CN110003047A - A kind of acetone cyanohydrin reacts the method for preparing nitrile with alkyl halide - Google Patents

Abstract

The invention provides a method for preparing nitrile by reacting acetone cyanohydrin and halogenated alkyl. The invention uses acetone cyanohydrin as the cyanating reagent, and solves the problem of using highly toxic sodium cyanide, potassium cyanide or expensive trimethylsilicon cyanide as the cyanide source in the existing preparation method, the reaction time is long, and the yield is relatively high. low temperature and strict reaction conditions. Method: Dissolve acetone cyanohydrin in a mixed solvent composed of aprotic high-boiling dipolar solvent and aprotic low-boiling solvent, add catalyst lithium hydroxide, stir at 25-50°C for one hour, add haloalkane, and continue the reaction For 2-3 hours, add saturated brine to wash twice, separate the organic layer, and after drying, evaporate the solvent to obtain nitrile compounds. The method for preparing the nitrile compound of the invention has the advantages of less reaction toxicity, simple process, easy operation, low production cost and a yield of more than 95%.

Description

A kind of method for preparing nitrile by reaction of acetone cyanohydrin and haloalkane

technical field

The invention belongs to the technical field of organic synthesis, and relates to a method for preparing nitrile by reacting acetone cyanohydrin and halogenated alkyl.

Background technique

Nitrile is a class of organic compounds containing cyano groups. It is an important chemical raw material and has important applications in the fields of medicine and new materials. Among them, representative compounds such as adiponitrile are the raw materials for the preparation of nylon 66, and phenylacetonitrile is the raw material for the production of various Intermediates of medicines and pesticides; acrylonitrile can be copolymerized with other monomers to produce synthetic rubber and engineering plastics, etc.

There are many existing methods for preparing nitrile, but the most commonly used method is the nucleophilic substitution reaction of aliphatic halogenated hydrocarbon and metal cyanide to prepare nitrile. The limitations of this method mainly include (1) the metal cyanide is highly toxic sodium cyanide and potassium cyanide, resulting in serious environmental pollution and personal safety problems; (2) sodium cyanide/potassium cyanide It is an inorganic salt and is almost insoluble in organic solvents. It is necessary to add a phase transfer catalyst, such as tetrabutylammonium bromide, cetyltrimethylammonium, 18 crown 6 ether, etc., which increases the production cost; (3) when the reactant When it is tertiary halogenated alkane, the reaction is mainly to eliminate the product, resulting in lower yield of the substituted product; (4) when the reactant is a halogenated alkane with weak reactivity such as chloroalkane or brominated alkane, it is necessary to add potassium iodide or iodide Sodium as cocatalyst. In order to overcome the above-mentioned defects of this reaction, trimethylsilyl cyanide is used as the cyanating reagent in the laboratory at present, but this substance is expensive and has low atomic utilization rate. The reaction needs to be carried out under strict anhydrous and oxygen-free conditions, so it cannot meet the Industrial production requirements.

Use acetone cyanohydrin, which is relatively safe, to replace hydrocyanic acid (human lethal dose is 0.57mg/kg), sodium cyanide, potassium cyanide (LD50 of acetone cyanohydrin is 52mg/kg, and LD50 of sodium cyanide is 6mg /kg) and other highly toxic cyanating reagents, to avoid problems such as environmental pollution and personal safety; Reagents will greatly reduce production costs and have more practical value. Existing with acetone cyanohydrin as cyanogen source, the method that prepares cyanide through the nucleophilic substitution reaction of halogenated alkyl is less, and the catalyzer used in the existing report is uncommon organic strong base tetramethyl guanidine or is afraid of water, easy to use. flammable lithium hydride, etc.

SUMMARY OF THE INVENTION

The present invention is to solve the problem of using highly toxic sodium cyanide, potassium cyanide catalyst or trimethylsilicon cyanide with poor atom economy and high price as cyanogen source and long reaction time when the existing method for preparing nitrile with halogenated alkyl The rate is low and the reaction conditions are strict. Provided is a new method for preparing nitrile by utilizing the nucleophilic substitution reaction of alkyl halide and acetone cyanohydrin.

