阅读说明：本技术 一种A-π-D-π-A结构双光子聚合引发剂及其制备方法 (A-pi-D-pi-A structure two-photon polymerization initiator and preparation method thereof ) 是由 张帅 李尚耕 徐嘉靖 尹强 万翔宇 朱方华 李娃 王宇光 于 2019-10-28 设计创作，主要内容包括：本发明公开一种A-π-D-π-A结构双光子聚合引发剂及其制备方法,包括：包括如下步骤：步骤一、对原料吩噻嗪和3,6-二溴-9H-咔唑通过取代反应加入十二烷基进行保护；对吩噻嗪进行溴代反应,引入对位溴；步骤二、对步骤一所得结果进行Sonogashira偶联反应,引入炔羟基团；步骤三、对步骤二所得产物,进行去保护,去除羟基；步骤四、对步骤三所得结果进行Sonogashira偶联反应,引入功能吸电子基团。研究了本发明的引发剂的光学性质和双光子聚合性能,结果表明,最佳性能的引发剂在50mw的激光功率下,聚合过程中扫描速度可达2000μm/s。(The invention discloses a two-photon polymerization initiator with an A-pi-D-pi-A structure and a preparation method thereof, wherein the preparation method comprises the following steps: the method comprises the following steps: firstly, adding dodecyl into phenothiazine and 3, 6-dibromo-9H-carbazole serving as raw materials through a substitution reaction for protection; carrying out bromination reaction on phenothiazine, and introducing para-bromine; step two, performing Sonogashira coupling reaction on the result obtained in the step one, and introducing acetylene hydroxyl groups; step three, performing deprotection on the product obtained in the step two to remove hydroxyl; and step four, performing Sonogashira coupling reaction on the result obtained in the step three, and introducing a functional electron-withdrawing group. The optical property and the two-photon polymerization performance of the initiator are researched, and the result shows that the initiator with the best performance can reach 2000 mu m/s at the laser power of 50mw in the polymerization process.)

1. A two-photon polymerization initiator with an A-pi-D-pi-A structure is characterized in that the initiator is an A-pi-D-pi-A structure formed by connecting a benzophenone or fluorenone group through a carbon-carbon triple bond as a conjugate bridge, and the molecular structural formula of the initiator is as follows:

or

Or

Or

2. A method for preparing the a-pi-D-pi-a structure two-photon polymerization initiator according to claim 1, comprising the steps of:

firstly, adding dodecyl into phenothiazine and 3, 6-dibromo-9H-carbazole serving as raw materials through a substitution reaction for protection; carrying out bromination reaction on phenothiazine, and introducing para-bromine;

step two, performing Sonogashira coupling reaction on the result obtained in the step one, and introducing acetylene hydroxyl groups;

step three, performing deprotection on the product obtained in the step two to remove hydroxyl;

and step four, performing Sonogashira coupling reaction on the result obtained in the step three, and introducing a functional electron-withdrawing group.

3. The method for preparing the a-pi-D-pi-a structure two-photon polymerization initiator according to claim 2, wherein the process of the first step is: slowly adding NaH stored in mineral oil into a phenothiazine-containing DMF solution which is cooled to 0-5 ℃, and slowly adding 1-bromododecane after 10-30 minutes; stirring the obtained solution at 0-5 ℃ overnight, and slowly adding deionized water; after stirring for half an hour, extraction with ethyl acetate and then purification by column chromatography using a 40: 1, petroleum ether and ethyl acetate are used as eluent to obtain 10-dodecyl-10H-phenothiazine which is light yellow oily matter;

slowly adding NBS into a solution which is cooled to 0-10 ℃ and contains 10-dodecyl-10H-phenothiazine and DCM, stirring the obtained suspension at 0-10 ℃ overnight, then slowly adding deionized water and stirring for 20-40 minutes, then adding saturated saline and extracting to obtain an organic phase; then dried over magnesium sulfate, filtered, the solvent removed, and then purified by column chromatography using a solvent in a volume ratio of 40: 1 petroleum ether: ethyl acetate is used as eluent to obtain 3, 7-dibromo-10-dodecyl-phenothiazine; is light yellow oil;

or the process of the step one is as follows: slowly adding NaH stored in mineral oil into a DMF flask containing 3, 6-dibromo-9H-carbazole and cooled to 0-5 ℃, slowly adding 1-bromododecane after 10-30 minutes, stirring the obtained suspension at 0-10 ℃ overnight, slowly adding deionized water, filtering, and washing with petroleum ether to obtain the 3, 6-dibromo-9-dodecyl-carbazole which is gray solid.

