阅读说明：本技术 适于串联催化的纳米胶束的制备方法 (Preparation method of nano micelle suitable for tandem catalysis ) 是由 陈涛 邱嘉琪 王茂林 于 2021-01-20 设计创作，主要内容包括：本发明公开了一种适于串联催化的纳米胶束的制备方法,该方法的要点是先制备端基含有降冰片烯的RAFT试剂,通过可逆加成-断裂链转移自由基聚合,分别制备带有活化酯功能基团的亲水链段和疏水链段。在疏水段接上催化剂1(有机碱),然后通过开环易位聚合形成刷形聚合物,再在亲水部分接上催化剂2(4-氨基-TEMPO)；最后在水中自组装形成核-壳结构的纳米胶束。催化反应时底物在壳上被催化剂2催化反应后,进入核内,再由催化剂1催化反应,从而实现了高效的串联催化。(The invention discloses a preparation method of a nano micelle suitable for tandem catalysis, which is characterized by firstly preparing an RAFT reagent with norbornene-containing terminal groups, and respectively preparing a hydrophilic chain segment and a hydrophobic chain segment with activated ester functional groups through reversible addition-fragmentation chain transfer free radical polymerization. Grafting a catalyst 1 (organic base) on a hydrophobic section, then forming a brush polymer through ring-opening metathesis polymerization, and then grafting a catalyst 2 (4-amino-TEMPO) on a hydrophilic part; finally self-assembling in water to form nano micelle with a core-shell structure. In the catalytic reaction, the substrate enters the core after being catalyzed and reacted by the catalyst 2 on the shell, and then is catalyzed and reacted by the catalyst 1, so that high-efficiency serial catalysis is realized.)

1. The preparation method of the nano-micelle suitable for tandem catalysis is characterized by comprising the following steps:

1) obtaining a CDP as a chain transfer reagent;

the CDP is 4-cyano (dodecylmercaptothiocarbonylcarbonyl) sulfanylpentanoic acid;

2) and synthesizing a chain transfer reagent CDP-NB with bornylene at the tail end:

dissolving CDP in a solvent I, then adding 5-norbornene-2-methanol, DCC and DMAP, carrying out ice-bath reaction for 25-35 min, and then carrying out room-temperature reaction for 18-22 h;

DCC is dicyclohexylcarbodiimide and DMAP is 4-dimethylaminopyridine;

CDP: 5-norbornene-2-methanol is in a mass ratio of 1: 0.4-1; CDP: DCC is 1: 0.5-2 mass ratio of DCC: DMAP is 1: 0.03-0.12 in mass ratio;

after the reaction is finished, carrying out post-treatment to obtain CDP-NB;

3) and preparing a hydrophobic chain segment:

putting the CDP-NB, MMA, activated ester and AIBN obtained in the step 2) into a container, adding a solvent II, and stirring until the CDP-NB, MMA, activated ester and AIBN are dissolved; after deoxidization, reacting for 9-24 h at 50-70 ℃ under a sealed condition;

MMA: methyl methacrylate; AIBN: azobisisobutyronitrile;

CDP-NB, MMA, activated ester, AIBN ═ 1: 3-6: 3-6: 0.01-0.1 mass ratio;

after the reaction is finished, performing post-treatment to obtain a hydrophobic long chain with a terminal group containing bornylene;

4) and preparing a hydrophobic chain segment with a catalytic function:

dissolving the hydrophobic long chain with the terminal group containing the bornylene obtained in the step 3) and organic base in a solvent III, and reacting at room temperature for 10-24 hours under a sealed condition after deoxygenation;

hydrophobic long chain with a terminal group of bornylene: organic base ═ 1: 0.1-1 mass ratio;

after the reaction is finished, performing post-treatment to obtain a hydrophobic long chain containing amino;

5) and preparing a hydrophilic chain segment:

subjecting the CDP-NB and OEGMA obtained in the step 2) to₃₀₀Adding activated ester and AIBN into a container, adding solvent IV, and stirring until CDP-NB and OEGMA₃₀₀Activated ester and AIBN are dissolved; after deoxidization, reacting for 9-24 h at 50-70 ℃ under a sealed condition;

OEGMA₃₀₀: polyethylene glycol methyl ether methacrylate with molecular weight of 300;

CDP-NB、OEGMA₃₀₀activated ester, AIBN ═ 1: 10-30: 4.5-20: 0.01-0.1 mass ratio;

after the reaction is finished, carrying out post-treatment to obtain a hydrophilic long chain with a terminal group containing bornylene;

