CN107501108B - 4-aminobenzoic acid ethyl ester raw powder's production technology - Google Patents
4-aminobenzoic acid ethyl ester raw powder's production technology Download PDFInfo
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- CN107501108B CN107501108B CN201710632546.2A CN201710632546A CN107501108B CN 107501108 B CN107501108 B CN 107501108B CN 201710632546 A CN201710632546 A CN 201710632546A CN 107501108 B CN107501108 B CN 107501108B
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- aminobenzoic acid
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C227/00—Preparation of compounds containing amino and carboxyl groups bound to the same carbon skeleton
- C07C227/04—Formation of amino groups in compounds containing carboxyl groups
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C227/00—Preparation of compounds containing amino and carboxyl groups bound to the same carbon skeleton
- C07C227/14—Preparation of compounds containing amino and carboxyl groups bound to the same carbon skeleton from compounds containing already amino and carboxyl groups or derivatives thereof
- C07C227/18—Preparation of compounds containing amino and carboxyl groups bound to the same carbon skeleton from compounds containing already amino and carboxyl groups or derivatives thereof by reactions involving amino or carboxyl groups, e.g. hydrolysis of esters or amides, by formation of halides, salts or esters
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C227/00—Preparation of compounds containing amino and carboxyl groups bound to the same carbon skeleton
- C07C227/38—Separation; Purification; Stabilisation; Use of additives
- C07C227/40—Separation; Purification
- C07C227/42—Crystallisation
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C227/00—Preparation of compounds containing amino and carboxyl groups bound to the same carbon skeleton
- C07C227/38—Separation; Purification; Stabilisation; Use of additives
- C07C227/44—Stabilisation; Use of additives
Abstract
The invention discloses a kind of 4-aminobenzoic acid ethyl ester raw powder's production technologies, have follow steps: 1. 4- nitrobenzoic acid obtains 4-aminobenzoic acid through catalytic hydrogenation；2. 4-aminobenzoic acid and ethyl alcohol obtain 4-aminobenzoic acid ethyl ester through esterification；3. 4-aminobenzoic acid ethyl ester obtains 4-aminobenzoic acid ethyl ester powder through ethyl alcohol recrystallization；The ethyl alcohol recrystallization is carried out in the presence of alkylsulfonate.The alkylsulfonates such as a small amount of dodecyl sodium sulfate are added in method of the invention during ethyl alcohol recrystallization, it can be good at adjusting the crystallization process of product in this way, so that product granularity is smaller and size distribution is uniform, product quality is high, can satisfy medicine, material and cosmetic industry to the high request of 4-aminobenzoic acid ethyl ester granularity.
Description
Technical field
The invention belongs to technical field of fine, and in particular to a kind of preparation side of 4-aminobenzoic acid ethyl ester powder
Method.
Background technique
4-aminobenzoic acid ethyl ester also known as benzocainum are mainly used in the production such as medicine, plastics and coating.In medicine
Aspect, 4-aminobenzoic acid ethyl ester are a kind of water-insoluble local anaesthetics, have analgesic, antipruritic effect well, are mainly used for bursting
Ulcer face, the surface of a wound and mucomembranous surface antalgesic-antipruritic, ointment can be used for the lubrications such as nasopharyngeal catheter, endoscope analgesic.As one kind
The strong local anaesthetics of ester dissolubility, 4-aminobenzoic acid ethyl ester are easily combined with the rouge layer of skin or mucous membrane, be not easily accessible generate in vivo it is malicious
Property.In terms of material, 4-aminobenzoic acid ethyl ester is the protective agent for covering solar UV, is made an addition in plastics and coating.
In order to effectively promote the dissolubility of 4-aminobenzoic acid ethyl ester, guarantee its dispersion effect in drug and material,
The curative effect and quality of product are improved, medicine, material and cosmetic industry propose the granularity of 4-aminobenzoic acid ethyl ester more next
Higher requirement, wherein the 4-aminobenzoic acid ethyl ester market demand of D90≤50 μm increases year by year.
Existing method is using the 4- aminobenzoic being mechanically pulverized or air-flow crushing obtains conventional production process
Acetoacetic ester crushes to obtain the 4-aminobenzoic acid ethyl ester of required granularity, this method for preparing powder be also easy to produce dust, production capacity it is low,
Energy consumption is big.Therefore, it is necessary to research and develop a kind of side of energy-efficient 4-aminobenzoic acid ethyl ester powder for preparing D90≤50 μm
Method.
