Method for co-producing xanthene and ethyl phenol

Abstract

The invention provides a method for co-producing xanthene and ethyl phenol, and belongs to the technical field of organic chemical industry. According to the method, phenol and calcium carbide are used as raw materials, calcium phenolate is used as a catalyst, and xanthene and ethyl phenol are synthesized through a heating reaction in an inert atmosphere and a closed reactor. The calcium carbide used in the method is wide in source and low in price, has the advantages of no need of additional catalysts and solvents, short route, high product yield and the like, and overcomes the problems in the prior art. In addition, the method co-produces xanthene and ethyl phenol, and the economical efficiency of a traditional phenol alkylation process is remarkably improved.

Description

Technical Field

[0001] The invention relates to the technical field of organic chemical industry, and in particular to a method for co-producing xanthene and ethylphenol. Background Art

[0002] As a type of short-chain alkylphenol, ethylphenol can be used to produce important chemicals such as phenolic resin, rubber antioxidant, surfactant, and low-residue pesticide. At present, the methods for producing ethylphenol include crude oil separation, ethylbenzene hydrolysis, and phenol alkylation. Among them, the phenol alkylation method is the most common method, which generates products by alkylation reaction between phenol and olefins / alcohols under the action of acidic catalysts. However, olefins are prone to oligomerization and alcohols are prone to dehydration reactions on acidic catalysts, resulting in low product selectivity. A Chinese patent (CN201010123979.3) reports a method for synthesizing 4-ethylphenol by reaction in a mixed solution of ethanol and water using diethyl carbonate and phenol as raw materials and modified microporous molecular sieves as catalysts. The product selectivity is improved, but the reaction system is complex and the source of the raw material diethyl carbonate is not extensive. Chinese patents (CN201410558325.1) (CN202010199444.8) respectively reported methods for preparing 4-ethylphenol by catalytic pyrolysis of biomass and microbial fermentation, and the product yield was low, about 10%.

[0003] Xanthene compounds are mainly found in herbs, fungi and microorganisms. Different substituents on the benzene ring give them different chemical and biological properties. They have important applications in the fields of medicine, fluorescent materials, dyes, etc. Except for a few that can be extracted and separated from natural plants such as mangosteen and mangosteen peel, most of the xanthene compounds are condensed with 2-naphthol and aldehyde, using proton acid or Lewis acid catalysts. Chinese patents (CN201310103521.5) and (CN201410351149.4) respectively disclose methods for synthesizing xanthene compounds by condensing aromatic aldehydes with 2-naphthol catalyzed by strongly acidic ion exchange resins and Bronsted acidic ionic liquids. This method faces a series of production and environmental problems such as catalyst preparation and recovery, easy generation of large amounts of wastewater, and equipment corrosion.

[0004] In summary, ethylphenol and xanthene are synthesized using different methods, both of which require strong acid catalysts. Some processes have complex reaction systems and limited sources of raw materials, and some processes have problems with wastewater and equipment corrosion. Summary of the invention

[0005] The present invention provides a method for co-producing xanthene and ethylphenol by one-pot reaction of phenol and calcium carbide. The calcium carbide used in the method is widely available and inexpensive, has the advantages of no need for an external catalyst and solvent, short route, high product yield, etc., and overcomes the problems existing in the prior art. In addition, the method co-produces xanthene and ethylphenol, significantly improving the economic efficiency of the traditional phenol alkylation process.

[0006] The technical solution of the present invention is as follows:

[0007] A method for co-producing xanthene and ethylphenol, using phenol and calcium carbide as raw materials, calcium phenolate as a catalyst, heating reaction in an inert atmosphere and a closed reactor to synthesize xanthene and ethylphenol.

[0008] Furthermore, the calcium phenate, i.e. the catalyst required for the alkylation reaction, is generated during the reaction of phenol and calcium carbide.

[0009] Preferably, the inert atmosphere may be nitrogen or argon. Preferably, the phenol is anhydrous phenol.

[0010] Furthermore, the temperature of the heating reaction is 250-400°C; preferably, the temperature of the heating reaction is 325-375°C.

[0011] Furthermore, the heating reaction time is 0.5-6h. The length of the reaction time is related to the reaction temperature. The longer the reaction time is below 350°C, the higher the yield of xanthene and ethylphenol. However, the optimal reaction time needs to be determined by comprehensively considering the production efficiency (yield per unit time) and the total yield. Above 350°C, the yield of xanthene and ethylphenol decreases with the increase of reaction time.

