Method for synthesizing resorcinol from 3-(2-hydroxy-2-propyl) phenol

Abstract

The invention discloses a method for synthesizing resorcinol from 3-(2-hydroxy-2-propyl) phenol, which is characterized in that Bronsted acidic ionic liquid is used as a catalyst, propylene glycol fatty acid ester is used as an auxiliary agent, and the 3-(2-hydroxy-2-propyl) phenol and hydrogen peroxide react to generate the resorcinol. According to the method, the resorcinol can be efficiently and stably produced from the 3-(2-hydroxy-2-propyl) phenol through a one-step method, and the product yield is high.

Description

Technical Field

[0001] The invention relates to a method for synthesizing resorcinol, in particular to a method for synthesizing resorcinol from 3-(2-hydroxy-2-propyl)phenol. Background Art

[0002] Resorcinol is a colorless or off-white needle-shaped crystal or powder, which is mainly used in the rubber industry, low-temperature wood adhesives, dyes and pharmaceutical industries. At present, the main methods for industrial production of resorcinol are: benzene sulfonation alkali fusion method, meta-phenylenediamine method and meta-diisopropylbenzene oxidation method. The benzene sulfonation alkali fusion method uses a large amount of sulfonating agent, the equipment is easily corroded, and the environmental pollution is relatively serious, and it is facing elimination. The meta-phenylenediamine method is highly dangerous, and related manufacturers have experienced many nitro compound explosion accidents. Only a few Japanese companies have mastered the production technology of meta-diisopropylbenzene oxidation method, and the process flow is as follows:

[0003]

[0004] In this process, m-diisopropylbenzene is oxidized by air to prepare 3-(1-hydroperoxy-1-methylethyl)-α,α-dimethylbenzyl alcohol HHP and DHP, and then DHP is cracked to produce resorcinol; at the same time, HHP will also undergo a cracking reaction to produce 3-(2-hydroxy-2-propyl)phenol, namely DCS. Since 3-(2-hydroxy-2-propyl)phenol will inevitably be produced in this reaction system, it is of great significance to study the effective utilization of 3-(2-hydroxy-2-propyl)phenol. Converting 3-(2-hydroxy-2-propyl)phenol into resorcinol can achieve high added value utilization of this by-product.

[0005] Patent CN115448818B reports a reaction in which 3-(2-hydroxy-2-propyl)phenol and hydrogen peroxide are converted into SHP in the presence of sulfuric acid, and then SHP is separated by silica gel column chromatography to obtain a pure product, and then SHP is decomposed under sulfuric acid catalysis to obtain resorcinol. The reaction process is long, there are many by-products, the intermediates need to be further separated and purified, and the reaction time is relatively long. DHP or SHP is easily decomposed into 3-(2-hydroxy-2-propyl)phenol and the like in the reaction system. In addition, under the reaction conditions of strong acid, resorcinol and meta-isopropenylphenol will undergo alkylation reaction, reducing the product yield.

[0006] Therefore, there is an urgent need in the art for a method for efficiently, conveniently and directly preparing resorcinol from 3-(2-hydroxy-2-propyl)phenol. Summary of the invention

[0007] In order to solve the above technical problems, the present invention provides a method for synthesizing resorcinol from 3-(2-hydroxy-2-propyl)phenol. The method can efficiently and stably utilize 3-(2-hydroxy-2-propyl)phenol to produce resorcinol with high product yield.

[0008] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0009] A method for synthesizing resorcinol from 3-(2-hydroxy-2-propyl)phenol is characterized by comprising a process of using Bronsted acidic ionic liquid as a catalyst and propylene glycol fatty acid ester as an auxiliary agent to react 3-(2-hydroxy-2-propyl)phenol and hydrogen peroxide to generate resorcinol.

[0010] In some embodiments, the Bronsted acidic ionic liquid is a sulfonic acid ionic liquid, preferably [TEBSA][HSO4], and the structural expression is as follows:

[0011]

[0012] The preparation method of the ionic liquid [TEBSA][HSO4] is simple and known to those skilled in the art. The raw materials thereof are widely available, cheap and easy to obtain. For details, reference may be made to the specific method in the master's thesis "Zheng Xianfeng. Process research on synthesis of N-substituted amides by Ritter reaction. Diss. Nanjing University of Science and Technology, 2010." for synthesis.