4. The method for preparing a two-photon polymerization initiator with an A-pi-D-pi-A structure according to claim 3, wherein in the first step, the mass fraction of NaH stored in mineral oil is 60%; the molar ratio of NaH to phenothiazine is 1.2-2: 1; the molar ratio of the phenothiazine to the 1-bromododecane is 1: 1-1.5; the mass-volume ratio of the phenothiazine to the DMF is 1g: 6-10 mL; the molar ratio of the 10-dodecyl-10H-phenothiazine to the NBS is 1: 2-3; the molar volume ratio of the 10-dodecyl-10H-phenothiazine to DCM is 1mmol:4 mL;

the molar ratio of NaH to 3, 6-dibromo-9H-carbazole is 1.2-2: 1; the molar ratio of the 3, 6-dibromo-9H-carbazole to the 1-bromododecane is 1: 1-1.5; the mass-volume ratio of the 3, 6-dibromo-9H-carbazole to the DMF is 1g: 4-8 mL.

5. The method for preparing the a-pi-D-pi-a structure two-photon polymerization initiator according to claim 2, wherein the process of the second step is: adding 3, 7-dibromo-10-dodecyl-phenothiazine, CuI and PdCl into a reactor₂(PPh₃)₂、PPh₃1, 1-dimethyl-2-butyn-1-ol and triethylamine, refluxing the mixture at 85-90 deg.C for 8-9 hr under Ar protection, cooling, removing solvent, pouring the residue into saturated brine and extracting with ethyl acetate for 3 times100mL each time, combine the organic layers and use MgSO₄Dried, concentrated, and applied at a volume ratio of 6: 1 petroleum ether and ethyl acetate as eluent, and purifying by column chromatography to obtain 4- [ 10-dodecyl-7- (3-hydroxy-3-) (methyl-butyl-1-alkynyl) -phenothiazin-3-yl]-2-methyl-but-3-yn-2-ol as a pale yellow oil;

or the process of the step two is as follows: adding 3, 6-dibromo-9-dodecyl-carbazole, CuI and PdCl into a reactor₂(PPh₃)₂、PPh₃Refluxing the mixture at 85-90 deg.C for 8-9 hr under Ar protection, cooling, removing solvent, pouring the residue into saturated saline and extracting with ethyl acetate for 3 times (100mL each time), combining the organic layers, and adding MgSO 5₄Dried, concentrated, and applied at a volume ratio of 6: 1 petroleum ether and ethyl acetate as eluent, purifying by column chromatography to obtain 4- [ 9-dodecyl-6- (3-hydroxy-3-methyl-but-1-ynyl) -carbazol-3-yl]-2-methyl-but-3-yn-2-ol as a pale yellow oil.

6. The method for preparing a two-photon polymerization initiator with an A-pi-D-pi-A structure according to claim 5, wherein in the second step, the molar ratio of the 3, 7-dibromo-10-dodecyl-phenothiazine to the CuI is 8-12: 1; the 3, 7-dibromo-10-dodecyl-phenothiazine and PdCl₂(PPh₃)₂The molar ratio of (A) to (B) is 18-22: 1; the 3, 7-dibromo-10-dodecyl-phenothiazine and PPh₃The molar ratio of (A) to (B) is 1: 80-120; the molar ratio of the 3, 7-dibromo-10-dodecyl-phenothiazine to the 1, 1-dimethyl-2-butyne-1-ol is 1: 2.5-4; the mass-volume ratio of the 3, 7-dibromo-10-dodecyl-phenothiazine to triethylamine is 1g: 13-17 mL;

in the second step, the molar ratio of the 3, 6-dibromo-9-dodecyl-carbazole to the CuI is 8-12: 1; the 3, 6-dibromo-9-dodecyl-carbazole and PdCl₂(PPh₃)₂The molar ratio of (A) to (B) is 18-22: 1; the 3, 6-dibromo-9-dodecyl-carbazole and PPh₃The molar ratio of (A) to (B) is 1: 80-120; the 3, 6-dibromo-9-dodecyl-carbazole and the 1, 1-dimethyl-2-butaneThe molar ratio of the alkyne-1-alcohol is 1: 2.5-4; the mass-volume ratio of the 3, 6-dibromo-9-dodecyl-carbazole to the triethylamine is 1g: 13-17 mL.

