阅读说明：本技术 丙烯酰-n-异丙基甘氨酰胺单体及其制备方法 (acryloyl-N-isopropyl glycinamide monomer and preparation method thereof ) 是由 刘文广 张卓丹 杨建海 于 2019-09-26 设计创作，主要内容包括：本发明公开了一种丙烯酰-N-异丙基甘氨酰胺单体及其制备方法。具体地说,是以N-(叔丁氧基羰基)甘氨酸甲酯和异丙胺、丙烯酰氯为原料,在一定的条件下反应生成丙烯酰-N-异丙基甘氨酰胺。丙烯酰-N-异丙基甘氨酰胺带有双键,可进行自由基聚合。同时,丙烯酰-N-异丙基甘氨酰胺带有疏水性的异丙基和两个亲水性的酰胺基团,后者可以提供双氢键结构。异丙基可赋予聚合物分子类似于聚(N-异丙基丙烯酰胺)的温度特性,双氢键结构使得聚合物分子间和分子内具有多重氢键作用。因此,该单体可以聚合形成聚合物,从而获得具有特殊温敏性的聚合物材料,在生物工程领域有着潜在的应用价值。(The invention discloses an acryloyl-N-isopropyl glycinamide monomer and a preparation method thereof. Specifically, N- (tert-butoxycarbonyl) glycine methyl ester, isopropylamine and acryloyl chloride are used as raw materials and react under certain conditions to generate acryloyl-N-isopropyl glycinamide. The acryloyl-N-isopropyl glycinamide has double bonds and can be subjected to free radical polymerization. At the same time, acryloyl-N-isopropyl glycinamide carries a hydrophobic isopropyl group and two hydrophilic amide groups, the latter of which can provide a double hydrogen bond structure. The isopropyl group can endow the polymer molecules with temperature characteristics similar to that of poly (N-isopropyl acrylamide), and the double hydrogen bond structure enables multiple hydrogen bonds to act between and in the polymer molecules. Therefore, the monomer can be polymerized to form a polymer, so that a polymer material with special temperature sensitivity is obtained, and the polymer material has potential application value in the field of bioengineering.)

1. An acryloyl-N-isopropyl glycinamide monomer, which is characterized in that: having a molecular structure shown below

2. A preparation method of an acryloyl-N-isopropyl glycinamide monomer is characterized by comprising the following steps: the method comprises the following steps:

(1) mixing N- (tert-butoxycarbonyl) glycine methyl ester, isopropylamine and triethylamine, and stirring at room temperature to react the N- (tert-butoxycarbonyl) glycine methyl ester with the isopropylamine, wherein the molar ratio of the N- (tert-butoxycarbonyl) glycine methyl ester, the isopropylamine and the triethylamine is 1:3.8: 1;

(2) adding the reaction product obtained in the step (1) into dichloromethane, adding trifluoroacetic acid (TFA), and stirring under ice bath conditions to react the reaction product obtained in the step (1) with the trifluoroacetic acid (TFA), wherein the mass ratio of the reaction product obtained in the step (1) to the trifluoroacetic acid is 1: (15-16), wherein the volume ratio of the dichloromethane to the trifluoroacetic acid is 1: 1;

(3) adding the reaction product obtained in the step (2) into water, adding a potassium carbonate solution and diethyl ether, adding a diethyl ether solution of acryloyl chloride into the mixed solution under an ice bath condition, and continuously stirring in the ice bath to enable the reaction product obtained in the step (2) to react with the acryloyl chloride to generate acryloyl-N-isopropyl glycinamide, wherein the mass ratio of the reaction product obtained in the step (2), solvent water, potassium carbonate and acryloyl chloride is 4:3.6: 6: (3.5-4).

3. The process for preparing an acryloyl-N-isopropyl glycinamide monomer according to claim 2, characterized in that: in the step (1), stirring for 3-5 days at the room temperature of 25-30 ℃ for reaction; after the reaction was completed, the reaction solution was concentrated under vacuum, then precipitated in n-hexane, and the solid was dried after filtration to obtain white crystals.

