WO2017166914A1

WO2017166914A1 - Three-arm atrp initiator with planar-conjugated structure and preparation method thereof

Info

Publication number: WO2017166914A1
Application number: PCT/CN2017/072222
Authority: WO
Inventors: 戴李宗; 吴俣哲; 袁丛辉; 毛杰; 李云同; 许一婷; 曾碧榕; 罗伟昂
Original assignee: 厦门大学
Priority date: 2016-04-01
Filing date: 2017-01-23
Publication date: 2017-10-05
Also published as: CN105622788B; CN105622788A

Abstract

The present invention relates to a preparation method of a three-arm atom transfer radical polymerization (ATRP) initiator with a planar-conjugated structure. First, 1,3,5-tris(4-aminophenyl)benzene is reacted in a nucleophilic substitution reaction with bromoisobutyryl bromide under triethylamine catalysis to prepare a high-efficiency three-arm ATRP initiator with extensive planar conjugation and electron-rich characteristics. Second, an optimal reaction system and after-treatment method suitable for the initiator is selected. A self-assembly study corresponding to a three-arm amphiphilic macromolecular polymer prepared via ATRP polymerization using the initiator is conducted. The three-arm ATRP initiator of the present invention not only meets the need for a planar-conjugated, electron-rich aromatic ATRP initiator, but is also suitable for polymerization of various types of monomer, thereby having good application potential.

Description

Three-arm ATRP initiator with planar conjugate structure and preparation method thereof

Technical field

The invention relates to a kind of polymerization reaction in polymer polymerization chemistry, in particular to a preparation method of a three-arm ATRP initiator having a planar conjugate structure.

Background technique

Atom transfer radical polymerization (ATRP) is one of the most widely used methods for polymer synthesis. The polymerization method has the dual characteristics of free radical polymerization and living polymerization, and has good universality, strong controllability and low cost. The polymer synthesized by the method can not only achieve the expected polymerization molecular weight, but also achieve a narrow distribution range and high yield of the polymer, and thus is an effective tool for designing a novel macromolecular structure. In recent years, it has become common to synthesize multi-arm and star-shaped polymers by ATRP polymerization, and has gradually become a research hotspot in the field of polymer chemistry. At present, by synthesizing the reaction conditions of ATRP, the synthesis of random copolymers, regular block copolymers, three-armed polymers, multi-arm polymers and star polymers and inorganic hybrid materials can be smoothly realized.

Common ATRP initiators mainly include halogenated alkane RX (X=Br, Cl), α-bromo esters, α-bromo ketones, etc. [Chemical Reviews, 2009, 109, 5595-5619]. The ATRP initiator can also be classified into a small molecule ATRP initiator and a macromolecular ATRP initiator depending on the molecular weight. Among the small molecule initiators, the three-arm small molecule ATRP initiator is characterized by a rich chemical structure and a complex spatial structure but also regular [Biomacromolecules-2015, 16, 723-732]. More importantly, small molecule initiators with highly planar conjugate properties and rich electrical properties are more conducive to the spatial arrangement and orientation of polymer chains, and are important tools for polymer structure design in polymer science.

At present, three-arm small molecule ATRP initiators with highly planar conjugation and high electrical properties have rarely been reported. The reason is that the chemical structure design of the initiator is complicated, the synthesis process is difficult, the raw materials are difficult to obtain, the cost is expensive, the applicable polymerization reaction system is also extremely complicated, and the post-treatment is difficult. Therefore, the main purpose of the patent is to overcome the defects of the prior art. A novel three-arm small molecule ATRP initiator having a highly planar conjugated nature and an electrically enhanced property is provided. Firstly, a novel three-arm small molecule ATRP initiator was synthesized by nucleophilic substitution reaction of 1,3,5-tris(4-aminophenyl)benzene and bromoisobutyryl bromide under the catalysis of triethylamine. The initiator has the characteristics of highly planar conjugate properties and rich electrical properties as well as efficient chain transfer. Its Learning structure:

Secondly, the optimal reaction system and post-treatment method suitable for the initiator were screened out. The three-arm amphiphilic polymer was synthesized by ATRP polymerization using the initiator to carry out corresponding self-assembly research.

