A chiral photo-switch containing a dibenzothiophene skeleton and a preparation method and application thereof

Abstract

The application discloses a kind of chiral photo-switches containing dibenzothiophene skeleton and its preparation method and application, with one of structures shown in formula S1-S14: The application is based on the influence of stator 2,7-substituent effect on the photochemical properties of bistable chiral photo-switch derived from over-crowded olefin, realizes nearly quantitative bidirectional light switching;Photo-switch can be controlled by oxidation and reduction in addition to light control, and the sulfur in the switch skeleton can be further modified, with excellent structure modifiability and functional group compatibility, breaking through the limitation of original bistable chiral molecule single light control.

Description

Technical Field

[0001] This invention relates to the field of organic synthesis technology, specifically to a chiral photoswitch containing a dibenzothiophene framework, its preparation method, and its application. Background Technology

[0002] Molecular photoswitches can control molecular geometry in a waste-free, high-spatiotemporal-precision, and reversible manner, serving as the core building blocks for constructing photoresponsive dynamic functional systems. In recent years, classical photoswitching systems, represented by azobenzene, spiropyran, rigid stilbene, and diarylethylene, have continued to develop, while novel molecular frameworks such as hydrazones, acylhydrazones, donor-acceptor Stenhouse adducts (DASA), and hemithioindigo have emerged. Among these, crowded olefin molecular motors and photoswitches possess the outstanding advantages of simple and reliable structural design and photothermal synergistic unidirectional motion. Through precise control of the steric hindrance in fjord regions, they can achieve flexible customization of rotational rates and functional properties, demonstrating significant application potential in dynamic molecular systems.

[0003] Overcrowded olefin photoswitches, due to the inherent chiral characteristics near the core carbon-carbon bonds, can achieve stable helical chiral reversal and significant geometrical changes through light-driven processes, making them ideal building blocks for constructing dynamic photoresponsive systems. P-type bistable overcrowded olefin switches based on the fluorene-tetrahydrophenanthrene framework exhibit extremely high thermal stability in their metastable isomers, showing almost no thermal recovery at room temperature. They enable bidirectional reversible switching controlled by multiple wavelengths, and the two isomers show significant spectral differences and high steady-state photoconversion rates. However, existing switches of this type lack systematic structure-activity relationship guidance, the mechanism by which the bottom substituents affect photochemical performance remains unclear, and the synthetic routes are cumbersome, limiting their efficient design and large-scale application.

[0004] Therefore, developing overcrowded olefin chiral optical switches with easily modifiable structures, tunable quantum yields, and high light conversion efficiency, and establishing clear molecular design principles, is of great significance for promoting the development of chiral optical control materials and smart devices. Summary of the Invention

[0005] This invention addresses the shortcomings of existing technologies by providing a chiral photoswitch containing a dibenzothiophene skeleton, its preparation method, and its application. Based on the influence of the stator 2,7-substituent effect on the photochemical properties of the bistable chiral photoswitch derived from overcrowded olefins, near-quantitative bidirectional light switching is achieved. In addition to light-induced regulation, the photoswitch can also be regulated by redox reactions, and the sulfur in the switch skeleton can be further modified. It exhibits excellent structural modifiability and functional group compatibility, breaking through the limitations of single light-induced regulation of existing bistable chiral molecules. It possesses bistable properties in both solutions and liquid crystals, and can undergo reversible changes under the driving of two wavelengths.

[0006] To address the aforementioned technical problems, the first aspect of the present invention provides a dibenzothiophene-containing chiral optical switch having one of the structures shown in formulas S1-S14:

[0007] ;

[0008] In S1-S10, R1 represents hydrogen, bromine, methoxy, cyano, thiomethyl ether, aldehyde, pyridine, N-methylpyridine, p-n-pentylphenyl, and p-n-cyanophenyl, respectively.

[0009] In S13-S14, R2 represents hydrogen and aryl groups, respectively.

[0010] Furthermore, the preparation method of the dibenzothiophene-containing chiral photoswitch includes the following steps:

[0011] The compound of formula 3 was mixed with Lawson's reagent and reacted at 100-120 °C to obtain an intermediate; then the intermediate was reacted with 9-diazo-9H-fluorene, 2,7-dibromo-9-diazo-9H-fluorene or 2,7-dimethoxy-9-diazo-9H-fluorene in the presence of hexamethylphosphoric triamine to obtain a chiral photoswitch with a dibenzothiophene skeleton containing one of formulas S1-S3;

[0012] The structural formula of compound 3 is as follows:

[0013] .

[0014] Furthermore, the preparation method of compound 3 includes the following steps:

[0015] (1) 4-Bromodibenzothiophene and cyclobutanone react in the presence of n-butyllithium to give compound of formula 1;

[0016] (2) The compound of Formula 1 is mixed with cerium ammonium nitrate and reacted to obtain the compound of Formula 2;

[0017] (3) Mix diisopropylamine, n-butyllithium, hexamethylphosphoric triamine, compound of formula 2 and potassium iodide, and react to obtain compound of formula 3;

[0018] Intermediates 1-2 each have the structure shown in Equation 1-2:

[0019] .

[0020] Furthermore, the reaction temperatures for steps (1)-(2) are independently selected from -5 to 5℃; the reaction temperature for step (3) is -80 to -70℃.

[0021] Furthermore, the preparation method of the dibenzothiophene-containing chiral photoswitch includes the following steps:

[0022] A chiral photoswitch containing a dibenzothiophene skeleton is prepared by mixing the compound of formula S2 with zinc cyanide, dimethyl disulfide, N,-N-dimethylformamide, 4-pyridineboronic acid, 4-n-pentylphenylboronic acid or 4-n-cyanophenylboronic acid through a substitution reaction.

[0023] Furthermore, the preparation method of the dibenzothiophene-containing chiral photoswitch includes the following steps:

[0024] The S7 compound was mixed with iodomethane to produce the S8 chiral photoswitch containing a dibenzothiophene skeleton.

[0025] Furthermore, the preparation method of the dibenzothiophene-containing chiral photoswitch includes the following steps:

[0026] The compound of formula S1 is mixed with m-chloroperoxybenzoic acid and subjected to an oxidation reaction to obtain a chiral photoswitch of formula S11 or S12 containing a dibenzothiophene skeleton.

[0027] Furthermore, the preparation method of the dibenzothiophene-containing chiral photoswitch includes the following steps:

[0028] The S1 compound was mixed with diacetic acid iodobenzene and ammonium carbamate for a nucleophilic reaction to obtain the S13 chiral photoswitch containing a dibenzothiophene skeleton.