[0012] Further, the molar ratio of calcium carbide to phenol is 1:(1-16); preferably, the molar ratio of calcium carbide to phenol is 1:(8-16). Generally, the more phenol is added, the more favorable the alkylation reaction and hydrogenation reaction are, and the higher the total yield of xanthene and ethylphenol is.

[0013] Furthermore, the pressure of the heating reaction comes from the pressure generated by the heating of the raw materials themselves, and no additional pressurization is required.

[0014] Furthermore, the calcium carbide is ground to 50-120 meshes before being added to the closed reactor. Generally, the larger the mesh size of the calcium carbide (i.e., the finer the calcium carbide), the higher the total yield of xanthene and ethylphenol. Preferably, the mesh size of the calcium carbide is 80-100 meshes.

[0015] Furthermore, the products of the heating reaction include xanthene, 2-ethylphenol and 4-ethylphenol.

[0016] Furthermore, the product of the heating reaction is cooled, and then the gas, solid and liquid phases are separated to obtain the product xanthene and ethylphenol from the liquid phase component.

[0017] The mechanism of the reaction of calcium carbide and phenol is shown as follows:

[0018]

[0019] In the reaction process, calcium carbide is mainly used for the alkylation of phenol and phenol dehydration products. First, phenol undergoes alkylation with acetylene derived from calcium carbide to form vinyl phenol or undergoes intermolecular dehydration to form diphenyl ether. Subsequently, vinyl phenol and phenol undergo dehydration and cyclization to form xanthene, or diphenyl ether is alkylated by acetylene derived from calcium carbide and then cyclized to form xanthene. Ethyl phenol is produced by hydrogenation of vinyl phenol and phenol. Calcium phenoxide, a derivative of calcium carbide, has a catalytic effect on the reaction process.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] (1) Calcium carbide raw materials are bulk platform compounds with wide sources and low prices;

[0022] (2) The present invention uses the reaction product calcium phenolate as a catalyst, does not require an external catalyst and solvent, the reaction system is simple, and the reaction conditions are relatively mild;

[0023] (3) The one-pot process of the present invention co-produces xanthene and ethylphenol, which has a short process flow and high economic efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope of the present invention.

[0025] Figure 1 is the total ion chromatogram of the liquid product in Example 1;

[0026] Figure 2 is the mass spectrum of the product 2-ethylphenol in Example 1;

[0027] Figure 3 is the mass spectrum of the product 4-ethylphenol in Example 1;

[0028] Figure 4 This is the mass spectrum of the product xanthene in Example 1. DETAILED DESCRIPTION

[0029] As used herein:

[0030] "Prepared from" is synonymous with "comprising." As used herein, the terms "comprising," "including," "having," "containing," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises the listed elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

[0031] When an amount, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper preferred values ​​and lower preferred values, this should be understood as specifically disclosing all ranges formed by any pairing of any range upper limit or preferred value with any range lower limit or preferred value, regardless of whether the range is disclosed separately. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted as including ranges "1 to 4", "1 to 3", "1 to 2", "1 to 2 and 4 to 5", "1 to 3 and 5", etc. When a numerical range is described in this article, unless otherwise stated, the range is intended to include its end values ​​and all integers and fractions within the range.

[0032] "And / or" is used to indicate that one or both of the stated situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0033] The technical scheme of the present invention will be described in detail below in conjunction with specific embodiments, but those skilled in the art will appreciate that the following examples are only used to illustrate the present invention and should not be considered to limit the scope of the present invention. If specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0034] In the present invention, there is no particular limitation on the type of reactor, and a closed reactor well known to those skilled in the art can be used. In the following examples, an ice-water bath is used to cool the reactor, but the cooling method is not limited to an ice-water bath, and any medium and equipment that can be cooled can be used.

[0035] In the following examples, tetrahydrofuran (THF) was used to soak the solid-liquid mixed product, and then the liquid product was separated by filtration. The separation of the solid-liquid product is not limited to the described method, and any solid-liquid separation method known to those skilled in the art can be used.

[0036] In the present invention, the qualitative analysis of the liquid product is performed by GC-MS; the quantitative analysis of 2-ethylphenol, 4-ethylphenol and xanthene is performed by GC analysis, and the yield of each product is the percentage of the molar amount of each product to the molar amount of the added calcium carbide.