Summary of the invention

The invention aims to provide a preparation method of a three-arm ATRP initiator having a planar conjugate structure and application thereof

The synthesis method and application of the three-arm ATRP initiator are carried out as follows:

Synthesis of a three-arm ATRP initiator:

(1) Dissolving 0.5 to 1 part of 1,3,5-tris(4-aminophenyl)benzene and 1 to 3 parts by volume of bromoisobutyryl bromide in 10 parts by volume of dichloromethane solution, and placing in ice The bath conditions were stirred for 10 minutes. 2 to 5 parts by volume of a triethylamine solution was slowly added, and stirred at room temperature overnight. After completion of the reaction, purification was carried out by column chromatography, and the eluent was petroleum ether and ethyl acetate. The solid obtained was recrystallized from absolute ethanol to give a three-armed ATRP initiator.

Second, three-arm ATRP initiator application:

(1) 0.5 to 1 part of initiator, 0.3 to 1 part by volume of tris(2-dimethylaminoethyl)amine, 0.1 to 0.3 part of cuprous bromide, and 1 to 3 parts by volume of t-butyl acrylate in DMF solution among. The mixture was degassed by continuous freeze-thaw three times, and after argon gas protection, it was placed in an oil bath at 90 ° C for 24 hours. After the reaction was completed, the copper salt was removed through a neutral alumina column. A white solid polymer was obtained by precipitation from a mixed solution of methanol and water. The white solid polymer and 3 to 5 parts by volume of trifluoroacetic acid were dissolved in dichloromethane. The reaction was stirred at room temperature for 24 hours. After completion of the reaction, precipitation was carried out by using a mixed solution of methanol and water to obtain an amphiphilic three-arm white solid polymer.

(2) 0.5 to 1 part of an initiator, 0.3 to 1 part by volume of tris(2-dimethylaminoethyl)amine, 0.1 to 0.3 part of cuprous bromide, and 1 to 3 parts by volume of styrene are dissolved in a toluene solution. After degassing by continuous freeze-thaw three times, it was argon-protected and placed in an oil bath at 90 ° C for 24 hours. After the reaction is over, pass through The alumina column removes the copper salt. The macromolecular chain transfer agent white solid obtained after precipitation by a mixed solution of methanol and water. The macromolecular chain transfer agent, 0.3 to 1 part by volume of tris(2-dimethylaminoethyl)amine, 0.1 to 1 part of cuprous bromide, and 1 to 3 parts by volume of t-butyl acrylate are dissolved in the DMF solution. After degassing by continuous freeze-thaw three times, it was argon-protected and placed in an oil bath at 90 ° C for 24 hours. After the reaction was completed, the copper salt was removed through a neutral alumina column. Further, precipitation was carried out by using a mixed solution of methanol and water to obtain a block polymer white solid. The block polymer white solid and 3 to 5 parts by volume of trifluoroacetic acid were dissolved in dichloromethane. The reaction was stirred at room temperature for 24 hours. After completion of the reaction, the mixture was precipitated with a mixed solution of methanol and water to a three-armed amphiphilic block polymer in the form of a white solid.

(3) 0.1 to 0.3 parts of a three-armed amphiphilic polymer solid is dissolved in 1 to 3 parts by volume of a tetrahydrofuran solution, added dropwise to 10 parts by volume of distilled water, and stirred overnight at room temperature in the dark. The resulting liquid is the self-assembled solution of the three-armed amphiphilic polymer. Further morphology studies and applications are carried out by the self-assembly solution.

The three-arm ATRP initiator synthesized by the invention has the following characteristics:

(1) The structure of the three-arm initiator in the present invention is ingeniously designed, the synthesis step is simple, and the yield is high. The initiator has a high degree of planar conjugation and power enrichment as well as efficient initiation activity and chain transfer.

