CN101659635A - Preparation method of methyl p-tolyl sulfone - Google Patents
Preparation method of methyl p-tolyl sulfone Download PDFInfo
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- CN101659635A CN101659635A CN200910018412A CN200910018412A CN101659635A CN 101659635 A CN101659635 A CN 101659635A CN 200910018412 A CN200910018412 A CN 200910018412A CN 200910018412 A CN200910018412 A CN 200910018412A CN 101659635 A CN101659635 A CN 101659635A
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Abstract
The invention relates to a preparation method of methyl p-tolyl sulfone, which belongs to the technical field of sulphone preparation, in particular to a preparation method of the methyl p-tolyl sulfone by taking monochloro methane as a methylating agent for synthesis. The preparation method is characterized by taking p-toluenesulfonylchloride, anhydrous sodium sulfite, sodium bicarbonate and monochloro methane as synthesizing raw materials and comprising the following operation steps: a. salifying the p-toluenesulfonylchloride; b. synthesizing the methyl p-tolyl sulfone; c. adjusting pH, reducing the temperature and discharging; d. filtering, dehydrating and drying; and e. inspecting the quality and packaging and warehousing after qualification. The invention provides a preparation methodof the methyl p-tolyl sulfone without using a deadly poisonous compound of dimethyl sulfate as a raw material, and has safe operation, environmental protection, short production period, good productquality, high yield, low production cost and strong market competitiveness. The content of the methyl p-tolyl sulfone reaches up to 99.5 percent, and the yield of the methyl p-tolyl sulfone, which iscounted by the p-toluenesulfonylchloride of the raw material, is more than or equal to 85 percent.
Description
Technical field
The present invention is a kind of preparation method to methylsulfonyl toluene.The preparing technical field that belongs to sulfone.Relating in particular to the monochloro methane is the synthetic preparation method to methylsulfonyl toluene of methylating agent.
Background technology
To methylsulfonyl toluene is the important starting raw material of synthetic medicine, dyestuff, agricultural chemicals.Give mycin, R.D. 17345 etc. as first.In the prior art, utilize Tosyl chloride, under weak basic condition,, methylate with methyl-sulfate or methyl sodium sulphate again, come synthetic methylsulfonyl toluene through the S-WAT reduction.Technological deficiency is that employing methyl-sulfate severe toxicity chemical is a raw material, and is dangerous big during operation, contaminate environment; Production cycle is long, and poor product quality, productive rate are low; Cause the production cost height, the market competitiveness is poor.
A kind of no longer to adopt hypertoxic chemical methyl-sulfate be raw material, operational safety, protection environment; With short production cycle, good product quality, productive rate height; The production cost preparation method to methylsulfonyl toluene low, that the very strong market competitiveness is arranged is that people expect.
Summary of the invention
The objective of the invention is to avoid above weak point of the prior art, a kind of no longer to adopt hypertoxic chemical methyl-sulfate be raw material and provide, operational safety, protection environment; With short production cycle, good product quality, productive rate height; The preparation method that production cost is low, have the very strong market competitiveness to methylsulfonyl toluene.
Purpose of the present invention can reach by following measure:
Preparation method to methylsulfonyl toluene of the present invention is characterized in that with Tosyl chloride, sodium sulphite anhydrous 99.3, sodium bicarbonate, monochloro methane be synthesis material, comprises following operation steps:
A. Tosyl chloride salify:
Sodium sulphite anhydrous 99.3, sodium bicarbonate input are added in advance in the redox reaction still of entry according to drafting prescription; Stir down, be warming up to 40 ℃, stop heating; Temperature in the kettle is when rising to 40 ℃-50 ℃, and beginning slowly adds Tosyl chloride, and controlled temperature approximately added between 40 ℃-64 ℃ in 1.5-2.5 hour; 64 ℃ of insulation reaction 1.5 hours, finish following reaction:
Na
2SO
3+2NaHCO
3+C
7H
7ClO
2S
→2CO
2+H
2O+NaCl+Na
2SO
4+C
7H
7NaO
2S；
Drop into the gac of metering, insulation decolouring 50-60 minute, pump around circuit is filtered while hot, after backflow mother liquor to be recycled is as clear as crystal, enters the methylation reaction still, and is standby;
B. synthetic to methylsulfonyl toluene:
From step a methyl-sulfinic acid sodium salt solution is entered the methylation reaction still after, start stirring, be warming up to 60 ℃; Connect vacuum system, the still internal pressure is reduced to-0.07Mpa after, close vacuum valve; Begin to feed monochloro methane, the still internal pressure constantly rises, after the still internal pressure rises to 0.2Mpa, 82 ℃-93 ℃ of controlled temperature, between the pressure 0.20Mpa-0.30Mpa under the condition, continue to feed monochloro methane, the time that methylates, it was reaction end that the material in the still no longer absorbs gas between 18-19 hour.Finish following reaction:
C
7H
7SO
2Na+CH
3Cl→C
8H
10SO
2+NaCl；
C. regulate pH, cooling, discharging:
After methylation reaction finished, the pH of material under 80 ℃ of-85 ℃ of temperature, with alkali lye adjusting pH=9-12 and after stablizing, when being cooled to 50 ℃ with the interlayer recirculated cooling water, directly added cold water in reactor between 7-8, and temperature of charge is reduced to 40 ℃, and is to be filtered;
D. filter, dewater, dry:
40 ℃ material from step c is put into filter cylinder, filters; Filter cake is washed with water to pH=7.0, centrifuge dehydration, oven dry;
