CN113150017A

CN113150017A - Coupled double-BODIPY near-infrared absorption dye and preparation method thereof

Info

Publication number: CN113150017A
Application number: CN202110138882.8A
Authority: CN
Inventors: 徐海军; 王怡; 宋宇婷; 孙磊; 蔡正春
Original assignee: Nanjing Forestry University
Current assignee: Nanjing Forestry University
Priority date: 2021-02-02
Filing date: 2021-02-02
Publication date: 2021-07-23

Abstract

The invention relates to a coupled double-BODIPY near-infrared absorption dye and a preparation method thereof, which is prepared by FeCl₃/CH₃NO₂Under the catalytic action, a C-C covalent bond is formed at the beta position of a parent body of 3, 5- ((4-N, N diethyl) -divinylbenzene) -8- (1-naphthalene) -BODIPY, and the coupled double BODIPY near infrared absorption dye is synthesized. The preparation method has the advantages of simple reaction steps, mild reaction conditions and good selectivity. The dye has the strongest electronic absorption spectrum red shifted to 796nm, narrow absorption peak in near infrared region and molar extinction coefficient greater than 2.5X 10⁵cm^‑1mol^‑1And L has good application prospect in the fields of organic solar cells, near-infrared light dynamic therapy, biological fluorescence imaging and the like.

Description

Coupled double-BODIPY near-infrared absorption dye and preparation method thereof

Technical Field

The invention belongs to the technical field of organic synthesis and fine chemical engineering, and particularly relates to a coupled double-BODIPY near-infrared absorption dye and a preparation method thereof.

Background

Near infrared absorption/fluorescent dyes are the research hot spots in the field of optical molecules at present, and the absorption and emission bands are 650-1100 nm. In the near infrared spectrum range, biological autofluorescence, absorption of tissues and cells and the like can be reduced to the minimum, the influence of scattered light and fluorescence of substances on a test result is greatly reduced, the analysis sensitivity is improved, and meanwhile, the damage to organisms can be reduced. Therefore, near infrared absorbing/fluorescent dyes have incomparable advantages in biological detection. In recent years, high-performance near-infrared dyes have been widely used in the fields of biosensing, medical imaging, nonlinear optics, solar cells, and the like. Therefore, designing and preparing the novel near-infrared dye with excellent performance is a research focus in recent years and is also a key link for promoting the development and application of the near-infrared dye.

BODIPY is a fluorescent dye with excellent performance, compared with other fluorescent dyes, such as azo dyes, quinone dyes, phthalocyanine dyes and the like, the BODIPY has higher fluorescence quantum yield and molar extinction coefficient, good photo-thermal stability, difficult influence of solvent polarity and environmental pH value on a fluorescence signal, narrower spectrum absorption/emission band, and can be used as a good fluorescent identification material in terms of sensitivity; by modifying the structure, the absorption and emission wavelength can be adjusted to the near infrared region, so that the BODIPY fluorescent dye is widely applied to the aspects of fluorescent probes, biological monitoring, solar cells and the like, and becomes a research hotspot of organic fluorescent compounds in recent years.

Typically, the electron absorption spectrum of BODIPY dyes is centered around 500nm, which interferes with fluorescence bioimaging. The characteristic that the parent structure of the BODIPY molecule is easy to modify can be utilized to expand a pi conjugated system of the molecule, so that the absorption wavelength and the emission wavelength of the molecule are subjected to red shift. Through Knoevenagel condensation reaction, different aromatic aldehydes can be condensed with 3, 5-methyl of a BODIPY matrix to generate styryl, so that a conjugated structure is enlarged, the reaction preparation method is simple, the reaction selectivity is good, and the red shift of the absorption wavelength of the aromatic aldehydes to a region above 750nm is difficult to realize only through structural modification; in addition, although the 2, 6 position of the modified BODIPY parent structure can expand a conjugated system, reduce the HOMO-LUMO energy level and promote the spectrum to generate red shift, most of the methods need to introduce halogen first and then carry out palladium-catalyzed cross coupling, so that the problems of multiple synthesis steps, high reaction toxicity, expensive catalyst and the like exist, and the application of the method in the fields of biomedicine and the like is limited. Therefore, a simple and efficient synthesis method is developed, a C-C covalent bond is directly formed at the beta position of the BODIPY matrix, and the novel fluorescent dye with long absorption/emission wavelength and excellent photophysical properties is obtained, so that the method has important scientific significance and application value.

Disclosure of Invention

The purpose of the invention is as follows: aiming at the defects in the prior art, the invention aims to provide a coupled double BODIPY near infrared absorption dye. The invention also aims to provide a preparation method of the coupled double BODIPY near-infrared absorption dye.