6) preparing a molecular brush by ring-opening metathesis polymerization:

under the protection of inert gas, dissolving the hydrophobic long chain containing amino group obtained in the step 4) in a solvent V; adding a catalyst, and reacting for 10-100 min at room temperature in a dark place; the amino-containing hydrophobic long chain obtained in the step 4): catalyst 1: 0.005-0.05 mass ratio;

adding the hydrophilic long chain with the terminal group containing the bornylene obtained in the step 5), and continuously reacting for 5 +/-1 h at the temperature of 30-60 ℃ in a dark place;

the amino-containing hydrophobic long chain obtained in the step 4): the mass ratio of the hydrophilic long chain with the terminal group containing the bornylene obtained in the step 5) is 1: 1-5;

after the reaction is finished, performing post-treatment to obtain a brush polymer;

7) TEMPO loading on Brush polymers:

dissolving the brush polymer obtained in the step 6) and 4-amino-TEMPO in a solvent VI, deoxidizing and uniformly mixing; adding DCC and DMAP under the condition of ice bath; then reacting for 12-40 h at room temperature;

the brush polymer obtained in step 6): 4-amino-TEMPO: DCC, DMAP ═ 1: 0.1-1: 1-2: 0.01-0.2 mass ratio;

after the reaction is finished, carrying out post-treatment to obtain the dual-catalytic-function molecular brush;

8) self-assembly of the molecular brush:

dissolving the dual-catalytic-function molecular brush obtained in the step 7) into a solvent VII, adding ultrapure water, stirring, and drying until the solvent VII is evaporated to obtain a solution containing the nano micelle.

2. The method for preparing nanomicelle suitable for tandem catalysis according to claim 1, wherein: in step 3), MMA: the weight ratio of the activated grease is 20-1: 1.

3. The method for preparing nanomicelle suitable for tandem catalysis according to claim 2, wherein: the activated lipid in the step 3) is any one of the following: n-succinimidyl methacrylate, 1,1,1,3,3, 3-hexafluoroisopropyl acrylate, pentafluorophenol acrylate, and N-succinimidyl acrylate.

4. The method for preparing nanomicelle suitable for tandem catalysis according to any one of claims 1 to 3, wherein:

in the step 4), the organic alkali is DMAP-NH₂，DABCO-NH₂。

5. The method for preparing nanomicelle suitable for tandem catalysis according to claim 4, wherein in the step 5), OEGMA₃₀₀: the weight ratio of the activated ester is 20-1: 1.

6. The method for preparing nanomicelle suitable for tandem catalysis according to any of claims 1 to 3, wherein the catalyst of step 6) is Grubbs I, Grubbs II, Grubbs III.

7. The method for preparing nanomicelle suitable for tandem catalysis according to any one of claims 1 to 3,

the solvent I in the step 2) is dichloromethane;

the solvent II in the step 3) is dioxane, tertiary amyl alcohol and ethanol;

the solvent III in the step 4) is dichloromethane, ethanol and dimethyl sulfoxide;

the solvent IV in the step 5) is dioxane, tertiary amyl alcohol and ethanol;

the solvent V in the step 6) is dioxane, tertiary amyl alcohol and ethanol; dichloromethane;

the solvent VI in the step 7) is DMSO, DMF, ethanol and dichloromethane;

the solvent VII in the step 8) is methanol, tetrahydrofuran or ethanol.

8. The method for preparing nanomicelle suitable for tandem catalysis according to any one of claims 1 to 3,

in the step 8), 0.1g of the dual-catalytic-function molecular brush obtained in the step 7) is matched with 0.2-2 ml of solvent VII and 2-10 ml of ultrapure water.

Technical Field

The invention discloses a preparation method of nano-micelle suitable for tandem catalysis, belongs to the technical field of polymer synthesis and application, and relates to a method for preparing nano-micelle containing bifunctional catalyst based on norbornene ring-opening metathesis polymerization.

Background

Nowadays, environmental protection is an important factor to be considered in every industrial breakthrough or technological progress, and environmentally friendly and sustainable production is a major direction of development in the chemical industry field. To achieve more environmentally friendly organic reactions, scientists have developed various methods to reduce environmental risks while achieving high efficiency of chemical reactions. The organic catalyst is fixed on the polymer to realize the recovery and the reuse of the catalyst, and the method takes an important step in the greening of the catalytic reaction. Furthermore, the amphiphilic block polymer is used as a carrier, and the catalytic nano micelle is prepared in the water phase, so that the water phase catalytic reaction is realized, and the use of an organic solvent can be reduced. In addition, the nano micelle catalysis is similar to homogeneous catalysis, and has the characteristics of high speed and high efficiency.

