CN112778791B - A kind of antimony complex dye (SbDIPY) and preparation method - Google Patents

Abstract

An antimony complex dye (SbDIPY) and a preparation method thereof, relating to a dye and a preparation method, the invention provides a novel antimony complex dye (azadipyrrin‑antimony (VI): aza‑SbDIPY), and a preparation method thereof, and the efficiency with which singlet oxygen is produced. The dye is a new series of dyes developed for the first time using aza-SbDIPY, which is developed by complexing SbF ₅ with aza-dipyrromethene ligands. The dye has a structural formula as shown in formula I/II/III. The dye has the advantages of classic traditional dyes BODIPY/aza‑BODIPY spectral properties. The central atom Sb is six-coordinated, and this new type of aza‑SbDIPY has a higher extinction coefficient and long-wave absorption from the visible to the near-infrared region. Aza‑SbDIPY can tolerate trace amounts of water, and its application can be explored under low humidity conditions. Aza‑SbDIPY can be used as a photosensitizer, which can be applied to the generation of singlet oxygen.

Description

A kind of antimony complex dye (SbDIPY) and preparation method

technical field

The invention relates to a dye and a preparation method, in particular to an antimony complex dye (SbDIPY) and a preparation method.

Background technique

Azadipyrromethene, reported by M. Rogers in 1943, consists of two pyrroles linked by a methine bridge. As a classical bidentate ligand, azafluoroborondipyrromethene (aza-BODIPY) formed by complexing with _BF2 group shows high-intensity absorption in the near-infrared region, high fluorescence quantum yield, and chemically and photochemically stable sex. As a bidentate ligand, Azadipyrromethene has also been explored to complex with different metals (Zn, Cu, Co, Ni, Hg, etc.) to form metal dipyrrole complexes, which have a variety of specific properties.

Among them, azafluoroboron dipyrromethene dyes are a new class of fluorescent dyes that have received widespread attention in recent years. This type of dye has long absorption and emission wavelengths, good photostability, narrow half-peak width, high quantum yield, and molar extinction coefficient. Large and many other characteristics, the disadvantage is that the molecule is difficult to modify. It has a good application prospect in the field of biological analysis and has become a research hotspot in recent years.

The applicant once designed and disclosed the first example of PnO2-PODIPY dye, a new dye PnO2-PODIPY/PnO2-azaPODIPY developed from the classic traditional BODIPY/azaBODIPY, referred to as PnO2-PODIPY. In addition to the spectral properties of classic and traditional BODIPY/azaBODIPY dyes, the biggest feature is good water solubility. Antimony and its compounds are found in various fields of fundamental and applied chemistry. The reaction of synthesizing group 15 element compounds with specific structures and superatomic valences has attracted more and more attention. In particular, the applicant has done long-term research on the pentacoordinate compound 10-Pn-5 (Pn: P, As, Sb, Bi) in experimental and theoretical chemistry. Also, Sb-BODIPY derivatives, namely 10-Sb-5 species, showed strong affinity for anions including fluoride and cyanide, and their reactions elicited a fluorescent switch response.

For unstable hexacoordinated antimony complexes, only a few hexacoordinated organoantimony complexes have been reported so far.

Therefore, the applicant introduced antimony into azadipyrromethene for the first time to construct a new functional six-coordinated organic antimony dye. Based on the early accumulation of superatom chemistry and BODIPY dyes, a new strategic design is introduced here to develop a new type of azadipyrrin-antimony(VI) (aza-SbDIPY) dye, which is developed by complexing SbF ₅ with azadipyrromethene aza-SbDIPY is a novel family of dyes for the mother nucleus. As a new type of dye, the new aza-SbDIPY has a higher extinction coefficient and long-wavelength absorption from visible light to near-infrared region. Aza-SbDIPY can tolerate trace amounts of water, can exist stably, and its efficiency of singlet oxygen generation can be explored under low humidity conditions.

Contents of the invention

The object of the present invention is to provide a kind of antimony complex dye (SbDIPY) and preparation method, antimony complex dye central atom is complexed with Sb hexacoordinated dye, has very good extinction coefficient, and from visible light to near-infrared region long-wavelength absorption. Aza-SbDIPY can tolerate trace amounts of water and can exist stably, allowing its efficiency in generating singlet oxygen under low humidity conditions.

