CN108752247A - A kind of industrialized preparing process of the 2- nitryl-4-thiamphenicol benzoic acids of low stain - Google Patents
A kind of industrialized preparing process of the 2- nitryl-4-thiamphenicol benzoic acids of low stain Download PDFInfo
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- CN108752247A CN108752247A CN201810725924.6A CN201810725924A CN108752247A CN 108752247 A CN108752247 A CN 108752247A CN 201810725924 A CN201810725924 A CN 201810725924A CN 108752247 A CN108752247 A CN 108752247A
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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
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
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Abstract
The present invention relates to technical field of organic synthesis, the industrialized preparing process of the 2- nitryl-4-thiamphenicol benzoic acids of specially a kind of low stain, 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;Potassium nitrite and hydrochloric acid are added into crude product obtained above, stirring, 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, the 2- nitryl-4-thiamphenicol benzoic acids of specially a kind of low stain
Industrialized preparing process.
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 industrialized preparing process of the 2- nitryl-4-thiamphenicol benzoic acids of low stain,
It can preferably improve in 2- nitro -4- methylsulfonyltoluene oxidation process reacts tired caused by molecular oxidation current potential is higher
Difficulty and the relatively low phenomenon of products collection efficiency.
The present invention above-mentioned technical purpose technical scheme is that:
A kind of industrialized preparing process of the 2- nitryl-4-thiamphenicol benzoic acids of low stain, 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:Potassium nitrite and hydrochloric acid are added into crude product made from S3, stirs
It mixes, the reaction was complete;Sodium hypophosphite is added thereto, stirs, the reaction was complete, centrifugation, after the solid product that centrifugation obtains is used for
Continuous alkali soluble reaction.
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 the phenyl ring of potassium nitrite, hydrochloric acid and sodium hypophosphite elimination products,
To obtain final product 2- nitryl-4-thiamphenicol benzoic acids.With Asia is directly used in the other application documents applied on the same day
Nitric acid is compared, and the nitrous acid that potassium nitrite and hydrochloric acid of the present invention generate when reacting is reacted with the amino on phenyl ring immediately, is avoided
Directly using nitrous acid, there is a phenomenon where nitrous acid to decompose.
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 1 He of industrialized preparing process embodiment of the 2- nitryl-4-thiamphenicol benzoic acids of low stain of the present invention
The process flow chart of embodiment 2.
Fig. 2 is a kind of 3 He of industrialized preparing process embodiment of the 2- nitryl-4-thiamphenicol benzoic acids of low stain of the present invention
The process flow chart of embodiment 4.
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 industrialized preparing process of the 2- nitryl-4-thiamphenicol benzoic acids of low stain, specifically such as
Under shown in each embodiment.
Embodiment 1
S1:By itrated compound 2- nitros -4- methylsulfonyltoluenes 650kg and the sulfuric acid 2000kg of volume ratio 70%, volume ratio
65% nitric acid 430kg mixing, stirs evenly, and 2kg catalyst vanadic anhydrides are added thereto, stirring, aoxidize anti-
It answers;The tail gas nitric oxide generated in reaction process 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 itrated compound 2- nitros -4- methylsulfonyltoluenes 650kg and the sulfuric acid 1500kg of volume ratio 70%, volume ratio
65% nitric acid 400kg mixing, stirs evenly, and 2kg catalyst vanadic anhydrides are added thereto, stirring, aoxidize anti-
It answers;The tail gas nitric oxide generated in reaction process 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':Potassium nitrite 220kg, the hydrochloric acid 80kg stirrings of volume ratio 10%, reaction are added into crude product made from S3
Completely;Sodium hypophosphite 150kg is added thereto, stirring, the reaction was complete, and centrifugation, the solid product that centrifugation is obtained is for follow-up
Alkali soluble is reacted.
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 2450kg and unreacted is recycled in filtering
2- nitro -4- methylsulfonyltoluenes 25kg.
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 25kg,
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':Potassium nitrite 175kg, the hydrochloric acid 70kg stirrings of volume ratio 10%, reaction are added into crude product made from S3
Completely;Sodium hypophosphite 100kg is added thereto, stirring, the reaction was complete, and centrifugation, the solid product that centrifugation is obtained is for follow-up
Alkali soluble is reacted.
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 2150kg and unreacted is recycled in filtering
2- nitro -4- methylsulfonyltoluenes 25kg.
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 565kg dryings after being centrifuged in S7, remove the water of about 29kg
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
Potassium nitrite, hydrochloric acid and sodium hypophosphite eliminate the amino on phenyl ring, to obtain final product 2- nitryl-4-thiamphenicol benzoic acids.
Not only the dosage of severe poisonous chemicals catalyst vanadic anhydride greatly reduces in embodiment 3 and embodiment 4, and its products collection efficiency phase
Embodiment 1 and embodiment 2 are promoted, the safety of entire operating environment makes moderate progress.
Claims (8)
1. a kind of industrialized preparing process of the 2- nitryl-4-thiamphenicol benzoic acids of low stain, which is characterized in that including following step
Suddenly:
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 industrialized preparing process of the 2- nitryl-4-thiamphenicol benzoic acids of low stain according to claim 1,
It is characterized in that:Before carrying out S1 steps, increase S1 ':After 2- nitro -4- methylsulfonyltoluenes are mixed with iron powder, it is added thereto
Bromine is uniformly mixed, and Sodamide is added thereto later, it is made fully to react, by final product liquid for follow-up
Reaction mass.
3. a kind of industrialized preparing process of the 2- nitryl-4-thiamphenicol benzoic acids of low stain according to claim 2,
It is characterized in that:Increase S3 ' between S3 and S4:Potassium nitrite and hydrochloric acid are added into crude product made from S3, stirring has been 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.
4. a kind of industrialized preparing process of the 2- nitryl-4-thiamphenicol benzoic acids of low stain according to claim 1,
It is characterized in that:The mother liquor obtained in S3 steps is distilled, water and sulfuric acid is separately recovered.
5. a kind of industrialized preparing process of the 2- nitryl-4-thiamphenicol benzoic acids of low stain according to claim 4,
It is characterized in that: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, absorbs tail gas.
6. a kind of industrialized preparing process of the 2- nitryl-4-thiamphenicol benzoic acids of low stain according to claim 1,
It is characterized in that:Catalyst described in S1 is vanadic anhydride.
7. a kind of industrialized preparing process of the 2- nitryl-4-thiamphenicol benzoic acids of low stain according to claim 1,
It is characterized in that:Liquid caustic soda described in S4 is sodium hydroxide.
8. a kind of industrialized preparing process of the 2- nitryl-4-thiamphenicol benzoic acids of low stain according to claim 1,
It is characterized in that:Sulfuric acid used is the sulfuric acid of volume ratio 70% in S1, and the nitric acid is the nitric acid of volume ratio 65%.
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CN201810725924.6A CN108752247A (en) | 2018-07-04 | 2018-07-04 | A kind of industrialized preparing process of the 2- nitryl-4-thiamphenicol benzoic acids of low stain |
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CN201810725924.6A CN108752247A (en) | 2018-07-04 | 2018-07-04 | A kind of industrialized preparing process of the 2- nitryl-4-thiamphenicol benzoic acids of low stain |
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