[0029] Furthermore, the preparation method of the dibenzothiophene-containing chiral photoswitch includes the following steps:

[0030] The compound of formula S13 was coupled with cesium carbonate and bromobenzene in the presence of palladium acetate and binaphthalene diphenylphosphine to obtain a chiral photoswitch of formula S14 containing a dibenzothiophene skeleton.

[0031] The second aspect of this invention provides the application of the dibenzothiophene-containing chiral optical switch described in the first aspect in the field of optics.

[0032] The beneficial effects of this invention are:

[0033] This invention achieves near-quantitative bidirectional light switching based on the effect of stator 2,7-substituents on the photochemical properties of bistable chiral photoswitches derived from overcrowded olefins.

[0034] In addition to light-induced modulation, the optical switch of this invention can also be modulated by redox reactions. Furthermore, the sulfur in the switch framework can be further modified, exhibiting excellent structural modifiability and functional group compatibility. It breaks through the limitation of single light-induced modulation of the original bistable chiral molecules, possesses bistable properties in both solutions and liquid crystals, and can undergo reversible changes under the driving of two wavelengths. Attached Figure Description

[0035] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the working mechanism of the dibenzothiophene-containing chiral photoswitch of the present invention;

[0037] Figure 2 This is the ultraviolet-visible absorption spectrum of the S1 compound of the present invention;

[0038] Figure 3 This is the ultraviolet-visible absorption spectrum of the S11 compound of the present invention;

[0039] Figure 4 This is the ultraviolet-visible absorption spectrum of the S12 compound of the present invention;

[0040] Figure 5 This is the ultraviolet-visible absorption spectrum of the S13 compound of the present invention;

[0041] Figure 6 This is a fatigue resistance test diagram of the S1 compound of the present invention;

[0042] Figure 7 This is a variation of the proton NMR spectrum of the S1 compound of the present invention;

[0043] Figure 8 This is a variation of the proton NMR spectrum of the S2 compound of the present invention;

[0044] Figure 9 This is a variation of the proton NMR spectrum of the S3 compound of the present invention;

[0045] Figure 10 This is the circular dichroism spectrum of the S2 compound of the present invention;

[0046] Figure 11 This is a schematic diagram of the HTP test of the present invention;

[0047] Figure 12 This is a property diagram of the S9 liquid crystal of the present invention. Detailed Implementation

[0048] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] Example 1

[0050] This embodiment relates to a method for preparing compound S1, including the following steps:

[0051] (1) Under a nitrogen atmosphere, 4-bromodibenzothiophene (13.2 g, 50 mmol) was dissolved in anhydrous diethyl ether (150 mL), cooled to 0 °C, and n-butyllithium (33 mL, 52.5 mmol) was slowly added dropwise using a syringe, resulting in a precipitate. The resulting yellow mixture was stirred at 0 °C for 1 h, and then cyclobutanone (4.3 mL, 55 mmol) was added, and stirring was continued for another 1 h, at which point the precipitate disappeared. The reaction solution was quenched with saturated ammonium chloride aqueous solution, extracted with ethyl acetate, washed successively with water and saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by recrystallization from n-pentane to give a white solid product, alcohol intermediate 1 (9.1 g, 36 mmol, 72%). .

[0052] The analytical data of the product are as follows: 1 H NMR (400 MHz, CDCl3) δ 8.19 – 8.13 (m, 1H),8.11 (dd, J = 7.0, 2.0 Hz, 1H), 7.89 – 7.84 (m, 1H), 7.52 – 7.41 (m, 4H), 2.83 – 2.74 (m, 2H), 2.59 – 2.48 (m, 2H), 2.29 (s, 1H), 2.14 (dtt, J = 11.2,9.3, 5.6 Hz, 1H), 1.75 (dtt, J = 11.1, 8.8, 7.0 Hz, 1H). 13 C NMR (101 MHz, CDCl3) δ 140.17, 139.37, 137.10, 136.99, 135.37, 126.91, 124.48, 124.34,122.90, 122.60, 121.66, 121.03, 78.02, 35.52, 13.91.

[0053] (2) Intermediate 1 (5.04 g, 20.0 mmol) was dissolved in a water-acetonitrile mixture (150 mL: 150 mL) and stirred at 0 °C for 2 min in an open-top round-bottom flask. Cerium ammonium nitrate (CAN, 11.0 g, 20.0 mmol) was then added, and the mixture was stirred at 0 °C for another 15 min. The reaction mixture was extracted with ethyl acetate (3 × 50 mL), and the organic phases were combined, washed successively with water and saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by column chromatography (silica gel, eluent: n-pentane / ethyl acetate = 40:1) to obtain a colorless solid intermediate 2 (1.46 g, 5.8 mmol, 29%). .

[0054] The analytical data of the product are as follows: 1 H NMR (400 MHz, CDCl3) δ 8.19 (d, J = 8.0 Hz,1H), 8.14 – 8.07 (m, 1H), 7.96 – 7.89 (m, 1H), 7.50 – 7.42 (m, 2H), 7.31 (d,J = 8.0 Hz, 1H), 3.11 (t, J = 6.1 Hz, 2H), 2.79 (dd, J = 7.2, 5.8 Hz, 2H), 2.21 (p, J = 6.3 Hz, 2H). 13 C NMR (101 MHz, CDCl3) δ 197.99, 144.73, 142.31,139.16, 135.48, 133.87, 126.76, 125.96, 125.24, 124.53, 122.90, 121.09,38.87, 30.13, 23.44.

[0055] (3) Under nitrogen protection, diisopropylamine (2.00 mL, 15.5 mmol) was dissolved in tetrahydrofuran (20 mL) and cooled to 0 °C. Butyllithium (1.6 M n-hexane solution, 8.40 mL, 13.4 mmol) was slowly added dropwise, and the mixture was stirred for 2 h. The reaction mixture was then cooled to -78 °C, and hexamethylphosphoric triamine (HMPA, 7.5 mL) was added, and the mixture was stirred for 1 h. Next, a tetrahydrofuran solution of intermediate 2 (2.8 g, 10.5 mmol) was slowly added dropwise, and the mixture was stirred at -78 °C for 2 h. Then, iodomethane (1.0 mL, 15.6 mmol) was added at -78 °C, and the mixture was stirred overnight. The reaction system was slowly brought to room temperature, quenched with saturated ammonium chloride aqueous solution, and extracted with ethyl acetate (20 mL × 3). The organic phase was washed successively with sodium bicarbonate aqueous solution, water, and saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography (eluent: n-pentane / dichloromethane = 3:1) to give intermediate 3 (2.05 g, 7.70 mmol, 74%), a white solid. .

