Preparation method of isoterpinen-4, 8-epoxide

Abstract

The invention relates to a method for synthesizing an isoterpinen-4, 8 epoxide. Specifically, the invention provides the preparation method of the isoterpinen-4, 8-epoxide, and the method comprises the following steps: (1) mixing isoterpinene with an organic solvent to obtain a solution A; (2) mixing hydrogen peroxide with EDTA-2Na (Ethylene Diamine Tetraacetic Acid-2Na) to obtain a solution B; and (3) mixing the solution A prepared in the step (1) and the solution B prepared in the step (2), reacting, separating the reaction liquid in an oil-water separator to obtain an oil phase, and separating to obtain the isoterpinen-4, 8-epoxide. The isoterpinene-4, 8-epoxide prepared by the preparation method of the isoterpinene-4, 8-epoxide disclosed by the invention has the advantages of excellent purity, excellent yield and excellent conversion rate.

Description

Technical Field

[0001] The invention relates to the field of chemical industry, and in particular to a method for synthesizing terpinolene-4,8-epoxide. Background Art

[0002] Terpinen-4-ol is a chemical product with high added value, which is often used in the preparation of high-grade flavors and fragrances, as a drug intermediate, or in the research and development of disinfectants, preservatives, herbicides and biopesticides. However, due to the high cost and shortage of natural plants as raw materials for supplying terpinen-4-ol, the industry often prepares terpinen-4,8-epoxide by epoxidation of terpinenene, and then further reacts the terpinen-4,8-epoxide to obtain terpinen-4-ol. However, the epoxidation of terpinenene to prepare terpinen-4,8-epoxide is a bottleneck in the production route of terpinen-4-ol. Therefore, how to effectively realize the epoxidation of terpinenene to prepare terpinen-4,8-epoxide becomes a difficulty.

[0003] Therefore, there is a need in the art to develop an effective method for preparing terpinolene-4,8-epoxide by epoxidation of terpinolene. Summary of the invention

[0004] The object of the present invention is to provide a method for preparing terpinolene-4,8-epoxide. The terpinolene-4,8-epoxide prepared by the method has excellent purity, yield and conversion rate.

[0005] The first aspect of the present invention provides a method for preparing terpinolene-4,8-epoxide, the method comprising:

[0006] (1) mixing terpinene with an organic solvent to obtain a solution A;

[0007] (2) mixing hydrogen peroxide and EDTA-2Na to obtain solution B;

[0008] (3) The solution A prepared in step (1) and the solution B prepared in step (2) are mixed, and after the reaction, the reaction solution enters an oil-water separator for separation to obtain an oil phase, and terpinolene-4,8-epoxide is separated.

[0009] Preferably, in step (1), the organic solvent comprises dichloromethane.

[0010] Preferably, in step (1), the mass ratio of terpinolene to the organic solvent is 1:(1-5), preferably 1:(2-4), more preferably 1:(2.5-3.5), more preferably 1:(2.8-3.2), and most preferably 1:3.

[0011] Preferably, the mass ratio of the hydrogen peroxide in step (2) to the terpinolene in step (1) is (3-8):(5-10), preferably (4-6):(6-8), more preferably (4.5-5.5):(6.5-7.5), more preferably (4.8-5.2):(6.8-7.2), and most preferably 5:7.

[0012] Preferably, the amount of EDTA-2Na added in step (2) is 0.01-0.5% of the mass of terpinolene in step (1), preferably 0.02-0.2%, more preferably 0.05-0.15%, more preferably 0.08-0.12%, and most preferably 0.1%.

[0013] Preferably, in step (2), the hydrogen peroxide comprises 40-60 wt % hydrogen peroxide, preferably 45-55 wt % hydrogen peroxide, more preferably 48-52 wt % hydrogen peroxide, and most preferably 50 wt % hydrogen peroxide.

[0014] Preferably, in step (3), the reaction temperature is 60-70°C, preferably 63-68°C, and more preferably 65°C.

[0015] Preferably, in step (3), the reaction pressure is 0.1-0.8 MPa, preferably 0.2-0.6 MPa, more preferably 0.3-0.5 MPa, and most preferably 0.4 MPa.

[0016] Preferably, in step (3), the reaction temperature is 20-40s, preferably 25-35s, more preferably 28-32s, and most preferably 30s.