(2) The optimum reaction system and post-treatment method of the three-arm ATRP initiator are screened in the present invention. The reaction system has good universality, strong operability, simple post-treatment process and little environmental pollution, and can be applied to ATRP controlled polymerization of various monomers.

(3) The polymer synthesized by the initiator in the present invention can be self-assembled in a solvent, and the self-assembly behavior of the polymer can be artificially controlled and further researched and applied by controlling the degree of polymerization.

(4) At present, there is no high-plane conjugated and electrically-rich three-arm ATRP initiator which can be directly purchased and used on the market. The present invention can make up for this blank well and has a good market prospect.

DRAWINGS

Figure 1 is a nuclear magnetic resonance spectrum of a three-arm ATRP initiator with a nuclear magnetic spectroscopy: 9.90 (3H, s), 7.90 to 7.81 (15H, m), 2.04 (18H, s);

Figure 2 is a GPC spectrum of a three-armed amphiphilic ATRP polymer;

detailed description

The present invention will be further described in detail below with reference to the embodiments.

Example 1

(1) 0.5 g of 1,3,5-tris(4-aminophenyl)benzene and 1 ml of bromoisobutyryl bromide were dissolved in 10 ml of a dichloromethane solution, and the mixture was stirred for 10 minutes under ice bath. 2 ml of triethylamine solution was slowly added and stirred at room temperature overnight. After completion of the reaction, purification was carried out by column chromatography, and the eluent was petroleum ether and ethyl acetate. The solid obtained was recrystallized from 10 ml of absolute ethanol to give a white solid of a three-armed ATRP initiator.

(2) 0.5 g of an initiator, 0.3 ml of tris(2-dimethylaminoethyl)amine, 0.1 g of cuprous bromide, and 1 ml of t-butyl acrylate were dissolved in a DMF solution. The mixture was degassed by continuous freeze-thaw three times, and after argon gas protection, it was placed in an oil bath at 90 ° C for 24 hours. After the reaction was completed, the copper salt was removed through a neutral alumina column. Precipitation by a mixed solution of methanol and water gave a white solid polymer. The white solid polymer and 3 ml of trifluoroacetic acid were dissolved in dichloromethane. The reaction was stirred at room temperature for 24 hours. After completion of the reaction, precipitation was carried out by using a mixed solution of methanol and water to obtain a white solid of the amphiphilic three-armed polymer.

(3) 0.5 g of an initiator, 0.3 ml of tris(2-dimethylaminoethyl)amine, 0.1 g of cuprous bromide, and 1 ml of styrene were dissolved in a toluene solution. After degassing by continuous freeze-thaw three times, it was argon-protected and placed in an oil bath at 90 ° C for 24 hours. After the reaction was completed, the copper salt was removed through a neutral alumina column. The macromolecular chain transfer agent white solid obtained after precipitation by a mixed solution of methanol and water. A macromolecular chain transfer agent, 0.3 ml of tris(2-dimethylaminoethyl)amine, 0.1 cuprous bromide, and 1 t-butyl acrylate were dissolved in a DMF solution. After degassing by continuous freeze-thaw three times, it was argon-protected and placed in an oil bath at 90 ° C for 24 hours. After the reaction was completed, the copper salt was removed through a neutral alumina column. Further, precipitation was carried out by using a mixed solution of methanol and water to obtain a block polymer white solid. The block polymer white solid and 3 ml of trifluoroacetic acid were dissolved in dichloromethane. The reaction was stirred at room temperature for 24 hours. After completion of the reaction, precipitation was carried out by using a mixed solution of methanol and water to obtain a three-armed amphiphilic block polymer as a white solid.

(4) 0.1 g of a three-arm amphiphilic polymer solid was dissolved in 3 ml of tetrahydrofuran solution, added dropwise to 10 ml of distilled water, and stirred overnight at room temperature in the dark. The resulting liquid is the self-assembled solution of the three-armed amphiphilic polymer. Further morphological studies and application.