The present invention utilizes the nucleophilic substitution reaction of acetone cyanohydrin and alkyl halide to prepare the method for nitrile, and the concrete steps are as follows:

Dissolve acetone cyanohydrin in a mixed solvent consisting of aprotic high-boiling dipolar solvent and aprotic low-boiling solvent, add catalyst lithium hydroxide, stir at 25-50 °C for one hour, and add haloalkane, TLC monitors the disappearance of raw materials , washed with water, extracted with ethyl acetate, the ethyl acetate layer was washed with water and saturated brine respectively, dried with anhydrous Na ₂ SO ₄ , filtered and concentrated to obtain the nitrile.

The further described cyanating reagent is acetone cyanohydrin.

Further, the molar ratio of the acetone cyanohydrin to the haloalkane is 1.1-1.5:1.

Further, the catalyst is lithium hydroxide monohydrate, and the molar ratio of lithium hydroxide monohydrate to alkyl halide is 1.1-1.5:1.

Further, the haloalkanes are primary haloalkanes and secondary haloalkanes.

The further described halogenated alkanes are chloroalkanes, bromoalkanes and iodoalkanes, wherein the halogenated alkanes can be but are not limited to the following compounds: benzyl chloride, n-butane chloride, sec-butane chloride, 1,4-di Chlorobutane, 1-chlorooctane, ethyl 3-chloropropionate, 1-chloro-2-phenylethane, 3-chloropropionitrile, 1,2-dichloroethane, chlorododecane; bromine n-butane, sec-bromobutane, 1,4-dibromobutane, 1-bromo-3-phenylpropane, 3-bromopropionitrile, benzyl bromide, 3-bromo-propionic acid methyl ester, 1 -Bromoethylbenzene, 4-bromobutyric acid methyl ester, bromo-octane, bromooctadecane, diphenylbromomethane, 2-bromopentane, 7-bromoheptanoic acid ethyl ester, 1,2-dibromo Ethane; iodo-n-butane, iodo-n-octane, iodo-tetradecane.

Further, the reaction temperature is 25-50°C, preferably 50°C.

Further, the reaction solvent is a mixed solvent composed of aprotic high-boiling dipolar solvent and aprotic low-boiling solvent, wherein the aprotic high-boiling dipolar solvent is 1,3-dimethylimidazolidinone, N- Methylpyrrolidone, hexamethylphosphoric triamide; low boiling point solvents are dichloromethane, chloroform, acetone, acetonitrile, tetrahydrofuran, diethyl ether.

Further, the ratio of the mixed solvent is that the volume ratio of the aprotic high-boiling dipolar solvent to the aprotic low-boiling solvent is 1:2-1:7, preferably 1:3.

The reaction principle of the invention is as follows: under the catalysis of monohydrate lithium hydroxide, acetone cyanohydrin can undergo nucleophilic substitution reaction with haloalkane to prepare nitrile.

Beneficial effects of the present invention:

The invention uses acetone cyanohydrin as the cyanogen source, which replaces the highly toxic sodium cyanide and potassium cyanide, and replaces the expensive cyanating reagents such as trimethyl cyanosilane.

The reaction conditions of the invention are mild, the reaction time is short, and the reaction yield reaches more than 95%.

The invention uses low-cost monohydrate lithium hydroxide as a catalyst, has simple process and low production cost.

Description of drawings

Fig. 1 is the hydrogen nuclear magnetic resonance spectrum of phenylacetonitrile in embodiment one;

Fig. 2 is the carbon nuclear magnetic resonance spectrum of phenylacetonitrile in embodiment one;

Fig. 3 is the infrared spectrum of phenylacetonitrile in Example 1.

Fig. 4 is the hydrogen nuclear magnetic resonance spectrum of succinonitrile in embodiment ten;

Fig. 5 is the carbon nuclear magnetic resonance spectrum of succinonitrile in embodiment ten;

Figure 6 is the infrared spectrum of succinonitrile in Example 10.

Detailed ways

The technical solutions of the present invention are not limited to the specific embodiments listed below, but also include any combination of specific embodiments.

