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CN-122010853-A - Supermolecule liquid crystal compound and preparation method thereof

CN122010853ACN 122010853 ACN122010853 ACN 122010853ACN-122010853-A

Abstract

The invention discloses a supermolecule liquid crystal compound and a preparation method thereof. The structural formula is as follows: The liquid crystal performance and the light response property of the compound are mainly tested by POM, UV and other methods. The compound can form a smectic phase (SmA), and the photo-response property of the compound is researched by ultraviolet spectrum, and the result shows that the compound has a smectic phase (SmA), has good photo-response behavior and reversible photophysical property, and is expected to be used for a photoelectric molecular switch.

Inventors

  • TAN XIAOPING

Assignees

  • 长江师范学院

Dates

Publication Date
20260512
Application Date
20260203

Claims (10)

  1. 1. A novel liquid crystal supermolecular compound is characterized by having a structural formula: 。
  2. 2. A preparation method of a novel liquid crystal supermolecular compound as claimed in claim 1 is characterized in that p-nitrophenol is used as a starting material, intermediate 1 is obtained by reaction under alkaline conditions, methyl gallate and bromododecyl are reacted to obtain intermediate 2, intermediate 2 is reduced to obtain intermediate 3, intermediate 3 is chlorinated to obtain intermediate 4, intermediate 1 and intermediate 4 are reacted to obtain intermediate 5, intermediate 5 and propargyl bromide are reacted to obtain intermediate 6, ‌, 4-diethyl bromide and (CH 2 O) n ) are reacted to obtain intermediate 7, intermediate 7 and sodium azide are reacted to obtain intermediate 8, and intermediate 8 and intermediate 6 are reacted to obtain a target product; The reaction formula is: 。
  3. 3. The process for preparing a novel liquid crystalline supramolecular compound as claimed in claim 2, wherein the synthesis of intermediate 1 is carried out by adding KOH and water into a reaction vessel, stirring under ice bath condition until cooling to room temperature, adding p-nitrophenol, starting the reaction at 120 ℃, heating to 200 ℃ at 5 ℃ per time until the temperature reaches 120 ℃, reacting to completion, cooling to room temperature after the reaction is completed, adding water into a reaction vessel, adjusting pH value of the solution to 3-4 with dilute HCl, extracting with ethyl acetate, drying the organic layer, evaporating under reduced pressure to obtain a yellow crude product, separating and purifying the crude product with column chromatography to obtain intermediate 1.
  4. 4. A preparation method of the novel liquid crystal supermolecular compound as claimed in claim 3, wherein the intermediate 2 is synthesized by adding methyl gallate and K 2 CO 3 into a reaction vessel, adding ‌ N, N-dimethylformamide as a solvent, carrying out reflux reaction, slowly adding bromododecyl into the reaction solution, continuously reacting until the reaction is complete, cooling the reaction solution to room temperature, adding water and ethyl acetate, extracting to obtain an upper organic layer, washing the organic layer with saturated NaCl solution, drying with anhydrous sodium sulfate, evaporating the solvent, and purifying by adopting a column chromatography method to obtain the intermediate 2.
  5. 5. The method for preparing a novel liquid crystal supramolecular compound as claimed in claim 4, wherein the synthesis of intermediate 3 is carried out by adding THF and intermediate 2 into flask, adding LiAlH 4 under ice bath condition, reacting at room temperature until reaction is complete, slowly dropping water into reaction liquid under ice bath condition, observing generation of a large amount of bubbles and white solid, adding dilute HCl until no bubbles are generated, extracting organic layer with dichloromethane, drying anhydrous sodium sulfate, and evaporating solvent to obtain intermediate 3.
  6. 6. The method for preparing a novel liquid crystal supramolecular compound as claimed in claim 5, wherein the synthesis of intermediate 4 is carried out by adding THF, DMF and intermediate 3 into a reaction vessel, stirring, dropping thionyl chloride ‌ and reacting at room temperature until reaction is complete, distilling under reduced pressure to remove solvent to obtain intermediate 4.
  7. 7. The method for preparing a novel liquid crystal supramolecular compound as claimed in claim 6, wherein the intermediate 5 is synthesized by adding the intermediate 4, the intermediate 1 and the K 2 CO 3 into a reaction vessel, then adding ‌ DMF until the mixture is completely dissolved, refluxing until the reaction is finished, cooling to room temperature, adding water into ‌, suction filtering, dissolving the obtained product with ethyl acetate, drying ‌ anhydrous sodium sulfate, evaporating under reduced pressure, and purifying by adopting ‌ column chromatography to obtain the intermediate 5.
  8. 8. The method for preparing a novel liquid crystal supramolecular compound as claimed in claim 7, wherein the intermediate 6 is synthesized by adding potassium carbonate, intermediate 5, solvent CH 3 CN and propargyl bromide ‌ ‌ into a reaction vessel, refluxing until the reaction is completed, cooling the reaction liquid to room temperature, evaporating the solvent under reduced pressure, extracting the organic layer with water and dichloromethane, washing ‌ ‌ with NaOH aqueous solution and saturated saline solution, drying, evaporating ‌ of the dried solvent under reduced pressure, separating and purifying ‌ crude product by column chromatography to obtain intermediate 6.
  9. 9. The process for preparing a novel liquid crystal supramolecular compound as claimed in claim 8, wherein the intermediate 7 is prepared by adding (CH 2 O) n , ‌, 4-dioxyethyl bromide) into a reaction vessel, adding chloroform for dissolving, adding dropwise boron trifluoride diethyl ether ‌, reacting at room temperature until the reaction is finished, adding water, ‌ CH 2 Cl 2 for extraction, drying the organic layer with anhydrous sodium sulfate, evaporating the solvent under reduced pressure, and separating and purifying by column chromatography to obtain the intermediate 7.
  10. 10. A process for preparing the novel liquid crystal supermolecular compound as claimed in claim 9, wherein the intermediate 8 is prepared by adding ‌ ‌ to the reaction vessel to dissolve intermediate 7, naN 3 ‌, KI and DMF, refluxing to react completely, cooling to room temperature, adding water, extracting ‌ with CH 2 Cl 2 , washing ‌ organic layer with saturated sodium chloride, drying with anhydrous sodium sulfate, evaporating solvent to obtain intermediate 8, wherein the intermediate 9 is prepared by adding cuprous iodide, intermediate 6 and intermediate 8, ‌ to the reaction vessel to dissolve solid compound, protecting N 2 , finishing the reaction at ‌ ℃ and cooling to room temperature, adding water ‌, extracting ‌ with CHCl 3 , washing the organic layer with saturated brine, drying with anhydrous sodium sulfate, evaporating solvent, separating and purifying by column chromatography.