Two or more catalytic reactions are connected in series and carried out in sequence, so that the separation and purification of reaction intermediates can be avoided, and the reaction process is simplified. Frechet et al, based on star polymers, separately prepared acid and base catalyst-containing nano-micelles, and simultaneously added to a reaction system, achieved a one-pot tandem catalytic reaction. However, incompatible catalysts tend to interact with each other under one-bath conditions, thereby reducing catalytic efficiency. The two catalysts are fixed in the same nano micelle, and are separated by using a physical structure, so that mutual influence is avoided, and the serial catalysis of two or more organic reactions is realized, thereby having important significance.

The ring-opening metathesis polymerization (ROMP) method can synthesize polymer molecular brushes with controllable molecular weight and narrow molecular weight distribution, and brush type block copolymers can be synthesized by sequentially adding monomers. Herein, a hydrophilic macromonomer and a hydrophobic macromonomer having a norbornene group (NB) at the terminal and having a reactive functional group are prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization; preparing an amphiphilic block brush copolymer by utilizing sequential ROMP of hydrophilic macromonomer and hydrophobic macromonomer; respectively loading different catalysts such as 2,2,6, 6-tetramethylpiperidine oxide (TEMPO), 4-Dimethylaminopyridine (DMAP) and the like on a hydrophilic part and a hydrophobic part of the brush copolymer by a high-efficiency chemical reaction method; the nano reactor with a core-shell structure and containing the bifunctional catalyst is constructed through water phase self-assembly. Compared with the core-shell type nano reactor prepared by self-assembling of the linear amphiphilic block copolymer, the nano reactor assembled by the brush type block structure has stable structure and better separation effect between core shells, and can obviously reduce the mutual influence of incompatible structures in the nano reactor. In addition, TEMPO is loaded on the shell layer of the nano-reactor according to the diffusion path of the reactant, and basic catalysts such as DMAP are loaded in the core of the nano-reactor, so that the serial reaction is facilitated to be carried out in sequence, and the reaction efficiency is improved.

Disclosure of Invention

The invention aims to provide a preparation method of nano-micelle suitable for tandem catalysis.

In order to solve the technical problems, the invention provides a preparation method of a nano micelle suitable for tandem catalysis, which has the following main reaction formula:

the preparation method comprises the following steps:

1) obtaining a CDP as a chain transfer reagent;

the CDP is 4-cyano (dodecylmercaptothiocarbonylcarbonyl) sulfanylpentanoic acid;

2) and synthesizing a chain transfer reagent CDP-NB with bornylene at the tail end:

dissolving CDP in a solvent I, then adding 5-norbornene-2-methanol, DCC and DMAP, carrying out ice-bath reaction for 25-35 min, and then carrying out room-temperature reaction for 18-22 h;

DCC is dicyclohexylcarbodiimide and DMAP is 4-dimethylaminopyridine;

CDP: 5-norbornene-2-methanol at a mass ratio of 1:0.4 to 1 (preferably 1:0.4 to 0.6); CDP: DCC is 1: 0.5 to 2 (preferably 1:1 to 1.5), DCC: DMAP is 1: 0.03-0.12 (preferably 1: 0.06-0.1);

after the reaction is finished, carrying out post-treatment (filtration, washing, drying and purification of filtrate) to obtain CDP-NB;

description of the drawings: the DCC and DMAP were added as follows: firstly dissolving the mixture in a solvent I, and then adding the mixture in a solution dropwise manner;

3) and preparing a hydrophobic chain segment:

putting the CDP-NB, MMA, activated ester (such as NHSMA) and AIBN obtained in the step 2) into a container, adding a solvent II, and stirring until the CDP-NB, MMA, activated ester and AIBN are dissolved; after deoxygenation (freeze-thaw cycle for deoxygenation), reacting for 9-24 h at 50-70 ℃ under a sealed condition (preferably reacting for 6-12 h at 60-65 ℃);

MMA: methyl methacrylate; AIBN: azobisisobutyronitrile;

CDP-NB, MMA, activated ester, AIBN ═ 1: 3-6: 3-6: 0.01 to 0.1 (preferably 1: 4 to 5: 0.01 to 0.05) by mass;

after the reaction is finished, performing post-treatment (sealing is cancelled, the obtained reaction solution is dripped into cooling ether at 0-5 ℃, and insoluble solids are collected) to obtain a hydrophobic long chain with a terminal group containing bornylene;

when the activated ester is NHSMA, the obtained hydrophobic long chain with the terminal group carrying the bornene is NB-CDP-P (MMA)_x1-co-NHSMA_y1)；