[0017] Preferably, in step (3), solution A prepared in step (1) and solution B prepared in step (2) are respectively pumped into a static mixer to mix solution A and solution B, and then enter the microchannel reactor to react.

[0018] Preferably, in the step (3), the flow rate of solution A prepared in step (1) is controlled at 20-40 ml / min (preferably 25-35 ml / min, more preferably 29-33 ml / min, optimally 31 ml / min) and the flow rate of solution B prepared in step (2) is controlled at 2-20 ml / min (preferably 5-15 ml / min, more preferably 8-12 ml / min, optimally 10 ml / min), and they are respectively pumped into a static mixer to mix solution A and solution B, and then enter the microchannel reactor for reaction.

[0019] Preferably, in the step (3), the oil phase is washed with an aqueous sodium sulfite solution and water to separate and obtain terpinolene-4,8-epoxide.

[0020] Preferably, the sodium sulfite aqueous solution comprises 3-7 wt % sodium sulfite aqueous solution, preferably 4-6 wt % sodium sulfite aqueous solution, more preferably 5 wt % sodium sulfite aqueous solution.

[0021] Preferably, in the step (3), the obtained oil phase is separated after removing the solvent to obtain terpinolene-4,8-epoxide.

[0022] Preferably, in the step (3), the obtained oil phase is separated by distillation to obtain terpinolene-4,8-epoxide.

[0023] Preferably, the distillation is carried out in a distillation tower.

[0024] Preferably, the distillation comprises one or more characteristics selected from the group consisting of:

[0025] (i) the vacuum degree at the top of the distillation tower is 0.5-2.0 KPa, preferably 0.5-1.5 KPa, more preferably 0.8-1.2 KPa, and most preferably 1.0 KPa;

[0026] (ii) the bottom temperature of the distillation tower is 130-150°C, preferably 135-145°C, more preferably 138-142°C, and most preferably 140°C; and / or

[0027] (iii) The reflux ratio of the distillation tower is 3-20:1, preferably 5-15:1, more preferably 9-11:1, and most preferably 10:1.

[0028] It should be understood that within the scope of the present invention, the above-mentioned technical features of the present invention and the technical features specifically described below (such as embodiments) can be combined with each other to form new or preferred technical solutions. DETAILED DESCRIPTION

[0029] The present invention develops a method for preparing terpinene-4,8-epoxide, wherein the method epoxidizes terpinene to generate terpinene-4,8-epoxide. The terpinene-4,8-epoxide prepared by the method of the present invention has excellent purity, yield and conversion rate. Therefore, the method of the present invention can effectively realize the synthesis of terpinene-4,8-epoxide by epoxidizing terpinene.

[0030] the term

[0031] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0032] As used herein, the terms "including", "comprising", and "containing" are used interchangeably and include not only open definitions, but also semi-closed and closed definitions, including "consisting of", "consisting essentially of".

[0033] As used herein, the term "EDTA-2Na" is also known as Ethylenediaminetetraacetic acid disodium salt.

[0034] As used herein, the term "terpinolene" has the following structure:

[0035]

[0036] As used herein, the term "terpinolene-4,8-epoxide" has the following structure:

[0037]

[0038] method

[0039] The present invention provides a method for preparing terpinolene-4,8-epoxide, the method comprising:

[0040] (1) mixing terpinene with an organic solvent to obtain a solution A;

[0041] (2) mixing hydrogen peroxide and EDTA-2Na to obtain solution B;

[0042] (3) The solution A prepared in step (1) and the solution B prepared in step (2) are mixed, and after the reaction, the reaction solution enters an oil-water separator for separation to obtain an oil phase, and terpinolene-4,8-epoxide is separated.

[0043] Specifically, the preparation method of terpinolene-4,8-epoxide described in the present invention is as described above in the first aspect of the present invention.

[0044] The main technical effects of the present invention include:

[0045] The invention develops a method for preparing terpinolene-4,8-epoxide. The terpinolene-4,8-epoxide prepared by the method has excellent purity, yield and conversion rate.

[0046] The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0047] Example

[0048] "EDTA-2Na" is also known as Ethylenediaminetetraacetic acid disodium salt.