[0013] Preferably, the added amount of the Bronsted acidic ionic liquid is 0.5-2% of the mass of 3-(2-hydroxy-2-propyl)phenol.

[0014] In some embodiments, the propylene glycol fatty acid ester is at least one of the substances having the following structural expressions:

[0015]

[0016] Wherein, n is 8-16;

[0017] Preferably, the amount of the propylene glycol fatty acid ester is 1-5% of the mass of the catalyst.

[0018] In some embodiments, the molar ratio of 3-(2-hydroxy-2-propyl)phenol to hydrogen peroxide is 1:(1-10), preferably 1:(2-5);

[0019] Preferably, the mass concentration of the hydrogen peroxide is 2-30%, preferably 3-10%.

[0020] In some embodiments, the reaction temperature is 20-70°C, and the reaction time is 3-20 min.

[0021] In some embodiments, the reaction adding process is: firstly, 3-(2-hydroxy-2-propyl)phenol and the co-catalyst are mixed in an organic solvent to obtain an organic phase, the catalyst and hydrogen peroxide are mixed to obtain an aqueous phase, and then the aqueous phase is added to the organic phase for reaction.

[0022] In some embodiments, the organic solvent is a ketone, preferably one or more of acetone, methyl ethyl ketone, and methyl isobutyl ketone (MIBK).

[0023] In some embodiments, the amount of the organic solvent used is 4-25 times the mass of 3-(2-hydroxy-2-propyl)phenol.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) Resorcinol can be obtained by one-step reaction, with high reaction yield, few by-products, low cost, and suitable for industrial production;

[0026] (2) The reaction can be carried out using low-concentration hydrogen peroxide as a raw material, thereby improving the intrinsic safety level of the reaction;

[0027] (3) The introduction of additives enhances mass transfer, reduces the proportion of the intermediate product peroxide SHP in the reaction system, and directly obtains resorcinol in high yield through a one-step reaction. DETAILED DESCRIPTION

[0028] The present invention is further described below by means of specific examples. The examples described in the present invention are only used to illustrate the present invention and do not limit the scope of the present invention.

[0029] The main raw materials in the following examples of the present invention are as follows. Unless otherwise specified, other raw materials and reagents can be generally obtained through conventional commercial channels:

[0030] 3-(2-Hydroxy-2-propyl)phenol, purity 98wt%, Beijing Inotech Co., Ltd.

[0031] 1,2-Propanediol monolaurate, Nantong Haitianyuan Chemical Co., Ltd.

[0032] 1,2-Propanediol hexadecanoate, Shanghai Jinjinle Industrial Co., Ltd.

[0033] Propylene glycol monostearate, Nantong Chenrun Chemical Co., Ltd.

[0034] MIBK: Methyl isobutyl ketone, Shanghai Aladdin Biochemical Technology Co., Ltd.

[0035] Hydrogen peroxide, 27.5% aqueous solution, Luxi Chemical Co., Ltd., on this basis, the required concentration of hydrogen peroxide is routinely prepared.

[0036] Preparation method of [TEBSA][HSO4] ionic liquid:

[0037] 0.1 mol 1,4-butane sultone, 0.1 mol triethylamine and 50 mL acetonitrile were placed in a 200 mL round-bottom flask and refluxed for 10 hours. After the reaction was completed, a white solid was filtered out, washed with ethyl acetate to remove non-ionic residues, and dried in a vacuum to obtain an intermediate (yield 85%). Then, the intermediate (23.7 g, 0.1 mol) was added to a 250 mL three-necked flask, 10 mL 10 mol / L dilute sulfuric acid was added dropwise thereto, and the reaction was stirred at 80 ° C for 6 hours. After the reaction was completed, the water was evaporated to obtain NNN-triethyl-N-sulfonic acid butyl ammonium hydrogen sulfate [TEBSA][HSO4] (yield 99%).

