4-dihexyloxybenzene

Under the protection of argon, add p-diphenol (11g, 0.10mol), tetrabutylammonium bromide (0.32g, 1.00mmol), 50wt% sodium hydroxide aqueous solution (20g/20ml deionized) into a 500ml two-necked flask water, 0.5 mmol) and toluene solvent (200 ml). The mixture was heated and stirred, and when the temperature stabilized to 80° C., n-hexyl bromide (36.31 g, 0.22 mmol) was added. After 6 hours of reaction, the reaction was terminated, the organic layer was separated, concentrated, and the crude product was purified by column chromatography using petroleum ether as the eluent to finally obtain 25.1 g of a white solid with a yield of 91%. The results of ¹ H NMR, ¹³ C NMR, MS and elemental analysis showed that the obtained compound was the target product, and the chemical reaction equation was as follows:

Example 2: Synthesis of 1,4-dibromo-2,5-dihexyloxybenzene

Under light-proof conditions, add 1,4-dihexyloxybenzene (10g, 35.9mmol) and carbon tetrachloride (150ml) to a 250ml single-neck reaction flask, and then add liquid bromine (12.6g, 79.0mmol) in three steps ). After 8 hours of reaction, saturated sodium bisulfite solution was added, extracted with dichloromethane, the organic phase was collected, concentrated, and the crude product was recrystallized from ethanol to obtain 13.47 g of white needle crystals, yield: 86%. The results of ¹ H NMR, ¹³ C NMR, MS and elemental analysis showed that the obtained compound was the target product, and the chemical reaction equation was as follows:

Example 3: 2,2'-(2,5-Dihexyloxy)-1,4-phenyl-bis-4,4,5,5-tetramethyl-1,3,2-dioxaboro Synthesis of Alkane

Into a 250 mL three-necked flask were added 1,4-dibromo-2,5-dihexyloxybenzene (15 g, 34.4 mmol) and 100 mL of anhydrous tetrahydrofuran. Under argon protection, 2.4M n-butyllithium/n-hexane solution (35.8 mL, 86 mmol) was added dropwise at -78°C, and the mixture was stirred at -78°C for 2 h. Then 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-ethylenedioxyborate (19.3 mL, 96.3 mmol) was added rapidly and stirring was continued at -78°C 1.5h. The reaction mixture was gradually warmed to room temperature, and the reaction was stirred for 10 h. The reaction solution was spin-dried, extracted with ethyl acetate, washed with NaCl aqueous solution, dried over anhydrous magnesium sulfate, and concentrated, and the crude product was purified by silica gel column chromatography, the eluent was petroleum ether/dichloromethane (3:1), 10.2 g of white solid were obtained, yield: 56%. The results of ¹ H NMR, ¹³ C NMR, MS and elemental analysis showed that the obtained compound was the target product, and the chemical reaction equation was as follows:

Example 4: Synthesis of 2',5'-dihexyloxy-2'2"-dimethylsulfinyl-1,1';4'1"-terphenyl

Under the protection of argon, 2,2'-(2,5-dihexyloxy)-1,4-phenyl-bis-4,4,5,5-tetramethyl- 1,3,2-dioxaborane (9.21 g, 50 mmol), 1-bromo-2-methanesulfinylbenzene (), tetrabutylammonium bromide (), tetrakistriphenylphosphine palladium () and 100ml of toluene solvent, heated to 110°C with stirring, added 50wt% potassium carbonate aqueous solution (24.6ml, 125mmol), and reacted for 24 hours; the solvent was spin-dried, the crude product was purified by silica gel column chromatography, and the eluent was petroleum ether/dichloromethane (4:1), 10.2 g of light yellow viscous liquid was obtained, yield: 74%. The results of ¹ H NMR, ¹³ C NMR, MS and elemental analysis showed that the obtained compound was the target product, and the chemical reaction equation was as follows:

Example 5: Synthesis of Compound M1

2',5'-Dihexyloxy-2'2"-dimethylsulfinyl-1,1';4'1"-terphenyl (8.6 g, 15.5 mmol) was added to 10 mL of trifluoro at room temperature methanesulfonic acid, stirred at room temperature for 20 h, and then the reaction was added dropwise to ice water. Then, the reaction solution was suction filtered to obtain pale yellow solid powder and air-dried. The pale yellow solid powder was added to 100 mL of pyridine, and heated under reflux for 6 h under nitrogen. The reaction was quenched and cooled to room temperature, extracted and the excess pyridine was neutralized with hydrochloric acid. Column chromatography with pure petroleum ether and recrystallization from ethanol gave a yellow powdery solid (2.43 g, 32%). The results of ¹ H NMR, ¹³ C NMR, MS and elemental analysis showed that the obtained compound was the target product, and the chemical reaction equation was as follows:

Example 5: Synthesis of Compound M2

Compound M1 (1.80 g, 3.67 mmol) and iodine (46 mg, 0.18 mmol) were added to 40 ml of dichloromethane, and in the dark, liquid bromine (1.29 g, 8.07 mmol) was added dropwise, and the reaction was carried out for 10 hours; Saturated aqueous sodium bisulfite solution was added to the system, and when the system was colorless, the organic phase was separated, concentrated, and the crude product was purified by column chromatography using petroleum ether as the eluent to finally obtain 1.55g of yellow solid with a yield of 65%. . The results of ¹ H NMR, ¹³ C NMR, MS and elemental analysis showed that the obtained compound was the target product, and the chemical reaction equation was as follows:

Example 6: Synthesis of Compound M3

Compound M2 (1.2 g, 1.85 mmol) and 3-chloroperoxybenzoic acid (3.4 g, 20 mmol) were dissolved in 120 mL of dichloromethane, and after stirring for 5 h, the reaction solution was poured into cold 10% mass concentration of hydrogen Stir in sodium oxide aqueous solution for 30 min. The organic layer was washed three times with water, and the organic phase was collected, concentrated and purified by a chromatography column. The eluent was dichloromethane/ethyl acetate (volume ratio: 1:2), and then recrystallized from ethanol to obtain a yellow solid (1.12 g, 85%). The results of ¹ H NMR, ¹³ C NMR, MS and elemental analysis showed that the obtained compound was the target product, and the chemical reaction equation was as follows:

Example 7: Synthesis of 4-n-octyltriphenylamine

Dissolve 4-octylbromobenzene (2.69g, 10mmol) and aniline (0.93g, 23mmol) with 150ml of toluene solution, then add sodium tert-butylate (3.94g, 41mmol) and palladium acetate (96mg, 0.5mmol) , under argon protection, the oil bath was heated to 85 ° C, and the toluene solution of tri-tert-butylphosphine (1.0 mol/L, 0.5 mL) was added; after 12 hours of reaction, water was added to the reaction solution to quench the reaction, Extracted with dichloromethane three times, the organic phase was washed three times with deionized water, dried, concentrated, and the crude product was separated and purified by silica gel column chromatography. Pure petroleum ether was used as the eluent to obtain a white solid. Yield 82%. The results of ¹ H NMR, ¹³ C NMR, MS and elemental analysis showed that the obtained compound was the target product, and the chemical reaction equation was as follows:

Example 8: Synthesis of 4,4'-dibromo-4"-octyltriphenylamine

Completely dissolve 4-n-octyltriphenylamine (2.50 g, 7 mmol) with 20 ml of N,N-dimethylformamide, and at 0 °C, add dropwise N-bromosuccinimide (NBS, 2.74 g, 15.4mmol) of N,N-dimethylformamide solution, reacted for 4 hours under dark conditions; poured the reaction solution into water, stirred, filtered, and the filter cake was separated and purified by silica gel column chromatography, and pure petroleum ether was used as the leaching method. lotion to give a white solid. Yield 78%. The results of ¹ H NMR, ¹³ C NMR, MS and elemental analysis showed that the obtained compound was the target product, and the chemical reaction equation was as follows:

Example 9: 4,4'-bis(4,4',5,5'-tetramethyl-1,3,2-dioxaborane-diyl)-phenyl)-4"-octyl Synthesis of Triphenylamine

Completely dissolve 4,4'-dibromo-4"-octyltriphenylamine (2.58g, 5mmol) with 100ml of anhydrous tetrahydrofuran (THF) solution, under argon protection, cool down to -78°C, add dropwise 5.3ml of The n-hexane solution of n-butyllithium (concentration is 2.4mol L ^-1 ), after 1 hour of reaction, 2-isopropoxy-4,4,5,5-tetramethyl-1,3, 2-isopropoxy-4,4,5,5-tetramethyl-1,3, 2-Ethylenedioxyborate (2.6 g, 14 mmol) was continued to stir for 2 hours; the reaction system was gradually raised to room temperature for 24 hours; the reaction solution was concentrated, extracted with ethyl acetate three times in turn, and the organic phase was washed with deionized water After washing three times, drying and concentration, the crude product was separated and purified by silica gel column chromatography, and the mixed solvent of petroleum ether/ethyl acetate (5/1, v/v) was used as the eluent to obtain a white solid. The yield was 69%. ¹ The results of HNMR, ¹³ C NMR, MS and elemental analysis show that the obtained compound is the target product, and the chemical reaction equation is as follows:

Example 10: Synthesis of 3,6-dibromocarbazole

Completely dissolve carbazole (1.67 g, 10 mmol) with 300 ml of dichloromethane solution, add 30 g of 100-200 mesh silica gel, and add N-bromosuccinimide in three batches under ice bath conditions (0°C). (NBS, 3.92g, 22mmol), reacted under dark conditions for 12 hours; then the reaction solution was suction filtered, the filter cake was washed 5 times with dichloromethane, the organic phase was collected, dried, concentrated, and the crude product was filtered with dichloromethane/petroleum Ether (5/100, v/v) was recrystallized three times to give a white solid. Yield 83%. The results of ¹ H NMR, ¹³ C NMR, MS and elemental analysis showed that the obtained compound was the target product, and the chemical reaction equation was as follows:

Example 11: Synthesis of 3,6-dibromo-N-isooctylcarbazole

Completely dissolve 3,6-dibromocarbazole (2.28g, 7mmol) with 80ml of toluene solution, then add tetrabutylammonium bromide (0.11g, 0.35mmol), under argon protection, the oil bath is heated to 85°C, Continue to add 50wt% sodium hydroxide (2.8g/2.8ml deionized water, 70mmol) aqueous solution, after stirring for 1 hour, add isooctyl bromide (2.03g, 10.5mmol) rapidly; after 8 hours of reaction, add water to The reaction was quenched in the reaction solution, extracted three times with dichloromethane, the organic phase was washed three times with deionized water, dried, concentrated, and the crude product was separated and purified by silica gel column chromatography, using pure petroleum ether as the eluent to obtain a white solid. Yield 94%. The results of ¹ H NMR, ¹³ C NMR, MS and elemental analysis showed that the obtained compound was the target product, and the chemical reaction equation was as follows:

Example 12: Synthesis of 3,6-bis(4,4',5,5'-tetramethyl-1,3,2-dioxaborane-diyl)-N-isooctylcarbazole

Completely dissolve 3,6-dibromo-N-isooctylcarbazole (2.19g, 5mmol) with 100ml of anhydrous THF, under argon protection, cool down to -78℃, add 2.4mol L ^-1 of n-butyl dropwise n-hexane solution of lithium lithium (5.3 ml, 12.5 mmol), after 1 hour of reaction, 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-ethylenedioxy was added at one time boronate (2.79 g, 15 mmol) and stirring was continued for 2 hours. The reaction system was gradually raised to room temperature and reacted for 24 hours; the reaction solution was concentrated, extracted three times with ethyl acetate in turn, the organic phase was washed three times with deionized water, dried, concentrated, and the crude product was separated and purified by silica gel column chromatography, petroleum ether/ Ethyl acetate (6/1, v/v) mixed solvent was used as eluent to obtain a white solid. Yield 67%. The results of ¹ H NMR, ¹³ C NMR, MS and elemental analysis showed that the obtained compound was the target product, and the chemical reaction equation was as follows:

Example 13: Synthesis of 2,7-dibromo-N-isooctylcarbazole

Completely dissolve 2,7-dibromocarbazole (3.25g, 10mmol) with 80ml of toluene, then add tetrabutylammonium bromide (0.16g, 0.5mmol), under argon protection, the oil bath is heated to 85°C, and the Add 50wt% sodium hydroxide (4.0g/4.0ml deionized water, 0.1mol) aqueous solution, after stirring for 1 hour, add isooctyl bromide (2.32g, 12mmol) rapidly; after 8 hours of reaction, add water to the reaction The reaction was quenched in the liquid, extracted three times with dichloromethane, the organic phase was washed three times with deionized water, dried, concentrated, and the crude product was separated and purified by silica gel column chromatography, using pure petroleum ether as the eluent to obtain a white solid. Yield 94%. The results of ¹ H NMR, ¹³ C NMR, MS and elemental analysis showed that the obtained compound was the target product, and the chemical reaction equation was as follows:

Example 14: Synthesis of 2,7-bis(4,4',5,5'-tetramethyl-1,3,2-dioxaborane-diyl)-N-isooctylcarbazole

Completely dissolve 2,7-dibromo-N-isooctylcarbazole (3.5g, 8mmol) with 100ml of anhydrous tetrahydrofuran (THF) solution, under argon protection, cool down to -78°C, add 2.4mol dropwise L ^-1 of n-butyllithium in n-hexane solution (8.4ml, 20mmol), after 1 hour of reaction, 2-isopropoxy-4,4,5,5-tetramethyl-1,3, 2-isopropoxy-4,4,5,5-tetramethyl-1,3, 2-Ethylenedioxyboronic acid ester (4.17g, 22.4mmol), continued to stir for 2 hours; the reaction system was gradually raised to room temperature for 24 hours; the reaction solution was concentrated, extracted three times with ethyl acetate in turn, and the organic phase was deionized After washing with water three times, drying, and concentration, the crude product was separated and purified by silica gel column chromatography, and a mixed solvent of petroleum ether/ethyl acetate (6/1, v/v) was used as the eluent to obtain a white solid. Yield 67%. The results of ¹ H NMR, ¹³ C NMR, MS and elemental analysis showed that the obtained compound was the target product, and the chemical reaction equation was as follows:

Example 15: Synthesis of cyclohexane-1,4-dicarbonyl-bis(3-bromophenyl)hydrazone

Dissolve 3-bromophenylhydrazine hydrochloride (11.2 g, 50 mmol) and sodium acetate (4.1 g, 50 mmol) with 200 ml of ethanol, stir and mix well; under argon protection, slowly add 1,4-cyclohexanedione (2.81 g, 25mmol) in ethanol solution (100ml), then the oil bath was warmed up to 60°C and reacted for 5 hours; after the reaction was stopped, the reaction solution was poured into ice water, stirred, and the filter cake was separated by suction filtration, and washed with ice ethanol to obtain a brown color Solid, the yield is 75%, the solid is dried at low temperature and protected from light, and it is directly used in the next reaction without treatment. The results of ¹ H NMR, ¹³ C NMR, MS and elemental analysis showed that the obtained compound was the target product, and the chemical reaction equation was as follows:

Example 16: Synthesis of 3,9-dibromoindole[3,2-b]carbazole

Dissolve cyclohexane-1,4-dicarbonyl-bis(3-bromophenyl)hydrazone (5.0g, 11mmol) with 100ml glacial acetic acid/concentrated sulfuric acid mixed solution (volume ratio 4/1), stir under ice bath condition Mix well; then, the oil bath is heated to 50°C, and the reaction is performed for 5 hours; then the temperature is raised to 90°C, and the reaction is performed for 12 hours; after the reaction is stopped, the reaction solution is poured into ice water, stirred, and the filter cake is separated by suction filtration, and washed with ice ethanol , a yellowish-brown crude product was obtained, which was recrystallized with DMF to obtain a yellowish-green needle-like solid with a yield of 25%. The results of ¹ H NMR, ¹³ CNMR, MS and elemental analysis show that the obtained compound is the target product, and the chemical reaction equation is as follows:

Example 17: Synthesis of 3,9-dibromo-5,11-bis(9-hexadecyl)indole[3,2-b]carbazole

Dissolve 3,9-dibromoindole[3,2-b]carbazole (2.0 g, 4.8 mmol) and tetrabutylammonium bromide (154 mg, 0.48 mmol) with 40 ml of dimethyl sulfoxide solution; under argon Under the protection, the oil bath was heated to 60°C, and 50wt% sodium hydroxide (2.7g/2.7ml deionized water, 48mmol) aqueous solution was added, and after stirring for 1 hour, bromohexadecane (4.4g, 14.2mmol) was added rapidly. ); after 12 hours of reaction, the reaction solution was poured into ice water, stirred, and the filter cake was separated by suction filtration, and washed with ethanol to obtain a yellow solid with a yield of 91%. The results of ¹ H NMR, ¹³ C NMR, MS and elemental analysis showed that the obtained compound was the target product, and the chemical reaction equation was as follows:

Example 18: 3,9-bis(4,4',5,5'-tetramethyl-1,3,2-dioxaborane-diyl)-5,11-bis(9-hexadecane) Synthesis of Alkyl)indole[3,2-b]carbazole

Dissolve 3,9-dibromo-5,11-bis(9-heptadecyl)indole[3,2-b]carbazole (1.0 g, 1.1 mmol) and doublet in 50 ml of dioxane solution Nalcohol borate (0.9g, 3.5mmol), under argon protection, the oil bath was heated to 80°C, and 1,1'-bisdiphenylphosphoricene palladium dichloride (40mg, 55μmol) was rapidly added , reacted for 12 hours; after the reaction was stopped, the reaction solution was concentrated, extracted three times with ethyl acetate in turn, the organic phase was washed three times with deionized water, dried, concentrated, and the crude product was separated and purified by silica gel column chromatography, petroleum ether/acetic acid Ethyl ester (5/1, v/v) mixed solvent was used as eluent to obtain pale yellow solid. Yield 56%. The results of ¹ H NMR, ¹³ C NMR, MS and elemental analysis showed that the obtained compound was the target product, and the chemical reaction equation was as follows:

The following are examples of polymerization reactions, applicable to any polymerization reaction of the same type.

Example 19: Synthesis of polymer P1

Under argon, 4,4'-bis(4,4',5,5'-tetramethyl-1,3,2-dioxaborolane-diyl)-phenyl)-4"- Octyltriphenylamine (304.7 mg, 0.50 mmol) and compound M3 (356.2 mg, 0.50 mmol) were dissolved in 12 ml of toluene, and then tetraethylhydroxylamine aqueous solution (1.5 ml, wt%=20%), palladium acetate (1.12 mg) were added , 5 μmol) and tricyclohexylphosphine (2.8 mg, 10 μmol); after heating to 80°C for 24 hours, phenylboronic acid (15 mg, 0.13 mmol) was added to cap for 6 hours, and then bromobenzene (0.25 ml, 2.0 mmol) was added to cap The reaction was stopped for 6 hours. After cooling, the organic phase was precipitated in methanol (200 ml), filtered, and dried. The crude product was extracted with methanol, acetone and n-hexane successively, and the polymer was dissolved in toluene. The lotion is purified by column chromatography with neutral alumina; the toluene solution of the polymer is concentrated, precipitated in methanol solution again, filtered and dried to obtain a fibrous polymer.

