CN108715581A - A kind of preparation method of 2- nitryl-4-thiamphenicol benzoic acids - Google Patents
A kind of preparation method of 2- nitryl-4-thiamphenicol benzoic acids Download PDFInfo
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- CN108715581A CN108715581A CN201810724556.3A CN201810724556A CN108715581A CN 108715581 A CN108715581 A CN 108715581A CN 201810724556 A CN201810724556 A CN 201810724556A CN 108715581 A CN108715581 A CN 108715581A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C315/00—Preparation of sulfones; Preparation of sulfoxides
- C07C315/04—Preparation of sulfones; Preparation of sulfoxides by reactions not involving the formation of sulfone or sulfoxide groups
Abstract
The present invention relates to technical field of organic synthesis, specially a kind of preparation method of 2- nitryl-4-thiamphenicol benzoic acids, it can preferably improve reacts phenomenon difficult and that products collection efficiency is relatively low caused by molecular oxidation current potential is higher in 2- nitro -4- methylsulfonyltoluene oxidation process.Its preparation process includes mainly：After 2- nitro -4- methylsulfonyltoluenes are mixed with iron powder, bromine is added thereto, is uniformly mixed, Sodamide is added thereto later, it is made fully to react, final product liquid is used for subsequent reactions material；Product liquid is mixed with sulfuric acid, nitric acid, stirs, oxidation reaction is carried out under catalysts conditions；Water is added into the mixed liquor of above-mentioned preparation, reaction is hydrolyzed；Water is added into material obtained above, filtering, centrifugation respectively obtain crude product and mother liquor；Nitrous acid is added into crude product obtained above, stirs, the reaction was complete；Sodium hypophosphite is added thereto, stirs, the reaction was complete, obtains product.
Description
Technical field
The present invention relates to technical field of organic synthesis, specially a kind of preparation method of 2- nitryl-4-thiamphenicol benzoic acids.
Background technology
2- nitryl-4-thiamphenicol benzoic acids are a kind of important organic synthesis intermediates, are widely used in dyestuff, medicine
With the production of pesticide.Currently, the preparation of 2- nitryl-4-thiamphenicol benzoic acids is generally using 2- nitro -4- methylsulfonyltoluenes as raw material,
It is carboxyl by the methyl oxidation on its phenyl ring, corresponding acid is prepared with this.
Publication No. is that the Chinese invention patent of CN106432006A discloses a kind of 2- nitryl-4-thiamphenicol benzoic acids nitrification
Technological process stirs mainly by mixing methylsulfonyltoluene with nitric acid, sulfuric acid, prepares 2- nitro -4- methylsulfonyl benzene first
Acid.
But due to connecting on the phenyl ring of 2- nitro -4- methylsulfonyltoluenes, there are two electron-withdrawing groups so that 2- nitros -4-
The HOMO energy of methylsulfonyltoluene is relatively low, more difficult in electrochemical reaction to lose electronics, to molecular oxidation current potential and reduction electricity
Position is higher, finally, keeps the 2- nitryl-4-thiamphenicol benzoic acid products collection efficiencies prepared using above-mentioned technical proposal relatively low.
Invention content
The object of the present invention is to provide a kind of preparation methods of 2- nitryl-4-thiamphenicol benzoic acids, can preferably change
Reacted caused by molecular oxidation current potential is higher in kind 2- nitro -4- methylsulfonyltoluene oxidation process difficult and products collection efficiency compared with
Low phenomenon.
The present invention above-mentioned technical purpose technical scheme is that：
A kind of preparation method of 2- nitryl-4-thiamphenicol benzoic acids, includes the following steps：
S1：Itrated compound 2- nitro -4- methylsulfonyltoluenes are mixed with sulfuric acid, nitric acid, stirs, is carried out under catalysts conditions
Oxidation reaction；
S2：Water is added in the mixed liquor prepared to S1, reaction is hydrolyzed；
S3：Water is added into material made from S2, filtering, centrifugation respectively obtain crude product and mother liquor；
S4：Liquid caustic soda and clear water are added in the crude product obtained into S3, to crude product alkali soluble；
S5：Clear water washing is added in mixed liquor into S4, filtrate and unreacted 2- nitros -4- methyl sulfone are recycled in filtering
Base toluene；
S6：Hydrochloric acid is added in filtrate into S5, carries out acid out；
S7：Clear water washing is added in mixed liquor into S6, centrifugation removes sewage；
S8：Product drying after being centrifuged in S7, packaging and storage.