[0056] The analytical data of the product are as follows: 1 H NMR (400 MHz, CDCl3) δ 8.28 (d, J = 8.0 Hz,1H), 8.20 – 8.13 (m, 1H), 7.99 – 7.93 (m, 1H), 7.53 – 7.46 (m, 2H), 7.38 (d,J = 7.9 Hz, 1H), 3.31 – 3.15 (m, 2H), 2.83 – 2.71 (m, 1H), 2.33 (dq, J =13.2, 4.4 Hz, 1H), 2.10 – 1.97 (m, 1H), 1.41 (d, J = 6.8 Hz, 3H). 13 C NMR (101MHz, CDCl3) δ 200.61, 144.59, 142.38, 139.43, 135.50, 133.98, 126.77, 126.58,125.85, 125.31, 124.55, 122.98, 121.11, 42.60, 31.58, 29.52, 15.65.

[0057] (4) Under a nitrogen atmosphere, Lawson's reagent (808 mg, 2.0 mmol) and 2-methyl-3,4-dihydrobenzo[b]naphtho[2,1-d]thiophene-1(2H)-one 3 (266.0 mg, 1.0 mmol) were dissolved in anhydrous toluene (32 mL). The mixture was heated and stirred at 110 °C for 18 h, and the reaction progress was monitored by thin-layer chromatography (TLC) (developing solvent: n-pentane / dichloromethane = 5:1). The reaction solution was directly purified by rapid column chromatography (silica gel, n-pentane / dichloromethane = 5:1), the green fraction was collected and concentrated under reduced pressure to obtain crude thione solid (197.4 mg, 0.7 mmol, 70%). 9-diazo-9H-fluorene (161.3 mg, 0.84 mmol) was dissolved in tetrahydrofuran under nitrogen protection, and the above thione tetrahydrofuran solution (3.6 mL) was added and stirred overnight. Hexamethylphosphoryltriamine (HMPT, 0.5 mL) was then added, and stirring continued for 24 h. The reaction mixture was poured into water and extracted with ethyl acetate. The combined organic layers were washed successively with water and saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography (n-pentane) to give the yellow solid product photoswitcher S1 (226.0 mg, 0.55 mmol, 78%).

[0058] The analytical data of the product are as follows: 1 H NMR (400 MHz, CDCl3) δ 8.09 (dd, J = 8.1, 5.4Hz, 2H), 7.99 – 7.93 (m, 1H), 7.77 – 7.71 (m, 1H), 7.58 (dd, J = 22.5, 7.7Hz, 2H), 7.39 – 7.25 (m, 5H), 7.06 (td, J = 7.4, 1.0 Hz, 1H), 6.64 (td, J =7.6, 7.2, 1.2 Hz, 1H), 6.54 (d, J = 8.0 Hz, 1H), 4.17 (h, J = 6.9 Hz, 1H),2.75 (ddd, J = 14.4, 5.0, 3.3 Hz, 1H), 2.59 (ddd, J = 14.3, 11.9, 5.6 Hz,1H), 2.39 (dddd, J = 13.5, 8.6, 5.6, 3.3 Hz, 1H), 1.24 (dd, J = 12.4, 5.4 Hz,1H), 1.18 (d, J = 6.9 Hz, 3H). 13C NMR (101 MHz, CDCl3) δ 145.70, 141.12,140.46, 139.97, 139.63, 138.09, 137.95, 135.92, 134.23, 132.84, 131.95,127.76, 127.42, 127.15, 126.38, 125.40, 124.29, 124.22, 124.08, 123.00,121.77, 121.32, 119.84, 119.11, 34.38, 30.94, 28.98, 21.11.

[0059] Example 2

[0060] The difference between this embodiment and Example 1 is that the 9-diazo-9H-fluorene in step (4) is replaced with 2,7-dimethoxy-9-diazo-9H-fluorene in equimolar form, while the other steps and parameters remain unchanged, and a yellow solid product photoswitch S2 (203.5 mg, 0.36 mmol, 51%) is prepared.

[0061] The analytical data of the product are as follows: 1 H NMR (400 MHz, CDCl3) δ 8.26 – 8.17 (m, 2H), 8.13 (d, J = 1.6 Hz, 1H), 7.67 (ddd, J = 8.0, 2.5, 1.5 Hz, 2H), 7.59 – 7.50(m, 2H), 7.29 (d, J = 1.7 Hz, 1H), 6.72 (d, J = 1.7 Hz, 1H), 4.19 – 4.10 (m,1H), 2.89 (ddd, J = 14.7, 5.0, 3.5 Hz, 1H), 2.70 (ddd, J = 14.5, 11.5, 5.7Hz, 1H), 2.50 (dddd, J = 13.5, 8.0, 5.7, 3.6 Hz, 1H), 1.41 – 1.34 (m, 1H), 1.29 (d, J = 7.0 Hz, 3H). 13C NMR (101 MHz, CDCl3) δ 149.12, 140.75, 140.48,139.61, 139.56, 139.51, 138.84, 137.36, 135.71, 134.51, 130.83, 130.66,130.40, 128.35, 127.42, 126.61, 124.41, 124.38, 122.94, 122.54, 121.49,121.29, 121.22, 121.06, 120.36, 34.66, 30.60, 28.77, 20.77.

[0062] Example 3

[0063] The difference between this embodiment and Example 1 is that the 9-diazo-9H-fluorene in step (4) is replaced with 2,7-dibromo-9-diazo-9H-fluorene, while the other steps and parameters remain unchanged, to prepare the yellow solid product photoswitch S3 (248.9 mg, 0.53 mmol, 75%).

[0064] The analytical data of the product are as follows: ¹H NMR (400 MHz, CDCl₃) δ 8.18 – 8.11 (m, 2H), 7.69 – 7.64 (m, 1H), 7.61 – 7.56 (m, 2H), 7.47 – 7.34 (m, 4H), 6.95 (dd, J = 8.3, 2.3 Hz, 1H), 6.68 (dd, J = 8.3, 2.4 Hz, 1H), 6.14 (d, J = 2.3 Hz, 1H), 4.20 (dt, J = 8.2, 6.5 Hz, 1H), 3.94 (s, 3H), 2.99 (s, 3H), 2.82 (ddd, J = 14.3, 4.7, 3.2 Hz, 1H), 2.64 (ddd, J = 14.1, 12.2, 5.4 Hz, 1H), 2.48 (dtd, J= 13.2, 5.3, 2.7 Hz, 1H), 1.30 (d, J = 6.9 Hz, 3H), 1.29 – 1.22 (m, 1H). 13CNMR (101 MHz, CDCl3) δ 152.54, 142.47, 140.99, 140.40, 140.25, 139.00,138.71, 138.65, 135.49, 134.77, 131.33, 131.12, 129.92, 129.36, 128.82,128.00, 126.84, 124.67, 124.59, 123.40, 122.65, 121.70, 121.27, 120.65,119.49, 119.09, 111.79, 111.59, 35.04, 30.05, 28.40, 20.62.

