CN109053390B - Preparation method of 25, 27-diisopropoxy-26, 28-dihydroxy calix [4] arene - Google Patents
Preparation method of 25, 27-diisopropoxy-26, 28-dihydroxy calix [4] arene Download PDFInfo
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Abstract
The invention relates to the field of organic chemical synthesis, in particular to a preparation method of 25, 27-diisopropoxy-26, 28-dihydroxy calix [4] arene. The preparation method provided by the invention comprises the following steps: under the protection of nitrogen, sequentially adding 25,26,27, 28-tetrahydroxycalix [4] arene, potassium carbonate and potassium iodide into an acetone solvent, heating and stirring; adding bromoisopropane into the reaction solution, and refluxing for 24 h; and after the reaction is finished, carrying out reduced pressure concentration, extracting the residual liquid after the reduced pressure concentration by using an extracting agent, washing an organic phase by using pure water to be neutral, adding anhydrous magnesium sulfate for drying, filtering to obtain a filtrate, concentrating the filtrate under reduced pressure, adding methanol with 2 times of volume into the residual liquid of the filtrate, separating out a large amount of white precipitate, filtering, washing a filter cake twice by using methanol, and drying to obtain a target product. The method has the advantages of low requirements on reaction raw materials, low reaction temperature, low price of bromoisopropane and low toxicity, improves the activity of potassium carbonate by using potassium iodide as secondary catalysis, and can be used for industrial large-scale production.
Description
Technical Field
The invention belongs to the technical field of organic synthesis, and particularly relates to a preparation method of 25, 27-diisopropoxy-26, 28-dihydroxy calix [4] arene.
Background
Calix [4] arenes are macrocyclic oligomers linked by methylene groups, formed by condensation of para-substituted phenol units with aldehydes under basic conditions. Since the end of the 70 s, the american chemist c.david Gutsche first indicated that these compounds have a circular array of cavities of adjustable size, and that calixarene chemistry was unprecedentedly developed when they could potentially be used as molecular acceptors or as mimetic enzymes.
Various derivatives such as esters, ketones, amides, quinones, ethers and the like formed by modifying the upper and lower edges of calixarene can be used in various fields such as biochemistry and medicine. In particular, studies on enzyme simulation have made the synthesis of the upper edge functionalized calixarene ether derivatives important.
Cs and Sr are the main radioactive elements with long service life and high heat release in the high-level waste. The half-life of Cs in the high-level waste is 30 years, and the physical and chemical instability caused by the heat generation of the Cs is considered to be one of the most dangerous elements influencing the safe disposal of the high-level waste by glass curing. If Cs can be separated, the purposes of reducing the glass solidification volume and shortening the time for cooling waste materials and the storage life of waste materials can be achieved, and due to the reduction of heat release, the method directly contributes to the sheet detection operation and cost saving during geological disposal. The calixarene crown ether shows super-strong selective matching capability to cesium ions, is easy to recover, has less secondary waste, and can be continuously operated by a solvent extraction method. The 25, 27-diisopropoxy cup [4] crown-6 BPC6 for short has good selective adsorption performance on radioactive Cs ions in the high-level radioactive waste liquid, and shows unique application prospect in removing Cs from the high-level radioactive waste. And the 25, 27-diisopropoxy-26, 28-dihydroxy calix [4] arene is a key intermediate for synthesizing the BPC6, and the yield and the purity of the arene have a key influence on the difficulty and the cost of purifying the BPC 6.
Currently 25, 27-diisopropoxy-26, 28-dihydroxy cup [4]]In the preparation process of the aromatic hydrocarbon, acetonitrile is selected as a solvent, so that the preparation method is high in price, high in toxicity, high in reaction temperature, high in equipment requirement and high in danger coefficient if the preparation method is used for large-scale production. In addition, the acetonitrile solvent selected in the existing production process needs to use P2O5Reflux dewatering, K2CO3Grinding is required and the material is calcined in a muffle furnace at 500 ℃ for 5h, and the remaining reagents are analytically pure. The selected iodoisopropane is also an expensive raw material, has high toxicity and great harm to human bodies, and cannot realize industrial amplification.