Example 2

(1) 1 g of 1,3,5-tris(4-aminophenyl)benzene and 2 ml of bromoisobutyryl bromide were dissolved in 10 ml of a dichloromethane solution, and the mixture was stirred for 10 minutes in an ice bath. 3 ml of triethylamine solution was slowly added, and stirred at room temperature overnight. After completion of the reaction, purification was carried out by column chromatography, and the eluent was petroleum ether and ethyl acetate. The solid obtained was recrystallized from 15 ml of absolute ethanol to give a white solid of a three-armed ATRP initiator.

(2) 1 g of an initiator, 0.5 ml of tris(2-dimethylaminoethyl)amine, 0.2 g of cuprous bromide, and 2 ml of t-butyl acrylate were dissolved in a DMF solution. The mixture was degassed by continuous freeze-thaw three times, and after argon gas protection, it was placed in an oil bath at 90 ° C for 24 hours. After the reaction was completed, the copper salt was removed through a neutral alumina column. Precipitation by a mixed solution of methanol and water gave a white solid polymer. The white solid polymer and 3 ml of trifluoroacetic acid were dissolved in dichloromethane. The reaction was stirred at room temperature for 24 hours. After completion of the reaction, precipitation was carried out by using a mixed solution of methanol and water to obtain a white solid of the amphiphilic three-armed polymer.

(3) 1 g of an initiator, 0.5 ml of tris(2-dimethylaminoethyl)amine, 0.2 g of cuprous bromide, and 2 ml of styrene were dissolved in a toluene solution. After degassing by continuous freeze-thaw three times, it was argon-protected and placed in an oil bath at 90 ° C for 24 hours. After the reaction was completed, the copper salt was removed through a neutral alumina column. The macromolecular chain transfer agent white solid obtained after precipitation by a mixed solution of methanol and water. A macromolecular chain transfer agent, 0.5 ml of tris(2-dimethylaminoethyl)amine, 0.2 cuprous bromide, and t-butyl 2 acrylate were dissolved in a DMF solution. After degassing by continuous freeze-thaw three times, it was argon-protected and placed in an oil bath at 90 ° C for 24 hours. After the reaction was completed, the copper salt was removed through a neutral alumina column. Further, precipitation was carried out by using a mixed solution of methanol and water to obtain a block polymer white solid. The block polymer white solid and 5 ml of trifluoroacetic acid were dissolved in dichloromethane. The reaction was stirred at room temperature for 24 hours. After completion of the reaction, precipitation was carried out by using a mixed solution of methanol and water to obtain a three-armed amphiphilic block polymer as a white solid.

(4) 0.15 g of a three-arm amphiphilic polymer solid was dissolved in 5 ml of tetrahydrofuran solution, added dropwise to 10 ml of distilled water, and stirred overnight at room temperature in the dark. The resulting liquid is the self-assembled solution of the three-armed amphiphilic polymer. Further morphology studies and applications are carried out by the self-assembly solution.

Example 3

(1) 1.5 g of 1,3,5-tris(4-aminophenyl)benzene and 4 ml of bromoisobutyryl bromide were dissolved in 10 ml of a dichloromethane solution, and the mixture was stirred for 10 minutes in an ice bath. 5 ml of triethylamine solution was slowly added, and stirred at room temperature overnight. After completion of the reaction, purification was carried out by column chromatography, and the eluent was petroleum ether and ethyl acetate. The solid obtained was recrystallized from 20 ml of absolute ethanol to give a white solid of a three-armed ATRP initiator.

(2) 1.5 g of an initiator, 1 ml of tris(2-dimethylaminoethyl)amine, 0.5 g of cuprous bromide, and 4 ml of t-butyl acrylate were dissolved in a DMF solution. The mixture was degassed by continuous freeze-thaw three times, and after argon gas protection, it was placed in an oil bath at 90 ° C for 24 hours. After the reaction was completed, the copper salt was removed through a neutral alumina column. Precipitation by a mixed solution of methanol and water gave a white solid polymer. The white solid polymer and 3 ml of trifluoroacetic acid were dissolved in dichloromethane. The reaction was stirred at room temperature for 24 hours. After completion of the reaction, precipitation was carried out by using a mixed solution of methanol and water to obtain a white solid of the amphiphilic three-armed polymer.