The technical scheme is as follows: in order to achieve the purpose of the invention, the invention adopts the technical scheme that:

the invention relates to a coupled double BODIPY near-infrared absorption dye and a preparation method thereof, which are characterized in that the structural formula is as follows:

a preparation method of a coupled double-BODIPY near-infrared absorption dye derivative comprises the following steps:

1) adding dried dichloromethane and monomer BODIPY derivative into a round-bottom flask under anhydrous and oxygen-free conditions, reducing the temperature of a reaction system to-78 ℃, and dropwise adding FeCl containing FeCl by using a sample injector₃Nitromethane (CH)₃NO₂) Reacting the solution for 10-30 minutes; wherein, monomer BODIPY derivative and FeCl₃The molar ratio of (A) to (B) is 1: 10-15.

2) And (3) heating the reaction product to room temperature, adding saturated sodium bicarbonate solution to quench the reaction, separating an organic layer, washing with water, drying with anhydrous sodium sulfate, distilling under reduced pressure to remove the organic solvent, and separating and purifying the residue by silica gel column chromatography, wherein an eluent is 100% dichloromethane to obtain a black-brown solid product (I).

The specific chemical reaction formula is as follows:

in the step 1), monomer BODIPY derivative and FeCl₃The molar ratio of (A) to (B) is 1: 10-15.

In the step 1), the molar ratio of the monomer BODIPY derivative to the nitromethane is 1: 250-300.

In the step 2), the eluent for silica gel column chromatography is 100% dichloromethane.

The invention has the advantages of

Compared with the prior art, the coupled double BODIPY near infrared absorption dye and the preparation method thereof have the advantages that: (1) the preparation method is simple and easy to implement, the reaction selectivity is good, and the beta positions of two monomer BODIPY form C-C covalent bonds to obtain the BODIPY derivatives absorbing in near infrared, and the method can be used as an effective preparation method and popularized and applied to the synthesis of coupled double BODIPY derivatives and near infrared absorption dyes. (2) The dye has a narrow absorption peak and a high molar extinction coefficient in a near infrared region, and has good application prospects in the fields of organic solar cells, near infrared region photodynamic therapy, bioluminescence imaging and the like.

Drawings

FIG. 1 is a drawing of Compound I¹H-NMR spectrum;

FIG. 2 is a diagram showing an ultraviolet-visible absorption spectrum of Compound I.

Detailed Description

The invention is further described below with reference to the specific drawings.

By using¹H-NMR and ESI-MS characterize and confirm the structure of the BODIPY dye. The detection instrument is as follows: bruker ARX600 nuclear magnetic resonance spectrometer (TMS as internal standard, deuterated chloroform as solvent), Shimadzu UV-3100 UV-visible spectrophotometer (scan range 300-900 nm, light path slit 2 nm).

Example 1

Dried dichloromethane (50mL) and 3, 5- ((4-N, N-diethyl) -divinylbenzene) -8- (1-naphthalene) -BODIPY (100mg, 0.15mmol) were added to a round-bottomed flask in the absence of water and oxygen, the reaction temperature was lowered to-78 deg.C, and FeCl-containing solution was added dropwise with a sample injector₃(364mg, 2.25mmol) of nitromethane solution(2.4mL), react for 30 min; the reaction system was warmed to room temperature, and saturated sodium bicarbonate solution was added to quench the reaction, the organic layer was separated, washed with water, dried over anhydrous sodium sulfate, and distilled under reduced pressure to remove the organic solvent, and the residue was separated and purified by silica gel column chromatography with an eluent of 100% dichloromethane to give product I (29mg, 29%) as a dark brown solid.¹H-NMR(600MHz，CDCl₃): δ 7.84-7.87(t, J ═ 8.4Hz, 4H), 7.80-7.82(t, J ═ 7.2Hz, 2H), 7.62-7.64(d, J ═ 16.2Hz, 2H), 7.53-7.58(m, 6H), 7.42-7.47(m, 4H), 7.36-7.40(m, 6H), 7.28(s, 1H), 7.18-7.24(m, 5H), 6.78(s, 2H), 6.67-6.69(d, J ═ 9.0Hz, 4H), 6.60-6.61(d, J ═ 7.8Hz, 4H), 6.39(d, J ═ 4.2Hz, 2H), 6.28(s, 2H), 3.40-3.42(m, J ═ 7.8Hz, 4H), 6.39(d, J ═ 4.2H), 2H, 6.28(s, 2H), 3.40-3.42(m, 3.8, t ═ 7.1.12H), 1.1H, 1H, 12H, 1H, 12H); ESI-MS (ESI): calcd for C₈₆H₈₄B₂F₄N₈[M+H]⁺：1327.70；found：1327.72。

UV-vis: 350nm, 458nm, 556nm, 796nm (FIG. 2).