Disclosure of Invention
Aiming at the problems, the invention aims to provide a preparation method of 25, 27-diisopropoxy-26, 28-dihydroxycalix [4] arene, which aims to solve the problems that the requirements on raw materials and equipment are high and the industrial amplification cannot be realized in the existing preparation process, thereby reducing the input cost in the preparation process and realizing the industrial scale production.
A method for preparing 25, 27-diisopropoxy-26, 28-dihydroxy calix [4] arene, comprising the following steps:
step a: under the protection of nitrogen, 25,26,27, 28-tetrahydroxycalix [4] arene, potassium carbonate and potassium iodide are sequentially added into an acetone solvent, heated and stirred to ionize raw materials.
Step b: adding bromoisopropane into the reaction liquid in the step a, heating to 56 ℃, and refluxing for 24 h.
Step c: and c, after the reaction is finished, concentrating the reaction liquid in the step b under reduced pressure, extracting residual liquid after the concentration under reduced pressure by using an extracting agent, washing an organic phase by using pure water to be neutral, adding anhydrous magnesium sulfate for drying, filtering to obtain filtrate, concentrating the filtrate under reduced pressure, adding methanol with 2 times of volume into the residual liquid of the filtrate, separating out a large amount of white precipitate, filtering, washing a filter cake twice by using methanol, and drying to obtain a target product.
Wherein, the boiling point of the bromoisopropane is 59.41 ℃, if acetonitrile is used as a solvent, the bromoisopropane is vaporized in a reflux reaction, the reaction can not be completely carried out, and a monoalkylated product and a dialkylated product simultaneously exist in the product; in addition, when acetonitrile is used for reaction at 56 ℃, only monoalkylated product can be obtained, and the reaction temperature is insufficient, so that the activation energy is insufficient, and the monoalkylated product can not be reacted with bromoisopropane to generate dialkylated product. The solvent in the invention is acetone, and the acetone plays the following roles in the reaction: firstly, the dissolution effect is realized, so that reactants are fully ionized; keeping the reaction temperature constant; and thirdly, the heating is uniform. The boiling point of acetone is 56 deg.C, and acetone reflux does not vaporize isopropyl bromide, so that the reaction is more complete.
In a preferred embodiment of the present invention, the temperature in step a is 45-55 ℃ and the reaction time is 0.5-2 h.
In a preferred embodiment of the present invention, the molar ratio of 25,26,27, 28-tetrahydroxycalix [4] arene to potassium carbonate in step a is 1: 1-2.
In a preferred embodiment of the present invention, the molar ratio of 25,26,27, 28-tetrahydroxycalix [4] arene to potassium iodide in step a is 1: 1-2.
In a preferred embodiment of the present invention, the molar ratio of 25,26,27, 28-tetrahydroxycalix [4] arene to bromoisopropane in step a is 1: 4-5.
In a preferred embodiment of the present invention, the extractant in step c is a mixed solvent of hydrochloric acid and dichloromethane, wherein the concentration of hydrochloric acid is 2mol/L, and the volume ratio of hydrochloric acid to dichloromethane is 1:1
Compared with the prior art, the invention has the following beneficial effects:
1. in the preparation method provided by the invention, the adopted reaction raw materials have low requirements, and the bromo-isopropyl is cheap and low in toxicity compared with the iodo-isopropyl; in the invention, acetone is used as a solvent, the price of the acetone is lower than that of acetonitrile, the toxicity of the acetonitrile is far greater than that of the acetone, and the acetone is selected, so that the cost in production can be reduced, the requirement on equipment is lower, and the influence on the environment and production personnel is smaller; in addition, the reaction temperature in the invention is low, the requirement on production equipment is low, and the energy consumption in the preparation process is low.
2. The raw materials adopted in the invention can be used for production without special treatment, other raw materials required for production can be chemically pure, the yield and purity of the obtained product are higher, and industrial large-scale production can be completely realized.
