CN110092722B - Method for catalytic synthesis of 4-acyl aralkyl phenol derivative - Google Patents

Abstract

The invention discloses a method for catalyzing synthesis of 4-acyl aralkyl phenol derivatives. Under the catalysis of modified attapulgite solid acid, the process of catalyzing p-cumylphenol and acylating reagent to generate 4-acyl aralkylphenol derivatives, the solid catalyst is attapulgite clay, and natural attapulgite is The clay is thermally treated at a certain temperature, and the acidity of attapulgite is regulated by Lewis acid at different temperatures to catalyze p-cumylphenol and acylating reagent to generate 4-acylaralkylphenol derivatives. The reaction has the characteristics of mild reaction conditions, low cost of the used catalyst, environmental friendliness, simple process, easy separation and reusability of the catalyst and the like.

Description

A kind of method for catalyzing synthesis of 4-acyl aralkyl phenol derivatives

technical field

The invention belongs to the field of synthesis of small molecular compounds, and relates to a method for catalyzing synthesis of 4-acyl aralkyl phenol derivatives.

Background technique

Triphenolic compounds are mainly used as raw materials for epoxy resins, polycarbonate resins and other polymer compounds, and can also be used as photoresists and additives for such polymer compounds. 4-Acyl aralkylphenol derivatives are important intermediates in the synthesis of triphenolic compounds.

At present, the main methods for synthesizing 4-acyl aralkyl phenol derivatives, which are precursors of triphenolic compounds, are known to be the synthesis of isopropenyl acetophenone and phenols. (Patent Document: Japanese Patent Laid-Open No. 62-084035). It is well known that the raw material isopropenyl acetophenone is not only active and difficult to store, but also has a high price and a low synthesis yield. And the known synthesis method using p-cumyl phenol compound as raw material (patent document: CN 107011124 A), uses aluminum trichloride as catalyst to catalyze the reaction between p-cumyl phenol compound and acylating reagent. In this method, the catalyst is unfavorable for recovery, and the waste water after the reaction contains a large amount of aluminum salts, which causes certain harm to the environment. Therefore, it is necessary to seek a green and efficient catalyst for the synthesis of 4-acylaralkylphenol derivatives.

SUMMARY OF THE INVENTION

The object of the present invention is to provide an economical and green preparation method of 4-acyl aralkyl phenol derivatives, which is environmentally friendly, mild in conditions, and reusable catalyst, so as to overcome the serious pollution in the prior art, the large amount of waste liquid, and the need for post-processing Complexity and other disadvantages.

Another object of the present invention is to provide a green and efficient catalyst for catalyzing the synthesis of 4-acyl aralkyl phenol derivatives.

For achieving the above object, the technical scheme adopted in the present invention is as follows:

A method for catalyzing synthesis of 4-acyl aralkyl phenol derivatives, using modified attapulgite solid acid as a catalyst to catalyze p-cumyl phenol and an acylating agent to generate 4-acyl aralkyl phenol derivatives, wherein, The modified attapulgite solid acid catalyst is obtained by using attapulgite as a precursor, modifying its acidity with protonic acid or Lewis acid, and calcining and activating it at 100-1000 ℃; the reaction route is as follows:

The acylating reagent is selected from

In the formula, X is a halogen atom. X=Cl, Br

When preparing the catalyst, the Lewis acid is preferably tetrabutyl titanate, tin tetrachloride pentahydrate, ammonium metatungstate, tantalum pentachloride, and the weight ratio of Lewis acid to attapulgite is preferably 1:1-20, The firing activation time is preferably 1 hour to 24 hours. Further preferably, the Lewis acid is tin tetrachloride pentahydrate, and the calcination activation time is 2-5 hours.

The acylating reagents are preferably acetyl chloride, acetyl bromide, acetic acid and acetic anhydride. Acetyl chloride is further preferred.

The molar ratio of p-cumylphenol to the acylating agent is preferably 1:2-4, more preferably 1:3.

The reaction solvent is preferably dichloromethane, chloroform, toluene, and dichloroethane; preferably dichloromethane.

The reaction temperature for the catalytic synthesis of 4-acyl aralkylphenol derivatives is preferably 0-30° C., and the reaction time is preferably 2-4 hours.

The weight ratio of p-cumylphenol to the modified attapulgite solid acid catalyst is preferably 1:1-2, more preferably 1:1.3-1.7, and most preferably 1:1.5.

As a further preference of the method of the present invention, a reaction solvent and a catalyst are added to the reaction vessel, an acylating reagent is added dropwise at room temperature, and after the dropwise addition is completed, stirring for a few minutes, p-cumylphenol is added, and after the addition is completed, the reaction is maintained and stirred, and separated and filtered. Solid catalyst, the filtrate is poured into ice water, the reaction solvent is added to extract, layered, washed with water, and the solvent is distilled off by rotary evaporation to obtain the target product 4-acyl aralkyl phenol derivative, and the filtered solid catalyst can be used again after activation.