Figure 2 is the single photon fluorescence spectrum of polymer P1 in different polar solvents, the solvents are weakly polar toluene, medium polar tetrahydrofuran, dichloromethane, strong polar N,N-dimethylmethane amide. The maximum single-photon fluorescence intensity of the polymer in different solvents decreased with the increase of solvent polarity, and the maximum fluorescence intensity in toluene solvent was 1.58×10 ⁷ ; the maximum emission peak shifted from 525 nm (toluene solvent) to 572 nm (N, N-dimethylformamide solvent), the intramolecular charge transfer is obvious. This is beneficial to the enhancement of the ability of two-photon absorption.

Example 20: Polymer P2 synthesis

Under argon, 3,6-bis(4,4',5,5'-tetramethyl-1,3,2-dioxaborane-diyl)-N-isooctylcarbazole ( 265.7 mg, 0.50 mmol) and compound M3 (356.2 mg, 0.50 mmol) were dissolved in 12 ml of toluene, and then an aqueous solution of tetraethylhydroxylamine (1.5 ml, wt% = 20%), palladium acetate (1.12 mg, 5 μmol) and trimethylamine were added. Cyclohexylphosphine (2.8 mg, 10 μmol); heated to 80°C for 24 hours, then added phenylboronic acid (15 mg, 0.13 mmol) to cap for 6 hours, and then added bromobenzene (0.25 ml, 2.0 mmol) to cap for 6 hours; reaction After cooling, the organic phase was precipitated in methanol (200ml), filtered, and dried. The crude product was extracted with methanol, acetone, and n-hexane successively. The polymer was dissolved in toluene, and toluene was used as the eluent. The toluene solution of the polymer was concentrated, precipitated in methanol solution again, filtered and dried to obtain a fibrous polymer.

Figure 3 is the two-photon fluorescence spectrum of polymer P2 under different laser wavelengths in toluene solution; it can be seen from the figure that the two-photon fluorescence intensity of polymer P2 is above 10 ³ when the laser wavelength gradually increases from 720nm to 940nm. When the laser wavelength is 760 nm, the two-photon fluorescence intensity of the polymer is the highest at 1.97×10 ⁵ . The higher fluorescence intensity indicates that the polymer has a strong two-photon response.

Example 21: Polymer P3 synthesis

Under argon, 2,7-bis(4,4',5,5'-tetramethyl-1,3,2-dioxaborane-diyl)-N-isooctylcarbazole ( 265.7 mg, 0.50 mmol) and compound M3 (356.2 mg, 0.50 mmol) were dissolved in 12 ml of toluene, and then an aqueous solution of tetraethylhydroxylamine (1.5 ml, wt% = 20%), palladium acetate (1.12 mg, 5 μmol) and trimethylamine were added. Cyclohexylphosphine (2.8 mg, 10 μmol); heated to 80°C for 24 hours, then added phenylboronic acid (15 mg, 0.13 mmol) to cap for 6 hours, and then added bromobenzene (0.25 ml, 2.0 mmol) to cap for 6 hours; reaction After cooling, the organic phase was precipitated in methanol (200ml), filtered, and dried. The crude product was extracted with methanol, acetone, and n-hexane successively. The polymer was dissolved in toluene, and toluene was used as the eluent. The toluene solution of the polymer was concentrated, precipitated in methanol solution again, filtered and dried to obtain a fibrous polymer.

Example 22: Polymer P4 synthesis

Under argon protection, 3,9-bis(4,4',5,5'-tetramethyl-1,3,2-dioxaborane-diyl)-5,11-bis(9- Hexadecyl)indole[3,2-b]carbazole (478.6 mg, 0.50 mmol) and compound M3 (356.2 mg, 0.50 mmol) were dissolved in 12 ml of toluene, and an aqueous solution of tetraethylhydroxylamine (1.5 ml, wt%=20%), palladium acetate (1.12 mg, 5 μmol) and tricyclohexylphosphine (2.8 mg, 10 μmol); after heating to 80 °C for 24 hours, adding phenylboronic acid (15 mg, 0.13 mmol) to cap for 6 hours, Then bromobenzene (0.25ml, 2.0mmol) was added to cap for 6 hours; the reaction was stopped, after cooling, the organic phase was precipitated in methanol (200ml), filtered and dried, and the crude product was successively extracted with methanol, acetone and n-hexane. Extraction, dissolve the polymer with toluene, use toluene as eluent, and purify by column chromatography with neutral alumina; concentrate the toluene solution of the polymer, re-precipitate it in methanol solution, filter, and dry to obtain a fibrous polymer