E. quality test, qualified back packing, warehouse-in.
Purpose of the present invention can also reach by following measure:
Preparation method to methylsulfonyl toluene of the present invention is characterized in that with Tosyl chloride, sodium sulphite anhydrous 99.3, sodium bicarbonate, monochloro methane be synthesis material; Comprise following operation steps:
A. Tosyl chloride salify:
Sodium sulphite anhydrous 99.3, sodium bicarbonate input are added in advance in the redox reaction still of entry according to drafting prescription; Stir down, be warming up to 40 ℃, stop heating; Temperature in the kettle is when rising to 50 ℃, and beginning slowly adds the Tosyl chloride controlled temperature between 50 ℃-64 ℃, adds in about 2 hours; 64 ℃ of insulation reaction 1.5 hours, finish following reaction:
Na
2SO
3+2NaHCO
3+C
7H
7ClO
2S
→2CO
2+H
2O+NaCl+Na
2SO
4+C
7H
7NaO
2S；
Drop into the gac of metering, insulation decolouring 50-60 minute, pump around circuit is filtered while hot, after backflow mother liquor to be recycled is as clear as crystal, enters the methylation reaction still, and is standby;
B. synthetic to methylsulfonyl toluene:
From step a methyl-sulfinic acid sodium salt solution is entered the methylation reaction still after, start stirring, be warming up to 60 ℃; Connect vacuum system, the still internal pressure is reduced to-0.07Mpa after, close vacuum valve; Begin to feed monochloro methane, the still internal pressure constantly rises, in 10-15 divides clock time, the still internal pressure is raised to 0.2Mpa, 85 ℃-90 ℃ of controlled temperature under the condition, continue to feed monochloro methane between the pressure 0.20Mpa-0.25Mpa, the time that methylates, it was reaction end that the material in the still no longer absorbs gas between 18-19 hour.Finish following reaction:
C
7H
7SO
2Na+CH
3Cl→C
8H
10SO
2+NaCl；
C. regulate pH, cooling, discharging:
After methylation reaction finished, the pH of material under 80 ℃ of-85 ℃ of temperature, with alkali lye adjusting pH=9-10 and after stablizing, when being cooled to 50 ℃ with the interlayer recirculated cooling water, directly added cold water in reactor between 7-8, and temperature of charge is reduced to 40 ℃, and is to be filtered;
D. filter, dewater, dry:
40 ℃ material from step c is put into filter cylinder, filters; Filter cake is washed with water to pH=7.0, centrifuge dehydration, oven dry;
E. quality test, qualified back packing, warehouse-in.
Preparation method to methylsulfonyl toluene of the present invention is characterized in that step b. synthetic to methylsulfonyl toluene, and its technological process is as follows:
From step a methyl-sulfinic acid sodium salt solution is entered the methylation reaction still after, start stirring, be warming up to 60 ℃; Connect vacuum system, the still internal pressure is reduced to-0.07Mpa after, close vacuum valve; Begin to feed monochloro methane, the still internal pressure constantly rises, after the still internal pressure is raised to 0.20Mpa, 86 ℃-88 ℃ of controlled temperature under the pressure 0.28Mpa condition, continue to feed monochloro methane, the time that methylates, it was reaction end that the material in the still no longer absorbs gas between 18-19 hour.Finish following reaction:
C
7H
7SO
2Na+CH
3Cl→C
8H
10SO
2+NaCl。
Preparation method to methylsulfonyl toluene of the present invention is characterized in that the productive rate to first sulfone toluene 〉=85% in the raw material Tosyl chloride.