7. The method for preparing the A-pi-D-pi-A structure two-photon polymerization initiator according to claim 2, wherein the process in the third step is as follows: adding potassium hydroxide to an isopropanol solution containing 4- [ 10-dodecyl-7- (3-hydroxy-3-) (methyl-but-1-ynyl) -phenothiazin-3-yl ] -2-methyl-but-3-yn-2-ol, refluxing the resulting mixture at 85 to 90 ℃ for 2.5 to 4 hours under Ar protection, cooling while keeping argon gas under reflux after completion of the reaction, concentrating, dissolving in ethyl acetate, extracting 3 times with saturated saline solution, 50mL each time, drying over anhydrous magnesium sulfate and concentrating, purifying a dark brown residue by column chromatography using a volume ratio of 20: 1, and taking petroleum ether and ethyl acetate as eluent to obtain 10-dodecyl-3, 7-diacetylene-phenothiazine as light yellow oily matter;

or the process in the third step is as follows: adding potassium hydroxide into an isopropanol solution containing 4- [ 9-dodecyl-6- (3-hydroxy-3-methyl-but-1-alkynyl) -carbazol-3-yl ] -2-methyl-but-3-yn-2-ol, refluxing the obtained mixture at 85-90 ℃ for 2.5-4 hours under the protection of Ar, cooling while keeping introducing argon after the reaction is completed, concentrating, dissolving in ethyl acetate, extracting for 3 times with saturated saline solution, 50mL each time, drying with anhydrous magnesium sulfate and concentrating, purifying a dark brown residue by column chromatography, and purifying with a solvent with a volume ratio of 20: 1 with petroleum ether and ethyl acetate as eluent, to give 9-dodecyl-3, 6-diacetylene-carbazole as a pale yellow oil.

8. The method for preparing the A-pi-D-pi-A structure two-photon polymerization initiator according to claim 7, wherein the molar ratio of the 4- [ 10-dodecyl-7- (3-hydroxy-3-) (methyl-but-1-ynyl) -phenothiazin-3-yl ] -2-methyl-but-3-yn-2-ol to the potassium hydroxide is 1:5 to 7; the molar volume ratio of the 4- [ 10-dodecyl-7- (3-hydroxy-3-) (methyl-butyl-1-alkynyl) -phenothiazin-3-yl ] -2-methyl-butyl-3-alkyne-2-alcohol to isopropanol is 5mmol: 40-60 mL;

the molar ratio of the 4- [ 9-dodecyl-6- (3-hydroxy-3-methyl-butyl-1-alkynyl) -carbazole-3-yl ] -2-methyl-butyl-3-alkyne-2-alcohol to potassium hydroxide is 1: 5-7; the molar volume ratio of the 4- [ 10-dodecyl-7- (3-hydroxy-3-) (methyl-butyl-1-alkynyl) -phenothiazin-3-yl ] -2-methyl-butyl-3-alkyne-2-alcohol to isopropanol is 5mmol: 40-60 mL.

9. The method for preparing the a-pi-D-pi-a structure two-photon polymerization initiator according to claim 2, wherein the process of the fourth step is: adding 10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole into a reactor, and then adding PdCl₂(PPh₃)₂、PPh₃(4-bromo-phenyl) -phenyl-methanone, triethylamine and DMF and degassed with Ar for 10-15 min, refluxing the resulting mixture for 8 h, cooling, removing the solvent, pouring the residue into saturated brine and extracting with ethyl acetate 3 times 30mL each, combining the organic layers, MgSO 2₄Drying, concentrating and purifying by column chromatography to obtain products of molecular structural formula (I) and molecular structural formula (III);

or the process of the fourth step is as follows: adding 10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole into a reactor, and then adding PdCl₂(PPh₃)₂、PPh₃2-bromo-9-fluorenone, triethylamine and DMF, and degassing with Ar for 10-15 min, refluxing the resulting mixture for 8 hours, cooling, removing the solvent, pouring the residue into saturated brine and extracting with ethyl acetate for 3 times 30mL each, combining the organic layers, MgSO 2₄Drying, concentrating and purifying by column chromatography to obtain the products of molecular structural formula (II) and molecular structural formula (IV).