(3) 1.5 g of an initiator, 0.6 ml of tris(2-dimethylaminoethyl)amine, 0.3 g of cuprous bromide, and 3 ml of styrene were dissolved in a toluene solution. After degassing by continuous freeze-thaw three times, it was argon-protected and placed in an oil bath at 90 ° C for 24 hours. After the reaction was completed, the copper salt was removed through a neutral alumina column. The macromolecular chain transfer agent white solid obtained after precipitation by a mixed solution of methanol and water. The macromolecular chain transfer agent, 0.5 ml of tris(2-dimethylaminoethyl)amine, 0.6 cuprous bromide, and tert-butyl triacrylate were dissolved in the DMF solution. After degassing by continuous freeze-thaw three times, it was argon-protected and placed in an oil bath at 90 ° C for 24 hours. After the reaction was completed, the copper salt was removed through a neutral alumina column. Further, precipitation was carried out by using a mixed solution of methanol and water to obtain a block polymer white solid. The block polymer white solid and 5 ml of trifluoroacetic acid were dissolved in dichloromethane. The reaction was stirred at room temperature for 24 hours. After completion of the reaction, precipitation was carried out by using a mixed solution of methanol and water to obtain a three-armed amphiphilic block polymer as a white solid.

(4) 0.2 g of the three-arm amphiphilic polymer solid was dissolved in 5 ml of tetrahydrofuran solution, added dropwise to 10 ml of distilled water, and stirred overnight at room temperature in the dark. The resulting liquid is the self-assembled solution of the three-armed amphiphilic polymer. Further morphology studies and applications are carried out by the self-assembly solution.

Claims

A three-arm ATRP initiator having a planar conjugate structure characterized by a chemical structural formula:
The method for preparing a three-arm ATRP initiator having a planar conjugate structure according to claim 1, wherein the specific steps are as follows:

Dissolve 1,3,5-tris(4-aminophenyl)benzene and bromoisobutyryl bromide in dichloromethane solution, stir under ice bath, add triethylamine solution, and then pass column chromatography. Purification was carried out, and the obtained solid was recrystallized from absolute ethanol to obtain a three-armed ATRP initiator having a planar conjugated structure.
A method for preparing a three-arm ATRP initiator having a planar conjugate structure according to claim 2, wherein said 1,3,5-tris(4-aminophenyl)benzene, bromoisobutyryl bromide, and The ratio of the methyl chloride solution to the triethylamine solution is (0.5 to 1) g: (1 to 3) ml: 10 ml: (2 to 5) ml, wherein 1,3,5-tris(4-aminophenyl) Benzene is calculated by mass, brominated isobutyryl bromide, dichloromethane solution, triethylamine solution by volume.
A method of preparing a three-arm ATRP initiator having a planar conjugate structure according to claim 2, wherein the stirring time in the ice bath condition is 10 minutes.
A method of producing a three-armed ATRP initiator having a planar conjugate structure according to claim 2, wherein the eluent used for purification by column chromatography is petroleum ether and ethyl acetate.
A three-armed ATRP initiator having a planar conjugated structure as claimed in claim 1 for use in the preparation of a self-assembling solution of an amphiphilic three-armed solid polymer, a three-armed amphiphilic block polymer, and a three-armed amphiphilic polymer.
The use according to claim 6, characterized in that the specific method of preparing the amphiphilic three-arm white solid polymer with a planar conjugated three-arm ATRP initiator is as follows:

0.5 to 1 part of a three-arm ATRP initiator having a planar conjugated structure, 0.3 to 1 part by volume of tris(2-dimethylaminoethyl)amine, 0.1 to 0.3 part of cuprous bromide, and 1 to 3 parts by volume of acrylic acid unbranched Butyl ester was dissolved in DMF solution, degassed by continuous freeze-thaw three times. After argon gas protection, it was placed in an oil bath at 90 °C for 24 h. After the reaction was completed, the copper salt was removed through a neutral alumina column and then passed through methanol. After precipitation with a mixed solution of water, a white solid polymer is obtained; the white solid polymer and 3 to 5 parts of trifluoroacetic acid are dissolved in dichloromethane, and the reaction is stirred at room temperature for 24 hours. After the reaction is completed, methanol and water are used again. The mixed solution was precipitated to obtain an amphiphilic three-arm white solid polymer.
The use according to claim 6, wherein the specific method of preparing the three-armed amphiphilic block polymer having the planar conjugated structure is as follows:

0.5 to 1 part of a three-arm ATRP initiator having a planar conjugate structure, 0.3 to 1 part by volume of tris(2-dimethylaminoethyl)amine, 0.1 to 0.3 part of cuprous bromide, and 1 to 3 parts by volume of styrene Dissolved in toluene solution, degassed by continuous freeze-thaw three times, argon-protected and placed in an oil bath at 90 °C for 24 h. After the reaction is completed, the copper salt is removed through a neutral alumina column, through methanol and water. The mixed solution is precipitated to obtain a macromolecular chain transfer agent white solid; a macromolecular chain transfer agent, 0.3 to 1 part by volume of tris(2-dimethylaminoethyl)amine, 0.1 to 1 part of cuprous bromide and 1 ~3 parts by volume of tert-butyl acrylate dissolved in DMF solution, degassed by continuous freeze-thaw three times, argon-protected and placed in an oil bath at 90 ° C for 24 h, after the reaction, through a neutral alumina column The copper salt was removed and precipitated with a mixed solution of methanol and water to obtain a block polymer white solid. The block polymer white solid and 3 to 5 parts by volume of trifluoroacetic acid were dissolved in dichloromethane, and the reaction was stirred for 24 hours. And using a mixed solution of methanol and water to precipitate, that is, a three-armed amphiphilic white solid Block polymer.
The use according to claim 6, wherein the application method of the three-arm ATRP initiator having a planar conjugate structure in preparing a self-assembly solution of a three-arm amphiphilic polymer is as follows:

1) 0.5 to 1 part of a three-arm ATRP initiator having a planar conjugate structure, 0.3 to 1 part by volume of tris(2-dimethylaminoethyl)amine, 0.1 to 0.3 part of cuprous bromide, and 1 to 3 parts by volume Styrene was dissolved in toluene solution, degassed by continuous freeze-thaw three times, argon-protected and placed in an oil bath at 90 ° C for 24 h. After the reaction was completed, the copper salt was removed through a neutral alumina column and passed through methanol. a macromolecular chain transfer agent white solid obtained by precipitation with a mixed solution of water; a macromolecular chain transfer agent, 0.3 to 1 part by volume of tris(2-dimethylaminoethyl)amine, 0.1 to 1 part of cuprous bromide And 1-3 parts by volume of tert-butyl acrylate dissolved in DMF solution, degassed by continuous freeze-thaw three times, argon-protected and placed in an oil bath at 90 ° C After 24 h, after the reaction is completed, the copper salt is removed through a neutral alumina column, and then precipitated by a mixed solution of methanol and water to obtain a block polymer white solid, which is a block polymer white solid and 3 to 5 parts by volume The fluoroacetic acid is dissolved in dichloromethane, and the reaction is stirred for 24 hours, and then precipitated by using a mixed solution of methanol and water to obtain a three-armed amphiphilic block polymer in the form of a white solid;

2) 0.1 to 0.3 parts of the three-armed amphiphilic block polymer solid obtained in the step 1) is dissolved in 1 to 3 parts by volume of a tetrahydrofuran solution, and then added to 10 parts by volume of distilled water, and stirred overnight in the dark, the resulting liquid is a three-arm. Self-assembly solution of amphiphilic polymer.