CN106966894B - A kind of method of the pipe type continuously production chloro- 5- fluorobenzoyl chloride of 2,4- bis- - Google Patents
A kind of method of the pipe type continuously production chloro- 5- fluorobenzoyl chloride of 2,4- bis- Download PDFInfo
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- CN106966894B CN106966894B CN201710077693.8A CN201710077693A CN106966894B CN 106966894 B CN106966894 B CN 106966894B CN 201710077693 A CN201710077693 A CN 201710077693A CN 106966894 B CN106966894 B CN 106966894B
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/58—Preparation of carboxylic acid halides
- C07C51/60—Preparation of carboxylic acid halides by conversion of carboxylic acids or their anhydrides or esters, lactones, salts into halides with the same carboxylic acid part
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/16—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation
- C07C51/21—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen
- C07C51/255—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation with molecular oxygen of compounds containing six-membered aromatic rings without ring-splitting
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Abstract
The present invention provides a kind of pipe type continuously productions 2; the preparation method of the chloro- 5- fluorobenzoyl chloride of 4- bis-; with 2; the chloro- 5- fluoro acetophenone of 4- bis- is starting material; under the catalysis of nitration mixture system, through dioxygen oxidation at the chloro- 5- fluobenzoic acid of 2,4- bis-; again through the acylated obtained final product 2 of bis- (trichloromethyl) carbonic esters (BTC), the chloro- 5- fluorobenzoyl chloride of 4- bis-.The present invention uses serialization tubular reactor; online reaction mass is few; be conducive to DCS control; nitric acid is few as catalyst usage amount and recycled; oxygen participates in reacting as oxidant; bis- (trichloromethyl) carbonic esters, that is, BTC substitution thionyl chloride is as acylating reagent, and not only save the cost, avoids the discharge of the pernicious gases such as nitrogen oxides and sulfur dioxide.
Description
Technical field
The invention belongs to chemical intermediate preparation method technical fields, and in particular to the chloro- 5- fluorobenzene of 2,4- of one kind bis-
The preparation method of formyl chloride.
Background technique
2,4- bis- chloro- 5- fluorobenzoyl chlorides (No. CAS: 86393-34-2) are a kind of important shown in structure such as formula (I)
Chemical intermediate, 2,4- bis- chloro- 5- fluorobenzoyl chlorides are to prepare Comprecin Ciprofloxacin, Enrofloxacin, double
The important intermediate of Flucloxacillin, Temafloxacin etc. is also used for antipsychotic specific drug psychoperidol, trifluperidol, five fluorine
The primary raw material of benefit, quinolones (such as Ciprofloxacin) drug；It is also used to agricultural chemical insecticide and ovoinhibitor and plastics, tree
The identification of rouge.Since the chloro- 5- fluorobenzoyl chloride of 2,4- bis- is the substitute products of the chloro- 5- fluoro acetophenone of 2,4- bis-, demand is increasingly
Increase and has developed a variety of synthetic routes.
The preparation method of the disclosed related chloro- 5- fluorobenzoyl chloride of 2,4- bis- both at home and abroad, mainly include the following types:
The chloro- 5- fluorobenzoyl of 2,4- bis- is made through friedel-crafts acylation, oxidation, acylation reaction using 2,4 dichloro fluorobenzene as raw material
Chlorine.1, such as Chinese Medicine magazine, 1991,22 (12), 551 and Chinese antibiotic magazine, 2004,29 (9), 529 etc. report with
2,4 dichloro fluorobenzene is in AlCl3Under catalysis, the chloro- 5- fluoro acetophenone of 2,4- bis- is made with excess acetyl chloride, then through sodium hypochlorite oxygen
Change, the chloro- 5- fluorobenzoyl chloride of 2,4- bis- is made in thionyl chloride chloride；2, such as advanced chemical engineering journal, 2005,19 (5),
708 and Chemical Engineer, 2007,141 (6), 48 etc., which report nitric acid, carries out oxidation reaction instead of sodium hypochlorite；3, such as
US5481032, which is reported, carries out oxidation reaction with the concentrated sulfuric acid and hydrogen peroxide；4, such as CN1091418 and organic silicon-fluorine consulting, 2005,
(3), it 41 etc. reports with chloracetyl chloride progress acylation reaction；Existing technique as above there are process routes longer, severe toxicity chemistry
The use of product, the reaction time is long, and online volume is bigger, it is difficult to realize DCS control, the problems such as production capacity is relatively high, yield
Realize that industrialization difficulty is larger.