[0065] Example 4

[0066] This embodiment relates to a method for preparing compound S4, including the following steps:

[0067] Under nitrogen protection, compound S2 (57.0 mg, 0.1 mmol), zinc cyanide (14.3 mg, 0.12 mmol), chloro(2-di-tert-butylphosphine-2',4',6'-triisopropylbiphenyl) (2'-amino-1,1'-biphenyl-2-ylpalladium(II) (t-BuXPhos-Pd-G3, 8.1 mg, 0.01 mmol) and 2-di-tert-butylphosphine-2',4',6'-triisopropylbiphenyl (t-BuXPhos, 11.7 mg, 0.027 mmol) were dissolved in a degassed DMF (N,N-dimethylformamide) / H2O mixed solvent (6.7 mL DMF, 0.067 mL H2O), and heated and stirred at 100 °C for 12 h. After the reaction was complete, the mixture was poured into water (100 mL) and extracted with ethyl acetate (3 × 10⁻⁶). The organic phases were combined and washed successively with water and saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography (eluent: n-pentane / ethyl acetate = 2:1) to give a pale yellow solid product S4 (44.1 mg, 0.095 mmol, 95%).

[0068] The analytical data of the product are as follows: 1 H NMR (400 MHz, CDCl3) δ 8.32 (d, J = 1.2 Hz, 1H), 8.25 (d, J = 7.9 Hz, 1H), 8.18 (dd, J = 7.8, 1.2 Hz, 1H), 7.97 (d, J =7.9 Hz, 1H), 7.84 (d, J = 7.9 Hz, 1H), 7.76 (dd, J = 7.9, 1.3 Hz, 1H), 7.60(d, J = 7.9 Hz, 1H), 7.52 – 7.43 (m, 3H), 7.39 (td, J = 7.5, 1.3 Hz, 1H), 6.95 (d, J = 1.2 Hz, 1H), 4.15 (td, J = 7.4, 5.5 Hz, 1H), 2.94 (ddd, J =14.9, 5.2, 3.8 Hz, 1H), 2.72 (ddd, J = 14.8, 11.2, 5.9 Hz, 1H), 2.49 (dddd, J= 13.4, 7.8, 5.9, 3.8 Hz, 1H), 1.47 – 1.38 (m, 1H), 1.29 (d, J = 6.9 Hz, 3H). 13C NMR (101 MHz, CDCl3) δ 158.58, 158.31, 145.53, 140.98, 140.62, 139.75,139.26, 139.06, 135.58, 134.51, 134.15, 132.96, 132.66, 131.63, 126.38,124.18, 124.09, 122.94, 121.53, 121.17, 119.35, 118.89, 114.79, 112.50,112.43, 108.79, 55.76, 54.60, 34.24, 31.02, 28.99, 20.87.

[0069] Example 5

[0070] This embodiment relates to a method for preparing compound S5, including the following steps:

[0071] Under nitrogen protection, compound S2 (57 mg, 0.1 mmol) was dissolved in tetrahydrofuran (2.0 mL) and cooled to -78 °C. n-Butyllithium (1.6 M n-hexane solution, 0.25 mL, 0.4 mmol) was slowly added dropwise to the solution, and the mixture was stirred for 30 min. Dimethyl disulfide (0.4 mmol) was then added, the mixture was slowly brought to room temperature, and stirred overnight. The reaction was quenched with saturated ammonium chloride aqueous solution, extracted with dichloromethane, and the organic phase was washed successively with water and saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography (eluent: n-pentane / dichloromethane = 10:1) to give the yellow solid product photoswitcher S5 (31.9 mg, 0.063 mmol, 63%).

[0072] The analytical data of the product are as follows: 1H NMR (400 MHz, CDCl3) δ 8.11 – 8.03 (m, 2H), 7.85 (d, J = 1.6 Hz, 1H), 7.60 – 7.55 (m, 2H), 7.41 (d, J = 8.0 Hz, 1H), 7.37– 7.24 (m, 4H), 6.96 (dd, J = 7.9, 1.7 Hz, 1H), 6.38 (d, J = 1.7 Hz, 1H), 4.11 (h, J = 6.8 Hz, 1H), 2.76 (ddd, J = 14.3, 4.7, 3.2 Hz, 1H), 2.62 – 2.54(m, 1H), 2.53 (s, 3H), 1.35 (s, 3H), 1.23 (d, J = 6.9 Hz, 3H), 1.21 – 1.18 (m, 1H). 13 C NMR (101 MHz, CDCl3) δ 146.58, 140.92, 139.66, 138.54, 138.50,136.68, 136.65, 136.60, 135.64, 134.42, 132.01, 131.52, 126.96, 126.81,126.61, 124.61, 124.42, 124.35, 123.03, 121.87, 121.77, 121.24, 119.87,118.90, 34.59, 31.03, 29.09, 21.04, 17.20, 15.26.

[0073] Example 6

[0074] This embodiment relates to a method for preparing an S6 compound, comprising the following steps:

[0075] Under nitrogen protection, compound S2 (57 mg, 0.1 mmol) was dissolved in tetrahydrofuran (2.0 mL) and cooled to -78 °C. Butyllithium (1.6 M n-hexane solution, 0.25 mL, 0.4 mmol) was slowly added dropwise to the solution, and the mixture was stirred for 15 min. Anhydrous N,N-dimethylformamide (DMF) (0.4 mmol) was then added, and the mixture was brought back to room temperature and stirred for 1 h. The reaction was quenched with saturated ammonium chloride aqueous solution, extracted with ethyl acetate, and the organic phase was washed successively with water and saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography (eluent: n-pentane / ethyl acetate = 10:1) to give the yellow solid product photoswitcher S6 (21.2 mg, 0.045 mmol, 45%).