4) Preparation of hydrophobic segments with catalytic function (organic bases attached to the polymer by activated ester strategy):

mixing the hydrophobic long chain with terminal bornylene obtained in step 3) with organic base (such as DMAP-NH)₂) Dissolving the mixture in a solvent III, and reacting at room temperature for 10-24 h under a sealed condition after deoxygenation (introducing nitrogen to remove oxygen for 15-60 min, preferably for 15-30 min);

hydrophobic long chain with a terminal group of bornylene: organic base ═ 1: 0.1 to 1 (preferably 1:0.2) by weight;

after the reaction is finished, performing post-treatment (sealing is cancelled, the reaction solution is dripped into cooling ether at 0-5 ℃, and insoluble solids are collected) to obtain a hydrophobic long chain containing amino;

the reaction formula is that R is DMAP-NH₂When the organic base is DMAP-NH₂When the hydrophobic long chain containing amino is NB-CDP-P (MMA)_x1-co-DMAP_y1)；

The method comprises the following steps: the organic base is attached to the polymer by an activated ester strategy;

5) and preparing a hydrophilic chain segment:

subjecting the CDP-NB and OEGMA obtained in the step 2) to₃₀₀Activated ester (such as NHSMA), AIBN in a vessel, adding solvent IV, and stirring until CDP-NB and OEGMA₃₀₀Activated ester and AIBN are dissolved; after deoxygenation (freeze-thaw cycle for deoxygenation), reacting for 9-24 h (preferably 6-12 h at 60-65 ℃) at 50-70 ℃ under a sealed condition;

OEGMA₃₀₀: polyethylene glycol methyl ether methacrylate with molecular weight of 300;

CDP-NB、OEGMA₃₀₀activated ester, AIBN ═ 1: 10-30: 4.5-20: 0.01 to 0.1 (preferably 1:20 to 25: 4.5 to 10: 0.01 to 0.04);

after the reaction is finished, performing post-treatment (sealing is cancelled, the obtained reaction solution is dripped into cooling ether at 0-5 ℃, and insoluble solids are collected) to obtain a hydrophilic long chain with a terminal group containing bornylene;

when the activated ester is NHSMA, the obtained hydrophilic long chain with the end group carrying the bornene is NB-CDP-P (OEGMA)_x2-co-NHSMA_y2)；

6) Preparing a molecular brush by ring-opening metathesis polymerization:

under the protection of inert gas, dissolving the hydrophobic long chain containing amino group obtained in the step 4) in a solvent V; adding a catalyst (such as Grubbs 3), and reacting for 10-100 min (preferably 20-30 min) at room temperature in the absence of light; the amino-containing hydrophobic long chain obtained in the step 4): catalyst 1: 0.005 to 0.05 (preferably 1:0.03 to 0.05);

adding the hydrophilic long chain with the terminal group containing the bornylene obtained in the step 5), and continuously reacting for 5 +/-1 h at the temperature of 30-60 ℃ in a dark place;

the amino-containing hydrophobic long chain obtained in the step 4): the mass ratio of the hydrophilic long chain with the terminal bornylene obtained in the step 5) to 1: 1-5 (preferably 1: 2-4);

after the reaction is finished (adding ethyl vinyl ether to quench the reaction); performing post-treatment (dripping the reaction solution into cooling ether at 0-5 ℃, collecting insoluble solids) to obtain a brush-shaped polymer (molecular brush);

description of the drawings: the adding mode of the hydrophilic long chain with the terminal group containing the bornylene obtained in the step 5) is as follows: firstly dissolving in a solvent V, and then adding in a solution dropwise manner;

z₁and z₂The ratio of (A) to (B) is 1: 1-5;

7) TEMPO loading on Brush polymers:

dissolving the brush polymer obtained in the step 6) and 4-amino-TEMPO in a solvent VI, deoxidizing and uniformly mixing; adding DCC and DMAP under the condition of ice bath; then reacting for 12-40 h (preferably 36 +/-2 h) at room temperature;

the brush polymer obtained in step 6): 4-amino-TEMPO: DCC, DMAP ═ 1: 0.1-1: 1-2: 0.01 to 0.2 (preferably, brush polymer: 4-amino-TEMPO ═ 1: 0.1 to 0.4: 1 to 2: 0.1 to 0.2);

after the reaction is finished, performing post-treatment (dropwise adding the reaction solution into a mixed solution of diethyl ether and petroleum ether in a volume ratio of 1:1, and collecting insoluble solids) to obtain the dual-catalytic-function molecular brush;

the reaction formula is that R is DMAP-NH₂When the current is over;

8) self-assembly of molecular brush (preparation of nano-micelle of the macromolecular brush by solvent exchange method):

dissolving the dual-catalytic-function molecular brush obtained in the step 7) into a solvent VII, adding ultrapure water, stirring, and drying until the solvent VII is evaporated to obtain a solution containing the nano micelle.