Summary of the invention
The present invention provides a kind of preparation methods of pipe type continuously production chloro- 5- fluorobenzoyl chloride of 2,4- bis-, solve such as
The technical issues of bis- chloro- 5- fluorobenzoyl chloride of production 2,4- of what simple and effective.
A kind of method of the pipe type continuously production chloro- 5- fluorobenzoyl chloride of 2,4- bis-, which is characterized in that the production method
It is with the chloro- 5- fluoro acetophenone of 2,4- bis- shown in formula (II) for starting material, under the catalysis of nitration mixture system, warp
The chloro- 5- fluobenzoic acid of 2,4- bis- shown in a dioxygen oxidation accepted way of doing sth (III), then be made through bis- (trichloromethyl) carbonic esters (BTC) are acylated
The chloro- 5- fluorobenzoyl chloride of 2,4- bis- shown in final product formula (I)；
Specific reaction equation is as follows:
Preferably, specifically comprising the following steps:
(1) tubular reactor is added in the chloro- 5- fluoro acetophenone of 2,4- bis-, nitration mixture system and carries out tubular type oxygen
Change the reaction preparation chloro- 5- fluobenzoic acid (III) of 2,4- bis-；The temperature of tubular type oxidation reaction is 20~70 DEG C；Residence time be 5~
10min；Wherein the molar feed ratio of the chloro- 5- fluoro acetophenone (II) of 2,4- bis- and nitric acid is 1:10%~100%；Pipe reaction
1~15m of length of device, 1~5mm of pipe diameter.
(2) the chloro- 5- fluobenzoic acid (III) of 2,4- bis- is dissolved in the toluene of heat, pipe is added in the toluene solution of itself and BTC
Tubular type acylation reaction is carried out in formula reactor；Wherein the molar feed ratio of the chloro- 5- fluobenzoic acid (III) of 2,4- bis- and BTC are 1:1
~1.2；The temperature of tubular type acylation reaction is 80~110 DEG C；Reaction time is 8~30min；The length 10 of tubular reactor~
50m, 1~5mm of pipe diameter.
Preferably, the oxygen of oxidation reaction described in step (1) is industrial oxygen, the oxygen for squeezing into tubular reactor is
2~3 times for squeezing into the amount of the substance of the chloro- 5- fluoro acetophenone of 2,4- bis- simultaneously.
Preferably, nitric acid described in step (1) is industrial nitric acid, nitric acid squeezes into tubular reactor as catalyst
Nitric acid is while squeezing into 0.5~1 times of amount of substance of the chloro- 5- fluoro acetophenone of 2,4- bis- in nitration mixture.
Preferably, the industrial sulphuric acid that sulfuric acid described in step (1) is 50%, sulfuric acid is as catalyst, in mixed acid system
The dosage of sulfuric acid is 1~2 times of nitric acid quality.
Preferably, the amount of the substance of BTC described in step (2) is the amount of the substance of the chloro- 5- fluobenzoic acid of 2,4- bis-
0.4~0.5 times.
Preferably, using the method for side border ring distillation in step (2), in time by toluene and excessive BTC from system
In isolate, the organic phase in collector is finally carried out vacuum distillation collection into above-mentioned BTC system by recycled
35mmHg, 143~144 DEG C of fractions are final products 2, the chloro- 5- fluorobenzoyl chloride of 4- bis-.