Description

Supermolecule liquid crystal compound and preparation method thereof Technical Field The invention relates to the technical field of new materials, in particular to a supermolecule liquid crystal compound and a preparation method thereof. Background Liquid crystals are a soft substance between solids and liquids that not only maintains the anisotropy of solids, but also has the continuity and flowability of liquids. Since it was found, liquid crystal materials have been widely used in various fields such as home appliances, industrial equipment, GPS navigator, etc., so that it can be said that liquid crystals are ubiquitous. Azobenzene liquid crystal molecules based on column [5] arene are very attractive as a liquid crystal photoactive material. Typical polymeric photoactive materials have an indeterminate composition, simple azobenzene derivatives undergo severe hydrogen polymerization, and column [5] arene azobenzene liquid crystal molecules just overcome these drawbacks. The tubular column [5] arene macrocycles provide enough free space for azobenzene to achieve reversible photoisomerization, so they exhibit excellent photoinitiated modulating surface free energy, wettability, and photoinduced orientation. So far, liquid crystals can be classified according to various criteria. The liquid crystals can be classified into banana-shaped, rod-shaped and disk-shaped liquid crystals due to different molecular shapes, liquid crystal polymers and small-molecule liquid crystals due to different molecular mass sizes, and lyotropic liquid crystals and thermotropic liquid crystals due to different composition conditions and components. The liquid crystal property of thermotropic liquid crystal is changed along with the temperature, and the property of the thermotropic liquid crystal is changed under different solvents and concentrations, and the thermotropic liquid crystal is a mixture. Thermotropic liquid crystals can be divided into three main categories, nematic, cholesteric and smectic phases, with smectic phase a and smectic phase C being the most common of the smectic phases. Smectic phase liquid crystal molecules are uniformly aligned in layers with their major axes parallel to each other within the layer, the direction of the SmA phase liquid crystal compound is perpendicular to the layer plane, but the SmC phase liquid crystal axis is tilted from the layer plane. The molecule can move between back and forth and left and right, but it cannot move between the upper and lower layers. Since the smectic phase is ordered, it generally occurs at low temperatures. Molecules in the nematic phase have their principal axes maintained substantially parallel, but their centroid positions are more disordered than those in the smectic phase, and therefore have considerable mobility. Most cholesteric liquid crystal molecules are derivatives of cholesterol, have a spiral structure and have high optical activity. In practice, such molecules are a particular state of the nematic phase. In addition, there are blue phases, columnar phases, and three-dimensional cubes. The liquid crystal material obtained by a series of methods is particularly important for the current society, a series of liquid crystal molecules are designed and synthesized, and the performance of the liquid crystal molecules is researched, so that the liquid crystal material is one of hot spots in the field of researching liquid crystals at present. Disclosure of Invention In view of the above-mentioned problems, a first object of the present invention is to provide a liquid crystal molecular compound, and a second object is to provide a method for preparing the compound. The compound has smectic phase (SmA) and good photoresponsive behavior. In order to achieve the first object, the present invention provides a novel liquid crystal supermolecular compound, which has the structural formula: 。 The second aim of the invention is realized by the preparation method of the novel liquid crystal supermolecular compound, which is characterized in that p-nitrophenol is used as a starting material, intermediate 1 is obtained by reaction under alkaline conditions, intermediate 2 is obtained by reaction of methyl gallate and bromododecyl, intermediate 3 is obtained by reduction of intermediate 2, intermediate 4 is obtained by chlorination of intermediate 3, intermediate 5 is obtained by reaction of intermediate 1 and intermediate 4, intermediate 5 is reacted with propargyl bromide to obtain intermediate 6, ‌, 4-dioxyethyl bromide is reacted with (CH 2O)n to generate intermediate 7, intermediate 7 is reacted with sodium azide to generate intermediate 8, and intermediate 8 is reacted with intermediate 6 to generate a target product; The reaction formula is: 。 In the scheme, the intermediate 1 is synthesized by adding KOH and water into a reaction container, stirring under ice bath condition until cooling to room temperature, adding p-nitrophenol, starting the reaction at