The purpose of the present invention is achieved by the following technical solutions:

An antimony complex dye (SbDIPY), its structural formula is shown in formula I/II/III:

.

As for the antimony complex dye (SbDIPY), the central atom of the dye is antimony (Sb), a hexa-coordinated Group 15 element.

A method for preparing an antimony complex dye (SbDIPY), the method comprising the following steps: at room temperature and in air, the bidentate ligand azadipyrromethene VII/VIII/IX is dissolved in a dichloromethane solvent, and SbF ₅ , and the mixture was stirred for 0.5 h, and the mixture was obtained by filtration; n-hexane was slowly added, and the product was recrystallized and purified by a dichloromethane/n-hexane mixed solvent to obtain a quantitative product (97%-98%) in the form of a black-green solid aza - SbDIPY, its structural formula I/II/III:

The antimony complex dye (SbDIPY), which is used as a photosensitizer, generates singlet oxygen under the irradiation of long-wavelength monochromatic light.

Advantage and effect of the present invention are:

The invention designs and synthesizes a new type of dye aiming at the deficiency of the existing dye, and enriches the types of the dye family. At the same time, this dye has a molecule that is easy to modify.

The aza-SbDIPY dye of the invention has optical properties and can be used as a photosensitizer to generate singlet oxygen.

The aza-SbDIPY dye of the invention has low toxicity, easy to obtain raw materials, simple structure and easy preparation.

The aza-SbDIPY dye of the present invention has a higher extinction coefficient and a wider half-peak width.

The aza-SbDIPY dyes of the present invention are sensitive to water.

The aza-SbDIPY dye of the present invention can exist stably under a small amount of water, which can allow the exploration of its singlet oxygen generation efficiency under low humidity conditions.

Description of drawings

Fig. 1 is the structural formula I of novel aza-SbDIPY dyestuff of the present invention;

Fig. 2 is the structural formula II of novel aza-SbDIPY dyestuff of the present invention;

Fig. 3 is the structural formula III of novel aza-SbDIPY dyestuff of the present invention;

Fig. 4 is the ¹ H NMR nuclear magnetic resonance spectrum of novel aza-SbDIPY dyestuff I of the present invention;

Fig. 5 is the ¹⁹ F NMR nuclear magnetic resonance spectrum of novel aza-SbDIPY dye I of the present invention;

Fig. 6 is the ¹ H NMR nuclear magnetic resonance spectrum of novel aza-SbDIPY dye II of the present invention;

Fig. 7 is the ¹⁹ F NMR nuclear magnetic resonance spectrum of novel aza-SbDIPY dye II of the present invention;

Fig. 8 is the ¹ H NMR nuclear magnetic resonance spectrum of novel aza-SbDIPY dye III of the present invention;

Fig. 9 is the ¹⁹ F NMR spectrum of the novel aza-SbDIPY dye III of the present invention;

Fig. 10 is the high-resolution mass spectrum of novel aza-SbDIPY dye I of the present invention;

Fig. 11 is the high-resolution mass spectrum of novel aza-SbDIPY dye II of the present invention;

Fig. 12 is the high-resolution mass spectrum of novel aza-SbDIPY dye III of the present invention;

Fig. 13 is the absorption spectrum of the novel aza-SbDIPY dye of the present invention in CH ₂ Cl ₂ at 298K. Among them, 1a, 1b, 1c represent azadipyrromethene VII/VIII/IX respectively; 2a, 2b, 2c represent the photos of aza-SbDIPYs dye I/II/III respectively;

Fig. 14 is the theoretical calculation comparison chart of the novel aza-SbDIPY dye III of the present invention and the traditional aza-BODIPY dye III-1;

Fig. 15 is the absorption spectrum of the novel aza-SbDIPY dye II of the present invention in MeCN-H ₂ O (2.5 ml) containing different moisture. The inset graph shows the absorption changes of the new aza-SbDIPY dye II in the presence of 0, 0.005, 0.01, 0.015, 0.02, 0.025, 0.3, 0.035 and 0.04ml of H ₂ O;

Figure 16 utilizes the novel aza-SbDIPY dye II of the present invention to produce singlet oxygen through irradiation, which is used to oxidize DPBF with absorption at 416nm over time;

Figure 17 is the degradation characteristics and absorption curves of the novel aza-SbDIPY dye of the present invention and 1,3-diphenylisobenzofuran in MeCN after light irradiation.

