CN108947823A - A kind of preparation method of benzene oxycarboxylic acid ester - Google Patents

A kind of preparation method of benzene oxycarboxylic acid ester Download PDF

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Publication number
CN108947823A
CN108947823A CN201810225329.6A CN201810225329A CN108947823A CN 108947823 A CN108947823 A CN 108947823A CN 201810225329 A CN201810225329 A CN 201810225329A CN 108947823 A CN108947823 A CN 108947823A
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China
Prior art keywords
preparation
salt
chlorate
solvent
acid ester
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CN201810225329.6A
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Chinese (zh)
Inventor
孙国庆
侯永生
迟志龙
贺恩静
胡义山
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Shandong Runbo Biological Technology Co Ltd
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Shandong Runbo Biological Technology Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C37/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
    • C07C37/64—Preparation of O-metal compounds with O-metal group bound to a carbon atom belonging to a six-membered aromatic ring
    • C07C37/66—Preparation of O-metal compounds with O-metal group bound to a carbon atom belonging to a six-membered aromatic ring by conversion of hydroxy groups to O-metal groups
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C67/00—Preparation of carboxylic acid esters
    • C07C67/30—Preparation of carboxylic acid esters by modifying the acid moiety of the ester, such modification not being an introduction of an ester group
    • C07C67/31—Preparation of carboxylic acid esters by modifying the acid moiety of the ester, such modification not being an introduction of an ester group by introduction of functional groups containing oxygen only in singly bound form
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C67/00—Preparation of carboxylic acid esters
    • C07C67/48—Separation; Purification; Stabilisation; Use of additives
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C67/00—Preparation of carboxylic acid esters
    • C07C67/48—Separation; Purification; Stabilisation; Use of additives
    • C07C67/52—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation

Abstract

The present invention provides a kind of preparation methods of benzene oxycarboxylic acid ester, comprising the following steps: A) phenolic compound and alkaline hydrated oxide be dehydrated into salt in organic solvent, obtain the salt of phenolic compound；B) after at salt, chlorine carboxylate is added, carries out condensation reaction, obtains the mixed solution of benzene oxycarboxylic acid ester and chlorate；C system temperature) is down to by 37-42 DEG C, and ultrasound with the speed of 1-5 DEG C/min, so that chlorate crystal grain is become larger, is filtered to remove chlorate；The organic solvent is any two kinds of mixture in toluene, dimethylbenzene, chlorobenzene, phenol, butanol and isobutanol.What the present invention carried out phenol in mixed organic solvents is dehydrated into salt, and system remains uniform state in dehydration, realizes continuous production, and dehydration efficiency is higher, and entire production process efficiency is higher.And raw material is easy to get, with short production cycle, energy consumption is lower, lower production costs.And it is filtered to remove the chlorate of generation, realize waste water zero generates zero-emission.

