CN107556214B - A kind of preparation method of paracyanobenzoic acid - Google Patents
A kind of preparation method of paracyanobenzoic acid Download PDFInfo
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Abstract
The invention discloses a kind of preparation methods of paracyanobenzoic acid.This method is to prepare intermediate product 4- cyano benzyl alcohol by hydrolysis under alkaline condition using 4- chloromethyl cyanophenyl as raw material, and phase transfer catalyst, activator, oxidant and catalyst is added, oxidation reaction 4-15h is carried out at 50-100 DEG C, obtains finished product.The present invention uses specific phase transfer catalyst and catalyst in the oxidation reaction, and salt is added as the activator of phase transfer catalyst, the oxidation time of intermediate product 4- cyano benzyl alcohol is foreshortened to 6-10 hours, the yield of finished product 4- chloromethyl cyanophenyl reaches 86.4% or more, and purity reaches 98.6% or more.This method is safe and pollution-free, easy to operate, purity is high, the new method suitable for Green Chemistry application.
Description
Technical field
The present invention relates to a kind of preparation methods of paracyanobenzoic acid, belong to chemical production technology field.
Background technique
Paracyanobenzoic acid is a kind of lobate crystallization of white, molecular formula C8H5NO2, molecular weight 147.13, fusing point is
It is 217-222 DEG C, miscible with water section, it is dissolved in alcohol, ether, hot water and glacial acetic acid.Terephthalic acid (TPA) can be generated with thermokalite.To cyano benzene
Intermediate of the formic acid as para-amiunomethylbenzoic acid is used for organic synthesis, liquid crystal polymer synthesis, medicine intermediate etc..
Currently, the production method of paracyanobenzoic acid mainly include the following types:
The first, using 4- chloromethyl cyanophenyl as raw material, concentrated nitric acid is oxidant, synthesizes paracyanobenzoic acid, the synthetic route
Although simple, by-product is excessive, and seriously polluted, the three wastes are not easy to handle, is not suitable for industrial applications.
The second, methanol yl benzoic acid as raw material, is synthesized paracyanobenzoic acid, but in this synthetic method, be made
With formic acid, formic acid corrosivity is strong, is unsuitable for operation.
Third uses ammonia oxidation preparation synthesis paracyanobenzoic acid, but this method has maximum
It is to need very high pressure and temperature in reaction process, will increase industrial equipment requirement, is not suitable for industrialized production.
In conclusion traditional synthetic method is there are reaction process by-product is excessive, it is strong and high using reagent corrosivity
The restrictive conditions such as warm high pressure, it is seen that existing method is not able to satisfy the demand of modern production paracyanobenzoic acid.
Summary of the invention
In view of the above-mentioned prior art the problem of preparing paracyanobenzoic acid, the present invention provides a kind of new to cyanogen
The preparation method of yl benzoic acid, the three wastes that this method energy consumption is lower, side reaction is few, reaction step is simple, reaction generates are easy place
Reason, it is mutually more environmentally protective than existing methods.
Technical scheme is as follows:
A kind of preparation method of paracyanobenzoic acid, includes the following steps:
(1) 4- chloromethyl cyanophenyl is added into the aqueous solution of inorganic base, reaction is hydrolyzed at 50-100 DEG C；
(2) hydrolysis liquid is extracted with organic solvent, collects extract liquor, is removed organic solvent, is obtained intermediate product I；
(3) phase transfer catalyst, activator, oxidant and catalyst are added in the intermediate product I that step (2) obtains,
4-15h is reacted at 50-100 DEG C, is filtered；
Wherein, in step (3), the phase transfer catalyst is methyl tricapryl ammonium chloride, methyl trioctylphosphine sulfuric acid
One of hydrogen ammonium, tetrabutylammonium chloride, 4-butyl ammonium hydrogen sulfate are a variety of；The activator is that the activator is chlorination
One of sodium, sodium sulphate, sodium dihydrogen phosphate, potassium chloride, sodium sulphate；The catalyst is the tungsten according to mass ratio 1-3:1
The mixture of sour sodium dihydrate and vanadic sulfate.
