A method for synthesizing o-sec-butylphenol

Abstract

The application belongs to the field of chemical synthesis, and particularly relates to a synthesis method of o-sec-butyl phenol. Organic mixed phenyl aluminum is used as a catalyst, 1-butene is used as an alkylation reagent, and the 1-butene is reacted with phenol to synthesize o-sec-butyl phenol. The reaction pressure is 1.6-6.0 MPa, the reaction temperature is 90-150 DEG C, the reaction time is 1-10 h, the molar ratio of phenol to 1-butene is 1:0.6-0.9, and the dosage of the phenyl aluminum catalyst is 0.5-1.5% of the mass of the phenol. The catalyst has good activity and selectivity. The alkylation product is subjected to rectification, the unreacted phenol and 1-butene can be continuously used as the reaction raw material for synthesizing o-sec-butyl phenol after recovery, the conversion rate of the phenol is greater than or equal to 95%, the one-way yield of o-sec-butyl phenol is greater than or equal to 80%, and the overall yield is greater than or equal to 90%. The o-sec-butyl phenol is synthesized through the reaction route, the process flow is simple, the reaction energy consumption is low, the by-products are few, the subsequent rectification is simple, the product quality is stable, and the industrial production is facilitated.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of chemical synthesis, and particularly relates to a synthesis method of o-sec-butyl phenol. BACKGROUND

[0002] The o-sec-butyl phenol has the following chemical formula:

[0003]

[0004] The o-sec-butyl phenol is an important intermediate for synthesizing the carbamate pesticide sec-butyl phenol, and is also an intermediate for the herbicide glyphosate and the acaricide dienochlor. In the pharmaceutical industry, the o-sec-butyl phenol is often used as a disinfectant and a preservative. In recent years, with the rapid development of the petrochemical industry at home and abroad, the market for the synthesis of a new type of high-efficiency polymerization inhibitor DNBP (4,6-dinitro-o-sec-butyl phenol) from the o-sec-butyl phenol as a raw material and nitric acid as a nitrating agent through a one-step catalytic method is increasingly broad.

[0005] At present, the industrial production route of the o-sec-butyl phenol is to use phenol and 2-butene as raw materials, use phenol aluminum as a catalyst, use the catalyst in an amount of greater than or equal to 3%, and react at a temperature of 180-255 DEG C and a pressure of 1.0-1.8 MPa to obtain the o-sec-butyl phenol. Since the selectivity of the catalyst used is not high, and the reaction temperature is high, the obtained alkylated reaction product contains the para-sec-butyl phenol, di-sec-butyl phenol, tri-sec-butyl phenol and other by-products, and the content of the by-products is not low (more than 10%). These by-products are difficult to separate and utilize, which greatly increases the production cost of the o-sec-butyl phenol and greatly affects the purity of the product.

[0006] Therefore, how to effectively overcome the problems in the prior art and provide a synthesis method of the o-sec-butyl phenol more suitable for industrial application has become a problem to be solved in the field. SUMMARY

[0007] The present application provides a synthesis method of the o-sec-butyl phenol, which uses an organic mixed phenol aluminum as a catalyst, 1-butene as an alkylating agent, and phenol to synthesize the o-sec-butyl phenol. The reaction pressure is 1.6-6.0 MPa, the reaction temperature is 90-150 DEG C, the reaction time is 1-10 h, the molar ratio of the phenol to the 1-butene is 1:0.6-0.9, and the amount of the phenol aluminum catalyst is 0.5-1.5% of the mass of the phenol. The catalyst used has good activity and selectivity. The alkylated product is subjected to rectification, and the unreacted phenol and 1-butene can be recycled and used as raw materials for synthesizing the o-sec-butyl phenol. The conversion rate of the phenol is greater than or equal to 95%, the one-way yield of the o-sec-butyl phenol is greater than or equal to 80%, and the overall yield is greater than or equal to 90%. The synthesis of the o-sec-butyl phenol through the reaction route has the advantages of a simple process flow, low reaction energy consumption, few by-products, simple subsequent rectification, stable product quality and convenient industrial production.

[0008] The biggest difference of the present application compared with the prior art is that the catalyst used is an organic mixed phenyl aluminum salt. The phenyl aluminum salt catalyst helps to improve the selectivity of the ortho compound. More importantly, the mixed phenyl aluminum salt catalyst used in the present application is added with o-sec-butyl phenol. In the synthesis of o-sec-butyl phenol, the inventors found that the addition of o-sec-butyl phenol in the synthesis process of the organic phenyl aluminum catalyst unexpectedly improved the yield of o-sec-butyl phenol in the second step reaction, indicating that the activity and selectivity of the catalyst in the present application were effectively improved compared with the ordinary phenyl aluminum catalyst.

