CN104557639B - Method of preparing 2-nitro-4-methylsulfonyl benzoic acid - Google Patents
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Abstract
The invention discloses a novel method of preparing 2-nitro-4-methylsulfonyl benzoic acid. The target product which is 2-nitro-4-methylsulfonyl benzoic acid is prepared by carrying out reaction by adopting an oxidation reaction device with a self-priming stirrer, wherein 2-nitro-4-methylsulfonyltoluene is used as the raw material, sulfuric acid is used as a reaction medium, a transition metal oxide is used as the catalyst, and oxygen is introduced in the course of reaction. The method provided by the invention has the advantage that the reaction condition is easy to control, the production cost is low, and the amount of the generated three wastes is reduced.
Description
Technical field
The invention belongs to organic synthesis field, more particularly to a kind of method for preparing 2- nitryl-4-thiamphenicol benzoic acids.
Background technology
2- nitryl-4-thiamphenicol benzoic acids (2-Nitro-4-methylsulfonylbenzoic acid；Abbreviation NMSBA)
It is important organic synthesis intermediate, there is larger using value in producer faces such as dyestuff, medicine and agricultural chemicals.Especially in agriculture
Prescription face, is the important intermediate for synthesizing mesotrione.Mesotrione belongs to three ketones herbicide, is a kind of efficient corn field
Herbicides special, is used widely in developed country.The domestic synthesis technique due to 2- nitryl-4-thiamphenicol benzoic acids not into
It is ripe, limit mesotrione application at home.Therefore the improvement to the synthesis technique of 2- nitryl-4-thiamphenicol benzoic acids seems
It is very urgent.
2- nitro -4- methylsulfonyltoluenes directly prepare the method for oxidation of 2- nitryl-4-thiamphenicol benzoic acids can be divided into：Chemistry
Oxidizing process and liquid-phase air oxidation.Chemical oxidization method mainly has：Sodium dichromate method, permanganimetric method, sodium hypochlorite oxidization
With nitric acid oxidation method etc..
CN201010258725 provides a kind of production method of 2- nitryl-4-thiamphenicol benzoic acids, with the concentrated sulfuric acid as anti-
Answer medium molten, methylsulfonyltoluene is nitrified into into 2- nitro -4- methylsulfonyltoluenes with nitration mixture (red fuming nitric acid (RFNA) and the concentrated sulfuric acid are constituted)；Finally
Using potassium permanganate oxidation 2- nitro -4- methylsulfonyltoluenes into 2- nitryl-4-thiamphenicol benzoic acids, single step yield 90% with
On, average yield reaches 85%.Oxidant used by the method is expensive, generates thinner MnO2Post processing is difficult, and waste residue amount is big.For
Avoid using expensive oxidant, Helmut Hagen et al. research nitric acid as oxidant, using 70% sulfuric acid as reaction
Medium, vanadic anhydride is catalyst, and is passed through dry oxygen, and the yield of 2- nitryl-4-thiamphenicol benzoic acids reaches 83%.
The oxidant of the method is cheap, and operation is easy, and with higher yield, but produce the toxic gases such as NO.Liquid phase
, because with environmental friendliness, receiving significant attention the features such as with low cost, the method reaction yield is low, equipment work for air oxidation process
Skill has high demands, it is difficult to large-scale application.
In sum, current chemical oxidization method reaction condition is gently easily controllable, but many is faced in actual production asks
Topic；Liquid phase air oxidationization is dfficult to apply at present in industrial production.
The content of the invention
It is an object of the invention to provide one kind can reduce three wastes yield, improve reaction yield, production cost is reduced
2- nitryl-4-thiamphenicol benzoic acid preparation methods.
To realize the purpose of the present invention, the present invention adopt technical scheme for:
A kind of method for preparing 2- nitryl-4-thiamphenicol benzoic acids,
Reaction equation is as follows,
With 2- nitro -4- methylsulfonyltoluenes as raw material, transition metal oxide as catalyst, sulfuric acid as solvent, closed
Oxygen is passed through under stirring condition, and is slowly added dropwise nitric acid, at 130-170 DEG C 5-10h is reacted, obtain 2- nitro -4- methylsulfonyls
Benzoic acid.