4. The process for preparing an acryloyl-N-isopropyl glycinamide monomer according to claim 2, characterized in that: in the step (2), stirring for 2-4h at the temperature of 0-5 ℃ under an ice bath condition for reaction; and after the reaction is finished, carrying out rotary evaporation and concentration on the reaction solution, then adding a sodium hydroxide solution to adjust the pH of the solution to 10-12, extracting with ethyl acetate, then adding a drying agent into the extract liquor for drying, carrying out suction filtration, and carrying out rotary evaporation and concentration to obtain a light yellow oily liquid.

5. The process for preparing an acryloyl-N-isopropyl glycinamide monomer according to claim 4, characterized in that: and (2) adding a sodium hydroxide solution to adjust the pH value of the solution to 12, and adding a drying agent into the extract for drying for not less than 30min, wherein the drying agent is anhydrous sodium sulfate or anhydrous magnesium sulfate.

6. The process for preparing an acryloyl-N-isopropyl glycinamide monomer according to claim 2, characterized in that: in the step (3), the volume ratio of the solvent water to the potassium carbonate solution to the diethyl ether in the mixed solution is 3.6:24:22, and the volume ratio of the acryloyl chloride to the diethyl ether in the acryloyl chloride solution is 3.3: 14.

7. The process for preparing an acryloyl-N-isopropyl glycinamide monomer according to claim 2, characterized in that: in the step (3), the reaction system is stirred for 3-5h under the ice bath condition of 0-5 ℃ for reaction; and after the reaction is finished, carrying out suction filtration on the reaction liquid, washing the reaction liquid by using ether, and drying the solid to obtain a white solid product.

Technical Field

The invention relates to an acryloyl-N-isopropyl glycinamide monomer and a preparation method thereof, in particular to acryloyl-N-isopropyl glycinamide generated by the reaction of N- (tert-butoxycarbonyl) glycine methyl ester, isopropylamine and acryloyl chloride under certain conditions.

Background

Poly (N-isopropyl acrylamide) (PNIPAAm) is a novel intelligent high polymer material, and because a hydrophilic amide group and a hydrophobic isopropyl group are simultaneously connected to a molecular chain of the poly (N-isopropyl acrylamide), the poly (N-isopropyl acrylamide) has the temperature sensitivity characteristic of being dissolved (precipitated), swelled (contracted) and the like along with the change of temperature. Poly (N-isopropylacrylamide) hydrogels have a lower critical phase transition temperature (LCST), approximately at about 32 ℃. Poly (N-isopropylacrylamide) hydrogels swell highly when the temperature is above the LCST; when the temperature is lower than LCST, the hydrogel will shrink dramatically. Poly (N-isopropyl acrylamide) also has good biocompatibility and no tissue toxicity, and is commonly used in the biomedical fields of drug release, tissue engineering and the like.

N-acryloyl glycinamide (NAGA) is a monomer containing two amide groups, and a high-strength hydrogel can be prepared through free radical polymerization in an aqueous solution, wherein the crosslinking effect of the hydrogel is derived from multiple hydrogen bonding effects in polymer molecules and among molecules. Studies have shown that poly (N-acryloylglycinamide) hydrogels have a high critical phase transition temperature (UCST), with thermoplasticity.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides an acryloyl-N-isopropyl glycyl amine compound and a preparation method thereof.

The technical purpose of the invention is realized by the following technical scheme.

The invention relates to an acryloyl-N-isopropyl glycinamide monomer and a preparation method thereof, which are carried out according to the following steps:

(1) mixing N- (tert-butoxycarbonyl) glycine methyl ester, isopropylamine and triethylamine, and stirring at room temperature to react the N- (tert-butoxycarbonyl) glycine methyl ester with the isopropylamine, wherein the molar ratio of the N- (tert-butoxycarbonyl) glycine methyl ester, the isopropylamine and the triethylamine is 1:3.8: 1;

(2) adding the reaction product obtained in the step (1) into dichloromethane, adding trifluoroacetic acid (TFA), and stirring under ice bath conditions to react the reaction product obtained in the step (1) with the trifluoroacetic acid (TFA), wherein the mass ratio of the reaction product obtained in the step (1) to the trifluoroacetic acid is 1: (15-16), wherein the volume ratio of the dichloromethane to the trifluoroacetic acid is 1: 1;

(3) adding the reaction product obtained in the step (2) into water, adding a potassium carbonate solution and diethyl ether, adding a diethyl ether solution of acryloyl chloride into the mixed solution under an ice bath condition, and continuously stirring in the ice bath to enable the reaction product obtained in the step (2) to react with the acryloyl chloride to generate acryloyl-N-isopropyl glycinamide, wherein the mass ratio of the reaction product obtained in the step (2), solvent water, potassium carbonate and acryloyl chloride is 4:3.6: 6: (3.5-4).