Embodiment 1: This embodiment utilizes acetone cyanohydrin and halogenated alkyl to react to prepare the method for nitrile, and the specific steps are as follows:

Dissolve acetone cyanohydrin in a mixed solvent consisting of aprotic high-boiling dipolar solvent and aprotic low-boiling solvent, add catalyst lithium hydroxide, stir at 25-50 °C for one hour, and add haloalkane, TLC monitors the disappearance of raw materials , washed with water, extracted with ethyl acetate, the ethyl acetate layer was washed with water and saturated brine respectively, dried with anhydrous Na ₂ SO ₄ , filtered and concentrated to obtain the nitrile.

Embodiment 2: The difference between this embodiment and Embodiment 1 is that the reaction solvent is a mixed solvent composed of 1,3-dimethylimidazolidinone and tetrahydrofuran. Others are the same as the first embodiment.

Embodiment 3: The difference between this embodiment and Embodiment 1 is that the reaction solvent is a mixed solvent composed of 1,3-dimethylimidazolidinone and dichloromethane. Others are the same as the first embodiment.

Embodiment 4: The difference between this embodiment and Embodiment 1 is that the reaction solvent is a mixed solvent composed of N-methylpyrrolidone and acetone; others are the same as Embodiment 1.

Embodiment 5: The difference between this embodiment and Embodiment 1 is that the volume ratio of the mixed solvent composed of 1,3-dimethylimidazolidinone and tetrahydrofuran is 1:2. Others are the same as the first embodiment.

Embodiment 6: The difference between this embodiment and Embodiment 1 is that the volume ratio of the mixed solvent composed of 1,3-dimethylimidazolidinone and tetrahydrofuran is 1:5. Others are the same as the first embodiment.

Embodiment 7: The difference between this embodiment and Embodiment 1 is that the volume ratio of the mixed solvent composed of 1,3-dimethylimidazolidinone and tetrahydrofuran is 1:7. Others are the same as the first embodiment.

Embodiment 8: The difference between this embodiment and Embodiment 1 is that the molar ratio of the catalyst monohydrate lithium hydroxide to the haloalkane is 1.3:1. Others are the same as the first embodiment.

Embodiment 9: The difference between this embodiment and Embodiment 1 is that the molar ratio of the catalyst monohydrate lithium hydroxide to the haloalkane is 1.5:1. Others are the same as the first embodiment.

Embodiment 10: The difference between this embodiment and Embodiment 1 is that the molar ratio of acetone cyanohydrin to alkyl halide is 1.2:1. Others are the same as the first embodiment.

Embodiment 11: This embodiment is different from Embodiment 1 in that the molar ratio of acetone cyanohydrin to alkyl halide is 1.5:1. Others are the same as the first embodiment.

Embodiment 12: This embodiment is different from Embodiment 1 in that the reaction temperature is 50°C. Others are the same as the first embodiment.

Specific embodiment thirteen: The difference between this embodiment and one of specific embodiments one to twelve is that the halogenated alkane is benzyl chloride, chloro-n-butane, chloro-sec-butane, 1,4-dichlorobutane, 1 -Chlorooctane, ethyl 3-chloropropionate, 1-chloro-2-phenylethane, 3-chloropropionitrile, 1,2-dichloroethane, chlorododecane; bromo-n-butane, Bromo-sec-butane, 1,4-dibromobutane, 1-bromo-3-phenylpropane, 3-bromopropionitrile, benzyl bromide, 3-bromo-propionic acid methyl ester, 1-bromoethylbenzene , 4-bromobutyric acid methyl ester, bromo-octane, bromooctadecane, diphenylbromomethane, 2-bromopentane, 7-bromoheptanoic acid ethyl ester, 1,2-dibromoethane; iodo n-Butane, iodo-octane, iodo-tetradecane. Others are the same as one of Embodiments 1 to 12.

The embodiments of the present invention are described in detail below. The following embodiments are implemented on the premise of the technical solutions of the present invention, and provide detailed embodiments and specific operation processes, but the protection scope of the present invention is not limited to the following implementations example.

Example 1:

The method for preparing nitrile with acetone cyanohydrin and haloalkane reaction is characterized in that the method concrete steps are as follows:

Dissolve 1.5mol acetone cyanohydrin in a mixed solvent composed of 1,3-dimethylimidazolidinone and tetrahydrofuran (volume ratio is 1:3), add 1.5mol catalyst lithium hydroxide monohydrate, and stir at 50°C for one hour After adding 1mol of benzyl bromide, TLC monitored the disappearance of the raw materials, washed with water, extracted with ethyl acetate, washed the ethyl acetate layer with water and saturated brine respectively, dried with anhydrous Na ₂ SO ₄ , filtered and concentrated to obtain phenylacetonitrile product . The reaction time was 2.5h, and the yield was 97%.

