Method for preparing aromatic nitrile from alkyl substituted phenolic compound
By reacting alkyl-substituted phenolic compounds with phosphorus trihalides to generate halogenated aromatic hydrocarbons and using phosphorous acid as a catalyst, combined with nickel salts, zinc salts, and cyanides for hydrocyanation, the low yield and environmentally unfriendly problems of existing aromatic nitrile production methods are solved, realizing efficient and green aromatic nitrile synthesis, reducing costs and promoting resource recycling.
Patent Information
- Application Number
- CN202511516768.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-23
- Publication Date
- 2026-01-23
AI Technical Summary
Existing methods for producing aromatic nitriles suffer from drawbacks such as low yield, complex processes, high costs, and environmental unfriendliness, making it difficult to achieve efficient, green, and economical synthesis.
Using alkyl-substituted phenolic compounds as raw materials, haloaromatics and phosphorous acid are generated by reacting with phosphorus trihalides. These haloaromatics and phosphorous acid are then used as Brønsted acid co-catalysts to carry out hydrocyanation reactions with nickel salts, zinc salts, and cyanides, achieving efficient synthesis of aromatic nitrile. This method utilizes phenolic substances in industrial waste liquid as raw materials, simplifying the process and reducing by-product treatment.
It has increased the yield of aromatic nitrile, reduced production costs, realized the transformation from pollution control to resource recycling, provided a technical path for green transformation, simplified the process flow, and improved atom economy.
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Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of compound synthesis, and particularly relates to a method for preparing aromatic nitrile from alkyl-substituted phenolic compound. BACKGROUND
[0002] Aromatic nitrile compounds are important intermediates and fine chemicals in organic synthesis, which are characterized by the direct connection of a cyano group (-CN) on an aromatic ring. This functional group has extremely high chemical reactivity and can be converted into various important functional groups such as carboxylic acid (-COOH), amide (-CONH2), amine group (-CH2NH2), and heterocyclic structure. Therefore, aromatic nitriles play an indispensable role in the fields of medicine, pesticides, polymer materials, dyes, and functional materials. Developing efficient, green, and economical methods for synthesizing aromatic nitriles is of great significance for promoting the development of related industries.
[0003] In the field of synthesis of aromatic nitrile compounds, existing technologies have developed various methods, including liquid-phase ammoxidation, Sandmeyer method, and nitro-substituted cyanation. Taking the synthesis of m-tolunitrile as an example, liquid-phase ammoxidation uses m-xylene as the raw material to react with ammonia and air in liquid phase under the action of a catalyst to synthesize m-tolunitrile in one step. In the specific operation, silica gel-supported cobalt-manganese-nickel composite oxides are commonly used as catalysts to prepare m-tolunitrile under relatively low temperature and pressure conditions. Although liquid-phase ammoxidation has the potential for high selectivity in theory, meaning it can mainly generate the target product and reduce the generation of by-products, in actual application, its reaction yield is generally low, and the activity of the catalyst still needs to be further optimized. These factors together limit the overall efficiency of liquid-phase ammoxidation, restricting its application in actual industrial production.
[0004] Sandmeyer method is a method for synthesizing m-tolunitrile through diazo functional group substitution reaction. In this reaction, the diazo functional group is replaced by halogen or cyano under the catalysis of cuprous salt. One of the significant advantages of Sandmeyer method is that it can ensure the formation of only one isomer, thereby improving the purity of the product. As a traditional process for preparing m-tolunitrile, Sandmeyer method converts m-methylaniline into m-tolunitrile through diazotization reaction. However, this process also has obvious disadvantages. On the one hand, the process is relatively complex, requiring multiple steps and strict condition control; on the other hand, the reaction uses highly toxic cyanide, which not only poses a threat to the safety of operators, but also significantly increases the cost of three-waste treatment. Therefore, with the improvement of environmental awareness and the progress of process technology, Sandmeyer method has gradually been eliminated.
[0005] The nitro-substituted cyanation method synthesizes m-tolunitrile by substituting a nitro group with a cyano group using nitrotoluene as a raw material. Although the nitro-substituted cyanation method has certain feasibility in principle, the raw material nitrotoluene is relatively difficult to obtain, and large-scale promotion has not been achieved at present. This may be due to the reasons such as high cost of raw materials, harsh reaction conditions, or unsatisfactory product yield.