Preferably, in the reaction, the acylating reagent, acetyl chloride, is dropwise at 10°C, and after the dropwise addition, the best reaction is at 25°C, and the optimum reaction time is 2.5h.

Preferably, the catalyst is obtained by using attapulgite clay as a precursor, acid modification of the catalyst by Lewis acid, and calcination and activation at 300-600°C.

Preferably, the solid catalyst for immobilized tin oxide, the weight ratio of tin tetrachloride pentahydrate to attapulgite is 1:15, the stirring temperature is 45 ° C, and the stirring temperature is 48 h, and the best preparation is obtained by baking at 500 ° C in a muffle furnace. .

The present invention has the following advantages:

1. The solid acid catalyst used in the present invention has high activity, good selectivity to products, is environmentally friendly, insoluble in water, easy to separate, and has low catalyst cost.

2 Using the natural mineral attapulgite as a catalyst precursor is not only economical and easy to obtain, but also can enhance the added value of mineral resources and promote the development and utilization of mineral resources in my country.

3. The catalyst is simple to separate, can be reused, and the catalytic efficiency is not significantly reduced.

Detailed ways

The following examples will further illustrate the present invention in detail, but the content of the present invention is not limited thereto.

Example 1

A preparation method for catalyzing 4-acyl aralkyl phenol derivatives, comprising the following steps:

Catalyst preparation: take 1.5 g of attapulgite clay, add 20 mL of prepared 1M sulfuric acid, stir at room temperature for 52 h, let stand for aging for 12 h, centrifuge to separate the lower sediment, then wash with water until the pH becomes neutral, dry at 60 °C, grind, After that, it was dried at 110 °C for 2 h in a vacuum drying oven, and then slowly heated to 300 °C in a muffle furnace for activation for 3 h to obtain the desired catalyst, which was a sulfuric acid-treated attapulgite clay catalyst.

Acylation: Add 30 mL of dichloromethane as a solvent to a 100 mL round-bottomed flask, take 0.32 g of the above catalyst, and put it into the round-bottomed flask. The round-bottomed flask was placed in a magnetic stirring bar, placed in an oil bath at 10°C for thermal insulation and stirring, and 0.213 mL of acylating reagent acetyl chloride was slowly added dropwise to the round-bottomed flask. P-cumylphenol was slowly added to the round-bottomed flask, the temperature was raised to 25°C, and the reaction was stirred and refluxed for 2.5h.

Filtration: The above system is separated under reduced pressure, and the solid catalyst is separated from the liquid of the reaction system.

Washing with water: Pour the filtered liquid into a pear-shaped separatory funnel, add 100 ml of ice water to shake and wash. After standing, 30 ml of dichloromethane was added for extraction. The layers were left to stand, and the lower layer solution was separated.

Rotary evaporation: The above lower layer solution was rotary evaporated under reduced pressure to remove the solvent. Only the esterified product was obtained, but the target product 4-acylaralkylphenol was not obtained.

Example 2-3

Only the protonic acid added in the catalyst preparation was changed, and the rest were the same as in Example 1. The results are shown in Table 1

Table 1

It can be seen from Examples 1-3 that protic acids are not suitable for preparing catalysts for catalyzing 4-acylaralkylphenol derivatives.

Example 4

A preparation method for catalyzing 4-acyl aralkyl phenol derivatives, comprising the following steps:

Catalyst preparation: take 1.5 g of attapulgite clay, add 10 mL of prepared 0.1 g tin tetrachloride pentahydrate aqueous solution, stir at 45°C for 48 h, let stand for aging for 12 h, dry in a blast drying oven for 12 h, and then put it in a muffle furnace The desired catalyst was obtained by slowly heating up to 500 °C for 3 h and activation.

Acylation: add 30 ml of dichloromethane as a solvent to a 100 ml round-bottomed flask, take 0.32 g of the above catalyst, and put it into the round-bottomed flask. Put the magnetic stirring bar into the round-bottomed flask, place it in an oil bath at 10°C and keep stirring, take 0.213ml (3mol) of acylating reagent acetyl chloride, and slowly add it dropwise to the round-bottomed flask. 0.2121g of p-cumylphenol was slowly added to the round-bottom flask, the temperature was raised to 25°C, and the reaction was stirred and refluxed for 2.5h.

Filtration: The above system is separated under reduced pressure, and the solid catalyst is separated from the liquid of the reaction system.

Washing with water: Pour the filtered liquid into a pear-shaped separatory funnel, add 100 ml of ice water and shake for washing. After standing, 30 ml of dichloromethane was added for extraction. The layers were left to stand, and the lower layer solution was separated.

Rotary evaporation: The above solution was rotary evaporated under reduced pressure to remove the solvent. The target product was obtained in 84% yield. The target product was confirmed to be 4-acylaralkylphenol by NMR spectroscopy.