Example 2

Dried dichloromethane (50mL) and 3, 5- ((4-N, N-diethyl) -divinylbenzene) -8- (1-naphthalene) -BODIPY (100mg, 0.15mmol) were added to a round-bottomed flask in the absence of water and oxygen, the reaction temperature was lowered to-78 deg.C, and FeCl-containing solution was added dropwise with a sample injector₃(243mg, 1.5mmol) of nitromethane solution (2.0mL) and reacted for 30 min; the reaction system was warmed to room temperature, and saturated sodium bicarbonate solution was added to quench the reaction, the organic layer was separated, washed with water, dried over anhydrous sodium sulfate, and distilled under reduced pressure to remove the organic solvent, and the residue was separated and purified by silica gel column chromatography with an eluent of 100% dichloromethane to give product I (18mg, 18%) as a dark brown solid.

Example 3

Dried dichloromethane (50mL) and 3, 5- ((4-N, N-diethyl) -divinylbenzene) -8- (1-naphthalene) -BODIPY (100mg, 0.15mmol) were added to a round-bottomed flask in the absence of water and oxygen, the reaction temperature was lowered to-78 deg.C, and FeCl-containing solution was added dropwise with a sample injector₃(292mg, 1.8mmol) in nitromethane (2.4mL) and reacted20 min; the reaction system was warmed to room temperature, and saturated sodium bicarbonate solution was added to quench the reaction, the organic layer was separated, washed with water, dried over anhydrous sodium sulfate, and distilled under reduced pressure to remove the organic solvent, and the residue was separated and purified by silica gel column chromatography with an eluent of 100% dichloromethane to give product I (22mg, 22%) as a dark brown solid.

Example 4

Dried dichloromethane (50mL) and 3, 5- ((4-N, N-diethyl) -divinylbenzene) -8- (1-naphthalene) -BODIPY (100mg, 0.15mmol) were added to a round-bottomed flask in the absence of water and oxygen, the reaction temperature was lowered to-78 deg.C, and FeCl-containing solution was added dropwise with a sample injector₃(292mg, 1.8mmol) in nitromethane (2.2mL) for 20 min; the reaction system was warmed to room temperature, and saturated sodium bicarbonate solution was added to quench the reaction, the organic layer was separated, washed with water, dried over anhydrous sodium sulfate, and distilled under reduced pressure to remove the organic solvent, and the residue was separated and purified by silica gel column chromatography with an eluent of 100% dichloromethane to give product I (20mg, 20%) as a dark brown solid.

Claims

1. A coupled double BODIPY near infrared absorption dye (I) is characterized in that the structural formula is as follows:

2. the process of claim 1, wherein the coupling bis BODIPY near infrared absorbing dye is prepared by: at-78 deg.C in FeCl₃/CH₃NO₂Under the catalytic action, a C-C covalent bond is formed at the beta position of the BODIPY monomer to obtain a coupled double BODIPY near-infrared absorption dye compound, and the method comprises the following steps:

1) under the anhydrous and oxygen-free conditions, adding dry dichloromethane and monomer BODIPY derivative into a reaction vessel, reducing the temperature of the reaction system to-78 ℃, and dropwise adding FeCl containing FeCl by using a sample injector₃CH (A) of₃NO₂A solution; wherein, monomer BODIPY derivative and FeCl₃In a molar ratio of1∶10～15；

2) And (3) heating the reaction system to room temperature, adding saturated sodium bicarbonate solution to quench the reaction, separating an organic layer, washing with water, drying with anhydrous sodium sulfate, distilling under reduced pressure to remove the organic solvent, and separating and purifying the residue by silica gel column chromatography, wherein an eluent is 100% dichloromethane to obtain a black-brown solid product (I).

3. The method for preparing a coupled bis-BODIPY near-infrared absorbing dye according to claim 2, wherein in the step 1), the monomeric BODIPY derivative and FeCl₃The molar ratio of (A) to (B) is 1: 10-15.

4. The method for preparing a coupled bis-BODIPY near-infrared absorbing dye according to claim 2, wherein in the step 1), the molar ratio of the BODIPY derivative to nitromethane is 1: 250-300.

5. The method according to claim 2, wherein the reaction time is controlled to 10 to 30 minutes in the specific step.

6. The coupled bis-BODIPY near-infrared absorbing dye of claim 1, wherein the absorption maximum wavelength is red-shifted to 796nm and the molar extinction coefficient is greater than 2.5 x 10⁵cm^-1mol^-1L。