Further, before carrying out S1 steps, increase S1 '：After 2- nitro -4- methylsulfonyltoluenes are mixed with iron powder, to
Bromine is wherein added, is uniformly mixed, Sodamide is added thereto later, it is made fully to react, by final product liquid
For subsequent reactions material.
Further, increase S3 ' between S3 and S4：Nitrous acid is added into crude product made from S3, stirs, has reacted
Entirely；Sodium hypophosphite is added thereto, stirs, the reaction was complete, centrifugation, and the solid product that centrifugation is obtained is anti-for follow-up alkali soluble
It answers.
Further, the mother liquor obtained in S3 steps is distilled, water and sulfuric acid is separately recovered.
Further, the tail gas that oxidation reaction in S1 steps generates is passed through in the water of the distillation recovery of the mother liquor in S3, is inhaled
Finish up gas.
Further, catalyst described in S1 is vanadic anhydride.
Further, liquid caustic soda described in S4 is sodium hydroxide.
Further, in S1 sulfuric acid used be volume ratio 70% sulfuric acid, the nitric acid is the nitric acid of volume ratio 65%.
The invention has the advantages that：
1. the present invention first handles it, makes on its phenyl ring before being aoxidized to substrate 2- nitro -4- methylsulfonyltoluenes
Bromine group is connected, recycles Sodamide that bromine group is substituted by amino, makes to connect amino on phenyl ring, to make to increase in molecular product
Add electron-donating group amino, reduces molecular oxidation current potential；The methyl on phenyl ring is aoxidized again later, prepares corresponding acid,
Due to before oxidation reaction, increasing electron-donating group on 2- nitro -4- methylsulfonyltoluenes, oxidizing potential reduces, therefore,
Oxidation reaction difficulty reduces, and reaction is made to be more easy to carry out.
2. the catalyst for preparing the reaction of 2- nitryl-4-thiamphenicol benzoic acids using 2- nitro -4- methylsulfonyltoluenes is five
V 2 O, but vanadic anhydride is severe poisonous chemicals, dosage is bigger, bigger to the pollution of environment, to operating personnel's
The influence of health is also more serious；And after increasing amino on the phenyl ring of 2- nitro -4- methylsulfonyltoluenes, the oxidation of reaction is difficult
Degree reduces, and the dosage of catalyst can greatly reduce, and so as to alleviate the severity of environmental pollution, weakens operating personnel's building ring
The danger level in border improves working environment.
3. before obtaining finished product, using the amino on nitrous acid and the phenyl ring of sodium hypophosphite elimination products, to obtain
To final product 2- nitryl-4-thiamphenicol benzoic acids.
4. the present invention obtains a large amount of mother liquors while obtaining crude product, mother liquor is distilled, water and sulfuric acid is separately recovered,
The water of recycling can be not only used for the hydrolysis in S2, and can be used for absorbing the tail gas in S1；The sulfuric acid of recycling can be used as in S1
Reactant sulfuric acid improves material utilization to reduce the wasting of resources.
Description of the drawings
To describe the technical solutions in the embodiments of the present invention more clearly, make required in being described below to embodiment
Attached drawing is briefly described, it should be apparent that, drawings in the following description are only some embodiments of the invention, for
For those of ordinary skill in the art, without creative efforts, other are can also be obtained according to these attached drawings
Attached drawing.
Fig. 1 is a kind of technique of the preparation method embodiment 1 and embodiment 2 of 2- nitryl-4-thiamphenicol benzoic acids of the present invention
Flow chart.
Fig. 2 is a kind of technique of the preparation method embodiment 3 and embodiment 4 of 2- nitryl-4-thiamphenicol benzoic acids of the present invention
Flow chart.
Specific implementation mode
Technical solution is clearly and completely described below in conjunction with specific embodiments of the present invention.Obviously, described
Embodiment be only the present invention a part of the embodiment, instead of all the embodiments.Based on the embodiment of the present invention, ability
The every other embodiment that domain those of ordinary skill is obtained without making creative work, belongs to guarantor of the present invention
The range of shield.