[0009] In addition, another feature of the present application is the use of high pressure reaction. The alkylation reaction pressure of the present application is 1.6-6.0 MPa. The main alkylation reaction pressure on the market is below 0.5 MPa, and the highest pressure is 1.5 MPa. At this time, the reaction is a gas-liquid reaction. If the reaction temperature exceeds 180℃, it is a gas phase reaction, and the reaction effect is not good. From the perspective of mass transfer of reaction materials, the present application increases the reaction pressure of the system (higher than 1.5 MPa). At this pressure, the material mixing is more uniform, which is more conducive to the reaction. At the same time, from the perspective of device investment and reaction demand, the reaction pressure is controlled below 6.0 MPa. Corresponding to the above reaction pressure is the reaction temperature. The alkylation reaction temperature of the present application is 90-150℃. The reaction temperature is low, which is not conducive to the alkylation reaction. If the temperature is higher than 150℃, a large amount of sec-butyl phenol, di-sec-butyl phenol and even tri-sec-butyl phenol by-products will be generated. These by-products are difficult to separate from o-sec-butyl product, and the separation cost is increased.

[0010] Based on the above improvements, the specific technical scheme of the present application is as follows:

[0011] A synthesis method of o-sec-butyl phenol, using an organic mixed phenyl aluminum as a catalyst, 1-butene as an alkylation reagent, and phenol to synthesize o-sec-butyl phenol; the reaction pressure is 1.6-6.0 MPa, the reaction temperature is 90-150℃, the reaction time is 1-10 h, the molar ratio of phenol to 1-butene is 1:0.6-0.9, and the amount of phenyl aluminum catalyst is 0.5-1.5% of the mass of phenol;

[0012] Preferably, the alkylation reaction pressure is preferably 2.0-4.0 MPa;

[0013] Preferably, the alkylation reaction temperature is 100-140℃, more preferably 110-125℃.

[0014] The organic mixed phenol aluminum catalyst is synthesized under the following reaction conditions: the molar ratio of mixed phenol to aluminum is 1:0.001-0.005, the mass fraction of o-sec-butyl phenol in phenol is 0.3-1.8%, and the reaction temperature is 120-150°C.

[0015] As mentioned above, the mixed phenol is a mixture of phenol and o-sec-butyl phenol. In the above reaction, the reaction can be started when the system temperature is raised to above 120°C. Since the reaction is exothermic, the reaction is completed when the temperature of the reaction system is no longer increased.

[0016] Preferably, the organic mixed phenol aluminum catalyst is synthesized under the following reaction conditions: the molar ratio of mixed phenol to aluminum is 1:0.002-0.005, the mass fraction of o-sec-butyl phenol in phenol is 0.4-1.6%, and the reaction temperature is 120-150°C.

[0017] More preferably, the organic mixed phenol aluminum catalyst is synthesized under the following reaction conditions: the molar ratio of mixed phenol to aluminum is 1:0.002-0.004, the mass fraction of o-sec-butyl phenol in phenol is 0.5-1.5%, and the reaction temperature is 130-150°C.

[0018] In the above manner, the mixed phenol aluminum catalyst is formed after a certain amount of o-sec-butyl phenol is added to phenol. The o-sec-butyl phenol aluminum catalyst has stronger acidity, which can improve the activity of the catalyst. Meanwhile, the shielding effect of the o-sec-butyl phenol aluminum catalyst is stronger, which can improve the selectivity of the catalyst and reduce the formation of 2,4-di-sec-butyl phenol, 2,6-di-sec-butyl phenol and tri-sec-butyl products.

[0019] The reaction time of the above alkylation reaction is 1-10h. If the reaction time is too short, the conversion rate of the material is low and the yield of the product is low. If the reaction time is too long, the by-products of the reaction increase, which reduces the yield of the product. Preferably, the reaction time of the alkylation reaction is 2-8h, and more preferably, the reaction time is 3-6h.

[0020] The phenol to 1-butene molar ratio of the above alkylation reaction is 1:0.6-0.9. If the phenol to 1-butene molar ratio is below 0.6, a large amount of phenol is not converted, which reduces the yield of the product. If the phenol to 1-butene molar ratio is greater than 0.9, the amount of sec-butyl phenol and di-sec-butyl phenol by-products increases. If the phenol to 1-butene molar ratio is above 1.5, di-sec-butyl phenol is the dominant product (the content of di-sec-butyl phenol in the product is above 60%) and tri-sec-butyl phenol is formed. Further, the phenol to 1-butene molar ratio of the alkylation reaction is 1:0.7-0.9, and more preferably, the phenol to 1-butene molar ratio is 1:0.7-0.8.

[0021] The amount of phenol aluminum catalyst used in the present application is 0.5-1.5% of the mass of phenol, because the catalytic activity and selectivity of the mixed phenol aluminum catalyst of the present application are more excellent, the amount of catalyst is reduced compared with the phenol aluminum catalyst of the industrial route (the amount of catalyst used in industrial production is generally greater than 3%); preferably, the amount of phenol aluminum catalyst used in the alkylation reaction is 0.6-1.3% of the mass of phenol, more preferably 0.8-1.2%.