In the above-mentioned technical solutions, the intermediate product I described in step (2) is 4- cyano benzyl alcohol.
In above-mentioned all technical solutions, in step (1), the inorganic base is potassium carbonate, saleratus, hydroxide
One of potassium, sodium carbonate, sodium hydroxide, sodium bicarbonate, calcium hydroxide, ammonium carbonate, ammonium hydroxide.In step (1), 4- chloromethyl
In the presence of an inorganic base, 4 chlorine obtain intermediate product 4- cyano benzyl alcohol by hydroxyl nucleophilic displacement of fluorine to cyanophenyl.The hydrolysis of step (1)
Reaction temperature is preferably 80-86 DEG C.
In above-mentioned all technical solutions, in step (1), the matter of inorganic base and water in the aqueous solution of the inorganic base
For amount than being 1:10-30, preferential 1:15-17, the too low raw material of mass ratio is largely remaining, and the excessively high cyan-hydrolysis of mass ratio is benzoic acid.
In above-mentioned all technical solutions, in step (1), the mass ratio of the 4- chloromethyl cyanophenyl and inorganic base is
5:1-5:4。
In above-mentioned all technical solutions, in step (2), the organic solvent is petroleum ether, ethyl acetate, positive fourth
One of alcohol, hexamethylene, methylene chloride, chloroform, preferably methylene chloride.
In above-mentioned all technical solutions, in step (3), the intermediate product I, phase transfer catalyst, activator,
The molar ratio of oxidant and catalyst is 88-96:1-2:0.018-0.026:305-316:3.0-3.8.
In above-mentioned all technical solutions, in step (3), the reaction dissolvent of the reaction be water, the tert-butyl alcohol, ethyl alcohol,
One of toluene, glacial acetic acid, acetonitrile, preferably water.
In above-mentioned all technical solutions, in step (3), the oxidant is 10%-70% hydrogen peroxide, tert-butyl
One of hydrogen peroxide, sodium hypochlorite, preferably 10%-70% hydrogen peroxide, more preferable 30% hydrogen peroxide.
In above-mentioned all technical solutions, in step (3), after reaction solution filtering, paracyanobenzoic acid crude product is obtained, stone is used
One of oily ether, ethyl acetate, n-butanol, hexamethylene, methylene chloride or chloroform recrystallize to obtain paracyanobenzoic acid finished product.
The wherein preferred methylene chloride of solvent for recrystallization.
Reaction equation when preparing 4- cyanobenzoic acid using method of the invention is as follows, and wherein first step hydrolysis is to adopt
Use sodium bicarbonate as inorganic base, second step oxidation reaction is using, as oxidant, oxidation reaction exists using hydrogen peroxide
It is carried out in the presence of phase transfer catalyst of the present invention, activator and catalyst:
Beneficial effects of the present invention:
(1) specific phase transfer catalyst and catalyst are used in the oxidation reaction, and salt is added as phase
The activator of transfer catalyst can effectively shorten the time required for reaction, improve product purity and yield.Using this
The oxidation time of the method for invention, intermediate product 4- cyano benzyl alcohol foreshortens to 6-10 hours, and energy consumption of reaction is lower, produces eventually
The yield of product 4- chloromethyl cyanophenyl reaches 86.4% or more, and purity reaches 98.6% or more.
(2) reaction step is simple, is not related to the not easy-operating reaction condition such as high pressure-temperature.
(3) three wastes that reaction generates are easily processed, and it is more environmentally protective to compare other methods.