3. In the invention, potassium iodide is used for secondary catalysis to improve the activity of potassium carbonate, and specifically, potassium ions in potassium iodide can be replaced by iodine ions in potassium carbonate so as to improve the activity of the catalyst and improve the efficiency of the whole reaction.
Drawings
FIG. 1 shows the effect of ionization temperature on the yield according to the present invention;
FIG. 2 shows the effect of ionization time on yield according to the present invention;
FIG. 3 shows the effect of the amount of potassium iodide on the yield according to the present invention.
Detailed Description
The invention is further illustrated by the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it is to be understood that various changes or modifications may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present application.
Example 1
Under the protection of nitrogen, 20g (0.047mol) of 25,26,27, 28-tetrahydroxycalix [4] arene, 13.01g (0.094mol) of potassium carbonate solid, 7.81g (0.047mol) of potassium iodide solid and 300ml of acetone are added into a 500ml four-neck flask, the temperature is increased to 50 ℃, the mixture is stirred for 1h to ionize the raw materials, 23.16g (0.188mol) of bromoisopropane is added, and the mixture is heated to 56 ℃ to carry out reflux reaction for 24 h.
The reaction was monitored by thin layer chromatography, after completion of the reaction, acetone was concentrated under reduced pressure, and the residue was purified by dissolving in 400ml of a mixed solvent [ V (2mol/L hydrochloric acid): v (dichloromethane) ═ 1:1]Extracting, washing an organic phase to be neutral by pure water, drying by anhydrous magnesium sulfate, filtering, concentrating dichloromethane under reduced pressure, adding methanol with 2 times volume of the residual liquid to separate out a large amount of white precipitate, filtering, washing a filter cake twice by the methanol, and drying to obtain white powder 20.4g, m.p. 168.6-173 ℃, wherein the yield is 85.16 percent, and the purity is more than 95 percent; h NMR. delta.: 517(d, 6H, CH3), 3.664, 4.319(t, 4H, ArCH)2Ar)，4.354(d，H，CH in Pr)，6.704，6.722(t，2H，ArOH)；6.914,6.933(d，4H，ArH)，8.166(s，H，ArOH)。
Example 2
This example was conducted under substantially the same reaction conditions as example 1, except that the ionization temperature in this example was 40 ℃ and the yield of the obtained product was 74%.
Example 3
This example was carried out under substantially the same reaction conditions as example 1, with the greatest difference that the stirring time was 0.5h and the yield of the product obtained was 82.6%.
Example 4
The reaction conditions in this example were about the same as those in example 1, except that the stirring time in this example was 1.5 hours, and the yield of the obtained product was 84.45%.
Example 5
The reaction conditions in this example were about the same as those in example 1, except that the stirring time in this example was 1.5 hours, and the yield of the obtained product was 83.26%.
Example 6
This comparative example was conducted under substantially the same reaction conditions as example 1 except that in this comparative example, potassium iodide was used in an amount of 3.9g (0.024mol) at a molar ratio of starting material to potassium iodide of 2:1 to give a product in a yield of 81.35%.
Example 7
This example was conducted under substantially the same reaction conditions as in example 1, except that the amount of potassium iodide used in this example was 11.71g (0.071mol), and the molar ratio between the starting material and potassium iodide was 1: 1.5, the yield of the product obtained is 85.6%.
Example 8
The present example was substantially the same as example 1 except that potassium iodide was used in an amount of 15.61g (0.094mol) and the molar ratio of the raw material to potassium iodide was 1: 2, the yield of the product obtained is 85.6%.
Example 9
The specific information of the industrial raw materials used in this example is as follows:
25,26,27, 28-tetrahydroxycalix [4] arene: the Chengduli JING science and technology Limited company produces a crude product with the purity of 97.3 percent;
potassium carbonate: the product of Henan Zhengyao chemical products Limited company is first-grade product with the purity of 99 percent;
potassium iodide: the Henan Lanxiang chemical raw material is produced by a chemical material limited company, and has the pharmaceutical grade and the purity of 99 percent;
bromo-isopropane: the purity of the salt city Longsheng chemical industry Co., Ltd is 99 percent;
acetone: sumeida chemical company, Youji, Yangzhou, with 99% purity.