10. The method for preparing a two-photon polymerization initiator with an A-pi-D-pi-A structure according to claim 9, wherein in the fourth step: the molar ratio of the 10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole to the CuI is 8-12: 1; the above-mentioned10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole with PdCl₂(PPh₃)₂The molar ratio of (A) to (B) is 18-22: 1; the 10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole and PPh₃The molar ratio of (A) to (B) is 1: 80-120; the molar ratio of the 10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole to the (4-bromo-phenyl) -phenyl-methanone is 1: 2-4; the molar volume ratio of the 10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole to triethylamine is 1mmol:200 mL; the molar volume ratio of the 10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole to DMF is 1mmol:100 mL;

the molar ratio of the 10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole to the 2-bromo-9-fluorenone is 1: 2-4.

Technical Field

The invention belongs to the technical field of micro-nano manufacturing and chemical engineering, and particularly relates to a two-photon polymerization initiator with an A-pi-D-pi-A structure and a preparation method thereof.

Background

The two-photon effect is a third-order nonlinear effect. In 1931, Goppert-Mayer theorized that the molecule would undergo two-photon absorption (TPA) under intense light excitation. However, until the appearance of high-energy lasers, the TPA phenomenon was not observed by researchers. The two-photon absorption of the substance may occur when the intensity of the light irradiation reaches the megawatt level. Due to the special property of two-photon absorption to absorb two photons at a time, a large number of applications based on this effect are derived. Two-photon photopolymerization (TPP) three-dimensional (3D) additive manufacturing is one of the most important applications of two-photon absorption. Since the intensity of TPA is proportional to the square of the intensity of incident light and if the laser intensity is adjusted so that only the intensity at the focal point reaches the photon density required for the generation of TPA, TPA is confined to a small fraction of the cube of the wavelength of the incident light and thus the induced chemical reaction occurs only in this region, TPA has a high degree of spatial selectivity and resolution. In addition, the wavelength of the TPA light source is near infrared light, so that Rayleigh scattering loss and dielectric absorption of laser can be effectively reduced, and biological materials are not damaged. This broadens the application of two-photon polymerization additive manufacturing.

However, the numerous applications of two-photon polymeric additive manufacturing also face some problems. In this process, after a photoinitiator is mixed with a monomer resin, polymerization of the monomer is initiated by the laser. The efficiency of the photoinitiator directly affects the polymerization effect as well as the production rate and resolution. However, current two-photon photoinitiators are still relatively inefficient and inadequate for a number of applications. Therefore, the research of high-efficiency two-photon initiators is very important.

Disclosure of Invention

An object of the present invention is to solve at least the above problems and/or disadvantages and to provide at least the advantages described hereinafter.

To achieve these objects and other advantages in accordance with the present invention, there is provided an a-pi-D-pi-a structure two-photon polymerization initiator, which is formed of a phenothiazine or carbazole molecule connected to a benzophenone or fluorenone group through a carbon-carbon triple bond as a conjugate bridge, and has a molecular structural formula:

the invention also provides a preparation method of the A-pi-D-pi-A structure two-photon polymerization initiator, which comprises the following steps:

firstly, adding alkyl into phenothiazine and 3, 6-dibromo-9H-carbazole serving as raw materials through a substitution reaction for protection; carrying out bromination reaction on phenothiazine, and introducing para-bromine;

step two, carrying out Sonogashira coupling reaction on the product obtained in the step one, and introducing acetylene hydroxyl groups;

step three, performing deprotection on the product obtained in the step two to remove hydroxyl;

and step four, performing Sonogashira coupling reaction on the product obtained in the step three, and introducing a functional electron-withdrawing group.