Specific embodiment
The invention will now be further described with reference to specific embodiments, the advantages and features of the present invention will be with description and
It is apparent.But examples are merely exemplary, and it is not intended to limit the scope of the present invention in any way.Those skilled in the art answer
It should be appreciated that without departing from the spirit and scope of the invention can details to technical solution of the present invention and form repair
Change or replace, but these modifications and replacement are fallen within the protection scope of the present invention.In following embodiments, unless otherwise specified,
Used experimental method is conventional method, and material therefor, reagent etc. can be bought from biological or chemical company.
Embodiment 1
Potassium carbonate 138g, 4- chloromethyl cyanophenyl 151.5g and water 2300g are put into 3000mL four-hole bottle.It is heated to 80
DEG C, it reacts 10 hours, HPLC detection is done in sampling, is confirmed that the hydrolysis of 4- chloromethyl cyanophenyl is complete, is added in hydrolysis liquid
Enter methylene chloride point extraction (each 800mL is extracted 3 times at normal temperature), extractant is distilled off in extract liquor, obtains 4- cyanogen
Base benzyl alcohol 128g, purity reach 96-98%, yield: 96.2%.
By 4- cyano benzyl alcohol 128g, methyl trioctylphosphine ammonium hydrogen sulfate 6.2g, sodium tungstate dihydrate 4.6g, vanadic sulfate
4g, sodium chloride 4g, water 500g are put into four-hole bottle, oil bath heating, and temperature is made to rise to 90 DEG C, and 30% dioxygen is added dropwise into kettle
Water 400g.HPLC detection is carried out by sampling, when 4- cyano benzyl alcohol disappears, reaction terminates, and the reaction time is 6h altogether, while hot mistake
Filter, obtains crude product 138g, purity 85%.Recrystallize with dichloromethane is added, obtains product 127g, product purity 98.6%,
Total recovery: 86.4%.
Embodiment 2
Saleratus 10g is added in 250mL four-hole bottle, lower liter is sufficiently stirred in 4- chloromethyl cyanophenyl 15.1g and water 150g
High-temperature is reacted 10 hours, is detected through HPLC to 80 DEG C, and confirmation raw material hydrolyzes fully reacting, and chloroform point extraction is added in reaction solution
(each 100mL is extracted 3 times at normal temperature) is taken, extractant is distilled off in extract liquor, and it is total to obtain intermediate 4- cyano benzyl alcohol
12.6g is counted, purity reaches 93%-95%, yield 94.7%.
4- cyano benzyl alcohol 12.6g, methyl tricapryl ammonium chloride 0.62g, two water of sodium tungstate are put into 500mL four-hole bottle
Object 0.46g, sodium sulphate 0.4g, vanadic sulfate 0.4g, tert-butyl alcohol 50g are closed, raising kettle temperature is slow with micro addition funnel to 80 DEG C
Tert-butyl hydroperoxide 200g is added dropwise, HPLC detection is carried out by sampling, when 4- cyano benzyl alcohol disappears, reaction terminates, and amounts to
15h obtains crude product 13.3g, is recrystallized with n-butanol, obtains product 11.8g, purity 85.2%, yield 80.3%.
Embodiment 3
Potassium hydroxide 10g is added in 250mL four-hole bottle, 4- chloromethyl cyanophenyl 15.1g and water 120g carry out the water of raw material
Solution reaction.Under mechanical stirring, it is heated to reflux (82 DEG C), is detected by HPLC, it is known that raw material is complete when reacting 10h
Full response finishes.Petroleum ether point extraction (each 80mL is extracted 3 times at normal temperature) is added at this time, extraction is distilled off in extract liquor
Solvent is taken, intermediate 4- cyano benzyl alcohol is obtained, amounts to 11.4g, purity reaches 88-92%, yield 85.7%.