It is preferred that, 2- nitro -4- methylsulfonyltoluenes, transition metal oxide, sulfuric acid are added to self-absorbing type stirrer
Closed reactor in, stirring and dissolving；Oxygen is passed through in reactor makes system pressure reach 0-1.6MPa, adjusts stirring speed
Degree, makes the gas holdup (volume) >=10% in reactant liquor, and is slowly added dropwise nitric acid, while to supplemental oxygen in system, making reaction
Gas holdup is maintained at (volume) >=10% in liquid, and system pressure remains at low malleation or slight positive pressure state (0-1.6MPa).
Reaction speed is controlled by adjusting the rate of addition and gas liquid ratio of nitric acid.2- nitro -4- methylsulfonyls are tracked using liquid chromatogram
The content of toluene, the reaction as content ＜ 0.1% reaches terminal.Reactant liquor is cooled to room temperature filtration, and filter cake is washed with water to neutrality,
It is obtained the 2- nitryl-4-thiamphenicol benzoic acids of high-quality after drying, content ＞ 98%, filtrated stock recovery, 2- nitros-
4- thiamphenicol benzoic acid yields are more than 90% (in terms of 2- nitro -4- methylsulfonyltoluenes).
Described system pressure be 0～0.5MPa, gas holdup 10～30% in reactant liquor.
Described system pressure be 0～0.1MPa, the gas holdup 15%～20% in reactant liquor.
System pressure in the course of reaction in reactor keeps constant or fluctuates；When system pressure floats,
Domain of walker is 0～0.1MPa.Pressure is in all the time barotropic state in system.
The transition metal oxide is the oxide of vanadium or cobalt；Transition metal oxide and 2- nitro -4- methylsulfonyl first
The weight of benzene compares 1:10～100.The preferred V of transition metal oxide2O5；V2O5Compare 1 with the weight of 2- nitro -4- methylsulfonyltoluenes:
10～100, preferably 1:40～60, most preferably 1:50.
The weight of the sulfuric acid and 2- nitro -4- methylsulfonyltoluenes is than 1～10:1, preferably 6～8:1, most preferably 7:1；Sulphur
Acid concentration is 70%～98%.
The concentration of nitric acid is 30～75wt%, and preferred concentration is 45%～55%, the consumption of nitric acid be raw material 2- nitros-
1-5 times of 4- methylsulfonyltoluene weight, the consumption of preferred nitric acid is 3 times of raw material 2- nitro -4- methylsulfonyltoluene weight.
The catalytic oxidation temperature is 138～140 DEG C, and the reaction time is 6～9h.
Gas on liquid level in reactor can be sucked and disperseed by the self-absorbing type stirrer that the present invention is adopted again when working
In liquid phase, so as to realize reacting gas interior circulation, Gas-liquid interfacial area is increased substantially, reach the mesh for improving reaction rate
's.The size of self-absorbing type stirrer gettering ability is more depending on structural shape, mounting means, speed of agitator and feed liquid property etc.
The factor of kind.Agitator paddle and reactor diameter than it is bigger, speed of agitator is higher, liquid-column height is lower, feed liquid proportion more greatly, gas
The proportion of body is less, then inspiratory capacity is bigger；Under conditions of device structure and material system are certain, inspiratory capacity depends on stirring speed
Degree.The self-absorbing type stirrer of any one structural shape can be adopted in the present invention, suitable suction is reached by adjusting mixing speed
Tolerance, the preferable reaction effect of acquisition.Recommend from self-priming hollow Scroll-type or hollow windmill-shaped agitator.
The inventive method has the advantage that：
The present invention carries out aoxidizing 2- nitro -4- methylsulfonyltoluenes using the closed reactor with self-suction stirrer
Reaction.Through substantial amounts of condition test, it is determined that suitable response parameter and reaction condition, improve reaction yield, oxidant is reduced
Usage amount, and three wastes yield is few.Specifically：
1st, oxidation reaction is carried out in the closed reactor with self-absorbing type stirrer, oxygen is interior in reaction unit to follow
Ring, directly oxidized being recycled in solution uses as oxidant to react NO of generation etc., improves reaction yield；
2nd, easily-controlled reaction conditions, post processing be simple, three wastes yield is few, with larger industrial utility value.
Specific embodiment
The following examples are used to further describe the present invention, but do not constitute limitation of the invention.