[0006] In summary, the existing aromatic nitrile production methods have the defects of low yield, complex process, high cost, and environmental unfriendliness. Therefore, developing a new method for preparing aromatic nitriles to improve the yield, simplify the process, reduce the production cost, and reduce the "three wastes" emissions has become an important demand in the field of chemical industry. SUMMARY
[0007] In view of the deficiencies in the prior art, the present application discloses a method for preparing aromatic nitriles from alkyl-substituted phenolic compounds, which uses alkyl-substituted phenolic compounds as raw materials. This method not only achieves efficient synthesis of aromatic nitriles through the synergy between each step, but also converts phenolic compounds in industrial waste liquid into high-value chemicals, providing a new technical path for the treatment and resource utilization of phenolic-containing waste liquid.
[0008] To achieve the above technical purposes, the present application provides a method for preparing aromatic nitriles from alkyl-substituted phenolic compounds, comprising the following steps: (1) Dissolve the alkyl-substituted phenolic compound in a nitrile solvent, add phosphorus trihalide and stir to obtain a first solution; (2) Dissolve the nickel salt and zinc salt in a nitrile solvent, stir, add cyanide, and then dehydrate to obtain a second dehydrated solution; (3) Under the condition of passing ammonia, add the second dehydrated solution and a reaction aid to the first solution to perform a hydrocyanation reaction to prepare an aromatic nitrile compound.
[0009] The core points of the method for preparing aromatic nitriles from alkyl-substituted phenolic compounds of the present application are at least reflected in the selection of raw materials and process design.
[0010] Regarding raw material selection, conventional methods for preparing aromatic nitriles in existing technologies generally use pre-functionalized aromatic hydrocarbons (such as halogenated aromatics, aromatic amines, or nitroaromatics) as raw materials. The preparation of these raw materials often requires multiple synthetic steps, increasing overall production costs and process complexity. This invention, however, uses alkyl-substituted phenolic compounds as raw materials. These raw materials are not only readily available but can also be derived from alkyl-substituted phenolic compounds found in phenol-containing wastewater from related industries. This type of phenol-containing wastewater typically originates from coal chemical and petroleum refining processes, making it widely available and extremely low-cost. This method transforms industrial waste that previously required paid treatment into high-value raw materials for synthesizing aromatic nitriles, significantly reducing production costs and achieving a shift from pollution control to resource recycling, providing a practical and feasible technological path for the green transformation of related industries.
[0011] In terms of process design, this invention achieves high efficiency and environmental friendliness through unique synergistic reaction steps. The key to this invention's method lies in the following: First, alkyl-substituted phenolic compounds react with phosphorus trihalides to generate haloaromatics and the byproduct phosphorous acid in situ. However, the phosphorous acid (H3PO3) generated in this step is not treated as waste, but is utilized as a co-catalyst for the in-situ generation of Brønsted acid (B acid) in the hydrocyanation reaction. This internal recycling design, where a byproduct from one step becomes a reaction promoter in another, significantly improves the efficiency and atom economy of the second-step cyanation reaction. At the same time, it eliminates the need for byproduct separation and the addition of exogenous reagents, making the entire process simpler and more environmentally friendly.
[0012] In summary, the method of this invention provides a novel route for the synthesis of aromatic nitriles that combines significant economic benefits, environmental friendliness, and technological advancement through the selection of raw materials and the synergy of processes during the reaction, demonstrating broad prospects for industrialization.
[0013] In a further example of the present invention, the alkyl-substituted phenolic compound described in step (1) has the general formula R. 1~5 -Ar-OH; where R 1~5 It is one or more of five sites on the benzene ring that can be substituted, and the substituent at each site is independently selected from hydrogen atoms or straight-chain or branched alkyl groups, having a carbon number of C1 to C20, preferably monosubstituted or disubstituted alkylphenols, and the substituent at each site is independently selected from straight-chain or branched alkyl groups having a carbon number of C1 to C5, further preferably any one of methylphenol, ethylphenol, and dimethylphenol; And / or, the general structural formula of the phosphorus trihalide mentioned in step (1) is PX3, where X is any one of Cl, Br, and I.