[0076] The analytical data of the product are as follows: 1 H NMR (400 MHz, CDCl3) δ 10.20 (s, 1H), 9.31 (s,1H), 8.61 (s, 1H), 8.28 (d, J = 8.0 Hz, 1H), 8.20 (d, J = 7.9 Hz, 1H), 8.11 –8.00 (m, 2H), 7.94 (d, J = 7.9 Hz, 1H), 7.79 (dd, J = 7.9, 1.4 Hz, 1H), 7.61 (d, J = 7.9 Hz, 1H), 7.54 – 7.43 (m, 2H), 7.38 (td, J = 7.6, 1.3 Hz, 1H),7.11 (d, J = 1.4 Hz, 1H), 4.34 (q, J = 6.9 Hz, 1H), 2.95 (dt, J = 14.6, 4.3Hz, 1H), 2.82 – 2.69 (m, 1H), 2.61 – 2.50 (m, 1H), 1.45 (dd, J = 12.1, 5.8Hz, 1H), 1.40 (d, J = 6.9 Hz, 3H). 13C NMR (101 MHz, CDCl3)δ 192.17, 191.99,150.50, 144.88, 143.15, 140.77, 139.56, 139.49, 139.34, 136.44, 136.23,135.58, 134.67, 130.78, 130.55, 130.28, 128.02, 127.59, 126.77, 126.20,124.60, 124.56, 122.84, 122.77, 121.59, 121.30, 120.80, 35.01, 30.53, 28.84, 20.93.

[0077] Example 7

[0078] This embodiment relates to a method for preparing an S7 compound, comprising the following steps:

[0079] Under nitrogen protection, compound S2 (57 mg, 0.1 mmol), 4-pyridineboronic acid (49.2 mg, 0.400 mmol), tetra(triphenylphosphine)palladium (11.6 mg, 10.00 μmol), and potassium carbonate (138.0 mg, 1.00 mmol) were dissolved in tetrahydrofuran (6 mL) and water (6 mL) and reacted at 75 °C for 24 h. The reaction mixture was then poured into water (20 mL) and extracted with ethyl acetate (3 × 10 mL). The organic phase was washed successively with water and saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography (eluent: n-pentane / ethyl acetate = 1:1) to give a yellow solid product S7 (32.9 mg, 0.058 mmol, 58%).

[0080] The analytical data of the product are as follows: 1H NMR (400 MHz, CDCl3) δ 8.67 (d, J = 5.3 Hz, 2H), 8.26 (d, J = 1.6 Hz, 1H), 8.23 ​​– 8.09 (m, 4H), 7.88 (d, J = 7.9 Hz, 1H), 7.73 (d, J = 7.8 Hz, 1H), 7.66 (dd, J = 7.8, 1.5 Hz, 1H), 7.62 – 7.54 (m,3H), 7.47 – 7.41 (m, 1H), 7.39 – 7.30 (m, 3H), 6.77 (d, J = 1.5 Hz, 1H), 6.53– 6.46 (m, 2H), 4.25 (p, J = 7.0 Hz, 1H), 2.78 (dt, J = 14.4, 3.8 Hz, 1H), 2.61 – 2.42 (m, 2H), 1.37 (d, J = 6.9 Hz, 3H), 1.33 – 1.26 (m, 1H). 13 C NMR(101 MHz, CDCl3) δ 150.51, 149.70, 149.05, 148.57, 147.46, 141.27, 141.06,140.98, 139.50, 139.42, 139.27, 138.81, 137.56, 136.99, 135.64, 134.44,131.79, 131.24, 126.95, 126.89, 126.35, 124.76, 124.52, 124.27, 123.81,123.04, 122.11, 121.80, 121.32, 121.26, 120.77, 119.90, 34.93, 31.06, 29.16, 21.10.

[0081] Example 8

[0082] This embodiment relates to a method for preparing an S8 compound, comprising the following steps:

[0083] Under argon protection, a 1.0 mL solution of compound S7 in acetonitrile was added to a two-necked flask, followed by methyl iodide (CH3I, 56.8 mg, 0.4 mmol). The mixture was heated at 90 °C for 16 h, then cooled to room temperature. The solvent was removed under reduced pressure to obtain the crude product, which was purified by recrystallization from an acetonitrile / ethyl acetate co-solvent system to give the yellow solid product S8 (72.4 mg, 0.085 mmol, 85%).

[0084] The analytical data of the product are as follows: 1 H NMR (400 MHz, DMSO-d6 ) δ 9.08 (d, J = 6.6 Hz,2H), 8.67 (t, J = 6.9 Hz, 4H), 8.53 (d, J = 8.5 Hz, 2H), 8.45 (t, J = 8.3 Hz,2H), 8.30 (d, J = 8.1 Hz, 1H), 8.23 ​​(dd, J = 8.0, 1.5 Hz, 1H), 7.93 (dd, J =8.0, 1.7 Hz, 1H), 7.81 (d, J = 8.0 Hz, 1H), 7.67 (d, J = 8.0 Hz, 1H), 7.54(t, J = 7.6 Hz, 1H), 7.43 (t, J = 7.6 Hz, 1H), 7.34 (d, J = 6.5 Hz, 2H), 6.95(d, J = 1.7 Hz, 1H), 4.48 – 4.42 (m, 1H), 4.40 (s, 3H), 4.16 (s, 3H), 2.98(dt, J = 14.7, 4.1 Hz, 1H), 2.71 – 2.62 (m, 1H), 2.60 – 2.53 (m, 1H), 1.33 (d, J = 6.8 Hz, 3H). 13 C NMR (101 MHz, DMSO-d6) δ 155.30, 154.62, 150.43,146.09, 145.80, 142.08, 141.86, 141.31, 140.05, 139.19, 139.14, 138.49,135.34, 134.68, 134.34, 133.25, 130.92, 130.40, 128.99, 128.46, 127.58,125.54, 125.17, 123.57, 123.47, 123.32, 123.25, 122.85, 122.40, 47.66, 47.42, 34.67, 30.63, 28.57, 21.05.

[0085] Example 9

[0086] This embodiment relates to a method for preparing an S9 compound, comprising the following steps:

[0087] Under nitrogen protection, compound S2 (57 mg, 0.1 mmol), 4-n-pentylphenylboronic acid (76.8 mg, 0.400 mmol), tetrakis(triphenylphosphine)palladium (11.6 mg, 10.00 μmol), and potassium carbonate (138.0 mg, 1.00 mmol) were dissolved in tetrahydrofuran (6 mL) and water (6 mL) and reacted at 75 °C for 24 h. The reaction mixture was then poured into water (20 mL) and extracted with ethyl acetate (3 × 10 mL). The organic phase was washed successively with water and saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography (eluent: n-pentane) to give a yellow solid product S9 (63.5 mg, 0.09 mmol, 90%).