[0049] The structure of terpinolene is as follows:

[0050]

[0051] The structure of terpinolene-4,8-epoxide is as follows:

[0052]

[0053] Example 1

[0054] This embodiment 1 provides a preparation of terpinolene-4,8-epoxide, wherein the terpinolene-4,8-epoxide is prepared by the following method:

[0055] (1) Terpinolene and dichloromethane are mixed in a mass ratio of 1:3 to obtain solution A.

[0056] (2) 50 wt % hydrogen peroxide and EDTA-2Na are mixed to obtain solution B, wherein the mass ratio of hydrogen peroxide to terpinene in step (1) is 5:7, and the amount of EDTA-2Na added is 0.1% of the mass of terpinene in step (1).

[0057] (3) The flow rate of solution A prepared in step (1) is controlled at 31 ml / min, and the flow rate of solution B prepared in step (2) is controlled at 10 ml / min. The two solutions are respectively pumped into a static mixer to mix solution A and solution B, and then enter a microchannel reactor. After reacting for 30 seconds at 65° C. and a pressure of 0.4 MPa, the reaction solution enters an oil-water separator for separation. The separated oil phase is washed with a 5 wt % sodium sulfite aqueous solution and water. The oil phase components are detected by gas chromatography to obtain a terpinolene-4,8-epoxide content of 82.3%, a terpinolene content of 4.5%, and a conversion rate of 95%. The solution is then distilled in a distillation tower. The top vacuum degree of the distillation tower is 1.0 KPa, the bottom temperature is 140° C., and the reflux ratio is controlled to be 10:1 to obtain terpinolene-4,8-epoxide with a purity of 98.7%.

[0058] Comparative Example 1

[0059] (1) Terpinolene and dichloromethane are mixed in a mass ratio of 1:3 to obtain solution A.

[0060] (2) 50 wt % hydrogen peroxide and EDTA-2Na are mixed to obtain solution B, wherein the mass ratio of hydrogen peroxide to terpinene in step (1) is 5:7, and the amount of EDTA-2Na added is 0.1% of the mass of terpinene in step (1).

[0061] (3) The flow rate of solution A prepared in step (1) is controlled at 31 ml / min, and the flow rate of solution B prepared in step (2) is controlled at 10 ml / min. The two solutions are respectively pumped into a static mixer to mix solution A and solution B, and then into a microchannel reactor to react for 30 seconds at 45° C. and a pressure of 0.35 MPa. The reaction liquid enters an oil-water separator for separation. The separated oil phase is washed with a 5 wt % sodium sulfite aqueous solution and water. The oil phase components are detected by gas chromatography, and the content of terpinene-4,8-epoxide is 62%, the content of terpinene is 24%, and the conversion rate is 73.3%.

[0062] Comparative Example 2

[0063] (1) Terpinolene and dichloromethane are mixed in a mass ratio of 1:3 to obtain solution A.

[0064] (2) 50 wt % hydrogen peroxide and EDTA-2Na are mixed to obtain solution B, wherein the mass ratio of hydrogen peroxide to terpinene in step (1) is 5:7, and the amount of EDTA-2Na added is 0.1% of the mass of terpinene in step (1).

[0065] (3) The flow rate of solution A prepared in step (1) is controlled at 31 ml / min, and the flow rate of solution B prepared in step (2) is controlled at 10 ml / min. The two solutions are respectively pumped into a static mixer to mix solution A and solution B, and then enter a microchannel reactor to react at 65° C. and 0.5 MPa for 50 seconds. The reaction liquid enters an oil-water separator for separation. The separated oil phase is washed with a 5 wt % sodium sulfite aqueous solution and water. The oil phase components are detected by gas chromatography, and the content of terpinene-4,8-epoxide is 75%, the content of terpinene is 2.3%, the conversion rate is 97.4%, and over-oxidation occurs.

[0066] Comparative Example 3

[0067] (1) Terpinolene and dichloromethane are mixed in a mass ratio of 1:3 to obtain solution A.

[0068] (2) 50 wt % hydrogen peroxide and EDTA-2Na are mixed to obtain solution B, wherein the mass ratio of hydrogen peroxide to terpinene in step (1) is 5:7, and the amount of EDTA-2Na added is 0.1% of the mass of terpinene in step (1).