Embodiment 1
In reactors of the 500mL equipped with self-absorbing type stirrer, the sulfuric acid of 140g 75%, 20g 2- nitro -4- MSMs are added
Base toluene, 0.4g V2O5Stirring and dissolving, closed system connects oxygen storage tank, and regulation mixing speed makes the gas holdup in reactant liquor
(volume) reaches 15%, is gradually heating to 138～140 DEG C, and the nitric acid of 60g 50% is added in system in 5～6h, while to being
Supplemental oxygen in system, makes system pressure remain at 5 × 10-3MPa, reacts 3h, liquid chromatogram tracking 2- nitro -4- methylsulfonyls
During the content ＜ 0.1% of toluene, reaction terminates.Reactant liquor naturally cools to room temperature, filters, during filter cake is washed till with 100g clear water
Property, obtain 2- nitryl-4-thiamphenicol benzoic acids, content ＞ 98%, filtrate recovery, 2- nitro -4- methylsulfonyl benzene after being dried
Carboxylic acid Yield reaches 96.7% (in terms of 2- nitro -4- methylsulfonyltoluenes).1g products produce 6g waste water, do not produce waste gas and waste residue
Embodiment 2
By the sulfuric acid of 210g 75%, 30g 2- nitro -4- methylsulfonyltoluenes, 0.3g V2O5Add to self-priming stirring
In the closed reactor of device, oxygen is stirred and is passed through, adjustment temperature is made in reactant liquor to 155 DEG C by adjusting stir speed (S.S.)
Gas holdup (volume) reaches 15%；The nitric acid that 90g concentration is 50% is added dropwise, 6h is added dropwise, as the carrying out of reaction is mended in system
Fill oxygen, make system pressure remain at 5 × 10-3MPa.Reaction is controlled by adjusting the rate of addition and gas liquid ratio of nitric acid
Speed, drips reaction 2h, and when liquid chromatogram tracks the content ＜ 0.1% of 2- nitro -4- methylsulfonyltoluenes, reaction terminates.Instead
Liquid is answered to be cooled to room temperature filtration, filter cake 150g is washed to neutrality, the 2- nitro -4- methylsulfonyl benzene of high-quality is obtained after drying
Formic acid, the filtrated stock recovery of content ＞ 98%, the yield of 2- nitryl-4-thiamphenicol benzoic acids is 88.7%.
Embodiment 3
By the sulfuric acid of 70g 75%, 10g 2- nitro -4- methylsulfonyltoluenes, 1g V2O5Add to self-absorbing type stirrer
In closed reactor, oxygen is stirred and is passed through, adjustment temperature contains the gas in reactant liquor to 140 DEG C by adjusting stir speed (S.S.)
Rate (volume) reaches 15%；The nitric acid that 30g concentration is 70% is added dropwise, 7h is added dropwise.Supplemental oxygen in system is carried out with reaction,
System pressure is set to remain at 5 × 10-3MPa.Reaction speed is controlled by adjusting the rate of addition and gas liquid ratio of nitric acid.Drop
Reaction 3h is added, when liquid chromatogram tracks the content ＜ 0.1% of 2- nitro -4- methylsulfonyltoluenes, reaction terminates.Reactant liquor is cooled down
Filter to room temperature, filter cake 60g is washed to neutrality, the 2- nitryl-4-thiamphenicol benzoic acids of high-quality, content are obtained after drying
The filtrated stock recoveries of ＞ 98%, the yield of 2- nitryl-4-thiamphenicol benzoic acids is 90.6%.
Embodiment 4
The mother liquor that will be reclaimed in embodiment 1,20g 2- nitro -4- methylsulfonyltoluenes, 0.4g V2O5Add to self-priming
In the closed reactor of formula agitator, oxygen is stirred and is passed through, adjustment temperature makes reaction to 140 DEG C by adjusting stir speed (S.S.)
Gas holdup (volume) in liquid reaches 15%；The nitric acid that 60g concentration is 50% is added dropwise, 6h is added dropwise, as the carrying out of reaction is to being
Supplemental oxygen in system, makes system pressure remain at 5 × 10-3MPa.Controlled by adjusting the rate of addition and gas liquid ratio of nitric acid
Reaction speed processed, dropwise reaction 3h, liquid chromatogram tracks content ＜ 0.1% of 2- nitro -4- methylsulfonyltoluenes, and reaction terminates.
Reactant liquor is cooled to room temperature filtration, and filter cake 100g is washed to neutrality, the 2- nitro -4- methylsulfonyls of high-quality are obtained after drying
Benzoic acid, content ＞ 98%.Filtrated stock recovery, the yield of 2- nitryl-4-thiamphenicol benzoic acids is 95.6%.