Under the protection of nitrogen, 20g (0.047mol) of 25,26,27, 28-tetrahydroxycalix [4] arene, 13.01g (0.094mol) of potassium carbonate solid, 7.81g (0.047mol) of potassium iodide solid and 300ml of acetone are added into a 500ml four-neck flask, the temperature is raised to 50 ℃, stirring is carried out for 1h, 23.16g (0.188mol) of bromoisopropane is added, and reflux reaction is carried out for 24 h.
The reaction was monitored by thin layer chromatography, after completion of the reaction, acetone was concentrated under reduced pressure, and the residue was purified by dissolving in 400ml of a mixed solvent [ V (2mol/L hydrochloric acid): extracting V (dichloromethane) ═ 1:1], washing an organic phase to be neutral by pure water, drying by anhydrous magnesium sulfate, filtering, concentrating dichloromethane under reduced pressure, adding 2 times of methanol into residual liquid, separating out a large amount of white precipitate, filtering, washing a filter cake twice by methanol, drying to obtain white powder, and recrystallizing by using a mixed solvent of 1.5 times of dichloromethane and 2 times of ethanol in equivalent volume of product mass to obtain a product with the purity of more than 95%, wherein the final yield is 83.06%.
Example 10
This example was conducted under the same reaction conditions as example 1 except that potassium carbonate was used in an amount of 31.22g (0.188mol) and the product was obtained in 85.72% yield.
Example 11
This example was conducted under the same reaction conditions as example 1 except that potassium carbonate was used in an amount of 28.95g (0.235mol) and the yield of the obtained product was 86.05%.
Comparative example 1
This comparative example was about the same as example 1 except that the reaction temperature was 35 ℃ and the yield of the obtained product was 68%.
Comparative example 2
This comparative example was about the same as example 1 except that the reaction temperature was 40 deg.c and the yield of the obtained product was 74%.
Comparative example 3
This example was conducted under the same reaction conditions as those of example 1 except that the stirring was not conducted and the yield of the obtained product was 81%
Comparative example 4
The reaction conditions of this comparative example were about the same as those of example 1, except that in this comparative example, acetonitrile of the same volume was used as a solvent to obtain a product, and the presence of both a monoalkylated product and a dialkylated product was determined by thin layer chromatography.
Analysis of results
First, influence of ionization temperature on yield
The effect of ionization temperature on yield is shown in fig. 1, with reference to fig. 1 in combination with experimental procedures and experimental data of example 1, example 2, comparative example 1, and comparative example 2.
The dissociation process is an endothermic reaction, the temperature is increased to facilitate the dissociation of the two phenolic hydroxyl groups on 25 and 27 in 25,26,27, 28-tetrahydroxycalix [4] arene, the same ionization time is kept for 1h, and if the ionization temperature is lower than 45 ℃, the ionization is incomplete. The reaction yield was 74% when the ionization temperature was 40 ℃; the reaction yield was 68% when the ionization temperature was 35 ℃; the reaction yield was 81% when the ionization temperature was 55 ℃, so the optimum ionization temperature was 45 ℃ to 50 ℃.
Second, influence of ionization time on yield
The effect of ionization time on yield is shown in fig. 2, with reference to fig. 2 in combination with the experimental procedures and experimental data of example 3, example 4, example 5 and comparative example 3.
Effect of ionization time on yield the present invention compares the difference in yield between non-ionized, half-hour, one-half-hour, and two hours, with 81% yield for non-ionized direct thermal reflux, 82.6% yield for half-hour, 85.16% yield for one-hour, 84.85% yield for one-half-hour, and 83.26% yield for two hours, so the optimal ionization time is one hour. In addition, the ionization time is too long, water in the reaction system increases, oxygen anions formed by dissociation of phenolic hydroxyl groups of the monoalkylated product form hydrogen bonds with water molecules in the reaction system, and the yield of dialkylated product is thus reduced.