In the step (1), stirring for 3-5 days at the room temperature of 25-30 ℃ for reaction; after the reaction was completed, the reaction solution was concentrated under vacuum, then precipitated in n-hexane, and the solid was dried after filtration to obtain white crystals.

In the step (2), stirring for 2-4h at the temperature of 0-5 ℃ under an ice bath condition for reaction; and after the reaction is finished, carrying out rotary evaporation and concentration on the reaction solution, then adding a sodium hydroxide solution to adjust the pH of the solution to 10-12, extracting with ethyl acetate, then adding a drying agent into the extract liquor for drying, carrying out suction filtration, and carrying out rotary evaporation and concentration to obtain a light yellow oily liquid.

And (2) adding a sodium hydroxide solution to adjust the pH value of the solution to 12, and adding a drying agent into the extract for drying for not less than 30min, wherein the drying agent is anhydrous sodium sulfate or anhydrous magnesium sulfate.

In the step (3), the volume ratio of the solvent water to the potassium carbonate solution to the diethyl ether in the mixed solution is 3.6:24:22, and the volume ratio of the acryloyl chloride to the diethyl ether in the acryloyl chloride solution is 3.3: 14.

In the step (3), the reaction system is stirred for 3-5h under the ice bath condition of 0-5 ℃ for reaction; and after the reaction is finished, carrying out suction filtration on the reaction liquid, washing the reaction liquid by using ether, and drying the solid to obtain a white solid product.

The chemical reactions involved in the present invention are carried out according to the following chemical reaction formulae.

Step 1

Step 2

Step 3

The invention has the beneficial effects that: according to the acryloyl-N-isopropyl glycinamide monomer and the preparation method thereof, N- (tert-butoxycarbonyl) glycine methyl ester, isopropylamine and acryloyl chloride are used as raw materials and react under certain conditions to generate acryloyl-N-isopropyl glycinamide, and the newly generated acryloyl-N-isopropyl glycinamide has double bonds so as to be subjected to free radical polymerization; meanwhile, the newly generated acryloyl-N-isopropyl glycinamide has hydrophobic isopropyl and two hydrophilic amide groups, the latter can provide a double hydrogen bond structure, the isopropyl can endow the polymer molecules with temperature characteristics similar to that of poly (N-isopropyl acrylamide), and the double hydrogen bond structure enables multiple hydrogen bonds among and in the polymer molecules. The acryloyl-N-isopropyl glycinamide prepared by the invention is equivalent to isopropyl substitution on a nitrogen atom at the tail end of N-acryloyl glycinamide (NAGA), so that the polymer of the acryloyl-N-isopropyl glycinamide has high critical phase transition temperature (UCST), low critical phase transition temperature (LCST) and special temperature sensitivity; multiple hydrogen bonding can also be formed within and between molecules, thereby improving the strength of the gel.

Drawings

FIG. 1 is a diagram of acryloyl-N-isopropyl glycinamide of the invention¹H-NMR spectrum.

Detailed Description

The following is a further description of the invention and is not intended to limit the scope of the invention.

Example 1

Step 1, preparing the instruments needed by the experiment, cleaning a round-bottom flask, a beaker and magnetons used for reaction, and drying in an oven. A100 ml measuring cylinder and a glass vial were washed and dried in the same manner. 9ml of N- (tert-butoxycarbonyl) glycine methyl ester, 16ml of isopropylamine and 7ml of triethylamine were pipetted into a round-bottomed flask, followed by addition of a magneton and stirring at room temperature for 3 to 5 days.