Embodiment 5
Using the method for CN201010258725, using potassium permanganate as oxidant, by the concentrated sulfuric acids of 100g 90%, 30g
To methylsulfonyltoluene, cool to 0～4 DEG C, (ratio is 1 by 90% concentrated sulfuric acid and 60% nitric acid to add 60g:0.5), keep
Temperature is warming up to 20～30 DEG C at 0～4 DEG C, after adding, and adds 100g water, 2g potassium permanganate to be warming up to 50～60 DEG C, add
70g bis- is hydrated potassium bichromate, and 120g potassium bichromate solutions are warming up to 70～80 DEG C, react 5～6h.Reaction end is cooled to 20
DEG C once, add 200g water to stir 1～2h, filter.Filter cake 250g sodium hydrate aqueous solutions, agitation and filtration, filtrate uses dense salt
It is 1 that acid is adjusted to pH, and cold filtration is dried, and obtains product, yield 85.7%.The method production 1g products produce 25g waste water, and
And have a MnO2Waste residue is produced, and quantity of three wastes is larger.
Embodiment 6
By 3500kg75% sulfuric acid, 50kg 2- nitro -4- methylsulfonyltoluenes, 1kg V2O5Add to self-priming stirring
In the closed reactor of device, oxygen is stirred and is passed through, adjustment temperature makes reactant liquor to 138～140 DEG C by adjusting stir speed (S.S.)
In gas holdup (volume) reach 15%；The nitric acid that 150kg concentration is 50% is added dropwise, 6h is added dropwise, as the carrying out of reaction is to being
Supplemental oxygen in system, makes system pressure remain at 5 × 10-3MPa.Controlled by adjusting the rate of addition and gas liquid ratio of nitric acid
Reaction speed processed, drips reaction 2h, when liquid chromatogram tracks the content ＜ 0.1% of 2- nitro -4- methylsulfonyltoluenes, reaction knot
Beam.Reactant liquor is cooled to room temperature filtration, and filter cake 150kg is washed to neutrality, the 2- nitro -4- first of high-quality is obtained after drying
Sulfuryl benzoic acid, the filtrated stock recovery of content ＞ 98%, the yield of 2- nitryl-4-thiamphenicol benzoic acids be 95.3% (with
2- nitro -4- methylsulfonyltoluenes).158kg waste water is produced, waste gas and waste residue is not produced.Using potassium permanganate oxidation method, it is contemplated that produce
Raw 900kg waste water, and produce the waste residue of 5kg or so.
Claims (9)
1. a kind of method for preparing 2- nitryl-4-thiamphenicol benzoic acids, it is characterised in that：
2- nitro -4- methylsulfonyltoluenes, transition metal oxide, sulfuric acid are added to into the confined reaction with self-absorbing type stirrer
In kettle, stirring and dissolving；Closed reactor, being passed through oxygen makes system pressure reach 0～1.6MPa, adjusts mixing speed, makes reaction
Gas holdup (volume) >=10% in liquid, and nitric acid is slowly added dropwise, the supplemental oxygen in system keeps gas holdup in reactant liquor
(volume) >=10%；5～10h is reacted at 130～170 DEG C, 2- nitryl-4-thiamphenicol benzoic acids are obtained.
2. the method for preparing 2- nitryl-4-thiamphenicol benzoic acids according to claim 1, it is characterised in that：Described is
System pressure be 0～0.5MPa, gas holdup 10～30% in reactant liquor.
3. the method for preparing 2- nitryl-4-thiamphenicol benzoic acids according to claim 2, it is characterised in that：Described is
System pressure be 0～0.1MPa, the gas holdup 15%～20% in reactant liquor.
4. the method for preparing 2- nitryl-4-thiamphenicol benzoic acids according to claim 1, it is characterised in that：The reaction
During system pressure in reactor keep constant or fluctuate；When system pressure floats, domain of walker be 0～
0.1MPa。
5. the method for preparing 2- nitryl-4-thiamphenicol benzoic acids according to claim 1, it is characterised in that：The transition
Metal oxide is the oxide of vanadium or cobalt；Transition metal oxide compares 1 with the weight of 2- nitro -4- methylsulfonyltoluenes:10～
100。
6. the method for preparing 2- nitryl-4-thiamphenicol benzoic acids according to claim 1, it is characterised in that：The transition
Metal oxide is V2O5；V2O5Compare 1 with the weight of 2- nitro -4- methylsulfonyltoluenes:10～100.