[0038]

[0039] The detection method involved in the following embodiments of the present invention is:

[0040] (1) HPLC method

[0041] The present invention uses high performance liquid chromatography to analyze the reaction conversion rate and selectivity, and the chromatographic analysis conditions are as follows:

[0042] Instrument model: LC-6A high performance liquid chromatograph (Shimadzu)

[0043] Analytical column: CLC-SIL 150*6.0mm (Shimadzu)

[0044] Preparative column: Zorbax SIL 250*9.4mm (Zhubang)

[0045] Mobile phase: water: methanol: isopropanol: isopropylcyclohexane (60-90°C) = 15:3:3:60 (v / v)

[0046] Flow rate: 0.7ml / min

[0047] Column temperature: room temperature

[0048] UV detector (Shimadzu SPD-6AV UV-visible spectrophotometer detector) wavelength: 235 nm;

[0049] (2) Peroxide titration

[0050] Prepared hydrogen peroxide concentration detection: refer to national standards GB / T 1616-2014 and GB / T32102-2015.

[0051] (3) Calculation method of raw material conversion rate

[0052] 3-(2-hydroxy-2-propyl)phenol conversion rate = (molar amount of 3-(2-hydroxy-2-propyl)phenol feed - molar amount of 3-(2-hydroxy-2-propyl)phenol remaining in the oil phase after reaction) / molar amount of 3-(2-hydroxy-2-propyl)phenol feed * 100%

[0053] [Example 1]

[0054] Prepare 500g of MIBK solution with 4wt% 3-(2-hydroxy-2-propyl)phenol as raw material, add 1,2-propylene glycol hexadecanoic acid monoester accounting for 0.3% of the raw material mass, mix well, and add to a 2L stainless steel reactor; then, add hydrogen peroxide aqueous solution to the reactor, the addition amount is 1.2 times the molar amount of the raw material, and the hydrogen peroxide concentration is 10wt%; keep the temperature at 20°C, add [TEBSA][HSO4] to the reactor, the addition amount is 0.5% of the raw material mass, and start the reaction. After 20 minutes, the reaction solution is cooled to room temperature, oil and water are separated, the aqueous phase is extracted by MIBK to recover resorcinol, and the extract phase is mixed with the oil phase of the reaction solution, and the oil phase is determined by HPLC method for 3-(2-hydroxy-2-propyl)phenol, resorcinol, and by-product content, and the raw material conversion rate, product yield and by-product selectivity are statistically analyzed, and the results are shown in Table 1.

[0055] [Example 2]

[0056] 500g 5wt% 3-(2-hydroxy-2-propyl)phenol MIBK solution was prepared, 0.3% propylene glycol monostearate was added to the raw material, and after uniform mixing, it was added to a 2L stainless steel reactor; subsequently, an aqueous hydrogen peroxide solution was added to the reactor, the addition amount was 1.6 times the molar amount of the raw material, and the hydrogen peroxide concentration was 8wt%; the temperature was raised to 40°C, [TEBSA][HSO4] was added to the reactor, the addition amount was 1% of the raw material mass, and the reaction was started. After 8 minutes, the reaction solution was cooled to room temperature, oil and water were separated, the aqueous phase was extracted by MIBK to recover resorcinol, and the extraction phase was mixed with the reaction liquid oil phase, and the oil phase was determined by HPLC method for 3-(2-hydroxy-2-propyl)phenol, resorcinol, and by-product content, and the raw material conversion rate, product yield, and by-product selectivity were statistically analyzed, and the results are shown in Table 1.

[0057] [Example 3]

[0058] 500g 6.67wt% MIBK solution with 3-(2-hydroxy-2-propyl)phenol as raw material was configured, 0.3% propylene glycol monostearate was added to the raw material mass, and after mixing, it was added to a 2L stainless steel reactor; subsequently, an aqueous hydrogen peroxide solution was added to the reactor, the addition amount was 2 times the molar amount of the raw material, and the hydrogen peroxide concentration was 6wt%; the temperature was raised to 60°C, [TEBSA][HSO4] was added to the reactor, the addition amount was 1.5% of the raw material mass, and the reaction was started. After 6min, the reaction solution was cooled to room temperature, oil and water were separated, the aqueous phase was extracted by MIBK to recover resorcinol, and the extraction phase was mixed with the reaction liquid oil phase, and the oil phase was determined by HPLC method for 3-(2-hydroxy-2-propyl)phenol, resorcinol, and by-product content, and the raw material conversion rate, product yield and by-product selectivity were statistically analyzed, and the results are shown in Table 1.