Detailed ways

The present invention will be described in detail below in conjunction with the embodiments shown in the accompanying drawings.

The first aspect of the present invention aims at the deficiencies of existing BODIPY/azaBODIPY dyes, improves on the basis thereof, and provides a class of simple structure, long wavelength, with higher extinction coefficient and wider half-width novel Compound aza-SbDIPY. It has the following structural formula I/II/III:

I/II/III

In another aspect of the present invention, an open system is adopted to synthesize under air, and the steps are as follows:

(1) Add excess NaH into a round bottom flask, wash with dry n-hexane three times under nitrogen protection; add dry DMSO and corresponding ketone dropwise, stir at room temperature for half an hour, add compound 2-phenylazacyclopropene, React at room temperature for 2 h, then quench with ice water, extract with dichloromethane, wash and dry, and perform column chromatography to obtain pyrrole IV/V/VI.

IV/V/VI

(2) Under an open system, add corresponding pyrrole, glacial acetic acid, and acetic anhydride to a round-bottomed flask, add sodium nitrite in an ice-water bath, react at room temperature for 0.5 h, wash with sodium bicarbonate, extract with dichloromethane, and spin dry . Using dichloromethane as the eluent and alumina as the stationary phase to pass through the column, the solvent was spin-dried to obtain azamethine dipyrrole VII/VIII/IX blue-green solid.

VII/VIII/IX

(3) Precursors VII/VIII/IX were dissolved in CH ₂ Cl ₂ solution at room temperature in air, SbF ₅ was added, and the mixture was stirred for 0.5 h, and the resulting mixture was filtered. Add n-hexane slowly, and recrystallize and purify the product through CH ₂ Cl ₂ /n-hexane mixed solvent, and almost quantitative product (97%-98%) is obtained. Aza-SbDIPY is obtained as a black-green solid with the structural formula I/II/III.

I/II/III

In another aspect of the present invention, based on the above experimental basis, a reaction mechanism for the synthesis of aza-SbDIPY is proposed. The electron pair from the N atom in the azadipyrromethene VII first attacks the central atom Sb, and then the vertical bond of SbF ₅ is broken, and F ^- is cleaved. The hydrogen of the pyrrole in the intermediate is then attacked by the nucleophile ^F- to give the target compound I. To the best of our knowledge, this is the first synthesis of aza-SbDIPY.

Schematic diagram of the synthesis of aza-SbDIPY.

aza-SbDIPY was found to have optical properties. Compared with the absorption maximum (598 nm) of precursor VII, the absorption maximum of aza-SbDIPY dye I is 634 nm, which is red-shifted by 36 nm. A noticeable change in the color of the solution from blue to green. Similarly, the aza-SbDIPYs dyes II (692 nm) and III (724 nm) were significantly red-shifted compared with the corresponding precursors VIII (616 nm) and IX (634 nm), respectively. Compared with the typical aza-BODIPY dyes II-1 (688 nm) and III-1 (706 nm), the aza-SbDIPYs dyes II and III absorb at 692 nm and 724 nm and are unexpectedly red-shifted by 4 nm and 18nm.

II-1/III-1

Aza-SbDIPY is sensitive to water. A clear response of dye II (1.2 x 10 ^-5 M) to water (0-0.4 ml) was observed. With the increase of water content, the absorption band at 700 nm gradually decreased and the blue-shifted band at 620 nm increased, and the aza-SbDIPY dye II was completely converted to its precursor VIII when 0.4 ml _H2O was added. Regardless, aza-SbDIPY is stable in the presence of trace amounts of water, thus allowing their smooth synthesis in air.