Summary of the invention
The purpose of the present invention is to solve the above problem, provides a kind of 4- aminobenzoic of energy-efficient D90≤50 μm
Acetoacetic ester raw powder's production technology.
Realize the object of the invention technical solution be: a kind of 4-aminobenzoic acid ethyl ester raw powder's production technology, have with
Lower step:
1. 4- nitrobenzoic acid obtains 4-aminobenzoic acid through catalytic hydrogenation；
2. 4-aminobenzoic acid and ethyl alcohol obtain 4-aminobenzoic acid ethyl ester through esterification；
3. 4-aminobenzoic acid ethyl ester obtains 4-aminobenzoic acid ethyl ester powder through ethyl alcohol recrystallization；The ethyl alcohol weight
Crystallization is carried out in the presence of alkylsulfonate.
Above-mentioned steps 3. described in alkylsulfonate and step 2. described in the weight ratio of 4-aminobenzoic acid be
0.001: 1~0.01: 1.
Above-mentioned steps 3. described in alkylsulfonate be dodecyl sodium sulfate, myristyl sodium sulfonate, cetyl
One of sodium sulfonate, sodium stearyl sulfonate are a variety of；Preferably dodecyl sodium sulfate.
Above-mentioned steps 2. described in esterification be to be carried out under the catalysis of the concentrated sulfuric acid.
Above-mentioned steps 1. described in the catalyst that uses of catalytic hydrogenation for palladium-carbon catalyst or Raney's nickel.
In order to increase the dissolubility and reaction speed of product, saves and add alkali soluble solution and acid adding precipitation technique, reduce cost, subtract
Of low pollution, improves production efficiency, above-mentioned steps 1. described in catalytic hydrogenation further include using cocatalyst 4- dimethylamino
Pyridine；The 4-dimethylaminopyridine and the weight ratio of the 4- nitrobenzoic acid are 0.008: 1~0.08: 1.
The good effect that the present invention has:
(1) a small amount of [no more than the 1% of 4-aminobenzoic acid weight] is added in method of the invention during ethyl alcohol recrystallization
The alkylsulfonates such as dodecyl sodium sulfate can be good at the crystallization process for adjusting product, so that product granularity is smaller in this way
And size distribution is uniform, product quality is high, can satisfy medicine, material and cosmetic industry to 4-aminobenzoic acid ethyl ester granularity
High request.
(2) present invention is added a small amount of [no more than 4- nitrobenzoic acid weight in the catalytic hydrogenation of 4- nitrobenzoic acid
The 8% of amount] cocatalyst 4-dimethylaminopyridine, the dissolubility and reaction speed of product can be increased in this way, eliminate and add alkali
Dissolution and acid adding precipitation technique, reduce costs, reduce pollution, improve production efficiency.
(3) method of the invention is easy to operate, and production cost is low, and process safety is high, especially production capacity is high, low energy consumption,
Pollute it is small, it is energy-efficient.
Specific embodiment
(embodiment 1)
The 4-aminobenzoic acid ethyl ester raw powder's production technology of the present embodiment is as follows:
1. 4- nitrobenzoic acid 40g, water 200mL, 4-dimethylaminopyridine 0.5g and 3wt% are added into autoclave
Palladium carbon catalyst 0.6g first three times with nitrogen displacement then passes to hydrogen and pressure is adjusted to 0.8 ± 0.1MPa, while will be warm
At 100 ± 2 DEG C, heat-insulation pressure keeping is reacted to complete for degree control.
After reaction, catalyst is recovered by filtration, filtrate is cooling, it crystallizes, filtering, 80~85 DEG C of drying, obtain under vacuum
4-aminobenzoic acid 32.0g, yield 97.5%, fusing point are 187.0~187.5 DEG C, and content is 99.9%(dead-stop titration).
2. ethyl alcohol 200mL is first added into reaction flask and is kept for 25 ± 5 DEG C of temperature, the concentrated sulfuric acid of 98wt% is then added dropwise
27g is dripped off and is added 4-aminobenzoic acid 30g, is heated to reflux and fully reacting.
Recycling ethyl alcohol is concentrated under reduced pressure, residue is slowly added in the water that 120g temperature is 70 ± 2 DEG C, is added dropwise 30wt%'s
Sodium hydrate aqueous solution adjusts pH to 9~10, slowly decrease temperature crystalline, and filtering obtains 4-aminobenzoic acid ethyl ester.