[0059] [Example 4]

[0060] 500g of 10wt% MIBK solution with 3-(2-hydroxy-2-propyl)phenol as raw material was prepared, 0.3% of propylene glycol monostearate was added to the raw material mass, and after uniform mixing, it was added to a 2L stainless steel reactor; subsequently, an aqueous hydrogen peroxide solution was added to the reactor, the addition amount was 3 times the molar amount of the raw material, and the hydrogen peroxide concentration was 4wt%; the temperature was raised to 70°C, [TEBSA][HSO4] was added to the reactor, the addition amount was 2% of the mass of the reaction solution, and the reaction was started. After 4 minutes, the reaction solution was cooled to room temperature, oil and water were separated, the aqueous phase was extracted with MIBK to recover resorcinol, and the extraction phase was mixed with the reaction solution oil phase, and the oil phase was determined by HPLC method for 3-(2-hydroxy-2-propyl)phenol, resorcinol, and by-product content, and the raw material conversion rate, product yield, and by-product selectivity were statistically analyzed, and the results are shown in Table 1.

[0061] [Example 5]

[0062] Prepare 500g of MIBK solution with 25wt% 3-(2-hydroxy-2-propyl)phenol as raw material, add 1,2-propylene glycol hexadecanoic acid monoester accounting for 0.3% of the raw material mass, mix well, and add to a 2L stainless steel reactor; then, add hydrogen peroxide aqueous solution to the reactor, the addition amount is 5 times the molar amount of the raw material, and the hydrogen peroxide concentration is 3wt%; heat to 40°C, add [TEBSA][HSO4] to the reactor, the addition amount is 1.5% of the raw material mass, and start the reaction. After 3 minutes, the reaction solution is cooled to room temperature, oil and water are separated, the aqueous phase is extracted by MIBK to recover resorcinol, and the extract phase is mixed with the reaction liquid oil phase, and the oil phase is determined by HPLC method for 3-(2-hydroxy-2-propyl)phenol, resorcinol, and by-product content, and the raw material conversion rate, product yield and by-product selectivity are statistically analyzed. The results are shown in Table 1.

[0063] [Example 6]

[0064] Prepare 500g of MIBK solution with 10wt% 3-(2-hydroxy-2-propyl)phenol as raw material, add 1,2-propylene glycol monodecanoate accounting for 0.3% of the raw material mass, mix well, and add to a 2L stainless steel reactor; then, add hydrogen peroxide aqueous solution to the reactor, the addition amount is 10 times the molar amount of the raw material, and the hydrogen peroxide concentration is 3wt%; heat to 40°C, add [TEBSA][HSO4] to the reactor, the addition amount is 1.5% of the raw material mass, and start the reaction. After 3 minutes, the reaction solution is cooled to room temperature, oil and water are separated, the aqueous phase is extracted by MIBK to recover resorcinol, and the extract phase is mixed with the oil phase of the reaction solution, and the oil phase is determined by HPLC method for 3-(2-hydroxy-2-propyl)phenol, resorcinol, and by-product content, and the raw material conversion rate, product yield and by-product selectivity are statistically analyzed. The results are shown in Table 1.

[0065] [Example 7]

[0066] Prepare 500g of 10wt% MIBK solution with 3-(2-hydroxy-2-propyl)phenol as raw material, add 1,2-propylene glycol monodecanoate accounting for 0.3% of the raw material mass, mix well, and add to a 2L stainless steel reactor; then, add hydrogen peroxide aqueous solution to the reactor, the addition amount is 5 times the molar amount of the raw material, and the hydrogen peroxide concentration is 3wt%; heat to 40°C, add [TEBSA][HSO4] to the reactor, the addition amount is 1.5% of the raw material mass, and start the reaction. After 8 minutes, the reaction solution is cooled to room temperature, oil and water are separated, the aqueous phase is extracted by MIBK to recover resorcinol, and the extract phase is mixed with the oil phase of the reaction solution, and the oil phase is determined by HPLC to determine the content of 3-(2-hydroxy-2-propyl)phenol, resorcinol, and by-products, and the raw material conversion rate, product yield, and by-product selectivity are statistically analyzed. The results are shown in Table 1.