Description

A kind of preparation method of benzene oxycarboxylic acid ester
Technical field
The present invention relates to herbicide preparation technical field more particularly to a kind of preparation methods of benzene oxycarboxylic acid ester.
Background technique
Benzene oxycarboxylic acid ester herbicide is the hormone-type selective herbicide of first kind merchandized handling in the world, to environment Close friend has the characteristics that residual life is short and less toxic to people and other biological, seldom generates drug resistance, be mainly used for corn, wheat Prevent and kill off broadleaf weed, nutgrass flatsedge and certain malignant weeds in equal gramineous crops field.In benzene oxycarboxylic acid ester herbicide using compared with To be widely chloro phenoxy acetic acid ester series.Wherein being most widely used with 2,4 dichlorophenoxyacetic acid ester.
Currently, the preparation method of 2,4- dichlorphenoxyacetic acid esters mainly includes following two step:
1) using phenol as primary raw material, 2,4- chlorophenesic acid is made through chlorination；
2) 2,4- chlorophenesic acid is condensed with monoxone under alkaline condition, and reaction solution is acidified, 2,4- bis- is obtained by filtration Chlorophenoxyacetic acid wet feed obtains 2,4- dichlorphenoxyacetic acid after drying；
3) esterification is carried out in the presence of a catalyst, obtains 2,4- for raw material with 2,4- dichlorphenoxyacetic acid, alcohol Dichlorphenoxyacetic acid ester.
In above-mentioned preparation method, intermediate product 2,4- chlorophenesic acid are generated, this product has the penetrating odor of extremely difficult news, Cause production on-site environment very poor, and chlorination is selectively poor causes its purity lower.
During step 2) condensation, it is intermolecular that impurity chlorophenesic acid and polystream phenol in chlorophenol can occur two Condensation, generate severe toxicity, series compound --- dioxin difficult to degrade, and then generate and largely contain chlorinated phenol, chlorobenzene The dangerous waste of fluoroacetic acid, and also contain dioxin in output product, this brings greatly to the health of environment and producers The use of risk, the product that dioxin can also be prepared with step 3) enters plant, air, soil and water source, and with food The enrichment of object chain, in turn results in more serious environmental hazard.
Meanwhile above-mentioned reaction route chlorination poor selectivity, aftertreatment technology have loss of effective components, the yield of product is inclined It is low, and understand the output largely waste water containing hydroxyacetic acid and abraum salt, and largely contain chlorophenol, chloro phenoxy acetic acid Dangerous waste, three-protection design pressure is big, processing cost is high.
Williamson condensation method disclosed in the prior art, production technology are: phenol in water phase at salt, then again and chlorine Acetic acid neutralization with alkali carries out Williamson condensation reaction at the product of salt in water phase, obtains phenoxy acetate, then sour again Change, obtain phenoxy acetic acid, after filtering drying again with corresponding alcohol esterification, last chlorination.Since reaction is carried out in water phase, deposit The problems such as monoxone consumes height, and waste water abraum salt amount is big.
Therefore, it is extremely urgent to develop a kind of advanced synthesis technology.
Summary of the invention
In view of this, having the technical problem to be solved in the present invention is that providing a kind of preparation method of benzene oxycarboxylic acid ester Higher production efficiency, and complete non-wastewater discharge.
In order to solve the above technical problems, the present invention provides a kind of preparation methods of benzene oxycarboxylic acid ester, comprising the following steps:
A) phenolic compound and alkaline hydrated oxide are dehydrated into salt in organic solvent, obtain the salt of phenolic compound；
B) after at salt, chlorine carboxylate is added, carries out condensation reaction, obtains the mixed solution of benzene oxycarboxylic acid ester and chlorate；
C system temperature) is down to by 37-42 DEG C, and ultrasound with the speed of 1-5 DEG C/min, chlorate crystal grain is made to become larger, is filtered Remove chlorate；
The organic solvent is any two kinds of mixture in toluene, dimethylbenzene, chlorobenzene, phenol, butanol and isobutanol.
Reaction equation of the invention is as follows:
Wherein, the R is H or methyl.
M is Na, K, Ca, Mg or Al.
R1The preferably alkylidene of C1~C5；The more preferably alkylidene of C1~C4, further, preferably methylene (- CH2), methylmethylene (- CH (CH3) -), ethylidene (- CH2-CH2), propylidene (- CH2-CH2-CH2) or butylidene (- (CH2)4-)。
R2The preferably naphthenic base of the alkyl of C1~C10 or C3~C10；More preferably methyl, ethyl, propyl, isopropyl, Butyl, isobutyl group, butyl, isobutyl group, cyclopropyl or cyclohexyl.
The phenolic compound is preferably phenol or o-cresol.
The alkaline hydrated oxide is preferably sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide or aluminium hydroxide； More preferably sodium hydroxide, potassium hydroxide or calcium hydroxide.
The alkali compounds can add in form of an aqueous solutions, can also add in solid form, preferred mass is dense The aqueous solution of 30% or more degree.