3. ethyl alcohol 68mL is first added into refining reaction bottle, it is thick that 2. 4-aminobenzoic acid ethyl ester that step obtains then is added
Product and active carbon 0.5g, are warming up to reflux decoloration under stirring, dodecyl sodium sulfate 0.15g is added simultaneously into filtrate in filtering
Stirring, slowly crystallisation by cooling, filtering obtain 4-aminobenzoic acid ethyl ester white crystals powder 35.0g, yield 96.9%, fusing point is
88.7~90.3 DEG C, content is 100.2%(dead-stop titration).
Laser immunotherapy is used to detect its D90 as 45.8 μm.
(comparative example 1)
This comparative example the difference from embodiment 1 is that step 3.:
3. ethyl alcohol 68mL is first added into refining reaction bottle, it is thick that 2. 4-aminobenzoic acid ethyl ester that step obtains then is added
Product and active carbon 0.5g, are warming up to reflux decoloration under stirring, dodecyl sodium sulfate 1.5g is added into filtrate and stirs for filtering
It mixes, slowly crystallisation by cooling, filters, obtain 4-aminobenzoic acid ethyl ester white crystals powder 34.7g, yield 96.0%, fusing point is
88.3~89.9 DEG C, content is 99.7%(dead-stop titration).
Laser immunotherapy is used to detect its D90 as 151.8 μm.
(comparative example 2)
This comparative example the difference from embodiment 1 is that step 3.:
3. ethyl alcohol 68mL is first added into refining reaction bottle, it is thick that 2. 4-aminobenzoic acid ethyl ester that step obtains then is added
Product and active carbon 0.5g are warming up to reflux decoloration, filtering under stirring, filtrate is directly stirred, and slowly crystallisation by cooling, filtering obtain
4-aminobenzoic acid ethyl ester white crystals powder 34.2g, yield 94.7%, fusing point are 88.3~89.9 DEG C, content 99.5%
(dead-stop titration).
Laser immunotherapy is used to detect its D90 as 259.2 μm.
(comparative example 3)
This comparative example the difference from embodiment 1 is that step 1.:
1. 4- nitrobenzoic acid 40g, water 200ml is added to reaction flask, it is added dropwise at 35 ± 2 DEG C of temperature and stirring
The sodium hydrate aqueous solution of 30wt% adjusts pH to neutrality, keeps 4- nitrobenzoyl acid dissolution complete.
The palladium carbon catalyst 0.6g of above-mentioned material and 3wt% are added in autoclave, first three times with nitrogen displacement, then
It is passed through hydrogen and pressure is adjusted to 0.8 ± 0.1MPa, while temperature being controlled at 100 ± 2 DEG C, heat-insulation pressure keeping is reacted to complete.
After reaction, catalyst is recovered by filtration, filtrate is cooling, 25 ± 2 DEG C at a temperature of the hydrochloric acid of 30wt% is added dropwise
Adjusting pH to 3~4 crystallizes material, filters, and 80~85 DEG C of drying, obtain 4-aminobenzoic acid 29.4gg, yield is under vacuum
89.6%, fusing point is 186.8~187.5 DEG C, and content is 99.5%(dead-stop titration).
(embodiment 2)
The 4-aminobenzoic acid ethyl ester raw powder's production technology of the present embodiment is as follows:
1. 4- nitrobenzoic acid 60g, water 300mL, 4-dimethylaminopyridine 1.0g and 3wt% are added into autoclave
Palladium carbon catalyst 1.1g first three times with nitrogen displacement then passes to hydrogen and pressure is adjusted to 0.8 ± 0.1MPa, while will be warm
At 100 ± 2 DEG C, heat-insulation pressure keeping is reacted to complete for degree control.
After reaction, catalyst is recovered by filtration, filtrate is cooling, it crystallizes, filtering, 80~85 DEG C of drying, obtain under vacuum
4-aminobenzoic acid 47.7g, yield 96.9%, fusing point are 187.1~187.6 DEG C, and content is 100.2%(dead-stop titration).
2. ethyl alcohol 260mL is first added into reaction flask and is kept for 25 ± 5 DEG C of temperature, the concentrated sulfuric acid of 98wt% is then added dropwise
38g is dripped off and is added 4-aminobenzoic acid 45g, is heated to reflux and fully reacting.
Recycling ethyl alcohol is concentrated under reduced pressure, residue is slowly added in the water that 162g temperature is 70 ± 2 DEG C, is added dropwise 25wt%'s
Sodium hydrate aqueous solution adjusts pH to 9~10, slowly decrease temperature crystalline, and filtering obtains 4-aminobenzoic acid ethyl ester.