As an improvement of the preparation method of the nano-micelle suitable for tandem catalysis of the present invention: in step 3), MMA: the weight ratio of the activated grease is 20-1: 1.

I.e. x₁:y₁＝20～1:1。

As a further improvement of the preparation method of the nano-micelle suitable for tandem catalysis of the present invention: the activated lipid in the step 3) is any one of the following: n-succinimidyl methacrylate (NHSMA), 1,1,1,3,3, 3-hexafluoroisopropyl acrylate (HFIPA), pentafluorophenol acrylate (PFPF), N-succinimidyl acrylate (NHSA).

That is, Z may be selected from the following structures:

as a further improvement of the preparation method of the nano-micelle suitable for tandem catalysis of the present invention: in the step 4), the organic alkali is DMAP-NH₂，DABCO-NH₂。

That is, R may be selected to be DMAP-NH₂，DABCO-NH₂。

As a further improvement of the preparation method of the nano-micelle suitable for tandem catalysis of the present invention: in step 5), OEGMA₃₀₀: the weight ratio of the activated ester is 20-1: 1.

I.e. x₂:y₂＝20～1:1。

As a further improvement of the preparation method of the nano-micelle suitable for tandem catalysis of the present invention: the catalyst of step 6) may be Grubbs I, Grubbs II, Grubbs III.

As a further improvement of the preparation method of the nano-micelle suitable for tandem catalysis of the present invention:

the solvent I in the step 2) is Dichloromethane (DCM);

the solvent II in the step 3) is dioxane, tertiary amyl alcohol and ethanol;

the solvent III in the step 4) is dichloromethane, ethanol and dimethyl sulfoxide (DMSO);

the solvent IV (polymerization solvent) in the step 5) is dioxane, tertiary amyl alcohol and ethanol;

the solvent V in the step 6) is dioxane, tertiary amyl alcohol and ethanol; dichloromethane;

the solvent VI in the step 7) is DMSO, DMF, ethanol and dichloromethane.

The solvent VII in the step 8) is methanol, tetrahydrofuran or ethanol.

As a further improvement of the preparation method of the nano-micelle suitable for tandem catalysis of the present invention: in the step 8), 0.1g of the dual-catalytic-function molecular brush obtained in the step 7) is matched with 0.2-2 ml of solvent VII and 2-10 ml of ultrapure water.

The invention is based on ring-opening metathesis polymerization method to prepare macromolecular brush polymer containing double catalysts and prepare nano micelle. The double catalyst refers to the organic base of step 4) and the 4-amino-TEMPO of step 7). The system does not contain noble metal, and can realize the direct synthesis from alcohol compounds to unsaturated compounds without separating and purifying intermediate products in the preparation process.

Step 1) of the invention, Synthesis of chain transfer reagent CDP

The addition of NaH in a mass ratio of 0.5-3: 7 (preferably 1-2: 7) to n-dodecanethiol can promote the normal reaction. And (3) continuing to react for 1-5 h after adding the solid iodine, and preferably for 1-2 h. And carrying out reflux reaction at 75 ℃ for 5-24 h, preferably 20-24 h.

The invention relates to a method for preparing nano-micelle containing a bifunctional catalyst based on ring-opening metathesis polymerization of norbornene; the method is characterized in that firstly, a RAFT reagent with norbornene at the end group is prepared, and a hydrophilic chain segment and a hydrophobic chain segment with activated ester functional groups are respectively prepared through reversible addition-fragmentation chain transfer free radical polymerization (RAFT polymerization). The hydrophobic segment is grafted with catalyst 1 (organic base) and then by ring opening metathesis polymerization (ROMP ring opening) to form a brush polymer, and the hydrophilic portion is grafted with catalyst 2 (4-amino-TEMPO). Finally self-assembling in water to form nano micelle with a core-shell structure. In the catalytic reaction, the substrate enters the core after being catalyzed and reacted by the catalyst 2 on the shell, and then is catalyzed and reacted by the catalyst 1, so that high-efficiency serial catalysis is realized.

The invention has the following technical advantages:

the invention combines two important unit reactions (alcohol oxidation and Knoevenagel condensation reaction) into a one-step reaction at the same time, and obtains higher catalytic efficiency. Can be recycled after the catalytic reaction is finished, avoids the problem of secondary environmental pollution and has important environmental and economic benefits.