The present invention discloses a kind of preparation methods of 2- nitryl-4-thiamphenicol benzoic acids, shown in each embodiment specific as follows.
Embodiment 1
S1：By the sulfuric acid 2000kg of itrated compound 2- nitros -4- methylsulfonyltoluenes 650kg and 70%, 65% nitric acid 430kg
Mixing, stirs evenly, and 2kg catalyst vanadic anhydrides are added thereto, and stirring carries out oxidation reaction；It is produced in reaction process
Raw tail gas nitric oxide is absorbed with water.
S2：800kg water is added in the mixed liquor prepared to S1, reaction is hydrolyzed in stirring.
S3：300kg water, stirring are added into mixture made from S2, filtering, centrifugation respectively obtain about 600kg crude products
With 3447kg mother liquors.Mother liquor is distilled, water and sulfuric acid are respectively obtained, the water of recycling can be used to the hydrolysis in S2, and can
For absorbing the tail gas in S1；The sulfuric acid of recycling can be used as the reactant sulfuric acid in S1.
S4：Liquid caustic soda (40% sodium hydroxide) 220kg and clear water 1500kg is added in the crude product obtained into S3, to thick
Product alkali soluble.
S5：The washing of 100kg clear water is added in mixed liquor into S4, filtrate about 2370kg and unreacted is recycled in filtering
2- nitro -4- methylsulfonyltoluenes 50kg.
S6：25% hydrochloric acid 300kg is added in filtrate into S5, carries out acid out.
S7：Clear water 500kg washings, 8000rpm centrifugations, removal sewage 2650kg are added in mixed liquor into S6.
S8：Product 2- nitryl-4-thiamphenicol benzoic acids 520kg dryings after being centrifuged in S7, remove the steam of 20kg, will
Product packaging and storage after drying.
Embodiment 2
S1：By the sulfuric acid 1500kg of itrated compound 2- nitros -4- methylsulfonyltoluenes 650kg and 70%, 65% nitric acid 400kg
Mixing, stirs evenly, and 2kg catalyst vanadic anhydrides are added thereto, and stirring carries out oxidation reaction；It is produced in reaction process
Raw tail gas nitric oxide is absorbed with water.
S2：1000kg water is added in the mixed liquor prepared to S1, reaction is hydrolyzed in stirring.
S3：300kg water, stirring are added into mixture made from S2, filtering, centrifugation respectively obtain about 550kg crude products
With 3300kg mother liquors.Mother liquor is distilled, water and sulfuric acid are respectively obtained, the water of recycling can be not only used for the hydrolysis in S2, and can
For absorbing the tail gas in S1；The sulfuric acid of recycling can be used as the reactant sulfuric acid in S1.
S4：Liquid caustic soda (45% sodium hydroxide) 220kg and clear water 1500kg is added in the crude product obtained into S3, to thick
Product alkali soluble.
S5：The washing of 100kg clear water is added in mixed liquor into S4, filtrate about 2250kg and unreacted is recycled in filtering
2- nitro -4- methylsulfonyltoluenes 40kg.
S6：25% hydrochloric acid 300kg is added in filtrate into S5, carries out acid out.
S7：Clear water 500kg washings, 8000rpm centrifugations, removal sewage about 2500kg are added in mixed liquor into S6.
S8：Product 2- nitryl-4-thiamphenicol benzoic acids 450kg dryings after being centrifuged in S7, remove the steam of about 20kg,
By the product packaging and storage after drying.
Embodiment 3
S1'：It by itrated compound 2- nitros -4- methylsulfonyltoluenes 650kg and iron powder 10kg, mixes, stirring, and gradually thereto
Bromine 300kg is added, is uniformly mixed, after reaction, Sodamide 280kg is added thereto, reaction is abundant, and being retained in container has
Product liquid and iron powder precipitation.
S1：Product liquid in S1 is mixed with 70% sulfuric acid 2000kg, 65% nitric acid 430kg, is stirred evenly, and
0.5kg catalyst vanadic anhydrides are added thereto, stirring carries out oxidation reaction；The tail gas one generated in reaction process aoxidizes
Nitrogen is absorbed with water.
S2：800kg water is added in the mixed liquor prepared to S1, reaction is hydrolyzed in stirring.