[0069] (3) The flow rate of solution A prepared in step (1) is controlled at 31 ml / min, and the flow rate of solution B prepared in step (2) is controlled at 10 ml / min. The two solutions are respectively pumped into a static mixer to mix solution A and solution B, and then into a microchannel reactor to react at 65° C. and 0.5 MPa for 20 seconds. The reaction liquid enters an oil-water separator for separation. The separated oil phase is washed with a 5 wt % sodium sulfite aqueous solution and water. The oil phase components are detected by gas chromatography, and the content of terpinolene-4,8-epoxide is 67.5%, the content of terpinolene is 19.8%, and the conversion rate is 77.8%.

[0070] Comparative Example 4

[0071] (1) Terpinolene and dichloromethane are mixed in a mass ratio of 1:2 to obtain solution A.

[0072] (2) 50 wt % hydrogen peroxide and EDTA-2Na are mixed to obtain solution B, wherein the mass ratio of hydrogen peroxide to terpinene in step (1) is 5:7, and the amount of EDTA-2Na added is 0.1% of the mass of terpinene in step (1).

[0073] (3) The flow rate of solution A prepared in step (1) is controlled at 31 ml / min, and the flow rate of solution B prepared in step (2) is controlled at 10 ml / min. The two solutions are respectively pumped into a static mixer to mix solution A and solution B, and then into a microchannel reactor to react at 65° C. and 0.5 MPa for 30 seconds. The reaction liquid enters an oil-water separator for separation. The separated oil phase is washed with a 5 wt % sodium sulfite aqueous solution and water. The oil phase components are detected by gas chromatography, and the content of terpinene-4,8-epoxide is 61.5%, the content of terpinene is 25.3%, and the conversion rate is 71.9%.

[0074] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for preparing terpinene-4,8-epoxide, characterized in that: The method includes: (1) mixing terpinene with an organic solvent to obtain a solution A; (2) mixing hydrogen peroxide and EDTA-2Na to obtain solution B; (3) The solution A prepared in step (1) and the solution B prepared in step (2) are mixed, and after the reaction, the reaction solution enters an oil-water separator for separation to obtain an oil phase, and terpinolene-4,8-epoxide is separated.

2. The method according to claim 1, characterized in that In the step (1), the organic solvent includes dichloromethane.

3. The method according to claim 1, characterized in that The mass ratio of the hydrogen peroxide in the step (2) to the terpinene in the step (1) is (3-8):(5-10), preferably (4-6):(6-8), more preferably (4.5-5.5):(6.5-7.5), more preferably (4.8-5.2):(6.8-7.2), and most preferably 5:

7.

4. The method according to claim 1, characterized in that The amount of EDTA-2Na added in step (2) is 0.01-0.5% of the mass of terpinene in step (1), preferably 0.02-0.2%, more preferably 0.05-0.15%, more preferably 0.08-0.12%, and most preferably 0.1%.

5. The method according to claim 1, characterized in that In the step (2), the hydrogen peroxide comprises 40-60 wt % hydrogen peroxide, preferably 45-55 wt % hydrogen peroxide, more preferably 48-52 wt % hydrogen peroxide, and most preferably 50 wt % hydrogen peroxide.

6. The method according to claim 1, characterized in that In the step (3), the reaction temperature is 60-70°C, preferably 63-68°C, and more preferably 65°C.

7. The method according to claim 1, characterized in that In the step (3), the reaction pressure is 0.1-0.8 MPa, preferably 0.2-0.6 MPa, more preferably 0.3-0.5 MPa, and most preferably 0.4 MPa.

8. The method according to claim 1, characterized in that In the step (3), the reaction temperature is 20-40s, preferably 25-35s, more preferably 28-32s, and most preferably 30s.

9. The method according to claim 1, characterized in that In the step (3), the oil phase is washed with an aqueous sodium sulfite solution and water to separate and obtain terpinolene-4,8-epoxide.

10. The method according to claim 1, characterized in that In the step (3), the obtained oil phase is separated by distillation to obtain terpinene-4,8-epoxide; The distillation comprises selecting one or more characteristics from the group consisting of: (i) the vacuum degree at the top of the distillation tower is 0.5-2.0 KPa, preferably 0.5-1.5 KPa, more preferably 0.8-1.2 KPa, and most preferably 1.0 KPa; (ii) the bottom temperature of the distillation tower is 130-150°C, preferably 135-145°C, more preferably 138-142°C, and most preferably 140°C; and / or (iii) The reflux ratio of the distillation tower is 3-20:1, preferably 5-15:1, more preferably 9-11:1, and most preferably 10:1.

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