7. the method for preparing 2- nitryl-4-thiamphenicol benzoic acids according to claim 1, it is characterised in that：The sulfuric acid
Compare 1 with the weight of 2- nitro -4- methylsulfonyltoluenes:1～10；Sulfuric acid concentration is 70%～98%.
8. the method for preparing 2- nitryl-4-thiamphenicol benzoic acids according to claim 1, it is characterised in that：The nitric acid
Concentration is 30～75wt%, and the consumption of nitric acid is 1～5 times of raw material 2- nitro -4- methylsulfonyltoluene weight.
9. the method for preparing 2- nitryl-4-thiamphenicol benzoic acids according to claim 1, it is characterised in that：The catalysis
Oxidizing reaction temperature is 138～140 DEG C, and the reaction time is 6～9h.
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| CN105017101B (en) * | 2015-08-08 | 2017-03-22 | 浙江大学 | Synthesizing method of 2-chloro-4-(methylsulfonyl)benzoic acid |
| CN105669504A (en) * | 2016-03-07 | 2016-06-15 | 山东润博生物科技有限公司 | Preparation method of 2-nitro-4-methyl sulphonyl benzoic acid |
| CN106496079B (en) * | 2016-09-12 | 2018-07-27 | 华东理工大学 | A kind of technique for producing 2- nitryl-4-thiamphenicol benzoic acids with Oxygen Catalytic Oxidation |
| CN107827790B (en) * | 2017-11-22 | 2024-07-02 | 浙江嘉化新材料有限公司 | Synthesis method of 1-methyl-4-methylsulfonyl benzene |
| CN113801046B (en) * | 2020-06-17 | 2023-06-13 | 北京颖泰嘉和生物科技股份有限公司 | Preparation method of 2-nitro-4-methylsulfonyl benzoic acid |
| CN111718264B (en) * | 2020-07-16 | 2021-12-03 | 江苏永安化工有限公司 | Method for co-producing 2-methyl-6-nitrobenzoic acid and 2-methyl-3-nitrobenzoic acid |
| WO2022024094A1 (en) * | 2020-07-31 | 2022-02-03 | Rallis India Limited | Process for preparation of mesotrione and its intermediates |
| CN114249675B (en) * | 2020-09-22 | 2023-11-21 | 北京颖泰嘉和生物科技股份有限公司 | Preparation method of 2-nitro-4-methylsulfonyl benzoic acid |
| CN112300033B (en) * | 2020-11-03 | 2023-10-13 | 湖北丰杯生物科技有限公司 | Device and method for fully continuously synthesizing 2-nitro-4-methylsulfonyl benzoic acid from 4-methylsulfonyl toluene |
| CN117715887A (en) * | 2021-06-29 | 2024-03-15 | 加尔达化学有限公司 | Preparation method of 2-nitro-4-methylsulfonyl benzoic acid |
| CN114195689A (en) * | 2021-11-29 | 2022-03-18 | 南京鹳山化工科技有限公司 | Novel synthesis process of 2-nitro-4-methylsulfonylbenzoic acid |
| CN114591176B (en) * | 2022-03-09 | 2023-09-05 | 济南大学 | Preparation method of 3-nitrophthalic acid |
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| US4781750A (en) * | 1985-08-27 | 1988-11-01 | Rohm And Haas Company | Herbicidally active enols |
| CN1038584A (en) * | 1988-06-24 | 1990-01-10 | 中国人民解放军第八一医院 | The extraction process of anticancer health-protecting tea extract |
| DE4235155A1 (en) * | 1992-10-19 | 1994-04-21 | Basf Ag | Process for the preparation of methylsulfonylbenzoic acids |
| CN2649170Y (en) * | 2003-10-28 | 2004-10-20 | 杭州原正化学工程技术装备有限公司 | Efficient self-absorption gas-liquid stirring device |
| CN100577613C (en) * | 2007-12-14 | 2010-01-06 | 嘉兴学院 | Method for oxidation of benzene ring side chain containing electron-attracting groups by combination of ozone and nitric acid |
| CN101503383B (en) * | 2009-03-16 | 2013-04-24 | 嘉兴学院 | Preparation of o-nitro p-methylsulfonylbenzoic acid |
| CN103626681B (en) * | 2012-08-20 | 2015-09-09 | 中国中化股份有限公司 | One prepares 4, the method for 4 '-dinitrostilbene-2,2 '-disulfonic acid |
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