The dosage of the phenolic compound and alkaline hydrated oxide compares according to metering, preferred molar ratio 1:1.
The present invention by phenolic compound and alkaline hydrated oxide in organic solvent Direct Dehydration at salt, the organic solvent Other than carrying out the effect of dispersing and dissolving to phenates, also has the function of dehydration.
Currently preferred, the organic solvent is any in toluene, dimethylbenzene, chlorobenzene, phenol, butanol and isobutanol Two kinds of mixture.
The mass ratio of the phenolic compound and organic solvent is preferably 1:(2~20), more preferably 1:(2~18).
It is furthermore preferred that the organic solvent is made of solvent A and solvent B, the solvent A is selected from toluene, dimethylbenzene and chlorine Any one in benzene, any one of the solvent B in butanol and isobutanol.
The mass ratio of the solvent A and solvent B are preferably (2~4): 1.
The present invention uses specific mixed solvent, solves single solvent during the dehydration process, has what is largely salted out to ask Topic, avoids the risk of explosion, so that system remains uniform state during dehydrating condensation, realizes continuous production, And dehydration efficiency is higher.
The temperature for being dehydrated into salt is preferably 80~170 DEG C, and more preferable 100~135 DEG C.Time is preferably 1~5h.
The present invention is to the dewatering type and is not particularly limited, and can be mode well known to those skilled in the art, such as divide Hydrophone reflux dewatering, is dehydrated using spray drying device, or passes through belt vacuum drying and dehydrating.
After salt, chlorine carboxylate is added, carries out condensation reaction, the mixing that benzene oxycarboxylic acid ester and chlorate can be obtained is molten Liquid.
The present invention is to the adding manner of the chlorine carboxylate and is not particularly limited, it is preferred to use the mode of dropwise addition.The drop The time added is preferably 1~5h, more preferable 2~3h.The temperature of the dropwise addition is preferably 60~170 DEG C.
The temperature of the condensation reaction is preferably 60~170 DEG C, and more preferable 100~130 DEG C.Time is preferably 0.1~2h, More preferable 0.3~1h.
After reaction, currently preferred, with 1-5 DEG C/min, more preferably with the speed of 2.5 DEG C/min by system temperature It is down to 37-42 DEG C, more preferably near 39-41 DEG C, and ultrasound, so that chlorate crystal grain is become larger, be filtered to remove chlorate, has realized Completely without discharge of wastewater.
The frequency of the ultrasound is preferably 20KHz-45KHz, more preferable 30KHz-35KHz.
The partial size of the chlorate crystal grain is preferably 100~200 mesh, more preferable 150~200 mesh.
It is oily to be mutually distilled to recover after solvent to get benzene oxycarboxylic acid ester is arrived.
Compared with prior art, the present invention provides a kind of preparation methods of benzene oxycarboxylic acid ester, comprising the following steps: A) phenol Class compound and alkaline hydrated oxide are dehydrated into salt in organic solvent, obtain the salt of phenolic compound；B) after at salt, chlorine is added Carboxylate carries out condensation reaction, obtains the mixed solution of benzene oxycarboxylic acid ester and chlorate；C) with the speed of 1-5 DEG C/min by body It is that temperature is down to 37-42 DEG C, and ultrasound, so that chlorate crystal grain is become larger, be filtered to remove chlorate；The organic solvent be toluene, Any two kinds of mixture in dimethylbenzene, chlorobenzene, phenol, butanol and isobutanol.The present invention carries out in mixed organic solvents Phenol is dehydrated into salt, and system remains uniform state in dehydration, realizes continuous production, and dehydration efficiency compared with Height, entire production process efficiency are higher.And raw material is easy to get, with short production cycle, energy consumption is lower, lower production costs.And it crosses and filters out The chlorate generated is removed, realize waste water zero generates zero-emission.
In addition, the present invention carries out condensation reaction using phenol and chlorine carboxylate in anhydrous system, ɑ-chloro carboxylic is reduced The hydrolysis of acid, thereby reduces its consumption, while greatly reducing the generation of chlorate, the experimental results showed that, present invention synthesis 1mol benzene oxycarboxylic acid ester, abraum salt yield are reduced to 1.01mol from 2.45mol, and abraum salt yield reduces 60% or so, prevented height The generation of salt waste water solves metal chloride bring wastewater problem.Wastewater flow rate is reduced to 2~3 tons from 25 tons simultaneously, reduces 90% or more.And effectively prevent the prior art because chlorobenzene oxycarboxylic acid sterling separation of solid and liquid caused by effective component Loss improves the yield of effective component, product purity height, high income.
The present invention does not use chlorophenol as raw material, has prevented the huge smell problem of chlorophenol bring, dislikes without two English generates；The benzene oxycarboxylic acid ester being prepared can carry out chlorination reaction again and obtain 2,4-D class compound.
Specific embodiment