3. ethyl alcohol 90mL is first added into refining reaction bottle, it is thick that 2. 4-aminobenzoic acid ethyl ester that step obtains then is added
Product and active carbon 0.8g, are warming up to reflux decoloration under stirring, myristyl sodium sulfonate 0.21g is added simultaneously into filtrate in filtering
Stirring, slowly crystallisation by cooling, filtering obtain 4-aminobenzoic acid ethyl ester white crystals powder 53.1g, yield 98.0%, fusing point is
88.8~90.5 DEG C, content is 100.3%(dead-stop titration).
Laser immunotherapy is used to detect its D90 as 46.7 μm.
(embodiment 3)
The 4-aminobenzoic acid ethyl ester raw powder's production technology of the present embodiment is as follows:
1. 4- nitrobenzoic acid 60g, water 300mL, 4-dimethylaminopyridine 1.0g and 3wt% are added into autoclave
Palladium carbon catalyst 1.1g first three times with nitrogen displacement then passes to hydrogen and pressure is adjusted to 0.8 ± 0.1MPa, while will be warm
At 100 ± 2 DEG C, heat-insulation pressure keeping is reacted to complete for degree control.
After reaction, catalyst is recovered by filtration, filtrate is cooling, it crystallizes, filtering, 80~85 DEG C of drying, obtain under vacuum
4-aminobenzoic acid 47.7g, yield 96.9%, fusing point are 186.9~187.5 DEG C, and content is 99.8%(dead-stop titration).
2. elder generation ethyl alcohol 260mL is added into reaction flask and is kept for 25 ± 5 DEG C of temperature, the concentrated sulfuric acid of 98wt% is then added dropwise
38g is dripped off and is added 4-aminobenzoic acid 45g, is heated to reflux and fully reacting.
Recycling ethyl alcohol is concentrated under reduced pressure, residue is slowly added in the water that 162g temperature is 70 ± 2 DEG C, is added dropwise 25wt%'s
Sodium hydrate aqueous solution adjusts pH to 9~10, slowly decrease temperature crystalline, and filtering obtains 4-aminobenzoic acid ethyl ester.
3. ethyl alcohol 90mL is first added into refining reaction bottle, it is thick that 2. 4-aminobenzoic acid ethyl ester that step obtains then is added
Product and active carbon 0.8g, are warming up to reflux decoloration under stirring, sodium cetanesulfonate 0.21g is added simultaneously into filtrate in filtering
Stirring, slowly crystallisation by cooling, filtering obtain 4-aminobenzoic acid ethyl ester white crystals powder 53.1g, yield 98.0%, fusing point is
88.5~90.1 DEG C, content is 100.1%(dead-stop titration).
Laser immunotherapy is used to detect its D90 as 47.1 μm.
(embodiment 4)
The 4-aminobenzoic acid ethyl ester raw powder's production technology of the present embodiment is as follows:
1. 4- nitrobenzoic acid 300g, water 1500mL, 4-dimethylaminopyridine 3.0g and 3wt% are added into autoclave
Palladium carbon catalyst 5.0g, first with nitrogen displacement three times, then pass to hydrogen and pressure be adjusted to 0.8 ± 0.1MPa, simultaneously will
Temperature is controlled at 100 ± 2 DEG C, and heat-insulation pressure keeping is reacted to complete.
After reaction, catalyst is recovered by filtration, filtrate is cooling, it crystallizes, filtering, 80~85 DEG C of drying, obtain under vacuum
4-aminobenzoic acid 241.3g, yield 98.0%, fusing point are 187.2~187.7 DEG C, and content is 100.3%(dead-stop titration).
2. ethyl alcohol 1380mL is first added into reaction flask and is kept for 25 ± 5 DEG C of temperature, the concentrated sulfuric acid of 98wt% is then added dropwise
188g is dripped off and is added 4-aminobenzoic acid 225g, is heated to reflux and fully reacting.
Recycling ethyl alcohol is concentrated under reduced pressure, residue is slowly added in the water that 800g temperature is 70 ± 2 DEG C, is added dropwise 25wt%'s
Sodium hydrate aqueous solution adjusts pH to 9~10, slowly decrease temperature crystalline, and filtering obtains 4-aminobenzoic acid ethyl ester.