[0014] In further examples of the present application, the nitrile solvents in step (1) and step (2) are the same, and the nitrile solvents are high-boiling nitrile solvents with a boiling point higher than 200℃, preferably one or more of ethyl succinonitrile, methyl glutaronitrile, 2,3-dimethyl succinonitrile or adiponitrile.
[0015] Since the hydrocyanation reaction in step (3) needs to be carried out at a higher temperature, a high-boiling nitrile solvent is selected to maintain the stability of the reaction.
[0016] In further examples of the present application, the nickel salt in step (2) includes one or more of NiCl2, NiI2, NiBr2; and / or, the zinc salt in step (2) includes one or more of ZnCl2, ZnBr2, ZnI2; and / or, the cyanide in step (2) includes one or more of KCN, NaCN, Zn(CN)2, K4[Fe(CN)6], Ni(CN)2.
[0017] In further examples of the present application, the reaction aid in step (3) is one or more of trimethyl phosphite, triethyl phosphite, tritolyl phosphite, tris(2,4-dimethyl)phenyl phosphite, tris(3,5-dimethyl)phenyl phosphite, (dimethylphenyl)phosphite, (monomethylphenyl)phosphite, etc., preferably one or more of trimethyl phosphite, tritolyl phosphite, triethyl phosphite or (dimethylphenyl)phosphite.
[0018] In further examples of the present application, the molar ratio of the alkyl-substituted phenolic compound in step (1) to the phosphorus trihalide in step (1) is 1:(0.5-2.25); and / or, the molar ratio of the alkyl-substituted phenolic compound in step (1) to the nickel salt in step (2) is (1-10):1; and / or, the molar ratio of the alkyl-substituted phenolic compound in step (1) to the zinc salt in step (2) is (1-30):1; and / or, the molar ratio of the alkyl-substituted phenolic compound in step (1) to the cyanide in step (2) is (1-1.75):1.
[0019] In further examples of the present application, the molar ratio of the alkyl-substituted phenolic compound in step (1) to the amount of the nitrile solvent added in step (1) and step (2) is 1:(5-60); and / or, the molar ratio of the alkyl-substituted phenolic compound in step (1) to the amount of the reaction aid added in step (3) is (1-50):1.
[0020] In a further example of the present application, the temperature of the stirring in step (1) is room temperature, and the stirring time is 1-72 h.
[0021] In a further example of the present application, the temperature of the stirring and the secondary stirring in step (2) is the same, and the temperature is 15-105℃, and the stirring time is 1-10 h; and / or, the stirring time in step (2) is 1-10 h; and / or, the secondary stirring time in step (2) is 1-6 h; and / or, the temperature of the dehydration in step (2) is 20-105℃, and the dehydration pressure is 1-10 kPa.
[0022] In a further example of the present application, the temperature of the hydrocyanation reaction in step (3) is 60-255℃, and the time is 1-72 h; and / or, the ammonia flow rate in step (3) is 5-50 sccm.
[0023] Compared with the prior art, the present application has the following advantages:
[0024] (1) The method for preparing aromatic nitrile from alkyl-substituted phenolic compounds according to the present application realizes high efficiency and greenization through unique reaction steps. The by-product phosphorous acid generated from the reaction of alkyl-substituted phenolic compounds and phosphorus trihalide is used as an in-situ generated Bronsted acid co-catalyst in the hydrocyanation reaction, and the internal circulation design improves the cyanation reaction efficiency and atom economy, thereby saving the separation of by-products and the addition of external reagents, and making the process flow more concise and environmentally friendly.