Compared with the existing technology, its advantages are embodied in the present invention:
(1) present invention is online anti-using progress tubular type oxidation reaction and tubular type acylation reaction in serialization tubular reactor
It answers material few, and the discharge of pollutant can be effectively reduced with recycled, simplify operation, be conducive to DCS control, have
Conducive to industrialization large-scale production；
(2) using the oxygen in air as oxidant, nitration mixture system is not only inexpensive easy as catalyst
, reduce the discharge of exhaust gas, reduces pollution, it is environmental-friendly, improve the competitiveness of product in market；
(3) respectively step reaction is common reaction involved in synthetic route, and operating condition is stablized, and post-processes simple side
Just, product purity is higher, and condition is preferable, and yield is preferable；
(4) the pipe type continuously production method is raw material using the chloro- 5- fluoro acetophenone of 2,4- bis-, using oxygen as oxidant,
Nitration mixture is catalyst, and bis- (trichloromethyl) carbonic esters, that is, BTC substitution thionyl chloride is as acylating reagent, continuously
Metaplasia produce, have it is easy to operate, the reaction time is short, product yield high, and online reaction mass is few, it is easy to accomplish DCS control, cost
The dosage of lower and advantages of environment protection, nitration mixture greatly reduces, and has saved resource, avoids nitrogen oxides and sulfur dioxide etc.
The discharge of pernicious gas protects environment, and condition is preferable, and product purity is higher, and yield is higher, industrialization valence with higher
Value.
Detailed description of the invention
Fig. 1 is the production procedure schematic diagram that pipe type continuously provided by the invention produces the chloro- 5- fluorobenzoyl chloride of 2,4- bis-.
Specific embodiment
The invention will be further described below, but technical parameter involved in scheme cannot be interpreted as to the present invention
Limitation.
The preparation of the chloro- 5- fluobenzoic acid of embodiment one: 2,4- bis-
Reaction unit such as Fig. 1, the first tubular reactor: single tube, length 5m, pipe diameter 5mm；The oxidation of step 1 tubular type is anti-
Answer: the chloro- 5- fluoro acetophenone of 2,4- bis- that 2.00Kg is added into liquid storage device A is spare；Then it is added 0.30Kg's into liquid storage device B
50% sulfuric acid of 60% concentrated nitric acid and 0.50Kg are spare；D is oxygen bottle.
The valve of liquid storage device A, B and D are opened, controls the molar flow of A, B, D than being beaten with the ratio of 1:0.3:3 by metering pump
Enter pipe reaction system, control tubular reactor temperature is 50 DEG C, in the connection of tubular reactor end collector C, collector C
Product is filtered, and the chloro- 5- fluobenzoic acid crude product 2.01Kg of 2,4- bis- is obtained, and water phase is pumped into liquid storage device B.
The preparation of the chloro- 5- fluobenzoic acid of embodiment two: 2,4- bis-
All steps are the same as example 1 in the present embodiment, and difference is the length 5m of tubular reactor, pipe diameter
1mm obtains the chloro- 5- fluobenzoic acid 1.82Kg of 2,4- bis-.
The preparation of the chloro- 5- fluobenzoic acid of embodiment three: 2,4- bis-
All steps are the same as example 1 in the present embodiment, and difference is the length 1m of tubular reactor, pipe diameter
5mm obtains the chloro- 5- fluobenzoic acid 0.81Kg of 2,4- bis-.
Example IV: the preparation of the chloro- 5- fluobenzoic acid of 2,4- bis-
All steps are the same as example 1 in the present embodiment, and difference is the length 3m of tubular reactor, pipe diameter
5mm obtains the chloro- 5- fluobenzoic acid 1.83Kg of 2,4- bis-.
The preparation of the chloro- 5- fluorobenzoyl chloride of embodiment five: 2,4- bis-
Reaction unit such as Fig. 1, the second tubular reactor: single tube, length 10m, pipe diameter 5mm；Step 2 tubular type is acylated
Reaction: putting into the chloro- 5- fluobenzoic acid 2.00Kg of 2,4- bis- into liquid storage device E, and the toluene of 2.00Kg, heating stirring is then added
It dissolves spare；Then then the toluene of 1.00Kg is added in bis- (trichloromethyl) carbonic esters that 0.90Kg is put into liquid storage device F, stir
It is spare to mix dissolution.