S3：300kg water, stirring are added into mixture made from S2, filtering, centrifugation respectively obtain about 850kg crude products
With 3300kg mother liquors.Mother liquor is distilled, water and sulfuric acid are respectively obtained, the water of recycling can be used to the hydrolysis in S2, and can
For absorbing the tail gas in S1；The sulfuric acid of recycling can be used as the reactant sulfuric acid in S1.
S3'：Nitrous acid 200kg is added into crude product made from S3, stirring, the reaction was complete；Hypophosphorous acid is added thereto
Sodium 150kg, stirring, the reaction was complete, and centrifugation, the solid product that centrifugation is obtained is reacted for follow-up alkali soluble.
S4：Liquid caustic soda (40% sodium hydroxide) 220kg and clear water 1500kg is added in the crude product obtained into S3, to thick
Product alkali soluble.
S5：The washing of 100kg clear water is added in mixed liquor into S4, filtrate about 2400kg and unreacted is recycled in filtering
2- nitro -4- methylsulfonyltoluenes 30kg.
S6：25% hydrochloric acid 300kg is added in filtrate into S5, carries out acid out.
S7：Clear water 500kg washings, 8000rpm centrifugations, removal sewage 2500kg are added in mixed liquor into S6.
S8：Product 2- nitryl-4-thiamphenicol benzoic acids 600kg dryings after being centrifuged in S7, remove the steam of about 20kg,
By the product packaging and storage after drying.
Embodiment 4
S1'：It by itrated compound 2- nitros -4- methylsulfonyltoluenes 600kg and iron powder 8kg, mixes, stirring, and gradually thereto
Bromine 280kg is added, is uniformly mixed, after reaction, Sodamide 280kg is added thereto, reaction is abundant, and being retained in container has
Product liquid and iron powder precipitation.
S1：Product liquid in S1 is mixed with 70% sulfuric acid 2000kg, 65% nitric acid 430kg, is stirred evenly, and
0.3kg catalyst vanadic anhydrides are added thereto, stirring carries out oxidation reaction；The tail gas one generated in reaction process aoxidizes
Nitrogen is absorbed with water.
S2：700kg water is added in the mixed liquor prepared to S1, reaction is hydrolyzed in stirring.
S3：250kg water, stirring are added into mixture made from S2, filtering, centrifugation respectively obtain about 800kg crude products
With 3000kg mother liquors.Mother liquor is distilled, water and sulfuric acid are respectively obtained, the water of recycling can be used to the hydrolysis in S2, and can
For absorbing the tail gas in S1；The sulfuric acid of recycling can be used as the reactant sulfuric acid in S1.
S3'：Nitrous acid 150kg is added into crude product made from S3, stirring, the reaction was complete；Hypophosphorous acid is added thereto
Sodium 100kg, stirring, the reaction was complete, and centrifugation, the solid product that centrifugation is obtained is reacted for follow-up alkali soluble.
S4：Liquid caustic soda (40% sodium hydroxide) 220kg and clear water 1500kg is added in the crude product obtained into S3, to thick
Product alkali soluble.
S5：The washing of 100kg clear water is added in mixed liquor into S4, filtrate about 2000kg and unreacted is recycled in filtering
2- nitro -4- methylsulfonyltoluenes 20kg.
S6：25% hydrochloric acid 300kg is added in filtrate into S5, carries out acid out.
S7：Clear water 500kg washings, 8000rpm centrifugations, removal sewage 2500kg are added in mixed liquor into S6.
S8：Product 2- nitryl-4-thiamphenicol benzoic acids about 550kg dryings after being centrifuged in S7, remove the water of about 18kg
Vapour, by the product packaging and storage after drying.