[0025] (2) The method for preparing aromatic nitrile from alkyl-substituted phenolic compounds according to the present application abandons the pre-functionalized aromatic hydrocarbon raw material in the prior art which needs to be synthesized in multiple steps, and selects the easily available alkyl-substituted phenolic compounds, and can utilize the same industry phenolic waste liquid (widely available and extremely low cost), thereby converting the industrial waste which needs to be paid for treatment into high-value raw materials, greatly reducing the production cost, realizing the transformation from pollution treatment to resource recycling, and providing a feasible path for the green transformation of the industry. DETAILED DESCRIPTION
[0026] In order to facilitate the understanding of the present application, the present application will be described more fully below, and the preferred embodiments of the present application are given. However, it should be understood that these embodiments are only used for more detailed description, and should not be understood as limiting the present application in any form, i.e. not intended to limit the protection scope of the present application.
[0027] Unless otherwise defined, the technical terms used in the following examples have the same meanings as commonly understood by one of ordinary skill in the art to which this invention belongs. The test reagents used in the following examples are all conventional biochemical reagents unless otherwise specified; the experimental methods used are all conventional methods unless otherwise specified.
[0028] Example 1
[0029] A method for preparing aromatic nitrile from an alkyl-substituted phenolic compound, comprising the following steps: (1) 10.81 g of m-cresol was dissolved in 69.05 g of 2,3-dimethylsuccinonitrile, 7.12 g of PCl3 was slowly added dropwise, and the first solution was obtained by stirring at room temperature for 24 h; (2) 5.26 g of NiI2 and 1.82 g of ZnI2 were dissolved in 69.05 g of 2,3-dimethylsuccinonitrile, 4.53 g of KCN was added as a cyanide source after stirring at 63 °C for 3 h, and the second dehydration solution was obtained by stirring for another 3 h until uniform, and then water was removed at 105 °C under the condition of 10 kPa; (3) The second dehydration solution, 7.56 g of reaction aid trimethyl phosphite, was added to the first solution under the condition of continuously introducing dry ammonia at a rate of 35 SCCM, and m-cresyl cyanide was obtained by performing hydrocyanation reaction at 120 °C under the condition of normal pressure reflux for 18 h.
[0030] Example 2
[0031] A method for preparing aromatic nitrile from an alkyl-substituted phenolic compound, comprising the following steps: (1) 20.63 g of 2,4-di-tert-butylphenol was dissolved in 88.66 g of methylglutaronitrile, 13.56 g of PCl3 was slowly added dropwise, and the first solution was obtained by stirring at room temperature for 10 h; (2) 2.89 g of NiCl2 and 0.75 g of ZnCl2 were dissolved in 88.66 g of methylglutaronitrile, 7.61 g of Zn(CN)2 was added as a cyanide source after stirring at 85 °C for 1.5 h, and the second dehydration solution was obtained by stirring for another 1 h until uniform, and then water was removed at 66 °C under the condition of 5.1 kPa; (3) The second dehydration solution, 4.35 g of reaction aid trimethylphenyl phosphite, was added to the first solution under the condition of continuously introducing dry ammonia at a rate of 20 SCCM, and 2,4-di-tert-butylphenyl cyanide was obtained by performing hydrocyanation reaction at 165 °C under the condition of normal pressure reflux for 31 h.
[0032] Example 3
[0033] A method for preparing aromatic nitrile from an alkyl-substituted phenolic compound, comprising the following steps: (1) 10.81 g of p-methylphenol was dissolved in 276.53 g of ethylsuccinonitrile, 26.79 g of PCl3 was added dropwise slowly, and the first solution was obtained by stirring at room temperature for 33 h; (2) 12.75 g of NiBr2 and 0.99 g of ZnCl2 were dissolved in 276.53 g of ethylsuccinonitrile, and after stirring at 40°C for 5.5 h, 30.55 g of K4[Fe(CN)6] was added as a cyanide source, and the second dehydration solution was obtained by stirring for 4.5 h until uniform, and then water was removed at 45°C and 2.3 kPa; (3) The second dehydration solution and 13.55 g of reaction aid triethyl phosphite were added to the first solution under the condition of continuously introducing dry ammonia at a rate of 17 SCCM, and the p-methylphenyl cyanide was obtained by hydrocyanation reaction at 147°C under atmospheric reflux for 44 h.