The valve of liquid storage device E and F are opened, controls molar flow than squeezing into pipe reaction by metering pump with the ratio of 1:1.2
System, control tubular reactor temperature are 110 DEG C, and tubular reactor end connects collector G, and collector G air-distillation will be molten
Agent toluene and excessive bis- (trichloromethyl) carbonic esters steam, then condensing recovery to bis- (trichloromethyl) carbonic ester toluene recoveries
Device H, collector G obtain the chloro- 5- fluorobenzoyl chloride crude product of 2,4- bis-, and 35mmHg is collected in rectifying, and 143~144 DEG C of fractions obtain finally
Product 2, the chloro- 5- fluorobenzoyl chloride 2.15Kg of 4- bis-, total recovery 99.1%.
The preparation of the chloro- 5- fluorobenzoyl chloride of embodiment six: 2,4- bis-
All steps are identical as embodiment five in the present embodiment, and difference is the length 10m of tubular reactor, pipe diameter
1mm obtains the chloro- 5- fluorobenzoyl chloride 1.86Kg of 2,4- bis-
The preparation of the chloro- 5- fluorobenzoyl chloride of embodiment seven: 2,4- bis-
All steps are identical as embodiment five in the present embodiment, and difference is the length 1m of tubular reactor, pipe diameter
5mm obtains the chloro- 5- fluorobenzoyl chloride 0.32Kg of 2,4- bis-
The preparation of the chloro- 5- fluorobenzoyl chloride of embodiment eight: 2,4- bis-
All steps are identical as embodiment five in the present embodiment, and difference is the length 5m of tubular reactor, pipe diameter
5mm obtains the chloro- 5- fluorobenzoyl chloride 1.24Kg of 2,4- bis-
The preferred embodiments of the invention are only listed above, and protection scope of the present invention is not restricted to this, this field
Made any change is each fallen in the scope of the present invention technical staff within the scope of the invention as claimed.
Claims (7)
1. a kind of method of the pipe type continuously production chloro- 5- fluorobenzoyl chloride of 2,4- bis-, which is characterized in that the production method is
With the chloro- 5- fluoro acetophenone of 2,4- bis- shown in formula (II) for starting material, under the catalysis of nitration mixture system, through oxygen
Gas aoxidizes the chloro- 5- fluobenzoic acid of 2,4- bis- shown in an accepted way of doing sth (III), then through bis- (trichloromethyl) carbonic esters (BTC) in solvent first
The chloro- 5- fluorobenzoyl chloride of 2,4- bis- shown in acylated obtained final product formula (I) in benzene；
Specific reaction equation is as follows:
。
2. the method for the pipe type continuously production chloro- 5- fluorobenzoyl chloride of 2,4- bis- according to claim 1, feature exist
In specifically comprising the following steps:
(1) tubular reactor is added in the chloro- 5- fluoro acetophenone of 2,4- bis-, nitration mixture system and carries out tubular type oxidation instead
The chloro- 5- fluobenzoic acid (III) of 2,4- bis- should be prepared；The temperature of tubular type oxidation reaction is 20~70 DEG C；Residence time be 5~
10min；Wherein the molar feed ratio of the chloro- 5- fluoro acetophenone (II) of 2,4- bis- and nitric acid is 1: 10%~100%；Tubular reactor
1~15m of length, 1~5mm of pipe diameter；
(2) the chloro- 5- fluobenzoic acid (III) of 2,4- bis- is dissolved in the toluene of heat, it is anti-that tubular type is added in the toluene solution of itself and BTC
Answer progress tubular type acylation reaction in device；Wherein the molar feed ratio of the chloro- 5- fluobenzoic acid (III) of 2,4- bis- and BTC be 1: 1~
1.2；The temperature of tubular type acylation reaction is 80~110 DEG C；Reaction time is 8~30min；10~50m of length of tubular reactor,
1~5mm of pipe diameter.