[0022] Compared with the prior art, the above technical solutions of the present application have the following advantages: ① The system reaction of the present application realizes liquid phase reaction by controlling pressure conditions, which is more uniform than the gas phase reaction or gas-liquid mixed reaction of the phenol alkylation reaction in the current industrial production route or other inventions, the mass transfer effect is more ideal, and the phenol conversion rate is higher; ② The organic mixed phenol aluminum catalyst is selected, which greatly improves the reaction selectivity and effectively improves the yield of the target product o-sec-butylphenol; ③ The reaction temperature is lower than that of the current industrial production route, which greatly reduces the generation of alkylation by-products and reduces the energy consumption of product separation, thereby reducing the production cost of the product.

[0023] In summary, in the synthesis method of the present application, the phenol conversion rate is ≥95%, the one-way yield of o-sec-butylphenol is ≥80%, and the overall yield is ≥90%. By the reaction route for synthesizing o-sec-butylphenol, the process flow is simple, the reaction energy consumption is low, the by-products are few, the subsequent rectification is simple, the product quality is stable, and the industrial production is convenient. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be described below in a clear and complete manner. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor belong to the scope of protection of the present application.

[0025] The present application provides a synthesis method of o-sec-butylphenol, which uses organic mixed phenol aluminum as a catalyst and 1-butene as an alkylation reagent to react with phenol to synthesize o-sec-butylphenol; the reaction pressure is 1.6-6.0 MPa, the reaction temperature is 90-150℃, the reaction time is 1-10 h, the molar ratio of phenol to 1-butene is 1:0.6-0.9, and the amount of phenol aluminum catalyst is 0.5-1.5% of the mass of phenol.

[0026] The above-mentioned organic mixed phenol aluminum catalyst is synthesized under the reaction conditions of a molar ratio of mixed phenol to aluminum of 1:0.001-0.0.005, o-sec-butylphenol accounting for 0.3-1.8% of the mass of phenol, and a reaction temperature of 120-150℃.

[0027] The present application will be further described in detail through specific embodiments as follows:

[0028] Example 1

[0029] A synthesis method of o-sec-butyl phenol, the specific steps are as follows:

[0030] (1) Synthesis of organic mixed phenyl aluminum catalyst

[0031] After adding 340.25 g of phenol, 1.52 g of o-sec-butyl phenol and 0.15 g of aluminum powder into a 1L high-pressure reactor, stirring was started, and then the temperature was slowly increased to 120°C to start the reaction. When the reaction temperature increased to 150°C and the temperature no longer increased, the reaction was stopped, and then the temperature was decreased to about 50°C to obtain the organic mixed phenyl aluminum catalyst.

[0032] (2) Synthesis of o-sec-butyl phenol

[0033] After the reaction was completed, 123.5 g of 1-butene was continuously introduced into the above high-pressure reactor, nitrogen was introduced to control the pressure to 1.6 MPa, the reaction temperature was controlled to 90°C, and the reaction was stopped after 6 h.

[0034] Example 2

[0035] A synthesis method of o-sec-butyl phenol, the specific steps are as follows:

[0036] (1) Synthesis of organic mixed phenyl aluminum catalyst

[0037] After adding 340.85 g of phenol, 4.58 g of o-sec-butyl phenol and 0.35 g of aluminum powder into a 1L high-pressure reactor, stirring was started, and then the temperature was slowly increased to 150°C to start the reaction. When the reaction temperature increased to 170°C and the temperature no longer increased, the reaction was stopped, and then the temperature was decreased to about 50°C to obtain the organic mixed phenyl aluminum catalyst.

[0038] (2) Synthesis of o-sec-butyl phenol

[0039] After the reaction was completed, 182.5 g of 1-butene was continuously introduced into the above high-pressure reactor, nitrogen was introduced to control the pressure to 4.0 MPa, the reaction temperature was controlled to 150°C, and the reaction was stopped after 3 h.

[0040] Example 3

[0041] A synthesis method of o-sec-butyl phenol, the specific steps are as follows:

[0042] (1) Synthesis of organic mixed phenyl aluminum catalyst

[0043] After adding 340.33 g of phenol, 1.25 g of o-sec-butyl phenol and 0.25 g of aluminum powder into a 1L high-pressure reactor, stirring was started, and then the temperature was slowly increased to 120°C to start the reaction. When the reaction temperature increased to 150°C and the temperature no longer increased, the reaction was stopped, and then the temperature was decreased to about 50°C to obtain the organic mixed phenyl aluminum catalyst.