Analysis of experimental results
By the various embodiments described above experimental result it is found that the experimental method of each embodiment can successfully utilize 2- nitro -4- first
Sulfuryl toluene is prepared in 2- nitryl-4-thiamphenicol benzoic acids, especially embodiment 3 and embodiment 4, first to itrated compound 2- nitros-
4- methylsulfonyltoluenes are handled, and are first made to connect bromine group on phenyl ring, then bromine group is substituted by amino, are made to connect ammonia on phenyl ring
Base reduces molecular oxidation current potential to make to increase in molecular product electron-donating group；Oxygen is carried out to the methyl on phenyl ring again later
Change, prepare corresponding acid, since before oxidation reaction, electron-donating group is increased on 2- nitro -4- methylsulfonyltoluenes, aoxidizes
Current potential reduces, and significantly less to the dosage of catalyst vanadic anhydride, vanadic anhydride is severe poisonous chemicals, and dosage subtracts
The severity for alleviating environmental pollution less reduces the danger level of operating personnel's working environment；Before obtaining finished product, utilize
Nitrous acid and sodium hypophosphite eliminate the amino on phenyl ring, to obtain final product 2- nitryl-4-thiamphenicol benzoic acids.Embodiment 3
With not only the dosage of severe poisonous chemicals catalyst vanadic anhydride greatly reduces in embodiment 4, and its products collection efficiency is opposite implements
Example 1 and embodiment 2 are promoted, and the safety of entire operating environment makes moderate progress.
Claims (8)
1. a kind of preparation method of 2- nitryl-4-thiamphenicol benzoic acids, which is characterized in that include the following steps：
S1：Itrated compound 2- nitro -4- methylsulfonyltoluenes are mixed with sulfuric acid, nitric acid, stirs, is aoxidized under catalysts conditions
Reaction；
S2：Water is added in the mixed liquor prepared to S1, reaction is hydrolyzed；
S3：Water is added into material made from S2, filtering, centrifugation respectively obtain crude product and mother liquor；
S4：Liquid caustic soda and clear water are added in the crude product obtained into S3, to crude product alkali soluble；
S5：Clear water washing is added in mixed liquor into S4, filtrate and unreacted 2- nitros -4- methylsulfonyl first are recycled in filtering
Benzene；
S6：Hydrochloric acid is added in filtrate into S5, carries out acid out；
S7：Clear water washing is added in mixed liquor into S6, centrifugation removes sewage；
S8：Product drying after being centrifuged in S7, packaging and storage.
2. a kind of preparation method of 2- nitryl-4-thiamphenicol benzoic acids according to claim 1, it is characterised in that：Into
Before row S1 steps, increase S1 '：After 2- nitro -4- methylsulfonyltoluenes are mixed with iron powder, bromine is added thereto, is stirred
Uniformly, Sodamide is added thereto later, it is made fully to react, final product liquid is used for subsequent reactions material.
3. a kind of preparation method of 2- nitryl-4-thiamphenicol benzoic acids according to claim 2, it is characterised in that：In S3
Increase S3 ' between S4：Nitrous acid is added into crude product made from S3, stirs, the reaction was complete；Hypophosphorous acid is added thereto
Sodium, stirring, the reaction was complete, and centrifugation, the solid product that centrifugation is obtained is reacted for follow-up alkali soluble.
4. a kind of preparation method of 2- nitryl-4-thiamphenicol benzoic acids according to claim 1, it is characterised in that：By S3
The mother liquor distillation obtained in step, is separately recovered water and sulfuric acid.
5. a kind of preparation method of 2- nitryl-4-thiamphenicol benzoic acids according to claim 4, it is characterised in that：By S1
The tail gas that oxidation reaction generates in step is passed through in the water of the distillation recovery of the mother liquor in S3, absorbs tail gas.
6. a kind of preparation method of 2- nitryl-4-thiamphenicol benzoic acids according to claim 1, it is characterised in that：In S1
The catalyst is vanadic anhydride.
7. a kind of preparation method of 2- nitryl-4-thiamphenicol benzoic acids according to claim 1, it is characterised in that：In S4
The liquid caustic soda is sodium hydroxide.
8. a kind of preparation method of 2- nitryl-4-thiamphenicol benzoic acids according to claim 1, it is characterised in that：In S1
Sulfuric acid used is the sulfuric acid of volume ratio 70%, and the nitric acid is the nitric acid of volume ratio 65%.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111302984A (en) * | 2020-04-09 | 2020-06-19 | 利民化学有限责任公司 | Method for recycling acid in synthesis of 2-nitro-4-methylsulfonylbenzoic acid |
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2018
- 2018-07-04 CN CN201810724556.3A patent/CN108715581A/en not_active Withdrawn
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111302984A (en) * | 2020-04-09 | 2020-06-19 | 利民化学有限责任公司 | Method for recycling acid in synthesis of 2-nitro-4-methylsulfonylbenzoic acid |
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Application publication date: 20181030 |