¹ H NMR (400MHz, CDCl ₃ )δ(ppm) 1.69(s, 6H, 2×CH ₃ ), 2.28(s, 3H, OCOCH ₃ ), 2.57(s, 3H, CH ₃ CO), 6.99(d, J=5.76, 2H, ArH), 7.20 (d, J=5.64, 2H, ArH), 7.32 (d, J=5.48, 2H, ArH), 7.87 (d, J=5.84, 2H, ArH)

Catalyst reactivation: The solid obtained in the filtration step was washed with distilled water, and activated in a muffle furnace at 500° C. for three hours for use.

Examples 5-7

Only the Lewis acid added in the catalyst preparation was changed, and the rest were the same as in Example 4. The results are shown in Table 2.

Table 2

It can be seen from Examples 4-7 that the catalysts prepared by using tin tetrachloride pentahydrate modified attapulgite clay are significantly superior to other Lewis acids in terms of selectivity and catalytic efficiency.

Examples 8-10

Only the quality of attapulgite clay in catalyst preparation was changed, and the mass ratio of Lewis acid to attapulgite clay was adjusted, and the rest were the same as in Example 4. The results are shown in Table 3:

table 3

Examples 11-13

Only the solvent in the acylation reaction was changed, and the rest were the same as in Example 4. The results are shown in Table 4:

Table 4

Examples 14-16

Only the acylation reagent in the acylation reaction was changed, and the rest were the same as those in Example 4. The results are shown in Table 5:

table 5

Examples 17-18

Only the consumption of acetyl chloride in the acylation reaction was changed, and the rest were the same as in Example 4. The results are shown in Table 6:

Table 6

Examples 19-21

Only the reaction temperature in the acylation reaction was changed, and the rest were the same as those in Example 4. The results are shown in Table 7:

Table 7

Examples 22-24

Only the reaction time in the acylation reaction was changed, and the rest were the same as in Example 4. The results are shown in Table 8:

Table 8

Examples 25-28

The recovered catalyst was used, and the rest were the same as in Example 4. The results are shown in Table 9:

Table 9

It can be seen from the above examples that the present invention uses attapulgite clay as a catalyst precursor, and is modified with different acids to realize the reaction of p-cumylphenol and acylating reagent to generate 4-acylaralkylphenol derivatives. Compared with the Lewis acid catalysis process, the catalysis process is green and pollution-free, and the catalyst can be reused, showing a good industrial application prospect.

Although the embodiments of the present inventions have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the inventions.

Claims (8)

1. A method for catalytically synthesizing a 4-acyl aralkyl phenol derivative is characterized in that modified attapulgite solid acid is used as a catalyst, p-cumylphenol and an acylation reagent are catalyzed to generate the 4-acyl aralkyl phenol derivative, wherein the modified attapulgite solid acid catalyst is obtained by using attapulgite clay as a precursor, modifying the attapulgite clay with acid by stannic chloride pentahydrate, and roasting and activating at the temperature of 300-600 ℃; the weight ratio of the tin tetrachloride pentahydrate to the attapulgite clay is 1:1-20, and the roasting activation time is 2 hours to 5 hours; the reaction route is as follows:

the acylating agent is selected from

Wherein X is Br or Cl.

2. The method for the catalytic synthesis of a 4-acylaralkylphenol derivative according to claim 1, wherein the reaction solvent for the catalytic synthesis of the 4-acylaralkylphenol derivative is selected from the group consisting of dichloromethane, chloroform, toluene and dichloroethane.

3. The method for the catalytic synthesis of a 4-acylaralkylphenol derivative according to claim 2, wherein the reaction solvent for the catalytic synthesis of the 4-acylaralkylphenol derivative is selected from dichloromethane.

4. The method for the catalytic synthesis of 4-acylaralkylphenol derivatives according to claim 1, wherein the reaction temperature is 0-30 ℃ and the reaction time is 1-6 hours.

5. The process for the catalytic synthesis of 4-acylaralkylphenol derivatives according to claim 1, characterized in that the molar ratio of p-cumylphenol to acylating agent is 1: 2-3.

6. The catalytic synthesis method of 4-acyl aralkyl phenol derivatives according to claim 1, wherein the weight ratio of the p-cumylphenol to the modified attapulgite solid acid catalyst is 1: 1-2.

7. The catalytic synthesis method of 4-acyl aralkyl phenol derivatives of claim 6, wherein the weight ratio of the p-cumylphenol to the modified attapulgite solid acid catalyst is 1: 1.5-1.7.

8. The method for catalytically synthesizing a 4-acylaralkylphenol derivative according to any one of claims 1 to 7, characterized in that a reaction solvent and a catalyst are added to a reaction vessel, an acylating agent is dropped at room temperature, the mixture is stirred for several minutes after the dropping, p-cumylphenol is added, the mixture is stirred at a constant temperature after the addition, the solid catalyst is separated and filtered, the filtrate is poured into ice water, the reaction solvent is added for extraction, the mixture is layered, washed with water, and the solvent is evaporated by rotation to obtain the target product, namely the 4-acylaralkylphenol derivative, and the filtered solid catalyst can be reused after being activated.