In 250mL four-hole bottle, 4- cyano benzyl alcohol 11.4g, tetrabutylammonium chloride 0.62g, sodium tungstate 0.46g is added,
Sodium sulphate 0.4g, vanadic sulfate 0.4g, sodium hypochlorite 60g, ethyl alcohol 50g, reaction temperature are increased to 78 DEG C, are carried out by sampling
HPLC detection, when 4- cyano benzyl alcohol disappears, reaction terminates, and amounts to 10h, obtains crude product 13.1g, reduces temperature to room temperature, second
Acetoacetic ester recrystallization, stirring at normal temperature, filtering can obtain product 11.7g, purity 86.3%, yield 79.6%.
Comparative example 1
Calcium hydroxide 50g, 4- chloromethyl cyanophenyl 15.1g and water 200g are put into 250mL four-hole bottle.It is heated to 80-90
DEG C, it reacts 10 hours, HPLC detection is done in sampling, is confirmed that the hydrolysis of 4- chloromethyl cyanophenyl is complete, is added in hydrolysis liquid
Enter hexamethylene extraction, (each 150mL, at normal temperature extract 3 times) obtains 4- cyano benzyl alcohol 9.8g, and purity is up to 78%, yield:
73.7%.
4- cyano benzyl alcohol 9.8g, methyl tricapryl ammonium chloride 0.62g, vanadic sulfate are put into 250mL four-hole bottle
0.4g, acetonitrile 50g are heated to reflux (82 DEG C), and dropwise addition 70% pair is slowly added dropwise into four-hole bottle with micro addition funnel at this time
Oxygen water 50g, drop finish, and HPLC detection is done in insulation reaction 17h, sampling, and when 4- cyano benzyl alcohol disappears, reaction terminates, hexamethylene weight
Crystallization can obtain 5.2g product, purity 45.6%, yield: 35.4%.
Comparative example 2
Saleratus 20g is added in 500mL four-hole bottle, lower liter is sufficiently stirred in 4- chloromethyl cyanophenyl 30.2g and water 300g
High-temperature is reacted 10 hours, is detected through HPLC to 80 DEG C, and confirmation raw material hydrolyzes fully reacting, and chloroform point extraction is added in reaction solution
(each 100mL is extracted 3 times at normal temperature) is taken, extractant is distilled off in extract liquor, and it is total to obtain intermediate 4- cyano benzyl alcohol
24.8g is counted, purity is up to 93%, yield 93.40%.
4- cyano benzyl alcohol 24.8g, methyl tricapryl ammonium chloride 1.24g, two water of sodium tungstate are put into 500mL four-hole bottle
Object 0.92g, vanadic sulfate 0.8g, tert-butyl alcohol 100g are closed, kettle temperature is increased to 80 DEG C, tert-butyl is slowly added dropwise with micro addition funnel
Hydrogen peroxide 400g carries out HPLC detection by sampling, and when 4- cyano benzyl alcohol disappears, reaction terminates, and amounts to 15h, obtains and slightly produce
Product 26.6g, is recrystallized with n-butanol, obtains product 15.8g, purity 45.2%, yield 53.82%.
Comparative example 3
Calcium hydroxide 50g, 4- chloromethyl cyanophenyl 15.1g and water 200g are put into 250mL four-hole bottle.It is heated to 80-90
DEG C, it reacts 10 hours, HPLC detection is done in sampling, is confirmed that the hydrolysis of 4- chloromethyl cyanophenyl is complete, is added in hydrolysis liquid
Enter hexamethylene extraction, (each 150mL, at normal temperature extract 3 times) obtains 4- cyano benzyl alcohol 9.8g, and purity is up to 78%, yield:
73.7%.
4- cyano benzyl alcohol 9.8g, methyl tricapryl ammonium chloride 0.62g, vanadic sulfate are put into 250mL four-hole bottle
0.4g, sodium sulphate 0.4g, acetonitrile 50g are heated to reflux (82 DEG C), are slowly added dropwise at this time with micro addition funnel into four-hole bottle
70% hydrogen peroxide 50g is added dropwise, drop finishes, and HPLC detection is done in insulation reaction 17h, sampling, when the disappearance of 4- cyano benzyl alcohol, reaction knot
Beam, hexamethylene recrystallization can obtain 7.2g product, purity 45.6%, yield: 49.15%.