The H NMR spectrum of phenylacetonitrile ( _300MHZ , _CDCl3 , in ppm) is shown in Figure 1: 7.39-7.32 (m, 5H), 3.75 (s, 2H).

The carbon nuclear magnetic resonance spectrum of phenylacetonitrile (75MH _Z , CDCl ₃ , unit ppm) is shown in Figure 2: 129.9, 128.9, 127.8, 127.7, 117.8, 23.3

The infrared spectrum of phenylacetonitrile (KBr coating method, unit: cm ^-1 ) is shown in Figure 3: 3068, 3034, 2251, 1603, 1497, 1454, 1417, 1078, 1030, 740

Combining the hydrogen spectrum, carbon spectrum and infrared spectrum of the compound, it can be seen that the structure of the synthesized compound is correct.

Example 2: All experimental conditions and processing methods in this example are the same as those in Example 1, except that the benzyl bromide is changed to benzyl chloride, the reaction time is 4.5h, and the yield is 95.6%.

Example 3: All experimental conditions and processing methods in this example are the same as those in Example 1, except that the mixed solvent composed of 1,3-dimethylimidazolidinone and tetrahydrofuran was changed to 1,3-dimethylimidazolidinone and tetrahydrofuran. The mixed solvent composed of dichloromethane, the reaction time was 5.5h, and the yield was 95.7%.

Example 4: All experimental conditions and processing methods in this example are the same as in Example 1, except that the mixed solvent composed of 1,3-dimethylimidazolidinone and tetrahydrofuran is changed to a mixed solvent composed of N-methylpyrrolidone and acetone , the reaction time was 3.5h, and the yield was 96.3%.

Example 5: All experimental conditions and processing methods in this example are the same as those in Example 1, except that the mixed solvent composed of 1,3-dimethylimidazolidinone and tetrahydrofuran is changed to a mixture composed of hexamethylphosphoric triamide and diethyl ether. mixed solvent, the reaction time was 5h, and the yield was 95.2%.

Example 6: All experimental conditions and processing methods in this example are the same as in Example 1, except that the volume ratio of the mixed solvent composed of 1,3-dimethylimidazolidinone and tetrahydrofuran was changed from 1:3 to 1:5, The reaction time was 3.5 h, and the yield was 96.7%.

Example 7: All experimental conditions and treatment methods in this example are the same as in Example 1, except that the molar ratio of the catalyst lithium hydroxide monohydrate to benzyl bromide 1.5:1 was changed to 1.3:1, the reaction time was 4.5h, and The rate was 96.2%.

Example 8: All experimental conditions and processing methods in this example are the same as in Example 1, except that the molar ratio of acetone cyanohydrin to benzyl bromide was changed from 1.5:1 to 1.2:1, the reaction time was 4h, and the yield was 95.9 %.

Example 9: All experimental conditions and treatment methods in this example are the same as those in Example 1, except that the temperature was changed from 50°C to 25°C, the reaction time was 5h, and the yield was 95.3%.

Example 10: All experimental conditions and processing methods in this example are the same as in Example 1, except that the benzyl bromide is changed to 3-chloropropionitrile, the reaction time is 3.5h, and the yield is 98%. The H NMR spectrum of the product succinonitrile (300MH _Z , CDCl ₃ , unit ppm) is shown in Figure 4: 2.76 (s, 4H); the C NMR spectrum of succinonitrile (75MH _Z , CDCl ₃ , unit ppm) As shown in Figure 5: 116.2, 14.7; the infrared spectrum of succinonitrile (KBr coating method, unit: cm ^-1 ) is shown in Figure 6: 3465, 2989, 2955, 2254, 1427, 1003, 964, 822, 762, 605.