3. ethyl alcohol 450mL is first added into refining reaction bottle, 2. 4-aminobenzoic acid ethyl ester that step obtains then is added
Crude product and active carbon 4.0g, are warming up to reflux decoloration under stirring, dodecyl sodium sulfate 1.0g is added simultaneously into filtrate in filtering
Stirring, slowly crystallisation by cooling, filtering obtain 4-aminobenzoic acid ethyl ester white crystals powder 265.5g, yield 98.0%, fusing point
It is 88.8~90.6 DEG C, content is 100.3%(dead-stop titration).
Laser immunotherapy is used to detect its D90 as 46.2 μm.
(embodiment 5)
The 4-aminobenzoic acid ethyl ester raw powder's production technology of the present embodiment is as follows:
1. 4- nitrobenzoic acid 300g, water 1500mL, 4-dimethylaminopyridine 3.5g and 3wt% are added into autoclave
Raney's nickel catalyst 10.6g, first with nitrogen displacement three times, then pass to hydrogen and pressure be adjusted to 0.8 ± 0.1MPa, simultaneously
Temperature is controlled at 100 ± 2 DEG C, heat-insulation pressure keeping is reacted to complete.
After reaction, catalyst is recovered by filtration, filtrate is cooling, it crystallizes, filtering, 82~88 DEG C of drying, obtain under vacuum
4-aminobenzoic acid 241.9g, yield 98.3%, fusing point are 187.1~187.6 DEG C, and content is 100.2%(dead-stop titration).
2. ethyl alcohol 1380mL is first added into reaction flask and is kept for 25 ± 5 DEG C of temperature, the concentrated sulfuric acid of 97wt% is then added dropwise
180g is dripped off and is added 4-aminobenzoic acid 225g, is heated to reflux and fully reacting.
Recycling ethyl alcohol is concentrated under reduced pressure, residue is slowly added in the water that 800g temperature is 70 ± 2 DEG C, is added dropwise 30wt%'s
Sodium hydrate aqueous solution adjusts pH to 9~10, slowly decrease temperature crystalline, and filtering obtains 4-aminobenzoic acid ethyl ester.
3. ethyl alcohol 450mL is first added into refining reaction bottle, 2. 4-aminobenzoic acid ethyl ester that step obtains then is added
Crude product and active carbon 5.0g, are warming up to reflux decoloration under stirring, dodecyl sodium sulfate 1.1g is added simultaneously into filtrate in filtering
Stirring, slowly crystallisation by cooling, filtering obtain 4-aminobenzoic acid ethyl ester white crystals powder 264.3g, yield 97.5%, fusing point
It is 88.9~90.3 DEG C, content is 100.5%(dead-stop titration).
Laser immunotherapy is used to detect its D90 as 46.0 μm.
Claims (4)
1. a kind of 4-aminobenzoic acid ethyl ester raw powder's production technology, it is characterised in that have follow steps:
1. 4- nitrobenzoic acid obtains 4-aminobenzoic acid through catalytic hydrogenation；
2. 4-aminobenzoic acid and ethyl alcohol obtain 4-aminobenzoic acid ethyl ester through esterification；
3. 4-aminobenzoic acid ethyl ester obtains 4-aminobenzoic acid ethyl ester powder through ethyl alcohol recrystallization；The ethyl alcohol recrystallization
It is to be carried out in the presence of alkylsulfonate；The alkylsulfonate and step 2. described in 4-aminobenzoic acid weight
Amount is than being 0.001: 1~0.01: 1；The alkylsulfonate is dodecyl sodium sulfate.
2. 4-aminobenzoic acid ethyl ester raw powder's production technology according to claim 1, it is characterised in that: above-mentioned steps are 2.
Described in esterification be to be carried out under the catalysis of the concentrated sulfuric acid.
3. 4-aminobenzoic acid ethyl ester raw powder's production technology according to claim 1, it is characterised in that: above-mentioned steps are 1.
Described in the catalyst that uses of catalytic hydrogenation for palladium-carbon catalyst or Raney's nickel.
4. 4-aminobenzoic acid ethyl ester raw powder's production technology according to claim 1 or 3, it is characterised in that: above-mentioned step
Suddenly 1. described in catalytic hydrogenation further include using cocatalyst 4-dimethylaminopyridine；The 4-dimethylaminopyridine and institute
The weight ratio for stating 4- nitrobenzoic acid is 0.008: 1~0.08: 1.
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| CN111732521B (en) * | 2020-06-16 | 2021-04-20 | 浙江优创材料科技股份有限公司 | Preparation method of ethyl p-aminobenzoate |
| CN114394909A (en) * | 2021-12-31 | 2022-04-26 | 大连新阳光材料科技有限公司 | Preparation method of p-aminobenzoic acid micro powder |
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