[0044] (2) Synthesis of o-sec-butyl phenol

[0045] After the reaction is completed, 160.7 g of 1-butene is continuously introduced into the above high-pressure reaction kettle, nitrogen is introduced to control the pressure to 3 MPa, the reaction temperature is controlled to 120°C, and after 4 h of reaction, the reaction is stopped.

[0046] Example 4

[0047] A method for synthesizing o-sec-butyl phenol, the specific steps are as follows:

[0048] (1) Synthesis of organic mixed phenyl aluminum catalyst

[0049] In a 1L high-pressure reaction kettle, 340.54 g of phenol, 1.98 g of o-sec-butyl phenol, and 0.31 g of aluminum powder are added, and then stirring is started, and the temperature is slowly raised to 140°C to start the reaction. When the reaction temperature rises to 160°C and the temperature no longer rises, the reaction is stopped, and then the temperature is lowered to about 50°C to obtain an organic mixed phenyl aluminum catalyst.

[0050] (2) Synthesis of o-sec-butyl phenol

[0051] After the reaction is completed, 146.5 g of 1-butene is continuously introduced into the above high-pressure reaction kettle, nitrogen is introduced to control the pressure to 3.5 MPa, the reaction temperature is controlled to 110°C, and after 5 h of reaction, the reaction is stopped.

[0052] Comparative Example 1

[0053] In the catalyst synthesis process, o-sec-butyl phenol is not added, and only phenyl aluminum catalyst is used instead of the organic mixed phenyl aluminum catalyst of the present application, and the remaining reaction steps and conditions are carried out according to the method of Example 2.

[0054] Comparative Example 2

[0055] In the catalyst synthesis process, o-sec-butyl phenol is not added, and only phenyl aluminum catalyst is used instead of the organic mixed phenyl aluminum catalyst of the present application, and the reaction temperature for the synthesis of o-sec-butyl phenol in the second step is 180°C, and the remaining reaction steps and conditions are carried out according to the method of Example 2.

[0056] Comparative Example 3

[0057] The reaction pressure is 0.5 MPa, and the remaining reaction steps and conditions are carried out according to the method of Example 2.

[0058] Comparative Example 4

[0059] The reaction pressure is 0.5 MPa, the molar ratio of phenol to alkene is 1:1.5 (the amount of phenol added is 340.79 g, and the amount of 1-butene added is 305.45 g), and the remaining reaction steps and conditions are carried out according to the method of Example 2.

[0060] The results of the alkylation products of different embodiments and comparative examples are shown in Table 1.

[0061] Table 1

[0062]

[0063] As can be seen from the results in the table, when phenol aluminum is used alone as the catalyst (comparative example 1), the conversion rate of phenol decreases, and the amount of para-sec-butyl phenol increases, indicating that the selectivity of the catalytic activity of the mixed phenol aluminum catalyst used in the application is improved;

[0064] When phenol aluminum is used alone as the catalyst, the synthesis reaction temperature of ortho-sec-butyl phenol is increased to 180℃ (comparative example 2), and more by-products such as para-sec-butyl phenol and di-sec-butyl phenol are generated, resulting in a significant decrease in the yield of the target product ortho-sec-butyl phenol;

[0065] When the reaction pressure is reduced to 0.5 MPa (comparative example 3), the conversion rate of ortho-sec-butyl phenol decreases, and the yield of the target product decreases;

[0066] When the reaction pressure is 0.5 MPa and the molar ratio of phenol to alkene is 1:1.5 (comparative example 4), the main product in the product is di-sec-butyl phenol, and the target product ortho-sec-butyl phenol is 2.67%;

[0067] However, by using the organic mixed phenol aluminum catalyst and the reaction conditions of the application, the conversion rate of phenol is high, the content of by-products is low, and the yield of the target product ortho-sec-butyl phenol is effectively improved.

[0068] The above is only a preferred embodiment of the application, and it should be noted that for those skilled in the art, without departing from the principles of the application, a number of improvements and refinements can be made, and these improvements and refinements should also be considered within the scope of protection of the application.

Claims

1. A method for synthesizing o-sec-butylphenol, characterized in that: o-sec-butylphenol was synthesized by reacting phenol with an organic mixed phenol-aluminum catalyst and 1-butene as an alkylating agent. The reaction pressure was 2.0-4.0 MPa, the reaction temperature was 110-125℃, the reaction time was 3-6 h, the molar ratio of phenol to 1-butene was 1:0.7-0.8, and the amount of phenol-aluminum catalyst was 0.8-1.2% of the mass of phenol. The organic mixed phenol-aluminum catalyst is synthesized under the following reaction conditions: a molar ratio of mixed phenol to aluminum of 1:0.002-0.004, o-sec-butylphenol accounting for 0.5-1.5% of the mass of phenol, and a reaction temperature of 130-150℃; the mixed phenol is a mixture of phenol and o-sec-butylphenol.

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