[0037] Example 1

[0038] A method for co-producing xanthene and ethylphenol: grind calcium carbide to 80-100 meshes, add calcium carbide and anhydrous phenol into a closed reactor at a molar ratio of 1:8, introduce nitrogen to purge and exhaust the air in the reactor, seal the reactor, heat to 350°C, and react for 6 hours. After the reaction is completed, cool the reactor to room temperature with an ice water bath, collect gaseous products, and then soak the solid-liquid mixed product in tetrahydrofuran (THF) for 12 hours, and filter to obtain a liquid product.

[0039] GC results in GC-MS are as follows Figure 1 shown. Figure 1 The MS results of the peak at retention time 27.8 min are as follows Figure 2 , which is consistent with the mass spectrum of 2-ethylphenol in the NIST library; the MS result of the peak at retention time 29.3min is as follows Figure 3 , which is consistent with the mass spectrum of 4-ethylphenol in the NIST library; the MS result of the peak at retention time 51.7min is as follows Figure 4 As shown, it is consistent with the mass spectrum of xanthene in the NIST library.

[0040] GC quantitative analysis showed that the yields of 2-ethylphenol, 4-ethylphenol and xanthene were 12.4%, 7.3% and 24.2%, respectively, and the total yield of the product was 43.9%.

[0041] Example 2

[0042] The difference from Example 1 is that the reaction time is 0.5 h. The yields of 2-ethylphenol, 4-ethylphenol and xanthene measured by GC are 6.5%, 12.6% and 7.1% respectively. The total yield of the product is 26.2%.

[0043] Example 3

[0044] The difference from Example 1 is that the reaction time is 2 hours. The yields of 2-ethylphenol, 4-ethylphenol and xanthene measured by GC are 14.5%, 11.7% and 17.6% respectively. The total yield of the product is 43.8%.

[0045] Example 4

[0046] The difference from Example 1 is that the reaction temperature is 250°C and the reaction time is 2 hours. The yields of 2-ethylphenol, 4-ethylphenol and xanthene measured by GC are 1.5%, 4.2% and 0.8% respectively. The total yield of the product is 6.5%.

[0047] Example 5

[0048] The difference from Example 4 is that the reaction temperature is 275° C. The yields of 2-ethylphenol, 4-ethylphenol and xanthene measured by GC are 4.8%, 9.7% and 2.1% respectively. The total yield of the product is 16.6%.

[0049] Example 6

[0050] The difference from Example 4 is that the reaction temperature is 300° C. The yields of 2-ethylphenol, 4-ethylphenol and xanthene measured by GC are 6.5%, 12.5% ​​and 6.4% respectively. The total yield of the product is 25.4%.

[0051] Example 7

[0052] The difference from Example 6 is that the reaction time is 6 hours. The yields of 2-ethylphenol, 4-ethylphenol and xanthene measured by GC are 13.1%, 13.9% and 15.1% respectively. The total yield of the product is 42.1%.

[0053] Example 8

[0054] The difference from Example 4 is that the reaction temperature is 325° C. The yields of 2-ethylphenol, 4-ethylphenol and xanthene measured by GC are 13.2%, 13.6% and 15.9% respectively. The total yield of the product is 42.7%.

[0055] Example 9

[0056] The difference from Example 4 is that the reaction temperature is 375° C. The yields of 2-ethylphenol, 4-ethylphenol and xanthene measured by GC are 14.2%, 9.2% and 17.1% respectively. The total yield of the product is 40.5%.

[0057] Example 10

[0058] The difference from Example 4 is that the reaction temperature is 400° C. The yields of 2-ethylphenol, 4-ethylphenol and xanthene measured by GC are 12.7%, 7.4% and 16.6% respectively. The total yield of the product is 36.7%.

[0059] Embodiment 11

[0060] The difference from Example 10 is that the reaction time is 6 hours. The yields of 2-ethylphenol, 4-ethylphenol and xanthene measured by GC are 10.5%, 5.5% and 14.8% respectively. The total yield of the product is 30.8%.

[0061] Example 12

[0062] The difference from Example 3 is that the molar ratio of calcium carbide to phenol is 1:1. The yields of 2-ethylphenol, 4-ethylphenol and xanthene measured by GC are 0.7%, 1.1% and 0.1% respectively. The total yield of the product is 1.9%.