Example 11: All experimental conditions and processing methods in this example were the same as those in Example 1, except that the benzyl bromide was changed to 1-chloro-2-phenylethane, the reaction time was 2.5h, and the yield was 97.9%. 1H NMR data of the product phenylpropionitrile (300MH _Z , CDCl ₃ , unit ppm): 7.36-7.24 (m, 5H), 2.97 (t, J=7.36Hz, 2H), 2.63 (t, J=7.40Hz) , 2H); CNMR data of phenylpropionitrile (75MH _Z , CDCl ₃ , unit ppm): 138.1, 128.9, 128.2, 127.2, 119.1, 31.5, 19.3; FTIR data of phenylpropionitrile (KBr coating method , unit: cm ^-1 ): 3087, 3069, 3030, 2868, 2246, 1604, 1496, 1454, 1425, 1079, 1340, 749.

Example 12: All experimental conditions and processing methods in this example were the same as those in Example 1, except that the benzyl bromide was changed to ethyl 3-chloropropionate, the reaction time was 3.5h, and the yield was 95.9%. 1H NMR data of the product ethyl 3-cyanopropionate (300MHz, CDCl3, unit ppm): 4.19 (q, J=7.09Hz, 2H), 2.65 (s, 4H), 1.27 (t, J=7.13 Hz, 3H); CNMR data of ethyl 3-cyanopropionate ( _75MHZ , _CDCl3 , in ppm): 170.0, 118.5, 61.5, 30.0, 14.1, 12.6; ethyl 3-cyanopropionate Infrared spectral data (KBr coating method, unit: cm ^-1 ): 2927, 2854, 2251, 1736, 1691, 1422, 1377, 1199, 1114, 1018, 854, 617.

Example 13: All experimental conditions and processing methods in this example are the same as those in Example 1, except that the benzyl bromide is changed to chlorooctadecane, the reaction time is 4.5h, and the yield is 95.1%. NMR data of the product N-nonadecyl nitrile (300MHz, CDCl3, unit ppm): 2.33 (t, J=7.03, 2H), 1.68-1.63 (m2H), 1.49-1.44 (m, 2H), 1.26(s, 28H), 0.88(t, J=5.54Hz, 3H); CNMR data of N-nonadecyl nitrile (75MH _Z , CDCl ₃ , unit ppm): 119.9, 32.0, 29.7, 29.6 , 29.4, 28.8, 28.7, 25.4, 22.7, 17.2, 14.2; Infrared spectral data of N-nonadecyl nitrile (KBr coating method, unit: cm ^-1 ): 3064, 3032, 2987, 2938, 2877, 2242 , 1958, 1896, 1669, 1385, 752, 570.

Example 14: All experimental conditions and treatment methods in this example are the same as those in Example 1, except that the benzyl bromide is changed to diphenyl bromide, the reaction time is 4.5h, and the yield is 95.2%. 1H NMR data of the product diphenylacetonitrile (300MH _Z , CDCl ₃ , unit ppm): 7.35 (m, 10H), 5.14 (s, 1H); 1H NMR data of the product diphenylacetonitrile (75MH _Z , CDCl _{3 )} , unit ppm): 135.9, 129.2, 128.3, 127.8, 42.8; Infrared spectral data of diphenylacetonitrile (KBr tablet method, unit: cm ^-1 ) 3027, 2933, 2852, 2243, 1658, 1597, 1492, 1118, 1079,744,697,540.

Example 15: All experimental conditions and treatment methods in this example are the same as those in Example 1, except that the benzyl bromide is changed to 1-bromo-3-phenylpropane, the reaction time is 3h, and the yield is 96%. NMR data of the product 4-phenylbutyronitrile (300MHZ, _CDCl3 , unit ppm): 7.36-7.17 (m, 5H), 2.80-2.75 (t, J= _7.40Hz , 2H), 2.34-2.29 (t, J=7.09Hz, 2H), 2.00-1.95 (m, 2H),; 4-phenylbutyronitrile CNMR data (75MH _Z , CDCl ₃ , unit ppm): 139.7, 128.6, 128.4, 126.5 , 119.5, 34.3, 26.9, 16.3; 4-phenylbutyronitrile infrared spectrum data (KBr coating method, unit: cm ^-1 ): 3085, 3069, 3029, 2928, 2867, 2246, 1603, 1497, 1455, 1425 , 1082, 1030, 748, 701.