[0088] The analytical data of the product are as follows: 1 H NMR (400 MHz, CDCl3) δ 8.30 – 8.16 (m, 3H),7.85 (d, J = 7.9 Hz, 1H), 7.76 – 7.60 (m, 5H), 7.54 – 7.45 (m, 1H), 7.43 –7.30 (m, 5H), 6.85 – 6.74 (m, 3H), 6.61 – 6.54 (m, 2H), 4.33 (q, J = 7.0 Hz,1H), 2.81 (dt, J = 14.4, 3.9 Hz, 1H), 2.74 – 2.57 (m, 3H), 2.54 – 2.42 (m,3H), 1.69 (q, J = 7.6 Hz, 2H), 1.50 (q, J = 7.5 Hz, 2H), 1.46 – 1.20 (m,15H), 0.91 (dt, J = 20.0, 7.1 Hz, 6H). 13C NMR (101 MHz, CDCl3) δ 145.82,142.27, 141.57, 141.19, 141.07, 140.28, 139.89, 139.83, 139.63, 139.49,138.98, 138.77, 138.59, 138.31, 135.90, 134.42, 132.71, 131.84, 129.17,128.45, 127.24, 127.00, 126.65, 126.35, 124.43, 124.37, 123.74, 123.15,121.79, 121.22, 120.10, 119.25, 35.83, 35.60, 34.66, 31.80, 31.73, 31.43, 31.26, 31.23, 29.22, 22.78, 22.70, 21.21, 14.25, 14.22.

[0089] Example 10

[0090] This embodiment relates to a method for preparing an S10 compound, comprising the following steps:

[0091] Under nitrogen protection, compound S2 (57 mg, 0.1 mmol), 4-n-cyanobenzoic acid (58.8 mg, 0.400 mmol), tetrakis(triphenylphosphine)palladium (11.6 mg, 10.00 μmol), and potassium carbonate (138.0 mg, 1.00 mmol) were dissolved in tetrahydrofuran (6 mL) and water (6 mL) and reacted at 75 °C for 24 h. The reaction mixture was then poured into water (20 mL) and extracted with ethyl acetate (3 × 10 mL). The organic phase was washed successively with water and saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography (eluent: n-pentane / ethyl acetate = 5:1) to give a yellow solid product S10 (54.2 mg, 0.088 mmol, 88%).

[0092] The analytical data of the product are as follows: 1H NMR (400 MHz, CDCl3) δ 8.25 (dd, J = 22.8, 7.2Hz, 3H), 7.94 (d, J = 7.9 Hz, 1H), 7.80 (d, J = 14.5 Hz, 5H), 7.69 (dd, J =7.6, 6.2 Hz, 2H), 7.54 (t, J = 7.6 Hz, 1H), 7.48 – 7.35 (m, 3H), 7.25 – 7.19(m, 2H), 6.76 (d, J = 1.6 Hz, 1H), 6.73 – 6.63 (m, 2H), 4.30 (q, J = 7.1 Hz,1H), 2.90 – 2.80 (m, 1H), 2.71 – 2.46 (m, 2H), 1.43 (d, J = 6.9 Hz, 3H), 1.37 – 1.31 (m, 1H).

[0093] Example 11

[0094] This embodiment relates to a method for preparing an S11 compound, comprising the following steps:

[0095] Compound S1 (41.4 mg, 0.1 mmol) was mixed with m-chloroperoxybenzoic acid (m-CPBA, 0.17 mmol, 80%) and stirred at -20 °C for 4 h. The reaction mixture was poured into a saturated aqueous sodium sulfite solution and extracted with dichloromethane. The combined organic phases were dried over anhydrous sodium sulfate, filtered, and concentrated by rotary evaporation. The residue was purified by silica gel column chromatography (eluent: n-pentane / dichloromethane = 2:1) to give a yellow solid product S11 (41.3 mg, 0.096 mmol, 96%).

[0096] The analytical data of the product are as follows: 1H NMR (400 MHz, CDCl3) δ 8.02 (dd, J = 6.7, 1.9Hz, 1H), 7.83 – 7.66 (m, 5H), 7.58 – 7.50 (m, 2H), 7.44 – 7.33 (m, 3H), 7.16(td, J = 7.4, 1.1 Hz, 1H), 6.77 (td, J = 7.6, 7.2, 1.2 Hz, 1H), 6.67 (d, J =8.0 Hz, 1H), 4.19 (p, J = 7.1 Hz, 1H), 2.74 (ddd, J = 13.6, 4.2, 2.6 Hz, 1H),2.60 – 2.42 (m, 2H), 1.42 (d, J = 6.9 Hz, 3H), 1.26 – 1.15 (m, 1H). 13 C NMR(101 MHz, CDCl3) δ 146.03, 145.93, 144.05, 143.07, 141.09, 140.37, 138.39,137.97, 137.70, 137.49, 136.78, 133.21, 132.49, 131.30, 129.33, 128.19,127.82, 127.72, 127.49, 126.93, 125.93, 123.22, 121.97, 121.77, 119.82,119.69, 34.22, 31.66, 29.31, 21.08.

[0097] Furthermore, S1 can be prepared via S11, specifically as follows:

[0098] In a 10 mL Schlenk tube, compound S11 (43.0 mg, 0.1 mmol), B2(OH)4 (72 mg, 0.2 mmol), and toluene (2 mL) were added. The mixture was stirred at 100 °C for 8 h under air. After cooling, the reaction mixture was poured into water and extracted three times with ethyl acetate. The organic layer was washed with brine, dried over anhydrous sodium sulfate, concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (eluent: n-pentane) to give a yellow solid product S1 (39.6 mg, 0.096 mmol, 96%).

[0099] Example 12

[0100] This embodiment relates to a method for preparing an S12 compound, comprising the following steps:

[0101] Compound S1 (41.4 mg, 0.1 mmol) was mixed with m-chloroperoxybenzoic acid (m-CPBA, 0.3 mmol, 80%) and stirred at room temperature for 12 h. The reaction mixture was poured into a saturated aqueous sodium sulfite solution and extracted with dichloromethane. The extracts were combined, dried over anhydrous sodium sulfate, filtered, and the solvent was evaporated. The residue was purified by silica gel column chromatography (eluent: n-pentane / dichloromethane = 4:1) to give a yellow solid product S12 (43.7 mg, 0.098 mmol, 98%).

[0102] The analytical data of the product are as follows: 1 H NMR (400 MHz, CDCl3) δ 7.99 (d, J = 7.5 Hz,1H), 7.82 (t, J = 7.4 Hz, 2H), 7.75 (dd, J = 7.2, 1.5 Hz, 1H), 7.67 – 7.55(m, 4H), 7.46 – 7.32 (m, 3H), 7.16 (td, J = 7.5, 1.0 Hz, 1H), 6.84 (td, J =7.7, 1.2 Hz, 1H), 6.63 (d, J = 8.0 Hz, 1H), 4.27 – 4.16 (m, 1H), 2.76 – 2.65(m, 1H), 2.55 – 2.40 (m, 2H), 1.41 (d, J = 6.9 Hz, 3H), 1.22 – 1.09 (m, 1H). 13 C NMR (101 MHz, CDCl3) δ 145.72, 141.64, 139.80, 139.28, 139.18, 138.42,137.96, 136.71, 136.36, 135.77, 133.61, 131.76, 131.45, 130.88, 130.03,128.38, 127.71, 127.14, 126.77, 125.68, 123.92, 122.24, 121.47, 121.18,119.99, 119.35, 34.56, 31.56, 29.37, 21.61.