Example 23: Two-photon absorption performance test of the donor-acceptor-type alternating polymer containing sulfone group fused ring structure

The two-photon absorption performance of the donor-acceptor-type alternating polymer containing sulfone-based fused ring structure according to the present invention was tested by the two-photon fluorescence induction method; in the experimental test, a Ti:sapphire femtosecond laser (Avesta TiF-100M) was used as the pump Pu light source, the laser pulse width is 80fs, the frequency is 84.5Hz, the laser excitation energy is 100mw, and the pulse length is 10mm quartz sample cell. Polymer P1 was dissolved in four solvents of different polarities, namely toluene, tetrahydrofuran, dichloromethane, and N,N-dimethylformamide; polymers P2 to P4 were dissolved in toluene solution, and the concentrations of all solutions were the same. is 1×10 ^{- 6} mol L ^-1 . The standard sample is 0.1 mol L ^-1 sodium hydroxide aqueous solution of fluorescein with a concentration of 1×10 ^-6 mol L ^-1 , and its fluorescence quantum yield is 88%. The fluorescence quantum yield test results of polymers P1-P4 in solution state are shown in Table 1.

Table 1 Fluorescence quantum yields of polymers P1～P4

It can be seen from Table 1 that the fluorescence quantum yield of polymer P1 is 73% in toluene solution state, and as the solvent polarity increases to N,N-dimethylformamide, the fluorescence quantum yield decreases to 5%. This indicates that the polymer P1 has a strong two-photon response potential in weakly polar toluene solution. It is also proved that the polarity of the solvent is an important factor affecting the two-photon response of the polymer. The fluorescence quantum yields of polymers P1-P4 in toluene solution are 73%, 51%, 65% and 67%, respectively. The higher fluorescence quantum yields indicate that polymers have a huge application in the field of two-photon absorption. prospect.

According to the fluorescence quantum yield of the polymer and the two-photon fluorescence spectrum, the two-photon absorption cross-section δ of the compound can be calculated. The calculation formula is as follows:

In the above formula, 1 represents the standard sample, 0.1mol L ^-1 sodium hydroxide aqueous solution of fluorescein; 2 represents the sample to be tested. I ₁ and I ₂ represent the integral area of the two-photon fluorescence spectrum of the standard sample and the sample to be tested, and the two-photon fluorescence spectrum diagrams are shown in 2 and 3. φ ₁ and φ ₂ represent the fluorescence quantum efficiency of the standard sample and the sample to be tested. C ₁ and C ₂ represent the solution concentration of the standard sample and the sample to be tested.

The relationship between the two-photon absorption cross-section of polymer P1 in different solvents and the laser wavelength is shown in Figure 4. It can be seen from the figure that in the state of different polar solvents, the two-photon absorption cross-section of polymer P1 is related to the laser wavelength. The changing trend of wavelength is the same. When the laser wavelengths are 760nm and 800nm, the two-photon absorption cross section of polymer P1 is larger. Among them, the largest in toluene solvent is 3657GM (1GM=10 ^-50 cm ^-4 sphoton ^-1 ), and the laser wavelength is 760 nm at this time;

When the laser wavelength is 800nm, the maximum two-photon absorption cross-section value of polymer P1 in tetrahydrofuran solvent is 348GM;

When the laser wavelength is 780nm, the maximum two-photon absorption cross section of polymer P1 in N,N-dimethylformamide solvent is 108GM;

From the two-photon absorption cross-section data of polymer P1 in different polar solvents, it can be seen that the polarity of the solvent has an important influence on the two-photon absorption properties of the material. Choosing a suitable solvent is beneficial to the performance of the two-photon absorption of the material.