The present invention adopts a one-pot method to prepare the dye described in the present invention, and azadipyrrin-antimony (VI) (aza-SbDIPY) developed by complexing _SbF5 with azadipyrromethene is a new series of dyes with the mother nucleus.

Specific embodiments are as follows.

(1) Add excess NaH into a round bottom flask, wash with dry n-hexane three times under nitrogen protection; add dry DMSO and corresponding ketone dropwise, stir at room temperature for half an hour, add compound 2-phenylazacyclopropene, React at room temperature for 2 h, then quench with ice water, extract with dichloromethane, wash and dry, and perform column chromatography to obtain pyrrole IV/V/VI.

IV/V/VI

(2) Under an open system, add corresponding pyrrole, glacial acetic acid, and acetic anhydride to a round-bottomed flask, add sodium nitrite in an ice-water bath, react at room temperature for 0.5 h, wash with sodium bicarbonate, extract with dichloromethane, and spin dry . Using dichloromethane as the eluent and alumina as the stationary phase to pass through the column, the solvent was spin-dried to obtain azadipyrromethene VII/VIII/IX as a blue-green solid.

VII/VIII/IX

(3) Precursors VII/VIII/IX were dissolved in CH ₂ Cl ₂ solution at room temperature in air, SbF ₅ was added, and the mixture was stirred for 0.5 h, and the resulting mixture was filtered. Add n-hexane slowly, and purify the product by recrystallization from CH ₂ Cl ₂ /n-hexane to obtain almost quantitative product (97%-98%) in the form of black-green solid aza-SbDIPY with the structural formula I/II/III .

I/II/III

For the above-mentioned compounds of the present invention, nuclear magnetic resonance spectra including ¹ H, ¹⁹ F NMR nuclear magnetic resonance spectra, mass spectrometry, etc. are used to determine their structures.

Example 1

Preparation of aza-SbDIPY Dye III

(1) Synthesis of pyrrole VI containing naphthalene ring.

(2) Add 150 mg of NaH into the round bottom flask, under nitrogen protection, wash with dry n-hexane (10 ml) three times; drop dry DMSO (5 ml), 6-methoxy-2-acetyl Naphthalene (200 mg, 1 mmol) was stirred at room temperature for half an hour, compound 2-phenylaziridine (175 mg, 1.5 mmol) was added, reacted at room temperature for 2 h, and quenched with ice water. Adjust to neutral with dilute hydrochloric acid, extract with dichloromethane, wash, dry over anhydrous magnesium sulfate, and perform column chromatography on the eluent ( n -hexane: CH ₂ Cl ₂ = 1: 1) to synthesize off-white pyrrole with ring structure VI (89 mg, 30%). ¹ H NMR (500 MHz, CDCl ₃ ): δ (ppm)8.56 (br s, 1H), 7.84 (d, ⁴ J = 1.5 Hz, 1H), 7.77 (d, ³ J = 8.5 Hz, 1H), 7.74 (d, ³ J = 9.0 Hz, 1H), 7.67 (dd, ³ J = 9.0 Hz, ⁴ J = 2.0 Hz, 1H), 7.60 (dd, ³ J = 8.5 Hz, ⁴ J = 1.5 Hz, 2H), 7.37 (t, ³ J = 8.0 Hz, 2H), 7.18-7.22 (m, 2H), 7.16 (dd, ³ J = 9.0 Hz, ⁴ J = 2.0 Hz, 1H), 7.13 (d, ⁴ J = 2.0 Hz , 1H), 6.90-6.91(m, 1H), 3.93 (s, 3H). MS (ESI(+)): m/z = 300.1 [M+H] ⁺ , found 300.1.

(3) In an open system, add pyrrole VI (60 mg, 0.2 mmol), glacial acetic acid (1 ml), acetic anhydride (0.5 ml), add sodium nitrite (6.9 mg, 0.1 mmol) under ice-water bath, and add Reacted for 0.5 h, washed with sodium bicarbonate, extracted with dichloromethane, and spin-dried. Use dichloromethane as the eluent, use alumina as the stationary phase to pass through the column, and spin the solvent to obtain azamethine dipyrrole IX dark blue solid.

(4) Synthesis of Aza-SbDIPY dye.