[0067] [Example 8]

[0068] 500g 10wt% 3-(2-hydroxy-2-propyl)phenol MIBK solution was prepared, 0.3% propylene glycol monostearate was added to the raw material, and after uniform mixing, the mixture was added to a 2L stainless steel reactor; subsequently, an aqueous hydrogen peroxide solution was added to the reactor, the addition amount was 5 times the molar amount of the raw material, and the hydrogen peroxide concentration was 3wt%; the temperature was raised to 40°C, [TEBSA][HSO4] was added to the reactor, the addition amount was 1.5% of the raw material mass, and the reaction was started. After 8 minutes, the reaction solution was cooled to room temperature, oil-water separation, the aqueous phase was extracted by MIBK to recover resorcinol, and the extraction phase was mixed with the reaction solution oil phase, and the oil phase was determined by HPLC to determine the content of 3-(2-hydroxy-2-propyl)phenol, resorcinol, and by-products, and the raw material conversion rate, product yield, and by-product selectivity were statistically analyzed, and the results are shown in Table 1.

[0069] [Comparative Example 1]

[0070] Resorcinol was synthesized in a method substantially the same as that in Example 7, except that 1,2-propylene glycol monolaurate was not added. The raw material conversion rate, product yield, and by-product selectivity were statistically analyzed, and the results are shown in Table 1.

[0071] [Comparative Example 2]

[0072] Resorcinol was synthesized in substantially the same manner as in Example 7, except that [TEBSA][HSO4] was replaced with an equal amount of 98 wt% sulfuric acid and 1,2-propylene glycol monododecanoate was not added.

[0073] Table 1. Analysis results

[0074]

[0075] In Table 1, the structural formula of the alkylation product of resorcinol and meta-isopropenylphenol is as follows:

[0076]

[0077] It can be seen from the test results in Table 1 that the synthesis method of the present invention has a raw material conversion rate of more than 96% and a product yield of more than 93%, and the content of typical by-products is extremely low.

[0078] The above is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this field can make several improvements and supplements without departing from the method of the present invention. These improvements and supplements should also be regarded as the scope of protection of the present invention.

Claims

1. A method for synthesizing resorcinol from 3-(2-hydroxy-2-propyl)phenol, characterized in that: The invention comprises a process of using Bronsted acidic ionic liquid as a catalyst and propylene glycol fatty acid ester as an auxiliary agent to react 3-(2-hydroxy-2-propyl)phenol and hydrogen peroxide to generate resorcinol.

2. The method for synthesizing resorcinol from 3-(2-hydroxy-2-propyl)phenol according to claim 1, characterized in that: The Bronsted acidic ionic liquid is a sulfonic acid type ionic liquid, preferably [TEBSA][HSO4]; Preferably, the added amount of the Bronsted acidic ionic liquid is 0.5-2% of the mass of 3-(2-hydroxy-2-propyl)phenol.

3. The method for synthesizing resorcinol from 3-(2-hydroxy-2-propyl)phenol according to claim 1, characterized in that: The propylene glycol fatty acid ester is at least one of the substances having the following structural expressions: Wherein, n is 8-16; Preferably, the amount of the propylene glycol fatty acid ester is 1-5% of the mass of the catalyst.

4. The method for synthesizing resorcinol from 3-(2-hydroxy-2-propyl)phenol according to any one of claims 1 to 3, characterized in that: The molar ratio of 3-(2-hydroxy-2-propyl)phenol to hydrogen peroxide is 1:(1-10), preferably 1:(2-5); Preferably, the mass concentration of the hydrogen peroxide is 2-30%, preferably 3-10%.

5. The method for synthesizing resorcinol from 3-(2-hydroxy-2-propyl)phenol according to any one of claims 1 to 4, characterized in that: The reaction temperature is 20-70°C, and the reaction time is 3-20 minutes.

6. The method for synthesizing resorcinol from 3-(2-hydroxy-2-propyl)phenol according to any one of claims 1 to 5, characterized in that: The reaction adding process is: firstly, 3-(2-hydroxy-2-propyl)phenol and the co-catalyst are mixed in an organic solvent to obtain an organic phase, the catalyst and hydrogen peroxide are mixed to obtain an aqueous phase, and then the aqueous phase is added to the organic phase for reaction.

7. The method for synthesizing resorcinol from 3-(2-hydroxy-2-propyl)phenol according to claim 6, characterized in that: The organic solvent is a ketone, preferably one or more of acetone, methyl ethyl ketone, and methyl isobutyl ketone.

8. The method for synthesizing resorcinol from 3-(2-hydroxy-2-propyl)phenol according to claim 6 or 7, characterized in that: The amount of the organic solvent used is 4-25 times the mass of 3-(2-hydroxy-2-propyl)phenol.

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