Claims (7)
1. a kind of preparation method of paracyanobenzoic acid, includes the following steps:
(1) 4- chloromethyl cyanophenyl is added into inorganic base aqueous solution, reaction is hydrolyzed at 50-100 DEG C；
(2) hydrolysis liquid is extracted with organic solvent, collects extract liquor, is removed organic solvent, is obtained intermediate product I；
(3) phase transfer catalyst, activator, oxidant and catalyst are added in the intermediate product I that step (2) obtains, in 50-
4-15h is reacted at 100 DEG C, is filtered；
Wherein, in step (3), the phase transfer catalyst be methyl tricapryl ammonium chloride, methyl trioctylphosphine ammonium hydrogen sulfate,
One of tetrabutylammonium chloride, 4-butyl ammonium hydrogen sulfate are a variety of；The activator is sodium chloride, sodium sulphate, di(2-ethylhexyl)phosphate
One of hydrogen sodium, potassium chloride；The catalyst is the sodium tungstate dihydrate and vanadic sulfate according to mass ratio 1-3:1
Mixture；
In step (1), the inorganic base is potassium carbonate, saleratus, potassium hydroxide, sodium carbonate, sodium hydroxide, bicarbonate
One of sodium, calcium hydroxide, ammonium carbonate, ammonium hydroxide；
In step (3), the oxidant is 10%-70% hydrogen peroxide, tert-butyl hydroperoxide, one in sodium hypochlorite
Kind.
2. preparation method according to claim 1, which is characterized in that in the aqueous solution of the inorganic base inorganic base with
The mass ratio of water is 1:10-30.
3. preparation method according to claim 1, which is characterized in that in step (1), the 4- chloromethyl cyanophenyl with
The mass ratio of inorganic base is 5:1-5:4.
4. preparation method according to claim 1, which is characterized in that in step (2), the organic solvent is petroleum
One of ether, ethyl acetate, n-butanol, hexamethylene, methylene chloride, chloroform.
5. preparation method according to claim 1, which is characterized in that in step (3), the intermediate product I, phase turn
Shifting catalyst, activator, oxidant and catalyst molar ratio be 88-96:1-2:0.018-0.026:305-316:3.0-
3.8。
6. preparation method according to claim 1, which is characterized in that in step (3), the reaction dissolvent of the reaction is
One of water, the tert-butyl alcohol, ethyl alcohol, toluene, glacial acetic acid, acetonitrile.
7. preparation method according to claim 1, which is characterized in that in step (3), after reaction solution filtering, obtain to cyanogen
Yl benzoic acid crude product, with one of petroleum ether, ethyl acetate, n-butanol, hexamethylene, methylene chloride or chloroform recrystallize pair
Cyanobenzoic acid finished product.
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| CN112608227B (en) * | 2020-12-02 | 2023-04-18 | 广东石油化工学院 | Method for preparing isononanoic acid from isononanol through green oxidation |
| CN112679384B (en) * | 2021-01-13 | 2023-04-07 | 国药集团化学试剂有限公司 | Preparation method of p-cyanobenzoic acid |
| CN113307740A (en) * | 2021-05-27 | 2021-08-27 | 中瀚(齐河县)生物医药科技有限公司 | Preparation method of 2-amino-4-fluorobenzoic acid |
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| CN103214396A (en) * | 2013-04-10 | 2013-07-24 | 湖北工业大学 | Production method of 3-cyanobenzoic acid |
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| CN103214396A (en) * | 2013-04-10 | 2013-07-24 | 湖北工业大学 | Production method of 3-cyanobenzoic acid |
| CN105237317A (en) * | 2015-10-28 | 2016-01-13 | 衢州群颖化学科技有限公司 | Combined production method for substituted benzaldehyde, substituted benzyl alcohol and substituted benzoic acid |
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