[0103] Example 13

[0104] This embodiment relates to a method for preparing an S13 compound, comprising the following steps:

[0105] Under argon protection, compound S1 (41.4 mg, 0.1 mmol), iodobenzene diacetate (80.5 mg, 0.25 mmol), and ammonium carbamate (15.6 mg, 0.20 mmol) were added sequentially to a two-necked flask. MeOH (methanol) / DCM (dichloromethane) (V / V, 1 / 1) was added, and the reaction mixture was stirred at 25 °C for 12 h. Subsequently, the solvent was removed under reduced pressure. The crude product was purified by rapid silica gel column chromatography (eluent: n-pentane / ethyl acetate = 4:1) to give the yellow solid product sulfoxide imine S13 (17.8 mg, 0.04 mmol, 40%).

[0106] The analytical data of the product are as follows: 1 H NMR (400 MHz, CDCl3) δ 8.07 – 7.98 (m, 1H),7.89 – 7.73 (m, 4H), 7.68 (d, J = 7.6 Hz, 1H), 7.64 – 7.51 (m, 2H), 7.48 –7.35 (m, 3H), 7.24 – 7.16 (m, 1H), 6.94 – 6.85 (m, 1H), 6.73 (d, J = 8.0 Hz,1H), 4.23 (dt, J = 8.6, 6.7 Hz, 1H), 2.71 (dq, J = 12.8, 3.3, 2.7 Hz, 1H),2.55 – 2.42 (m, 2H), 2.38 – 2.14 (s, 1H), 1.39 (d, J = 7.0 Hz, 3H), 1.15 (dtd, J = 13.6, 9.3, 8.1, 4.9 Hz, 1H). 13 C NMR (101 MHz, CDCl3) δ 145.13,141.76, 140.88, 139.80, 139.73, 139.67, 137.54, 137.30, 134.61, 133.75,132.99, 132.15, 130.33, 130.27, 129.78, 128.37, 128.33, 127.52, 127.34,125.64, 124.15, 122.29, 121.71, 120.90, 119.89, 119.52, 34.72, 31.26, 29.27, 21.17.

[0107] Example 14

[0108] This embodiment designs a method for preparing compound S14, including the following steps:

[0109] In a two-necked flask, compound S13 (44.5 mg, 0.1 mmol), cesium carbonate (45.6 mg, 0.14 mmol), palladium acetate (1.2 mg, 0.005 mmol), and binaphthalene diphenylphosphine (BINAP, 4.0 mg, 0.0075 mmol) were added sequentially. The mixture was evacuated three times to establish a nitrogen atmosphere. Under nitrogen protection, ultra-dry toluene (1.0 mL) and bromobenzene (17.3 mg, 0.11 mmol) were added. The reaction mixture was stirred at 110 °C for 24 h, followed by solvent removal under reduced pressure. The crude product was purified by rapid silica gel column chromatography (eluent: n-pentane / ethyl acetate = 8:1) to give a yellow solid product S14 (43.2 mg, 0.083 mmol, 83%).

[0110] The analytical data of the product are as follows: 1 H NMR (400 MHz, CDCl3) δ 7.83 – 7.66 (m, 4H), 7.58 – 7.41 (m, 3H), 7.39 – 7.29 (m, 2H), 7.21 (dd, J = 5.7, 3.1 Hz, 2H), 7.01 (td, J = 7.5, 1.0 Hz, 1H), 6.73 (td, J = 7.6, 1.2 Hz, 1H), 6.49 – 6.40 (m, 3H), 6.39 – 6.29 (m, 2H), 6.25 (tt, J = 7.2, 1.3 Hz, 1H), 4.09 (dt, J =8.7, 6.7 Hz, 1H), 2.54 (ddd, J = 13.8, 3.8, 1.9 Hz, 1H), 2.36 – 2.21 (m, 2H), 1.38 (d, J = 6.9 Hz, 3H), 1.06 – 0.95 (m, 1H). 13C NMR (101 MHz, CDCl3) δ146.02, 143.00, 141.27, 141.24, 140.02, 139.77, 138.87, 137.85, 136.63,134.35, 133.18, 131.91, 130.58, 130.41, 129.92, 127.73, 127.60, 127.08,126.73, 126.50, 125.34, 123.77, 122.67, 122.59, 121.22, 121.19, 120.93,119.57, 118.65, 34.89, 31.73, 29.65, 21.27.

[0111] The mechanism of action of the chiral photoswitch with a dibenzothiophene framework in this invention is as follows: Figure 1 As shown, the stable isomer reaches a metastable state upon irradiation with 340 nm wavelength light, and returns to the stable isomer upon irradiation with 450 nm wavelength light. Furthermore, the photoswitch can further oxidize to sulfoxide or sulfone. The switching light and redox stimulation do not interfere with each other, and six stable chiral states can be obtained through orthogonal modulation.

[0112] Test case

[0113] To test the photochemical isomerization reaction of the novel photoswitches of this invention, ultraviolet (UV) light was used to test photoswitches S1, S11, S12, and S13. Molecular photoswitches S1, S11, and S12 were dissolved in DCM solvent, and S13 was dissolved in THF to prepare a solution with a concentration of 2 × 10⁻⁵ mol / L for testing. (Reference) Figure 2-5 The photoswitch transforms from a stable isomer to a metastable isomer under 340 nm or 365 nm illumination, and then recombines back to the stable isomer under 420 nm, 450 nm, or 455 nm illumination. The black solid line represents the original spectrum of the stable isomer, and the gray solid line represents the spectrum after illumination from 340 nm / 365 nm to the photostable state (PSS). 340 / PSS 365 The spectrum of light is shown, with the black dashed lines representing the light irradiated at 420 nm / 450 nm / 455 nm to the steady state (PSS). 420 / PSS 455 The spectrum of the molecular optical switch S1 was observed. Furthermore, fatigue resistance testing was performed on the S1 molecular optical switch; it maintained good fatigue resistance even after ten light cycles. Figure 6 As shown.