Influence of potassium iodide amount on yield
The effect of potassium iodide on yield is shown in fig. 3, with reference to fig. 3, and with reference to the experimental procedures and experimental data of examples 6, 7 and 8. When KI is used in an amount of 0.5 times equivalent, the yield is 81.35%, but when KI is used in an amount of 1 time equivalent, 1.5 times equivalent, and 2 times equivalent, the yield is the same, so that 1 time equivalent is the most preferable amount of KI.
The above description is only a preferred embodiment of the present invention, and not intended to limit the present invention, and the scope of the present invention is defined by the appended claims, and all changes that come within the meaning and range of equivalency of the specification are therefore intended to be embraced therein.
Claims (2)
- A process for preparing 25, 27-diisopropoxy-26, 28-dihydroxy calix [4] arene, characterized by comprising the following steps:step a: under the protection of nitrogen, sequentially adding 25,26,27, 28-tetrahydroxycalix [4] arene, potassium carbonate and potassium iodide into an acetone solvent, heating and stirring to ionize raw materials; the ionization temperature is 45-55 ℃, and the reaction time is 0.5-2 h; the molar ratio of 25,26,27, 28-tetrahydroxycalix [4] arene to potassium carbonate is 1: 1-2; the molar ratio of 25,26,27, 28-tetrahydroxycalix [4] arene to potassium iodide is 1: 1-2;step b: b, adding bromoisopropane into the reaction solution in the step a, heating to 56 ℃, and refluxing for 24 hours; the molar ratio of 25,26,27, 28-tetrahydroxycalix [4] arene to bromoisopropane is 1: 4-5;step c: and c, after the reaction is finished, concentrating the reaction liquid in the step b under reduced pressure, extracting residual liquid after the concentration under reduced pressure by using an extracting agent, washing an organic phase by using pure water to be neutral, adding anhydrous magnesium sulfate for drying, filtering to obtain filtrate, concentrating the filtrate under reduced pressure, adding methanol with 2 times of volume into the residual liquid of the filtrate, separating out a large amount of white precipitate, filtering, washing a filter cake twice by using methanol, and drying to obtain a target product.
- 2. The preparation method of claim 1, wherein the extractant in the step c is a mixed solvent of hydrochloric acid and dichloromethane, wherein the concentration of the hydrochloric acid is 2mol/L, and the volume ratio of the hydrochloric acid to the dichloromethane is 1: 1.
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| CN101337865A (en) * | 2008-08-11 | 2009-01-07 | 同济大学 | Method for preparing hydroxyl-containing calix[4]arene derivates |
| CN101367934A (en) * | 2008-09-25 | 2009-02-18 | 上海交通大学 | Preparation method for polyglycol modified amphipathic calixarene |
| CN101555219A (en) * | 2009-05-18 | 2009-10-14 | 同济大学 | Method for preparing carlix (4) arene derivative containing sulfur and hydroxyl groups |
| CN107075229A (en) * | 2014-10-21 | 2017-08-18 | Si集团有限公司 | Method for stabilizing the phenolic resin containing calixarenes |
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| US5926687A (en) * | 1993-04-19 | 1999-07-20 | Commissariat A L'energie Atomique | Crown calix |4| arenes, their preparation process and their use for the selective extraction of cesium and actinides |
| CN101337865A (en) * | 2008-08-11 | 2009-01-07 | 同济大学 | Method for preparing hydroxyl-containing calix[4]arene derivates |
| CN101367934A (en) * | 2008-09-25 | 2009-02-18 | 上海交通大学 | Preparation method for polyglycol modified amphipathic calixarene |
| CN101555219A (en) * | 2009-05-18 | 2009-10-14 | 同济大学 | Method for preparing carlix (4) arene derivative containing sulfur and hydroxyl groups |
| CN107075229A (en) * | 2014-10-21 | 2017-08-18 | Si集团有限公司 | Method for stabilizing the phenolic resin containing calixarenes |
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