Preferably, the process of the first step is as follows: slowly adding NaH stored in mineral oil into a phenothiazine-containing DMF solution which is cooled to 0-5 ℃, and slowly adding 1-bromododecane after 10-30 minutes; stirring the obtained solution at 0-5 ℃ overnight, and slowly adding deionized water; after stirring for half an hour, extraction with ethyl acetate and then purification by column chromatography using a 40: 1, petroleum ether and ethyl acetate are used as eluent to obtain 10-dodecyl-10H-phenothiazine which is light yellow oily matter;

slowly adding NBS into a solution which is cooled to 0-10 ℃ and contains 10-dodecyl-10H-phenothiazine and DCM, stirring the obtained suspension at 0-10 ℃ overnight, then slowly adding deionized water and stirring for 20-40 minutes, then adding saturated saline and extracting to obtain an organic phase; then dried over magnesium sulfate, filtered, the solvent removed, and then purified by column chromatography using a solvent in a volume ratio of 40: 1 petroleum ether: ethyl acetate is used as eluent to obtain 3, 7-dibromo-10-dodecyl-phenothiazine; is light yellow oil;

or the process of the step one is as follows: slowly adding NaH stored in mineral oil into a DMF flask containing 3, 6-dibromo-9H-carbazole, which is cooled to 0-5 ℃, after 10-20 minutes, slowly adding 1-bromododecane, stirring the obtained suspension at 0-5 ℃ overnight, slowly adding deionized water, filtering, and washing with petroleum ether to obtain 3, 6-dibromo-9-dodecyl-carbazole which is gray solid;

preferably, in the first step, the mass fraction of the NaH stored in the mineral oil is 60%; the molar ratio of NaH to phenothiazine is 1.2-2: 1; the molar ratio of the phenothiazine to the 1-bromododecane is 1: 1-1.5; the mass-volume ratio of the phenothiazine to the DMF is 1g: 6-10 mL; the molar ratio of the 10-dodecyl-10H-phenothiazine to the NBS is 1: 2-3; the molar volume ratio of the 10-dodecyl-10H-phenothiazine to DCM is 1mmol:4 mL;

the molar ratio of NaH to 3, 6-dibromo-9H-carbazole is 1.2-2: 1; the molar ratio of the 3, 6-dibromo-9H-carbazole to the 1-bromododecane is 1: 1-1.5; the mass-volume ratio of the 3, 6-dibromo-9H-carbazole to the DMF is 1g: 4-8 mL;

preferably, the process of step two is as follows: adding 3, 7-dibromo-10-dodecyl-phenothiazine, CuI and PdCl into a reactor₂(PPh₃)₂、PPh₃Refluxing the mixture at 85-90 deg.C for 8-9 hr under Ar protection, cooling, removing solvent, pouring the residue into saturated saline and extracting with ethyl acetate for 3 times (100mL each time), combining the organic layers, and adding MgSO 5₄Dried, concentrated, and applied at a volume ratio of 6: 1 petroleum ether and ethyl acetate as eluent, and purifying by column chromatographyReacting to obtain 4- [ 10-dodecyl-7- (3-hydroxy-3-) (methyl-butyl-1-alkynyl) -phenothiazin-3-yl]-2-methyl-but-3-yn-2-ol as a pale yellow oil;

or the process of the step two is as follows: adding 3, 6-dibromo-9-dodecyl-carbazole, CuI and PdCl into a reactor₂(PPh₃)₂、PPh₃Refluxing the mixture at 85-90 deg.C for 8-9 hr under Ar protection, cooling, removing solvent, pouring the residue into saturated saline and extracting with ethyl acetate for 3 times (100mL each time), combining the organic layers, and adding MgSO 5₄Dried, concentrated, and applied at a volume ratio of 6: 1 petroleum ether and ethyl acetate as eluent, purifying by column chromatography to obtain 4- [ 9-dodecyl-6- (3-hydroxy-3-methyl-but-1-ynyl) -carbazol-3-yl]-2-methyl-but-3-yn-2-ol as a pale yellow oil.