And 2, after the reaction is finished, concentrating the reaction solution, pouring the concentrated reaction solution into 500ml of n-hexane for precipitation, filtering to obtain a white solid, washing with n-hexane, and drying in vacuum.

Step 3, 4.3g of the resulting white solid was weighed using a tray balance and added to a dry round bottom flask. 40ml of methylene chloride was added to the flask and stirred until the solid was completely dissolved. Preparing broken ice blocks in advance, putting the broken ice blocks into an aluminum basin, adding a proper amount of water, and carrying out an ice-water bath reaction. 40ml of TFA was measured in a cylinder, added to the above system and stirred at 0 ℃ for 2.5 h.

And 4, after the reaction is finished, pouring the reaction liquid into a rotary evaporation bottle, and concentrating the reaction liquid under a vacuum condition to obtain liquid with high viscosity. The liquid was poured into a beaker, and a 2M NaOH solution was added dropwise to adjust the pH of the reaction solution to 12. Extracted three times with ethyl acetate and the appropriate amount of anhydrous Na2SO4 solid was added to remove water from the extract. The sodium sulfate solid was removed by suction filtration and the solvent removed by rotary evaporation to give a small amount of a pale yellow oily liquid.

Step 5, a round-bottom flask was charged with 4.0g of the above pale yellow oily liquid and 3.6ml of water. 6g K2CO3 solid and 24ml water were added to the beaker and stirred well to make a K2CO3 solution which was added to the round bottom flask described above. Preparing broken ice blocks in advance, putting the broken ice blocks into an aluminum basin, adding a proper amount of water, and carrying out an ice-water bath reaction. 22ml of diethyl ether was added to the above system, and the mixture was subjected to ice-bath. A dry, constant pressure funnel was charged with 14ml of diethyl ether, 3.3ml of acryloyl chloride and added dropwise to the round bottom flask. After all the dropwise addition, the mixture was stirred in ice bath and reacted for 4 hours.

And 6, after the reaction is finished, carrying out suction filtration on the reaction solution to obtain a small amount of white solid, washing with diethyl ether, and carrying out vacuum drying to obtain a final product.

Example 2

Step 1, preparing the instruments needed by the experiment, cleaning a round-bottom flask, a beaker and magnetons used for reaction, and drying in an oven. A100 ml measuring cylinder and a glass vial were washed and dried in the same manner. 9ml of N- (tert-butoxycarbonyl) glycine methyl ester, 16ml of isopropylamine and 7ml of triethylamine were pipetted into a round-bottomed flask, followed by addition of a magneton and stirring at room temperature for 3 to 5 days.

And 2, after the reaction is finished, concentrating the reaction solution, pouring the concentrated reaction solution into 500ml of n-hexane for precipitation, filtering to obtain a white solid, washing with n-hexane, and drying in vacuum.

Step 3, 8.6g of the resulting white solid was weighed using a tray balance and added to a dry round bottom flask. 80ml of methylene chloride was added to the flask and stirred until the solid was completely dissolved. Preparing broken ice blocks in advance, putting the broken ice blocks into an aluminum basin, adding a proper amount of water, and carrying out an ice-water bath reaction. 80ml of TFA was measured out in a cylinder, added to the above system and stirred at 0 ℃ for 2.5 h.

And 4, after the reaction is finished, pouring the reaction liquid into a rotary evaporation bottle, and concentrating the reaction liquid under a vacuum condition to obtain liquid with high viscosity. The liquid was poured into a beaker, and a 2M NaOH solution was added dropwise to adjust the pH of the reaction solution to 12. Extracted three times with ethyl acetate and the appropriate amount of anhydrous Na2SO4 solid was added to remove water from the extract. The sodium sulfate solid was removed by suction filtration and the solvent removed by rotary evaporation to give a small amount of a pale yellow oily liquid.

Step 5, 8.0g of the above pale yellow oily liquid and 7.2ml of water were added to a round-bottomed flask. 12g K2CO3 solid and 48ml of water were added to the beaker and stirred well to produce a K2CO3 solution which was added to the round bottom flask described above. Preparing broken ice blocks in advance, putting the broken ice blocks into an aluminum basin, adding a proper amount of water, and carrying out an ice-water bath reaction. 44ml of diethyl ether was added to the above system, and the mixture was subjected to ice-bath. A dry, constant pressure funnel was charged with 28ml of diethyl ether, 6.6ml of acryloyl chloride and added dropwise to the round bottom flask. After all the dropwise addition, the mixture was stirred in ice bath and reacted for 4 hours.