3. the method for the pipe type continuously production chloro- 5- fluorobenzoyl chloride of 2,4- bis- according to claim 1, feature exist
In the oxygen is industrial oxygen, and the oxygen for squeezing into tubular reactor is while squeezing into the substance of the chloro- 5- fluoro acetophenone of 2,4- bis-
2~3 times of amount.
4. the method for the pipe type continuously production chloro- 5- fluorobenzoyl chloride of 2,4- bis- according to claim 2, feature exist
In nitric acid described in step (1) is industrial nitric acid, nitric acid and sulfuric acid as catalyst, squeezes into nitre in the nitration mixture of tubular reactor
0.5~1 times of the amount of the sour substance for being while squeezing into the chloro- 5- fluoro acetophenone of 2,4- bis-.
5. the method for the pipe type continuously production chloro- 5- fluorobenzoyl chloride of 2,4- bis- according to claim 2, feature exist
The industrial sulphuric acid for being 50% in, sulfuric acid described in step (1), nitric acid and sulfuric acid are as catalyst, the use of sulfuric acid in mixed acid system
Amount is 1~2 times of nitric acid quality.
6. the method for the pipe type continuously production chloro- 5- fluorobenzoyl chloride of 2,4- bis- according to claim 2, feature exist
In the amount of the substance of BTC described in step (2) is 0.4~0.5 times of the amount of the substance of the chloro- 5- fluobenzoic acid of 2,4- bis-.
7. the method for the pipe type continuously production chloro- 5- fluorobenzoyl chloride of 2,4- bis- according to claim 2, feature exist
In the method distilled in step (2) using side border ring is in time isolated toluene and excessive BTC, circulating sleeve from system
It uses in above-mentioned BTC system, the organic phase in collector is finally subjected to vacuum distillation and collects 35mmHg, 143~144 DEG C evaporate
Divide is final products 2, the chloro- 5- fluorobenzoyl chloride of 4- bis-.
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| CN109721504B (en) * | 2019-01-29 | 2022-03-11 | 浙江工业大学 | Method for continuously preparing amide from carboxylic acid |
| CN112142577B (en) * | 2020-09-23 | 2022-04-29 | 浙江工业大学 | Metal-free catalytic oxidation system, oxygen oxidation method and production method applied to benzoic acid derivative |
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|---|---|---|---|---|
| US5481032A (en) * | 1992-11-29 | 1996-01-02 | Hoechst Aktiengesellschaft | Process for the preparation of halogenated benzoic acids |
| CN101033198A (en) * | 2007-02-14 | 2007-09-12 | 浙江工业大学 | Compound of N-substituted-2,4-dichloro-5-fluorobenzamide, preparation and application thereof |
| CN104211590A (en) * | 2014-09-16 | 2014-12-17 | 浙江先锋科技股份有限公司 | Preparation method of 2, 4-dichloro-fluorobenzoyl chloride |
-
2017
- 2017-02-13 CN CN201710077693.8A patent/CN106966894B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5481032A (en) * | 1992-11-29 | 1996-01-02 | Hoechst Aktiengesellschaft | Process for the preparation of halogenated benzoic acids |
| CN101033198A (en) * | 2007-02-14 | 2007-09-12 | 浙江工业大学 | Compound of N-substituted-2,4-dichloro-5-fluorobenzamide, preparation and application thereof |
| CN104211590A (en) * | 2014-09-16 | 2014-12-17 | 浙江先锋科技股份有限公司 | Preparation method of 2, 4-dichloro-fluorobenzoyl chloride |
Non-Patent Citations (2)
| Title |
|---|
| 《2,4-二氯-5-氟苯甲酸的合成》;张跃臻,于会军;《辽宁化工》;19931231(第6期);37-38 * |
| 2,4-二氯-5-氟苯甲酸的新合成法;王树良，戴桂元;《中国医药工业杂志》;19961231;第27卷(第2期);83-84 * |
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