In order to further illustrate the present invention, below with reference to embodiment to the preparation method of benzene oxycarboxylic acid ester provided by the invention It is described in detail.
Embodiment 1
By phenol 47.6g (0.5mol), toluene 120g, 30g butanol, the sodium hydrate aqueous solution of mass fraction 32% 62.8g (0.5mol) is mixed, and is warming up to 140 DEG C or so, band water reacts 1 hour.Neutralizer is slightly cooled to 120 DEG C, It is added dropwise methyl chloroacetate 53.8g (0.495mol), is added dropwise within 4 hours, is warming up to 146 DEG C, insulation reaction 2 hours.It will reaction Liquid is cooled to 39 DEG C with 2.5 DEG C per minute, and promotes to crystallize with 30KHz ultrasonic wave in the process, and size of microcrystal is 150 mesh, then Filtering adds 20g fresh toluene washing filter cake, merges organic layer and separate in vacuum distillation, obtain product 81.1g, purity 99.1%, yield 95.8%.
Comparative example 1
By phenol 47.6g (0.5mol), toluene 150g, the sodium hydrate aqueous solution 62.8g of mass fraction 32% (0.5mol) is mixed, and is warming up to 140 DEG C or so, band water reacts 1 hour.Salt 25g is precipitated in reaction system.Slightly by neutralizer It is micro- to be cooled to 120 DEG C, it is added dropwise methyl chloroacetate 53.8g (0.495mol), is added dropwise within 4 hours, be warming up to 146 DEG C, heat preservation is anti- It answers 2 hours.Reaction solution is cooled to 100 DEG C, 150g water is added, adjusts pH to 7, stratification, the extraction of 20g toluene is added in water layer, Organic layer is separated in vacuum distillation, obtains product 78.3g, purity 97.9%, yield 91.3%.
Comparative example 2
By phenol 47.6g (0.5mol), 150g butanol, the sodium hydrate aqueous solution 62.8g of mass fraction 32% (0.5mol) is mixed, and is warming up to 140 DEG C or so, band water reacts 1 hour.Salt 9g is precipitated in reaction system.Slightly by neutralizer It is micro- to be cooled to 120 DEG C, it is added dropwise methyl chloroacetate 53.8g (0.495mol), is added dropwise within 4 hours, be warming up to 146 DEG C, heat preservation is anti- It answers 2 hours.Reaction solution is cooled to 100 DEG C, 150g water is added, adjusts pH to 7, stratification, the extraction of 20g toluene is added in water layer, Organic layer is separated in vacuum distillation, obtains product 79.1g, purity 97.7%, yield 92.3%.
Embodiment 2
By phenol 94.5g (1mol), toluene 200g, 100g butanol.The sodium hydrate aqueous solution 83.3g of mass fraction 48% (1mol) is mixed, and is warming up to 120 DEG C, and band water reacts 4 hours, and neutralizer is slightly cooled to 110 DEG C, and monoxone is added dropwise Methyl esters 108g (0.99mol) is added dropwise for 4 hours, is warming up to 120 DEG C, insulation reaction 2 hours.Under ultrasonication per minute 2.5 DEG C are cooled to 39 DEG C to 40 DEG C, and promote to crystallize with 30KHz ultrasonic wave in the process, and size of microcrystal is 150 mesh, are obtained by filtration Filter cake and filtrate wash filter cake with 100g toluene in two times, merge and organic layer is added and then separation is evaporated in vacuo, obtain product 161.8g, purity 99.2%, yield 97.2%.
Embodiment 3
By phenol 94.5g (1mol), dimethylbenzene 200g, 100g butanol.The sodium hydrate aqueous solution of mass fraction 48% 83.3g (1mol) is mixed, and is warming up to 120 DEG C, and band water reacts 4 hours, and neutralizer is slightly cooled to 110 DEG C, and chlorine is added dropwise Methyl acetate 108g (0.99mol) is added dropwise for 4 hours, is warming up to 120 DEG C, insulation reaction 2 hours.It is every under ultrasonication 2.5 DEG C of minute is cooled to 39 DEG C to 40 DEG C, and promotes to crystallize with 30KHz ultrasonic wave in the process, and size of microcrystal is 150 mesh, filtering Filter cake and filtrate are obtained, filter cake is washed in two times with 100g toluene, merges and organic layer is added and then separation is evaporated in vacuo, obtain product 162.3g, purity 99.1%, yield 97.5%.
Embodiment 4
By phenol 94.5g (1mol), toluene 200g, 100g isobutanol, the sodium hydrate aqueous solution of mass fraction 48% 83.3g (1mol) is mixed, and is warming up to 120 DEG C, and band water reacts 4 hours, and neutralizer is slightly cooled to 110 DEG C, and chlorine is added dropwise Methyl acetate 108g (0.99mol) is added dropwise for 4 hours, is warming up to 120 DEG C, insulation reaction 2 hours.It is every under ultrasonication 2.5 DEG C of minute is cooled to 40 DEG C, and promotes to crystallize with 30KHz ultrasonic wave in the process, and size of microcrystal is 150 mesh, and filter is obtained by filtration Cake and filtrate wash filter cake with 100g toluene in two times, merge and organic layer is added and then separation is evaporated in vacuo, obtain product 160.6g, purity 99.1%, yield 97.1%.
By above-described embodiment and comparative example it is found that preparation method provided by the invention yield with higher and purity.
The above description of the embodiment is only used to help understand the method for the present invention and its core ideas.It should be pointed out that pair For those skilled in the art, without departing from the principle of the present invention, the present invention can also be carried out Some improvements and modifications, these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims (10)