The relationship between the two-photon absorption cross-section of polymers P2-P4 in toluene solvent and the laser wavelength is shown in Figure 5. It can be seen from the figure that when the laser wavelength is 780 nm, the two-photon absorption cross-section value of polymer P2 is The maximum is 1308GM;

When the laser wavelength is 720nm, the maximum two-photon absorption cross section of polymer P3 is 1005GM;

When the laser wavelength is 780nm, the maximum two-photon absorption cross-section of polymer P4 is 784GM;

Polymers P1-P4 have large two-photon absorption cross-section values in the whole test range, indicating that the donor-acceptor-type alternating polymer containing sulfone-based fused ring structure has good two-photon response and has practical application value.

The above-mentioned embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited by the above-mentioned embodiments, and any other changes, modifications, substitutions, combinations, The simplification should be equivalent replacement manners, which are all included in the protection scope of the present invention.

Claims (7)

1. a kind of donor-acceptor type alternating polymer with strong two-photon effect containing sulfone-based fused ring structure, is characterized in that, its structure is a kind of in following structure:

2. the preparation method of the donor-acceptor type alternating polymer with strong two-photon effect containing sulfone-based fused-ring structure according to claim 1, is characterized in that, by the monomer containing sulfone-based fused-ring structure A and the electron-rich The monomer of unit D is polymerized by Suzuki to obtain the donor-acceptor-type alternating polymer containing the sulfone group fused ring structure with strong two-photon effect; the sulfone group containing fused ring structure A is:

The electron-rich unit D is selected from the following structures:

3. the preparation method of the donor-acceptor type alternating polymer with strong two-photon effect containing sulfone-based fused ring structure according to claim 2, is characterized in that, described preparation method comprises the steps: (1) Under inert gas atmosphere, the monomer containing sulfone-based fused ring structure A and the monomer of electron-rich unit D are dissolved in toluene, add palladium acetate, tricyclohexyl phosphorus and tetraethylammonium hydroxide aqueous solution, heat and stir, The temperature is at 60～110℃, and the reaction is carried out for 24～36 hours; (2) add phenylboronic acid to end cap, and continue to react for 6 to 12 hours; then add bromobenzene to end cap, and continue to react for 6 to 12 hours; (3) after the polymerization is completed, the reaction solution is precipitated in methanol, filtered, extracted with methanol, acetone and n-hexane successively, then toluene is used as the eluent, and the silica gel column is subjected to column chromatography, concentrated, and precipitated again in In methanol solution, filter and dry to obtain the sulfone group-containing fused ring structure and the donor-acceptor-type alternating polymer with strong two-photon effect. 4. The preparation method of the donor-acceptor-type alternating polymer with a strong two-photon effect containing a sulfone-based fused ring structure according to claim 2, wherein the inert gas in step (1) comprises argon; The mol ratio of the sulfone group-containing fused ring structure A and the electron-rich unit D described in the step (1) is 1:1; The molar ratio of palladium acetate, tricyclohexyl phosphorus and sulfone group-containing fused ring structure A described in step (1) is 1:2:100～150; The volume ratio of the tetraethylammonium hydroxide aqueous solution and toluene described in the step (1) is 1:6～10. 5. the preparation method of the donor-acceptor-type alternating polymer with strong two-photon effect containing sulfone-based fused ring structure according to claim 2, is characterized in that, the phenylboronic acid described in step (2): bromobenzene : The molar ratio of electron-deficient units is 0.2 to 0.5:2 to 5:1. 6. The application of the donor-acceptor-type alternating polymer containing a sulfone group fused ring structure with strong two-photon effect according to claim 1 in the field of nonlinear optics. 7. The application according to claim 6, wherein the nonlinear optics field includes two-photon fluorescence microscopy, two-photon up-conversion laser, optical clipping, two-photon three-dimensional processing, two-photon three-dimensional optical storage and Two-photon photodynamic therapy.

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