Example 16: All experimental conditions and processing methods in this example are the same as those in Example 1, except that the benzyl bromide is changed to ethyl 7-bromoheptanoate, the reaction time is 4h, and the yield is 96.8%. Product ethyl 7- _{cyanoheptanoate} : 1H NMR data (300MHZ, _CDCl3 , in ppm): 4.15-4.11 (q, J=7.02Hz, 2H), 2.34-2.27 (t, J=11.72 Hz, 4H), 1.66-1.61(m, 4H), 1.47-1.40(t, J=5.39Hz 2H), 1.38-1.35(m, 2H), 1.27-1.22(t, J=7.04Hz, 3H); Carbon NMR data for ethyl 7-cyanoheptanoate ( _75MHZ , _CDCl3 , in ppm): 173.4, 119.6, 132.4, 60.1, 34.0, 28.2, 28.1, 25.0, 24.4, 16.9, 14.1; 7-cyano Infrared spectral data of ethyl heptanoate (KBr coating method, unit: cm ^-1 ): 2936, 2863, 2245, 1732, 1464, 1373, 1252, 1187, 1096, 1033.

Example 17: All experimental conditions and processing methods in this example are the same as those in Example 1, except that the benzyl bromide is changed to 1,4-dibromobutane, the reaction time is 3h, and the yield is 97.9%. The H NMR spectrum of the product adiponitrile (300MH _Z , CDCl ₃ , unit ppm): 2.44-2.41 (m, 4H); 1.83-1.81 (m, 4H); the C NMR spectrum of adiponitrile (75 MH _Z , CDCl ₃ , unit ppm): 118.72, 24.21, 16.59; infrared spectrum of adiponitrile (KBr coating method, unit: cm ⁻¹ ): 2949, 2881, 2249, 1697, 1462, 1427, 1335, 898,766.

Example 18: All experimental conditions and processing methods in this example are the same as those in Example 13, except that 1,4-dibromobutane was changed to 1,4-dichlorobutane, the reaction time was 4.5h, and the yield was 95.3 %.

Example 19: All experimental conditions and processing methods in this example were the same as those in Example 1, except that the benzyl bromide was changed to methyl 3-bromopropionate, the reaction time was 3.5h, and the yield was 98.2%. The NMR spectrum of the product methyl 3-cyanopropionate (300MH _Z , CDCl ₃ , unit ppm): 3.73 (s, 3H), 2.70-2.61 (m, 4H); Carbon NMR spectrum (75MH _Z , CDCl ₃ , unit ppm): 170.4, 118.4, 52.3, 29.8, 13.0; Infrared spectrum of methyl 3-cyanopropionate (KBr coating method, unit: cm ^-1 ): 3328 , 2959, 2251, 1667, 1576, 1506, 1387, 1279, 1181, 950, 883, 682.

Example 20: All experimental conditions and processing methods in this example are the same as those in Example 1, except that the benzyl bromide is changed to n-butane iodide, the reaction time is 3.5h, and the yield is 95.5%. H NMR data of the product valeronitrile (300MHZ, _CDCl3 , unit ppm): 2.34 (t, J= _7.02Hz , 2H), 1.67-1.59 (m, 2H), 1.52-1.44 (m, 2H), 0.92 (t, J=7.20Hz, 3H); carbon NMR data of valeronitrile (75MH _Z , CDCl ₃ , unit ppm): 119.8, 27.4, 21.8, 16.8, 13.2; infrared spectrum data of valeronitrile (KBr coated Membrane method, unit: cm ^-1 ): 2992, 2941, 2243, 1460, 1382, 1190, 1141, 976, 876, 696, 596, 475.

Example 21: All experimental conditions and processing methods in this example were the same as those in Example 1, except that the benzyl bromide was changed to n-octane iodide, the reaction time was 3.5h, and the yield was 97.2%. The 1H NMR data (300MH _Z , CDCl ₃ , unit ppm) of the product nononitrile: 2.35-2.30 (t, J=7.06Hz, 2H), 1.69-1.60 (m, 2H), 1.43-1.41 (m, 2H) ), 1.30-1.27 (m, 8H), 0.87-0.85 (t, J=6.62Hz, 3H); carbon nuclear magnetic resonance data of the product nononitrile (75MH _Z , CDCl ₃ , unit ppm): 119.9, 31.7, 29.0 , 28.7, 22.6, 17.1, 14.1; Infrared spectral data of the product anonitrile (KBr coating method, unit: cm ^-1 ): 2927, 2856, 2246, 1466, 1427, 1377, 723.