And 6, after the reaction is finished, carrying out suction filtration on the reaction solution to obtain a small amount of white solid, washing with diethyl ether, and carrying out vacuum drying to obtain a final product.

Example 3

Step 1, preparing the instruments needed by the experiment, cleaning a round-bottom flask, a beaker and magnetons used for reaction, and drying in an oven. A100 ml measuring cylinder and a glass vial were washed and dried in the same manner. 18ml of N- (tert-butoxycarbonyl) glycine methyl ester, 32ml of isopropylamine and 14ml of triethylamine were pipetted into a round-bottomed flask, followed by addition of a magneton and stirring at room temperature for 3 to 5 days.

And 2, after the reaction is finished, concentrating the reaction solution, pouring the concentrated reaction solution into 1000ml of n-hexane for precipitation, filtering to obtain a white solid, washing with n-hexane, and drying in vacuum.

Step 3, weigh 13.2g of the resulting white solid using a tray balance and add to a dry round bottom flask. 120ml of methylene chloride was added to the flask and stirred until the solid was completely dissolved. Preparing broken ice blocks in advance, putting the broken ice blocks into an aluminum basin, adding a proper amount of water, and carrying out an ice-water bath reaction. 120ml of TFA was measured out using a measuring cylinder, added to the above system, and stirred at 0 ℃ for 2.5 hours.

And 4, after the reaction is finished, pouring the reaction liquid into a rotary evaporation bottle, and concentrating the reaction liquid under a vacuum condition to obtain liquid with high viscosity. The liquid was poured into a beaker, and a 2M NaOH solution was added dropwise to adjust the pH of the reaction solution to 12. Extracted three times with ethyl acetate and the appropriate amount of anhydrous Na2SO4 solid was added to remove water from the extract. The sodium sulfate solid was removed by suction filtration and the solvent removed by rotary evaporation to give a small amount of a pale yellow oily liquid.

Step 5, a round-bottom flask was charged with 12.0g of the above pale yellow oily liquid and 10.8ml of water. The beaker was charged with 18g K2CO3 solid and 72ml of water and stirred well to make a K2CO3 solution which was added to the round bottom flask described above. Preparing broken ice blocks in advance, putting the broken ice blocks into an aluminum basin, adding a proper amount of water, and carrying out an ice-water bath reaction. 66ml of diethyl ether was added to the above system, and the mixture was subjected to ice-bath. A dry, constant pressure funnel was charged with 42ml of diethyl ether, 10ml of acryloyl chloride and added dropwise to the round bottom flask. After all the dropwise addition, the mixture was stirred in ice bath and reacted for 4 hours.

And 6, after the reaction is finished, carrying out suction filtration on the reaction solution to obtain a small amount of white solid, washing with diethyl ether, and carrying out vacuum drying to obtain a final product.

By using¹Chemical Structure of acryloyl-N-isopropyl glycinamide prepared in example of the invention by H NMRAs a result of the structural characterization, it is apparent from FIG. 1 that absorption peaks at 6.31ppm, 6.22ppm and 5.68ppm of hydrogen atoms on the double bond of acryloyl-N-isopropyl glycinamide, absorption peaks at 4.07 to 3.90ppm of hydrogen atoms on the alkyl group and absorption peaks at 1.13ppm of hydrogen atoms on the isopropyl group are observed, thus proving that the isopropyl group and the double bond are indeed present, well characterizing the structure of acryloyl-N-isopropyl glycinamide and thus proving that acryloyl-N-isopropyl glycinamide is successfully synthesized.

The preparation of the acryloyl-N-isopropyl glycinamide monomer can be realized by adjusting the process parameters according to the content of the invention, and the performance basically consistent with the embodiment of the invention is shown.

The invention has been described in an illustrative manner, and it is to be understood that any simple variations, modifications or other equivalent changes which can be made by one skilled in the art without departing from the spirit of the invention fall within the scope of the invention.