[0034] Example 4
[0035] A method for preparing aromatic nitrile from an alkyl-substituted phenolic compound, comprising the following steps: (1) 16.42 g of 2-tert-butyl-4-methylphenol was dissolved in 165.52 g of hexanediol nitrile, 19.58 g of PCl3 was added dropwise slowly, and the first solution was obtained by stirring at room temperature for 52 h; (2) 15.77 g of NiI2 and 2.04 g of ZnBr2 were dissolved in 165.62 g of hexanediol nitrile, and after stirring at 22°C for 8.5 h, 3.03 g of NaCN was added as a cyanide source, and the second dehydration solution was obtained by stirring for 3.5 h until uniform, and then water was removed at 80°C and 8.1 kPa; (3) The second dehydration solution and 8.68 g of reaction aid dimethylphenyl phosphite were added to the first solution under the condition of continuously introducing dry ammonia at a rate of 50 SCCM, and the p-methylphenyl cyanide was obtained by hydrocyanation reaction at 193°C under atmospheric reflux for 68 h.
[0036] Comparative Example 1
[0037] Based on the method for preparing aromatic nitrile from an alkyl-substituted phenolic compound in Example 1, the present comparative example does not perform dehydration in step (2) compared with Example 1, comprising the following steps: (1) 10.81 g of p-methylphenol was dissolved in 276.53 g of ethylsuccinonitrile, 26.79 g of PCl3 was added dropwise slowly, and the first solution was obtained by stirring at room temperature for 33 h; (2) 12.75 g of NiBr2 and 0.99 g of ZnCl2 were dissolved in 276.53 g of ethylsuccinonitrile, and after stirring at 40°C for 5.5 h, 30.55 g of K4[Fe(CN)6] was added as a cyanide source, and the second dehydration solution was obtained by stirring for 4.5 h until uniform, and then water was removed at 45°C and 2.3 kPa; (3) The second solution, 7.56 g of reaction aid trimethyl phosphite, was added to the first solution under the condition of continuously passing dry ammonia gas at a rate of 35 SCCM, and a hydrocyanation reaction was carried out at 120 °C under normal pressure reflux for 18 h to obtain m-tolunitrile.
[0038] Comparative Example 2
[0039] Based on the method for preparing an aromatic nitrile from an alkyl-substituted phenolic compound of Example 1, this comparative example differs from Example 1 in that the hydrocyanation reaction in step (3) was carried out under normal pressure air atmosphere, and included the following steps: (1) 10.81 g of m-methylphenol was dissolved in 69.05 g of 2,3-dimethylbutanedinitrile, and 7.12 g of PCl3 was slowly added dropwise, and the mixture was stirred at room temperature for 24 h to obtain a first solution; (2) 5.26 g of NiI2 and 1.82 g of ZnI2 were dissolved in 69.05 g of 2,3-dimethylbutanedinitrile, and the mixture was stirred at 63 °C for 3 h, and then 4.53 g of KCN was added as a cyanide source and stirred for another 3 h until uniform, and then water was removed at 105 °C under a pressure of 10 kPa to obtain a second dehydrated solution; (3) The second dehydrated solution, 7.56 g of reaction aid trimethyl phosphite, was added to the first solution under the condition of continuously passing dry ammonia gas at a rate of 35 SCCM, and a hydrocyanation reaction was carried out at 120 °C under normal pressure reflux for 18 h to obtain m-tolunitrile.
[0040] Comparative Example 3
[0041] Based on the method for preparing an aromatic nitrile from an alkyl-substituted phenolic compound of Example 1, this comparative example differs from Example 1 in that no ZnI2 was added in step (2). It included the following steps: (1) 10.81 g of m-methylphenol was dissolved in 69.05 g of 2,3-dimethylbutanedinitrile, and 7.12 g of PCl3 was slowly added dropwise, and the mixture was stirred at room temperature for 24 h to obtain a first solution; (2) 5.26 g of NiI2 was dissolved in 69.05 g of 2,3-dimethylbutanedinitrile, and the mixture was stirred at 63 °C for 3 h, and then 4.53 g of KCN was added as a cyanide source and stirred for another 3 h until uniform, and then water was removed at 105 °C under a pressure of 10 kPa to obtain a second dehydrated solution; (3) The second dehydrated solution, 7.56 g of reaction aid trimethyl phosphite, was added to the first solution under the condition of continuously passing dry ammonia gas at a rate of 35 SCCM, and a hydrocyanation reaction was carried out at 120 °C under normal pressure reflux for 18 h to obtain m-tolunitrile.