[0063] Example 13

[0064] The difference from Example 3 is that the molar ratio of calcium carbide to phenol is 1:4. The yields of 2-ethylphenol, 4-ethylphenol and xanthene measured by GC are 5.6%, 9.2% and 8.3% respectively. The total yield of the product is 23.1%.

[0065] Embodiment 14

[0066] The difference from Example 3 is that the molar ratio of calcium carbide to phenol is 1:16. The yields of 2-ethylphenol, 4-ethylphenol and xanthene measured by GC are 17.6%, 16.7% and 21.2% respectively. The total yield of the product is 55.5%.

[0067] Embodiment 15

[0068] The difference from Example 14 is that the reaction time is 6 hours. The yields of 2-ethylphenol, 4-ethylphenol and xanthene measured by GC are 21.2%, 17.1% and 26.0% respectively. The total yield of the product is 64.3%.

[0069] Example 16

[0070] The difference from Example 3 is that the calcium carbide is ground to 20-40 mesh. The yields of 2-ethylphenol, 4-ethylphenol and xanthene measured by GC are 8.9%, 7.3% and 10.4% respectively. The total yield of the product is 26.6%.

[0071] Embodiment 17

[0072] The difference from Example 3 is that the calcium carbide is ground to 40-60 mesh. The yields of 2-ethylphenol, 4-ethylphenol and xanthene measured by GC are 10.6%, 9.7% and 14.2% respectively. The total yield of the product is 34.5%.

[0073] The reaction materials, conditions and results of Examples 1-17 are shown in Table 1.

[0074] Table 1 Reaction materials, conditions and results of Examples 1-17 of the present invention

[0075]

[0076] As can be seen from Table 1, the more phenol is used and the larger the mesh size of calcium carbide grinding, the higher the yield of xanthene and 2- / 4-ethylphenol. The reaction temperature and time have different effects on the yield of a single product. The yield of xanthene increases first and then decreases with the increase of reaction temperature, reaches the maximum at 350°C, and gradually increases with the increase of reaction time. Since high temperature will cause the side chain of 2- / 4-ethylphenol to break, the formation of ethylphenol is most favorable at a relatively low temperature and a long time (300°C, 6h).

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

[0078] In addition, those skilled in the art will appreciate that, although some embodiments herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present invention and to form different embodiments. For example, in the above claims, any one of the claimed embodiments may be used in any combination. The information disclosed in this background technology section is intended only to deepen the understanding of the overall background technology of the present invention and should not be regarded as an admission or in any form of implication that the information constitutes prior art known to those skilled in the art.

Claims

1. A method for co-producing xanthene and ethylphenol, characterized in that: Phenol and calcium carbide are used as raw materials, calcium phenolate is used as a catalyst, and xanthene and ethylphenol are synthesized by heating reaction in an inert atmosphere and a closed reactor.

2. The method for co-producing xanthene and ethylphenol according to claim 1, characterized in that: The calcium phenate is produced during the reaction of phenol and calcium carbide.

3. The method for co-producing xanthene and ethylphenol according to claim 1, characterized in that: The temperature of the heating reaction is 250-400°C; Preferably, the temperature of the heating reaction is 325-375°C.

4. The method for co-producing xanthene and ethylphenol according to claim 1, characterized in that: The heating reaction time is 0.5-6h.

5. The method for co-producing xanthene and ethylphenol according to claim 1, characterized in that: The molar ratio of calcium carbide to phenol is 1:(1-16); Preferably, the molar ratio of calcium carbide to phenol is 1:(8-16).

6. The method for co-producing xanthene and ethylphenol according to claim 1, characterized in that: The pressure of the heating reaction comes from the pressure generated by the heating of the raw materials themselves, and no additional pressurization is required.

7. The method for co-producing xanthene and ethylphenol according to claim 1, characterized in that: The calcium carbide is ground to 50-120 mesh before being added into the closed reactor; Preferably, the calcium carbide is ground to a mesh size of 80-100 meshes.

8. The method for co-producing xanthene and ethylphenol according to claim 1, characterized in that: The products of the heating reaction include xanthene, 2-ethylphenol and 4-ethylphenol.

9. The method for co-producing xanthene and ethylphenol according to claim 1, characterized in that: The product of the heating reaction is cooled, and then separated into gas, solid and liquid phases, and the products xanthene and ethylphenol are obtained from the liquid phase component.

10. The method for co-producing xanthene and ethylphenol according to claim 1, characterized in that: The inert atmosphere includes nitrogen or argon; And / or, the phenol is anhydrous phenol.

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