Preferably, in the second step, the molar ratio of the 3, 7-dibromo-10-dodecyl-phenothiazine to the CuI is 8-12: 1; the 3, 7-dibromo-10-dodecyl-phenothiazine and PdCl₂(PPh₃)₂The molar ratio of (A) to (B) is 18-22: 1; the 3, 7-dibromo-10-dodecyl-phenothiazine and PPh₃The molar ratio of (A) to (B) is 1: 80-120; the molar ratio of the 3, 7-dibromo-10-dodecyl-phenothiazine to the 1, 1-dimethyl-2-butyne-1-ol is 1: 2.5-4; the mass-volume ratio of the 3, 7-dibromo-10-dodecyl-phenothiazine to triethylamine is 1g: 13-17 mL;

in the second step, the molar ratio of the 3, 6-dibromo-9-dodecyl-carbazole to the CuI is 8-12: 1; the 3, 6-dibromo-9-dodecyl-carbazole and PdCl₂(PPh₃)₂The molar ratio of (A) to (B) is 18-22: 1; the 3, 6-dibromo-9-dodecyl-carbazole and PPh₃The molar ratio of (A) to (B) is 1: 80-120; the molar ratio of the 3, 6-dibromo-9-dodecyl-carbazole to the 1, 1-dimethyl-2-butyne-1-ol is 1: 2.5-4; the mass-volume ratio of the 3, 6-dibromo-9-dodecyl-carbazole to the triethylamine is 1g: 13-17 mL;

preferably, the process in step three is as follows: adding potassium hydroxide to an isopropanol solution containing 4- [ 10-dodecyl-7- (3-hydroxy-3-) (methyl-but-1-ynyl) -phenothiazin-3-yl ] -2-methyl-but-3-yn-2-ol, refluxing the resulting mixture at 85 to 90 ℃ for 2.5 to 4 hours under Ar protection, cooling while keeping argon gas under reflux after completion of the reaction, concentrating, dissolving in ethyl acetate, extracting 3 times with saturated saline solution, 50mL each time, drying over anhydrous magnesium sulfate and concentrating, purifying a dark brown residue by column chromatography using a volume ratio of 20: 1, and taking petroleum ether and ethyl acetate as eluent to obtain 10-dodecyl-3, 7-diacetylene-phenothiazine as light yellow oily matter;

or the process in the third step is as follows: adding potassium hydroxide into an isopropanol solution containing 4- [ 9-dodecyl-6- (3-hydroxy-3-methyl-but-1-alkynyl) -carbazol-3-yl ] -2-methyl-but-3-yn-2-ol, refluxing the obtained mixture at 85-90 ℃ for 2.5-4 hours under the protection of Ar, cooling while keeping introducing argon after the reaction is completed, concentrating, dissolving in ethyl acetate, extracting for 3 times with saturated saline solution, 50mL each time, drying with anhydrous magnesium sulfate and concentrating, purifying a dark brown residue by column chromatography, and purifying with a solvent with a volume ratio of 20: 1 with petroleum ether and ethyl acetate as eluent, to give 9-dodecyl-3, 6-diacetylene-carbazole as a pale yellow oil.

Preferably, the molar ratio of the 4- [ 10-dodecyl-7- (3-hydroxy-3-) (methyl-but-1-alkynyl) -phenothiazin-3-yl ] -2-methyl-but-3-alkyne-2-alcohol to the potassium hydroxide is 1: 5-7; the molar volume ratio of the 4- [ 10-dodecyl-7- (3-hydroxy-3-) (methyl-butyl-1-alkynyl) -phenothiazin-3-yl ] -2-methyl-butyl-3-alkyne-2-alcohol to isopropanol is 5mmol: 40-60 mL;

the molar ratio of the 4- [ 9-dodecyl-6- (3-hydroxy-3-methyl-butyl-1-alkynyl) -carbazole-3-yl ] -2-methyl-butyl-3-alkyne-2-alcohol to potassium hydroxide is 1: 5-7; the molar volume ratio of the 4- [ 10-dodecyl-7- (3-hydroxy-3-) (methyl-butyl-1-alkynyl) -phenothiazin-3-yl ] -2-methyl-butyl-3-alkyne-2-alcohol to isopropanol is 5mmol: 40-60 mL.