[0042] Comparative Example 4
[0043] A method for preparing aromatic nitrile based on the alkyl-substituted phenolic compound of Example 1, compared with Example 1, no reaction aid trimethyl phosphite is added in step (3). It comprises the following steps: (1) 10.81 g of m-cresol is dissolved in 69.05 g of 2,3-dimethylbutanedinitrile, 7.12 g of PCl3 is slowly added dropwise, and the first solution is obtained after stirring at room temperature for 24 h; (2) 5.26 g of NiI2 and 1.82 g of ZnI2 are dissolved in 69.05 g of 2,3-dimethylbutanedinitrile, 4.53 g of KCN is added as a cyanide source after stirring at 63 °C for 3 h, and the second dehydration solution is obtained after stirring for 3 h until uniform and then dehydrating water at 105 °C under the condition of 10 kPa; (3) The second dehydration solution is added to the first solution under the condition of continuously introducing dry ammonia at a rate of 35 SCCM, and m-cresylnitrile is obtained after the hydrocyanation reaction is carried out at 120 °C under the condition of atmospheric reflux for 18 h.
[0044] The conversion rate of each alkyl-substituted phenolic compound in the above Examples 1-4 and Comparative Examples 1-4, the yield of the intermediate halogenated hydrocarbon in step (1), the yield of the aromatic nitrile prepared in step (3), and the total yield are shown in Table 1.
[0045] Table 1
[0046] As can be seen from the data in Table 1, when the yield of the intermediate halogenated hydrocarbon obtained in step (1) is higher than 70% using the method for preparing aromatic nitrile from the alkyl-substituted phenolic compound of the present application, the yield of the aromatic nitrile obtained in step (3) can be more than 60%, and the total yield is higher than 48%. At the same time, the method for preparing aromatic nitrile from the alkyl-substituted phenolic compound of the present application needs to meet certain conditions: dehydration needs to be carried out in step (2) of the preparation method of the present application, if not, such as Comparative Example 1, the yield of the aromatic nitrile is only 3.13%, so the dehydration treatment in step (2) plays an important role in improving the yield of the aromatic nitrile; the hydrocyanation reaction in step (3) of the preparation method of the present application needs to be carried out under the condition of introducing ammonia, if not, such as Comparative Example 2 under the condition of atmospheric air, the yield of the aromatic nitrile is significantly lower than that of Example 2 under the condition of ammonia; nickel salt and zinc salt need to be added at the same time in step (2) of the preparation method of the present application, if not, such as Comparative Example 3, it directly affects the yield of the aromatic nitrile, therefore, the absence of any one of the salts will directly affect the yield of the aromatic nitrile; the reaction aid needs to be added when the hydrocyanation reaction is carried out in step (3) of the preparation method of the present application, if not, such as Comparative Example 4, the yield of the aromatic nitrile is only 11.29%.
[0047] It should be noted that the above is a further detailed description of the present application in combination with specific embodiments, and the specific implementation of the present application cannot be limited to these descriptions; the data parameters of the present embodiment do not limit the technical solutions, but only show one specific working condition. For ordinary skilled persons in the technical field to which the present application belongs, without departing from the concept of the present application, a number of simple improvements and refinements can be made, which should be regarded as falling within the scope of protection of the present application.
Claims
1. A method for preparing aromatic nitrile from alkyl-substituted phenolic compounds, characterized in that, Includes the following steps: (1) Dissolve alkyl-substituted phenolic compounds in nitrile solvents, add phosphorus trihalides and stir to obtain the first solution; (2) Dissolve nickel salt and zinc salt in a nitrile solvent, stir, add cyanide, and after two stirrings and dehydration, obtain a second dehydrated solution; (3) Under the condition of ammonia gas, the second dehydration solution and reaction aid are added to the first solution to carry out hydrocyanation reaction to prepare aromatic nitrile compounds.