[0114] The proton NMR spectra of the novel optical switches S1-S3 were analyzed (400 MHz, 298 K, deuterated chloroform, 5 mM). Reference Figure 7-9The figure shows the ratio of metastable isomers to stable isomers. It can be seen that the stable isomer reaches the metastable isomer after being illuminated by 340 nm or 365 nm light, and then reaches the photostable state and returns to the stable isomer after being illuminated by 455 nm light.

[0115] A novel chiral photoswitcher S2 with a dibenzothiophene skeleton and a photoresponsive structure was subjected to circular dichroism spectroscopy (test conditions: 298 K, dichloromethane solvent, concentration 2.5*10⁻⁵ mol / L). Reference Figure 10 The black solid line represents the original spectrum of the stable isomer, and the gray solid line represents the spectrum after irradiation with 365 nm light to the steady-state optical spectrum (PSS). 365 The spectrum of light is shown, with the black dashed line representing the light irradiated at 455 nm to the steady state (PSS). 455 The spectrum of the chiral optical switch S2 shows that it possesses a completely reversible photochirality reversal property.

[0116] Application Example 1

[0117] The HTP (Helical Twisting Power) value of molecular switch S9 and its change under illumination were determined using the Grandjean-Cano wedge box method.

[0118] (1) The glass substrate was ultrasonically cleaned with acetone and isopropanol in sequence, and then dried with nitrogen. The glass surface was then activated with ozone for 20 min to obtain a thoroughly cleaned glass substrate.

[0119] (2) A 5 wt% PVA (polyvinyl alcohol) aqueous solution was spin-coated onto a clean glass substrate at 2000 rpm for 60 s. The substrate was then heated on a hot table at 100 ℃ for 1 h to allow the moisture to evaporate completely. Next, the surface of the glass substrate was rubbed with a velvet cloth in the same direction to induce orientation.

[0120] (3) Two UV-cured spacers of different sizes are added to both ends of the two treated glass substrates and bonded together in the same direction to form a wedge-shaped box with an opening angle of θ and tan θ=0.0079.

[0121] HTP Testing

[0122] (1) The enantiomers of molecular Mach-S9 and low molecular weight liquid crystal E7 were dissolved in dichloromethane (DCM) and stirred overnight at 60 °C to fully evaporate the solvent DCM, resulting in a homogeneous liquid crystal mixture. To ensure the accuracy of the test results, liquid crystal samples with chiral dopant concentrations of 0.5 wt%, 1.0 wt%, and 1.5 wt% were prepared respectively.

[0123] (2) At 70 °C, liquid crystal mixtures of different concentrations were injected into a wedge-shaped liquid crystal cell by capillary action, and then slowly cooled to room temperature to form a stable cholesteric liquid crystal (CLC) structure.

[0124] (3) Observe the Grandjean-Cano misalignment lines in the cholesteric liquid crystal under a polarizing microscope (POM) and measure the distance L between two adjacent misalignment lines, referring to... Figure 11 The pitch p of the cholesteric liquid crystal is calculated using the following formula: p = 2Ltanθ.

[0125] (4) Further based on the definition of Helical Twist Capability (HTP): Where c represents the mass concentration of the chiral molecular motor. By plotting the relationship between 1 / p and concentration c, and performing linear fitting, the HTP value of the sample can be obtained. Figure 12 The results quantitatively demonstrated the reversible control of light on the liquid crystal spiral structure.

[0126] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

Claims

1. A chiral optical switch containing a dibenzothiophene framework, characterized in that, It has one of the structures shown in equations S1-S14: 。 2. A method for preparing a chiral photoswitch containing a dibenzothiophene framework as described in claim 1, characterized in that, Includes the following steps: The compound of formula 3 was mixed with Lawson's reagent and reacted at 100-120 °C to obtain an intermediate; then the intermediate was reacted with 9-diazo-9H-fluorene, 2,7-dibromo-9-diazo-9H-fluorene or 2,7-dimethoxy-9-diazo-9H-fluorene in the presence of hexamethylphosphoric triamine to obtain a chiral photoswitch with a dibenzothiophene skeleton containing one of formulas S1-S3; The structural formula of compound 3 is as follows: 。 3. The method for preparing a chiral photoswitch containing a dibenzothiophene framework as described in claim 2, characterized in that, The preparation method of compound 3 includes the following steps: (1) 4-Bromodibenzothiophene and cyclobutanone react in the presence of n-butyllithium to give compound of formula 1; (2) The compound of Formula 1 is mixed with cerium ammonium nitrate and reacted to obtain the compound of Formula 2; (3) Mix diisopropylamine, n-butyllithium, hexamethylphosphoric triamine, compound of formula 2 and potassium iodide, and react to obtain compound of formula 3; Intermediates 1-2 each have the structure shown in Equation 1-2: 。 4. The method for preparing a chiral photoswitch containing a dibenzothiophene framework as described in claim 3, characterized in that, The reaction temperatures for steps (1) and (2) are independently selected from -5 to 5℃; the reaction temperature for step (3) is -80 to -70℃.

5. A method for preparing a chiral photoswitch containing a dibenzothiophene framework as described in claim 1, characterized in that, Includes the following steps: A chiral photoswitch containing a dibenzothiophene skeleton is prepared by mixing the compound of formula S2 with zinc cyanide, dimethyl disulfide, N,-N-dimethylformamide, 4-pyridineboronic acid, 4-n-pentylphenylboronic acid or 4-n-cyanophenylboronic acid through a substitution reaction.

6. A method for preparing a chiral photoswitch containing a dibenzothiophene framework as described in claim 1, characterized in that, Includes the following steps: The S7 compound was mixed with iodomethane to produce the S8 chiral photoswitch containing a dibenzothiophene skeleton.

7. A method for preparing a chiral photoswitch containing a dibenzothiophene framework as described in claim 1, characterized in that, Includes the following steps: The compound of formula S1 is mixed with m-chloroperoxybenzoic acid and subjected to an oxidation reaction to obtain a chiral photoswitch of formula S11 or S12 containing a dibenzothiophene skeleton.

8. A method for preparing a chiral photoswitch containing a dibenzothiophene framework as described in claim 1, characterized in that, Includes the following steps: The S1 compound was mixed with diacetic acid iodobenzene and ammonium carbamate for a nucleophilic reaction to obtain the S13 chiral photoswitch containing a dibenzothiophene skeleton.

9. A method for preparing a chiral photoswitch containing a dibenzothiophene framework as described in claim 1, characterized in that, Includes the following steps: The compound of formula S13 was coupled with cesium carbonate and bromobenzene in the presence of palladium acetate and binaphthalene diphenylphosphine to obtain a chiral photoswitch of formula S14 containing a dibenzothiophene skeleton.

10. The application of the dibenzothiophene-containing chiral optical switch of claim 1 in the field of optics.

Images