Preferably, the process of step four is as follows: adding 10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole into a reactor, and then adding PdCl₂(PPh₃)₂、PPh₃(4-bromo-phenyl) -phenyl-methanone, triethylamine and DMF and degassed with Ar for 10-15 min, refluxing the resulting mixture for 8 h, cooling, removing the solvent, pouring the residue into saturated brine and extracting with ethyl acetate 3 times 30mL each, combining the organic layers, MgSO 2₄Drying, concentrating and purifying by column chromatography to obtain products of molecular structural formula (I) and molecular structural formula (III);

or the process of the fourth step is as follows: adding 10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole into a reactor, and then adding PdCl₂(PPh₃)₂、PPh₃2-bromo-9-fluorenone, triethylamine and DMF, and degassing with Ar for 10-15 min, refluxing the resulting mixture for 8 hours, cooling, removing the solvent, pouring the residue into saturated brine and extracting with ethyl acetate for 3 times 30mL each, combining the organic layers, MgSO 2₄Drying, concentrating and purifying by column chromatography to obtain the products of molecular structural formula (II) and molecular structural formula (IV).

Preferably, in the fourth step: the molar ratio of the 10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole to the CuI is 8-12: 1; the 10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole and PdCl₂(PPh₃)₂The molar ratio of (A) to (B) is 18-22: 1; the 10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole and PPh₃The molar ratio of (A) to (B) is 1: 80-120; the molar ratio of the 10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole to the (4-bromo-phenyl) -phenyl-methanone is 1: 2-4; the molar volume ratio of the 10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole to triethylamine is 1mmol:200 mL; the molar volume ratio of the 10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole to DMF is 1mmol:100 mL;

the molar ratio of the 10-dodecyl-3, 7-diacetylene-phenothiazine or 9-dodecyl-3, 6-diacetylene-carbazole to the 2-bromo-9-fluorenone is 1: 2-4.

The invention at least comprises the following beneficial effects:

(1) the A-pi-D-pi-A structure two-photon polymerization initiators prepared by the invention have good stability and two-photon polymerization activity, and the scanning rate of the two-photon polymerization reaction processing by using the A-pi-D-pi-A structure two-photon polymerization initiators is high, and the microstructure precision is good.

(2) The preparation method of the phenothiazine and carbazolyl two-photon initiator with the A-pi-D-pi-A structure is simple and convenient, simple in purification, short in required time, and high in purity of the obtained product.

(3) The optical property and the two-photon polymerization performance of the initiator are researched, and the result shows that the initiator with the best performance can reach 2000 mu m/s at the laser power of 50mw in the polymerization process.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.

Description of the drawings:

FIG. 1 is a chemical reaction formula of step one to step four in examples 1, 2, 5 and 6 of the present invention;

FIG. 2 is a chemical reaction formula of step five in examples 1 and 5 of the present invention;

FIG. 3 is a chemical reaction formula of step five in examples 2 and 6 of the present invention;

FIG. 4 is a chemical reaction formula of step one to step four in examples 3, 4, 7 and 8 of the present invention;

FIG. 5 is a chemical reaction formula of step five in examples 3 and 7 of the present invention;

FIG. 6 is a chemical reaction formula of step five in examples 4 and 8 of the present invention;

FIG. 7 is a nuclear magnetic hydrogen spectrum of the product of examples 1 and 5 of the present invention;

FIG. 8 is a nuclear magnetic hydrogen spectrum of the products of examples 2 and 6 of the present invention;

FIG. 9 is a nuclear magnetic hydrogen spectrum of the products of examples 3 and 7 of the present invention;

FIG. 10 is a nuclear magnetic hydrogen spectrum of the products of examples 4 and 8 of the present invention;

FIG. 11 is an overall SEM image of a structure formed by polymerization initiated by the products of examples 1 and 5.

FIG. 12 is a scanning electron microscope image of a portion of the detail of the structure formed by the polymerization initiated by the product of examples 1 and 5.

The specific implementation mode is as follows:

the present invention is further described in detail below with reference to the attached drawings so that those skilled in the art can implement the invention by referring to the description text.

It will be understood that terms such as "having," "including," and "comprising," as used herein, do not preclude the presence or addition of one or more other elements or groups thereof.