2. The method for preparing aromatic nitrile from alkyl-substituted phenolic compounds according to claim 1, characterized in that, The general formula of the alkyl-substituted phenolic compound mentioned in step (1) is R. 1~5 -Ar-OH; where R 1~5 It is one or more of five sites on the benzene ring that can be substituted, and the substituent at each site is independently selected from hydrogen atoms or straight-chain or branched alkyl groups, having a carbon number of C1 to C20, preferably monosubstituted or disubstituted alkylphenols, and the substituent at each site is independently selected from straight-chain or branched alkyl groups having a carbon number of C1 to C5, further preferably any one of methylphenol, ethylphenol, and dimethylphenol; And / or, the general structural formula of the phosphorus trihalide mentioned in step (1) is PX3, where X is any one of Cl, Br, and I.
3. The method for preparing aromatic nitrile from alkyl-substituted phenolic compounds according to claim 1, characterized in that, The nitrile solvents used in steps (1) and (2) are the same. The nitrile solvents are high-boiling-point nitrile solvents with a boiling point higher than 200°C, preferably one or more of ethyl succinic anionyl, methyl glutaronitrile, 2,3-dimethyl succinic anionyl or adiponitrile.
4. The method for preparing aromatic nitrile from alkyl-substituted phenolic compounds according to claim 1, characterized in that, The nickel salt mentioned in step (2) includes one or more of NiCl2, NiI2, and NiBr2; And / or, the zinc salt mentioned in step (2) includes one or more of ZnCl2, ZnBr2, and ZnI2; And / or, the cyanide mentioned in step (2) includes one or more of KCN, NaCN, Zn(CN)2, K4[Fe(CN)6], and Ni(CN)2.
5. The method for preparing aromatic nitrile from alkyl-substituted phenolic compounds according to claim 1, characterized in that, The reaction aid mentioned in step (3) is one or more of the following: trimethyl phosphite, triethyl phosphite, tricresyl phosphite, tri(2,4-dimethyl)phenyl phosphite, tri(3,5-dimethyl)phenyl phosphite, xylene-phenyl phosphite, and toluene-diphenyl phosphite, preferably one or more of the following: trimethyl phosphite, tricresyl phosphite, triethyl phosphite, or xylene-phenyl phosphite.
6. The method for preparing aromatic nitrile from alkyl-substituted phenolic compounds according to claim 1, characterized in that, The molar ratio of the alkyl-substituted phenolic compound in step (1) to the phosphorus trihalide in step (1) is 1:(0.5~2.25). And / or, the molar ratio of the alkyl-substituted phenolic compound in step (1) to the nickel salt in step (2) is (1~10):1; And / or, the molar ratio of the alkyl-substituted phenolic compound in step (1) to the zinc salt in step (2) is (1~30):1; And / or, the molar ratio of the alkyl-substituted phenolic compound in step (1) to the cyanide in step (2) is (1~1.75):
1.
7. The method for preparing aromatic nitrile from alkyl-substituted phenolic compounds according to claim 1, characterized in that, The molar ratio of the alkyl-substituted phenolic compound in step (1) to the nitrile solvent in steps (1) and (2) is 1:(5~60). And / or, the molar ratio of the alkyl-substituted phenolic compound in step (1) to the reaction aid in step (3) is (1~50):
1.
8. The method for preparing aromatic nitrile from alkyl-substituted phenolic compounds according to claim 1, characterized in that, The stirring temperature in step (1) is room temperature, and the stirring time is 1~72h.
9. The method for preparing aromatic nitrile from alkyl-substituted phenolic compounds according to claim 1, characterized in that, The stirring in step (2) and the second stirring are at the same temperature, which is 15~105℃, and the stirring time is 1~10h; And / or, the stirring time in step (2) is 1~10h; And / or, the secondary stirring time in step (2) is 1~6h; And / or, the dehydration temperature in step (2) is 20~105℃ and the dehydration pressure is 1~10kPa.
10. The method for preparing aromatic nitrile from alkyl-substituted phenolic compounds according to claim 1, characterized in that, The temperature of the hydrocyanation reaction in step (3) is 60~255℃ and the time is 1~72h; And / or, the ammonia gas introduction rate in step (3) is 5~50 sccm.