Drawings

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of the catalytic process of example 1;

FIG. 2 is Dynamic Light Scattering (DLS) of example 1;

fig. 3 is a transmission scanning electron microscope (TEM) of the nanomicelle prepared in example 1.

Detailed Description

The invention will be further described with reference to specific examples, but the scope of the invention is not limited thereto:

CDP: 4-cyano (dodecylthiocarbonylthiocarbonyl) sulfanylpentanoic acid

DCM: dichloromethane;

DCC: dicyclohexylcarbodiimide;

DMAP: 4-dimethylaminopyridine;

MMA: methyl methacrylate;

NHSMA: n-succinimidyl methacrylate;

AIBN: azobisisobutyronitrile;

DMAP-NH₂: n '-methyl-N' -pyridylethylenediamine, synthetic reference Hasenknopf, Chemistry-A European Journal 2014,20(49), 16074-16077;

OEGMA₃₀₀: polyethylene glycol methyl ether methacrylate, molecular weight 300;

4-amino-TEMPO: 4-amino-2, 2,6, 6-tetramethylpiperidine-1-oxyl radical

In the present invention, it is not explicitly reported that the temperature is at room temperature (10 to 25 ℃).

The dripping time is 10-15 min.

Example 1:

1) and synthesizing a chain transfer reagent CDP:

add 1.6g NaH to 80ml of anhydrous ether and mix well. Under ice-bath conditions, 7.0g of n-dodecylmercaptan are added dropwise, and 3.0g of carbon disulfide are added further. The reaction was carried out at room temperature for 1 hour, 3.2g of solid iodine was added, and the reaction was continued at room temperature for 2 hours. Filtered and washed three times with 40 x 3ml of saturated sodium thiosulfate solution. The water in the system was removed with anhydrous magnesium sulfate, filtered, and concentrated (40 ℃ C. distillation under reduced pressure until all the organic solvent was evaporated) to obtain 5.8g of bis (dodecylsulfanylthiocarbonyl) disulfide.

5.8g of bis (dodecylsulfanylthiocarbonyl) disulfide was dissolved in 100ml of ethyl acetate, and 5.5g of 4,4' -azobis (4-cyanovaleric acid) was added and reacted at 75 ℃ under reflux for 24 hours. Concentrating (40 deg.C, vacuum distilling until all organic solvent is evaporated), and purifying by column chromatography (ethyl acetate: petroleum ether 1:20, V/V) to obtain 4-cyano (dodecylthio thiocarbonyl) sulfanylpentanoic acid (CDP);

the column chromatography method adopts 200-mesh silica gel column, and adopts ethyl acetate: petroleum ether is 1:20 (V/V) is used as eluent, the eluent is collected and distilled under reduced pressure, and 4-cyano (dodecyl thio carbonyl) sulfanyl pentanoic acid is obtained.

2) And synthesis of chain transfer reagent with bornylene at the end:

adding 1.0g CDP into a round-bottom flask containing 5ml DCM, stirring to dissolve, adding 0.6g 5-norbornene-2-methanol, firstly dropwise adding 3ml DCM solution containing 1.0g DCC, and then dropwise adding 2ml DCM solution containing 0.06g DMAP; after 30min of ice-bath reaction, the ice-bath was removed and the reaction was continued at room temperature for 20 h.

After the reaction was complete, the reaction was filtered and the filtrate was taken up with 30X 3ml of saturated NaHCO₃And 30 × 3ml of saturated brine were successively washed three times, and dried over 1.5g of anhydrous sodium sulfate. Finally, purifying the product by silica gel column chromatography with ethyl acetate and n-hexane (volume ratio is 1:20) to obtain CDP-NB;

the column chromatography method adopts a 200-mesh silica gel column, and the reaction is carried out by mixing ethyl acetate and n-hexane 1:20 (V/V) is used as eluent, the dosage of the eluent is 500ml, 300ml of eluent corresponding to the eluent is collected, and reduced pressure distillation is carried out to obtain CDP-NB;

3) and preparing a hydrophobic chain segment:

0.1g of CDP-NB, 0.49g of MMA, 0.49g of NHSMA, 3.2mg of AIBN were weighed into an appropriate vial, 2ml of dioxane was added, and the above 4 were dissolved by stirring and sonication. Transfer to a polymerization ampoule and freeze-thaw cycle three times to remove oxygen. The reaction is carried out for 12 hours in a water bath kettle at 65 ℃ under sealed conditions.