1. a kind of preparation method of benzene oxycarboxylic acid ester, comprising the following steps:
A) phenolic compound and alkaline hydrated oxide are dehydrated into salt in organic solvent, obtain the salt of phenolic compound；
B) after at salt, chlorine carboxylate is added, carries out condensation reaction, obtains the mixed solution of benzene oxycarboxylic acid ester and chlorate；
C system temperature) is down to by 37-42 DEG C, and ultrasound with the speed of 1-5 DEG C/min, so that chlorate crystal grain is become larger, is filtered to remove Chlorate；
The organic solvent is any two kinds of mixture in toluene, dimethylbenzene, chlorobenzene, phenol, butanol and isobutanol.
2. preparation method according to claim 1, which is characterized in that the organic solvent is made of solvent A and solvent B, Any one of the solvent A in toluene, dimethylbenzene and chlorobenzene, the solvent B are any in butanol and isobutanol It is a kind of.
3. preparation method according to claim 2, which is characterized in that the mass ratio of the solvent A and solvent B be (2~ 4): 1.
4. preparation method according to claim 1, which is characterized in that the phenolic compound is phenol or o-cresol；Institute Stating alkaline hydrated oxide is sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide or aluminium hydroxide.
5. preparation method according to claim 1, which is characterized in that the mass ratio of the phenolic compound and organic solvent For 1:(2~20).
6. preparation method according to claim 1, which is characterized in that the temperature for being dehydrated into salt is 80~170 DEG C.
7. preparation method according to claim 1, which is characterized in that the adding manner of the chlorine carboxylate is to be added dropwise, institute The temperature for stating dropwise addition is 60~170 DEG C, and the time of dropwise addition is 1~5h.
8. preparation method according to claim 1, which is characterized in that the temperature of the condensation reaction is 60~170 DEG C, when Between be 0.1~2h.
9. preparation method according to claim 1, which is characterized in that the frequency of the ultrasound is 20KHz-45KHz.
10. preparation method according to claim 1, which is characterized in that the partial size of the chlorate crystal grain is 100~200 Mesh.
CN201810225329.6A 2018-03-19 2018-03-19 A kind of preparation method of benzene oxycarboxylic acid ester Withdrawn CN108947823A (en)

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Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106242971A (en) * 2016-08-04 2016-12-21 山东省化工研究院 A kind of chloracetate synthesis in water technology and the new method of preparation 2,4 D esters thereof

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106242971A (en) * 2016-08-04 2016-12-21 山东省化工研究院 A kind of chloracetate synthesis in water technology and the new method of preparation 2,4 D esters thereof

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