Example 22: All experimental conditions and treatment methods in this example are the same as those in Example 1, except that the benzyl bromide is changed to iodotetradecane, the reaction time is 3h, and the yield is 96.6%. H NMR data of the product pentadecanenitrile (300MH _Z , CDCl ₃ , unit ppm): 2.33 (t, J=7.09Hz, 2H), 1.68-1.63 (m, 2H), 1.44-1.41 (m, 2H), 1.25(s, 20H), 0.88(t, J=6.17Hz, 3H); CNMR data of pentadecanenitrile (75MH _Z , CDCl ₃ , unit ppm): 119.8, 31.9, 29.7, 29.6 , 29.5, 29.4, 29.3, 28.7, 25.4, 22.7, 17.1, 14.1; Infrared spectral data of pentadecanenitrile (KBr coating method, unit: cm ^-1 ): 2926, 2854, 2247, 1686, 1466, 1427, 1378, 1297, 722.

The structure data of the products in Examples 10-22 indicated that the structures of the synthesized compounds were correct.

Claims (9)

1. a kind of acetone cyanohydrin reacts the method for preparing nitrile with alkyl halide, it is characterised in that specific step is as follows for this method:

It is molten that acetone cyanohydrin is dissolved in the mixing being made of aprotic higher boiling dipole solvent and aprotic low boiling point solvent In agent, it is added catalyst lithium hydroxide, 25-50 DEG C is added alkyl halide after stirring one hour, and TLC is monitored after raw material disappears, and adds water Washing, ethyl acetate extraction, ethyl acetate layer use water and saturated common salt water washing respectively again, use anhydrous Na₂SO₄It is filtered after drying It is concentrated to get nitrile.

2. synthetic method according to claim 1, it is characterised in that the cyanating reagent is acetone cyanohydrin.

3. synthetic method according to claim 1, it is characterised in that the molar ratio of acetone cyanohydrin and alkyl halide is 1.1- 1.5:1。

4. synthetic method according to claim 1, it is characterised in that the catalyst is monohydrate lithium hydroxide, monohydrate The molar ratio of lithium hydroxide and alkyl halide is 1.1-1.5:1.

5. synthetic method according to claim 1, it is characterised in that the alkyl halide is primary alkyl halide and secondary alkyl halide.

6. according to claim 1 with synthetic method described in 5, it is characterised in that the alkyl halide be alkyl chloride, bromoalkane and iodine For alkane, wherein alkyl halide can be, but not limited to, following compounds: benzyl chloride, chloro-normal butane, chloro-chung butane, Isosorbide-5-Nitrae-two The chloro- 2- vinylbenzene of chlorobutane, 1- chloro-octane, 3- chloropropionate, 1-, 3- chloroethyl nitrile, 1,2- dichloroethanes, chlorinated dodecane； The bromo- 3- phenyl-propane of bromination of n-butane, chung-bromo butane, 1,4- dibromobutane, 1-, 3- bromopropionitrile, cylite, the bromo- propionic acid of 3- Methyl esters, 1- bromo ethyl phenenyl, 4- bromo butyric acid methyl ester, n-octane bromide, bromo-octadecane, diphenyl-bromomethane, 2 bromo pentane, 7- bromine heptan Acetoacetic ester, glycol dibromide；Iodo-n-butane, iodo normal octane, iododecane.

7. synthetic method according to claim 1, it is characterised in that reaction temperature is 25-50 DEG C, preferably 50 DEG C.

8. synthetic method according to claim 1, it is characterised in that the reaction dissolvent is aprotic higher boiling dipole The mixed solvent of solvent and aprotic low boiling point solvent, wherein aprotic higher boiling dipole solvent is 1,3- methylimidazole Quinoline ketone, N-Methyl pyrrolidone, hexamethylphosphoramide；Low boiling point solvent is methylene chloride, chloroform, acetone, acetonitrile, four Hydrogen furans, ether.

9. according to claim 1 and synthetic method described in 6,7, it is characterised in that the ratio of the mixed solvent is aprotic The volume ratio of higher boiling dipole solvent and aprotic low boiling point solvent is 1:2-1:7, preferably 1:3.