After the reaction was completed, the bottle was opened to expose the reaction system to air. The reaction solution was added dropwise, drop by drop, to 200ml of cooled (0-5 ℃) constantly stirred petroleum ether: collecting insoluble solid in mixed solution of ethyl ether 1:1 to obtain hydrophobic long-chain NB-CDP-P (MMA) of terminal base bornene₂₅-co-NHSMA₁₂)。

4) And preparing a hydrophobic chain segment with a catalytic function:

0.1g of NB-CDP-P (MMA)₂₅-co-NHSMA₁₂) And 0.02g DMAP-NH₂Dissolved in 3ml of dichloromethane, dissolved and mixed well. The reaction was deoxygenated by nitrogen for 15 minutes and sealed overnight (about 10 hours) at room temperature.

After the reaction was completed, the reaction vessel was opened. Dropping the reaction solution into 200ml of cooled and constantly stirred diethyl ether, and collecting insoluble solids to obtain the hydrophobic long-chain NB-CDP-P (MMA) containing amino₂₅-co-DMAP₁₂)。

5) And preparing a hydrophilic chain segment:

0.1g CDP-NB, 2.25g OEGMA were weighed out₃₀₀0.49g NHSMA, 3.2mg AIBN in a suitable vial, 5ml ethanol added, stirred and sonicated to dissolve. Transfer to a polymerization ampoule and freeze-thaw cycle three times to remove oxygen. The reaction is carried out for 12 hours in a water bath kettle at 65 ℃ under sealed conditions.

After the reaction was completed, the bottle was opened to expose the reaction system to air. The reaction was added dropwise to 400ml of cooled, constantly stirred petroleum ether: collecting insoluble solid in mixed solution of ethyl ether 1:1 to obtain hydrophilic long-chain NB-CDP-P (OEGMA) of terminal base bornylene₅₀-co-NHSMA₁₂)。

6) Preparing a molecular brush by ring-opening metathesis polymerization:

transferring all the required drugs into a glove box (so as to achieve helium atmosphere protection), 0.1g NB-CDP-P (MMA) obtained in step 4)₂₅-co-DMAP₁₂) Dissolved in 1ml of methylene chloride, and reacted with 4.8mg of Grubbs 3 (a Grubbs three-generation catalyst) at room temperature with exclusion of light for 30 min. Further, a solution containing 0.36g of NB-CDP-P (OEGMA) was added to the system₅₀-co-NHSMA₁₂) 2ml of DCM was reacted further for 5h at 30 ℃ in the dark.

After the reaction was completed, 0.3ml of ethyl vinyl ether was added to quench the reaction. Dropping the reaction solution into 200ml of cooled diethyl ether which is continuously stirred, and collecting insoluble solids to obtain a brush-shaped polymer (molecular brush);

at this time, z₁And z₂In a ratio of 1: 1.

7) TEMPO loading on Brush polymers:

0.1g of the brush polymer of step 6) and 22mg of 4-amino-TEMPO were dissolved in 2ml of a dichloromethane solution, deoxygenated by introducing nitrogen for 15 minutes, dissolved and mixed uniformly. 1ml of a dichloromethane solution containing DCC (0.2g) and 1ml of a dichloromethane solution containing DMAP (0.01g) were added under ice-bath conditions. The ice bath was removed and the reaction was carried out at room temperature for 36 h. After the reaction is finished, dropwise adding the reaction solution into 400ml of cooled and constantly stirred solution of diethyl ether and petroleum ether in a ratio of 1:1, and collecting insoluble solids to obtain the dual-catalytic-function molecular brush.

8) Self-assembly of the molecular brush:

0.01g of the bifunctional molecular brush obtained in the seventh step was sufficiently dissolved in 1ml of tetrahydrofuran, and 1ml of ultrapure water was slowly dropped into the above system, followed by stirring for 1 hour. And blowing the mixed solution by using nitrogen until the tetrahydrofuran is completely evaporated to obtain the nano micelle solution of 10 mg/ml. (as described in figures 2 and 3).

Experiment I, testing the catalytic effect:

0.012g of the reaction substrate 1, 0.008g of the reaction substrate 2, 0.01g of sodium hypochlorite and 0.5ml of a 10mg/ml nanomicelle solution (obtained in example 1) were thoroughly mixed at room temperature, 0.5ml of ultrapure water was added thereto, and the mixture was vigorously stirred at room temperature (at a rotation speed of 900r/min, reaction time was as shown in Table 1 below). After the reaction was completed, 2ml of diethyl ether was added to extract the small molecular organic matter. The yield of substrate was analyzed by GC-MS. The nano micelle is left in the water phase, and is washed and recovered by cold ether (20 ml of ether at 0-5 ℃) through high-temperature centrifugation (rotating speed of 80 ℃ and 10000 r/min).