_SbF5 (8.4 μL, 0.11 mmol) was added to a solution of precursor IX (68.2 mg, 0.11 mmol) in _CH2Cl2 (10 _mL ) at room temperature in air, and the mixture was stirred at room temperature for 0.5 h . Then, the mixture was obtained by filtration. Add n-hexane (5 mL) slowly, and pass through CH ₂ Cl ₂ /n-hexane mixed solvent, recrystallize and purify the product to obtain III (86.3 mg, 97%) as a black-green solid. ¹ H NMR (400 MHz, CD ₂ Cl ₂ ): δ (ppm) 7.86 (s, 2H), 7.78 (t, ³ J = 8.0 Hz, 4H), 7.69 (d, ³ J = 8.0 Hz, 2H), 7,59 (d, ³ J = 8.0 Hz, 4H), 7.36 (t, ³ J = 8.0 Hz, 4H), 7.14-7.23(m, 6H), 6.91 (s, 2H), 3.92 (s, 6H). ¹⁹ F NMR (376MHz, CD ₂ Cl ₂ ): δ (ppm) -135.8 (br s, 4F). FTMS-MALDI (m/z): [M+H] ⁺ calcd for C ₄₂ H ₃₁ F ₄ N ₃ O ₂ Sb: 806.1391, found 806.1392.

Detection of singlet oxygen.

Using UV spectrophotometry tracking method, 1,3-diphenylisobenzofuran (DPBF) was used as singlet oxygen scavenger, and the efficiency of photosensitizer to generate singlet oxygen was evaluated by detecting the decrease of DPBF absorbance. Monochromatic light (680 nm, 0.5 mW/cm ² ) was used. The degradation characteristics and absorption curves of DPBF (aza-BODIPY in MeCN Dye II λ _abs = 696 nm).

Photosensitizers carry out the DPBF degradation mechanism under light conditions.

Compared with heavy atom (Br or I) modified aza-BODIPY photosensitizers, the singlet oxygen generation effect of Br/I-free aza-SbDIPY was investigated. Using the 1,3-diphenylisobenzofuran (DPBF) method, it was found that aza-SbDIPY II with an antimony atom as the central atom was able to generate singlet oxygen, although the ability of aza-SbDIPY to generate singlet oxygen was lower than that of aza-BODIPY . The experimental results show that aza-SbDIPY II is stable under light and has no photobleaching phenomenon.

The above content is a further detailed description of the present invention in conjunction with specific optimized implementation modes, and it cannot be assumed that the specific implementation of the present invention is limited to these descriptions. For those of ordinary skill in the technical field to which the present invention belongs, on the premise that the core idea of the present invention is to complex the Sb with the azadipyrromethene ligand, some simple deductions and substitutions can also be made, such as other modified aza Both dipyrromethene and common dipyrromethene bidentate ligand complexes with Sb should be regarded as belonging to the protection scope of the present invention. As a person of ordinary skill in the technical field to which the present invention belongs, under the consideration of the functionalization of the dye used in the photosensitizer based on the present invention, several other functional enhancements can be made, such as cell imaging, molecular probes, fluorescent materials, photosensitizing dyes , photothermal dyes, etc., and other applications that can obtain the compound of the present invention should be considered as belonging to the protection scope of the present invention.

Claims (3)

1. a kind of antimony complex dye is characterized in that, its structural formula is as shown in formula I/II/III: . 2. a kind of antimony complex dye according to claim 1, is characterized in that, the preparation method of described antimony complex dye is: at room temperature, in air, bidentate ligand azadipyrromethene VII/VIII /IX was dissolved in dichloromethane solvent, SbF ₅ was added, and the mixture was stirred for 0.5 h, and the mixture was obtained by filtration; n-hexane was slowly added, and the product was recrystallized and purified by dichloromethane/n-hexane mixed solvent to obtain the quantitative formula: 97%-98% of the product, which is a dark green solid aza-SbDIPY, its structural formula I/II/III: . 3. The antimony complex dye according to claim 1, characterized in that, the dye is used as a photosensitizer to generate singlet oxygen under long-wavelength monochromatic light irradiation.