The catalytic effects of the nanomicelles of the examples and the corresponding supported catalysts were measured as shown in table 1 below. It can be seen that the oxidation of alcohol (substrate 1) and Knoevenagel condensation reaction can be directly catalyzed by the tandem brush polymer one-bath to produce the product (as depicted in figure 1). Greatly simplifying the production process and obtaining good catalytic effect.

TABLE 1 Nano-micelle tandem catalyzed alcohol oxidation and Knoevenagel condensation reaction

Experiment two, recovery experiment:

adding 0.5ml of ultrapure water into the nano-micelle obtained by washing and recovering the experimental group 2 of the first experiment so as to replace '0.5 ml of nano-micelle solution with the concentration of 10 mg/ml' in the first experiment; the remainder of the experiments were carried out according to experiment one, experiment set 2, and the yield was 91%.

Example 2, the "NHSMA" in step 3) and step 5) of example 1 was changed to either:

1,1,1,3,3, 3-hexafluoroisopropyl acrylate (HFIPA), pentafluorophenol acrylate (PFPF), succinimidyl N-acrylate (NHSA); the rest is equivalent to embodiment 1.

The experiment was performed according to experiment group 2 of experiment one, using the nano-micelle solution obtained in example 2 instead of the nano-micelle solution obtained in example 1, and the yields were 96%, and 95%, respectively.

Example 3 reacting the organic base of step 4) of example 1 with "DMAP-NH₂"to DABCO-NH₂(N-Aminotriethylenediamine), DABCO-NH₂The molar amount of (A) is the same as DMAP-NH₂And the rest is equivalent to example 1.

The nano-micelle solution obtained in example 3 was used in place of the nano-micelle solution obtained in example 1, and an experiment was performed according to experiment group 2 of experiment one, and the yield was 93%.

Comparative example 1, step 4) was loaded with DMAP-NH₂Respectively loading any one of the following: piperazine, piperidine and pyridine, the dosage is kept unchanged; the rest is equivalent to embodiment 1.

The nano-micelle solution obtained in example 1 was replaced with the 3 nano-micelle solutions obtained in comparative example 1, and the experiment was performed according to experiment group 2 of experiment one, because piperazine/piperidine/pyridine has weak basicity and poor catalytic effect, the yield of 3 was about 65-70%.

Comparative example 2, example 1, step 4) was loaded with DMAP-NH₂Instead, it was loaded with 4-amino-TEMPO in step 7), the rest being identical to example 1.

Namely, with respect to example 1:

eliminating the raw material NB-CDP-P (MMA) in the step 4) and the step 6)₂₅-co-DMAP₁₂) Modified to NB-CDP-P (MMA)₂₅-co-NHSMA₁₂) The rest is unchanged;

step 7) is changed into: 0.1g of the brush polymer from step 6), 0.02g of DMAP-NH₂And 22mg of 4-amino-TEMPO in 5ml of a dichloromethane solution, deoxygenated by introducing nitrogen for 15 minutes, dissolved and mixed well. 2ml of a dichloromethane solution containing DCC (0.4g) and 2ml of a dichloromethane solution containing DMAP (0.02g) were added under ice-bath conditions. The ice bath was removed and the reaction was carried out at room temperature for 36 h. Reaction ofAt the end, the reaction was added dropwise to 500ml of a cooled, constantly stirred solution of diethyl ether and petroleum ether 1:1, and the insoluble solid was collected.

The resultant was directly subjected to step 8).

The nano-micelle solution obtained in comparative example 2 was used in place of the nano-micelle solution obtained in example 1, and an experiment was performed according to experiment set 2 of experiment one, and the yield was 57%.

Comparative example 3 preparation of NB-CDP-P (OEGMA) in step 6) of example 1₅₀-co-NHSMA₁₂) The mass of (A) is changed from 0.36g to 0.2 g; namely z₁And z₂In a ratio of 0.6: 1; the rest is equivalent to embodiment 1.

The nano-micelle solution obtained in comparative example 3 was used in place of the nano-micelle solution obtained in example 1, and an experiment was performed according to experiment group 2 of experiment one, and the yield was 42%. This is because the hydrophobic segment is too long to effectively form micelles in the aqueous phase, resulting in a less efficient catalytic reaction.

Finally, it is also noted that the above-mentioned lists merely illustrate a few specific embodiments of the invention. It is obvious that the invention is not limited to the above embodiments, but that many variations are possible. All modifications which can be derived or suggested by a person skilled in the art from the disclosure of the present invention are to be considered within the scope of the invention.