Technical scheme of the present invention has following outstanding substantive distinguishing features and obvious improvement compared to existing technology:
1. provide that a kind of no longer to adopt hypertoxic chemical methyl-sulfate be raw material, operational safety, protection environment; With short production cycle, good product quality, productive rate height; The preparation method that production cost is low, have the very strong market competitiveness to methylsulfonyl toluene;
2. adopt monochloro methane as methylating agent, avoided adopting hypertoxic chemical methyl-sulfate; Operational safety, protection environment have improved labor condition greatly;
3 have shortened the production cycle greatly;
4. product reaches more than 99.5% the methylsulfonyl toluene level;
5. in the productive rate to first sulfone toluene 〉=85% of raw material Tosyl chloride;
6. the products production cost reduces significantly, has improved the competitiveness of product in market.
Embodiment
The present invention is described in further detail below in conjunction with embodiment:
Embodiment 1
With Tosyl chloride, sodium sulphite anhydrous 99.3, sodium bicarbonate, monochloro methane is synthesis material; Comprise following operation steps:
A. Tosyl chloride salify:
In the 2000L reactor, add 1400 kilograms of entry, 260 kilograms of sodium sulphite anhydrous 99.3s, 300 kilograms of sodium bicarbonates; Stir down, be warming up to 40 ℃, stop heating; Temperature in the kettle is when rising to 40 ℃-50 ℃, and beginning slowly adds 350 kilograms of Tosyl chlorides, and controlled temperature approximately added between 40 ℃-64 ℃ in 1.5-2.5 hour; 64 ℃ of insulation reaction 1.5 hours, finish following reaction:
Na
2SO
3+2NaHCO
3+C
7H
7ClO
2S
→2CO
2+H
2O+NaCl+Na
2SO
4+C
7H
7NaO
2S；
Drop into 15 kilograms of gacs, insulation decolouring 50-60 minute, pump around circuit is filtered while hot, after backflow mother liquor to be recycled is as clear as crystal, enters the methylation reaction still, and is standby;
B. synthetic to methylsulfonyl toluene:
From step a methyl-sulfinic acid sodium salt solution is entered the methylation reaction still after, start stirring, be warming up to 60 ℃; Connect vacuum system, the still internal pressure is reduced to-0.07Mpa after, close vacuum valve; Begin to feed monochloro methane, the still internal pressure constantly rises, and after the still internal pressure was raised to 0.2Mpa, 82 ℃ of controlled temperature under the pressure 0.20Mpa condition, continued to feed monochloro methane, methylate time 18-19 hour, and it is reaction end that the material in the still no longer absorbs gas.Finish following reaction:
C
7H
7SO
2Na+CH
3Cl→C
8H
10SO
2+NaCl；
C. regulate pH, cooling, discharging:
After methylation reaction finished, the pH of material under 80 ℃ of-85 ℃ of temperature, regulated pH=9 with alkali lye between 7-8, repetition measurement after 10 minutes, pH stablize constant after, when being cooled to 50 ℃ with the interlayer recirculated cooling water, directly add cold water in reactor, temperature of charge is reduced to 40 ℃, and is to be filtered;
D. filter, dewater, dry:
40 ℃ material from step c is put into filter cylinder, filters; Filter cake is washed with water to pH=7.0, centrifuge dehydration, oven dry;
E. quality test, qualified back packing, warehouse-in.
275.22 kilograms of products obtained therefroms are to methylsulfonyl toluene level 99.8%, in the productive rate 88% to first sulfone toluene of raw material Tosyl chloride.
Embodiment 2-9
According to prescription and the step of embodiment 1, prepare of the present invention to methylsulfonyl toluene according to the related process index that methylates of table 1.
Table 1
| Project | Example 2 | Example 3 | Example 4 | Example 5 | Example 6 | Example 7 | Example 8 | Example 9 |
| Methylate temperature (℃) | ??82 | ??90 | ??86 | ??84 | ??90 | ??93 | ??88 | ??91 |
| Pressure (Mpa) methylates | ??0.20 | ??0.23 | ??0.25 | ??0.30 | ??0.28 | ??0.30 | ??0.27 | ??0.26 |
| The liquid that methylates is regulated pH | ??10 | ??10 | ??9 | ??11 | ??9 | ??9 | ??12 | ??12 |
| Content (wt%) | ??99.55 | ??99.63 | ??99.58 | ??99.62 | ??99.80 | ??98.77 | ??99.82 | ??99.76 |
| Productive rate (%) | ??88.0 | ??86.5 | ??85.9 | ??85.6 | ??87.0 | ??86.5 | ??85.8 | ??88.0 |
Claims (3)
1. the preparation method to methylsulfonyl toluene is characterized in that with Tosyl chloride, sodium sulphite anhydrous 99.3, sodium bicarbonate, monochloro methane be synthesis material, comprises following operation steps:
A. Tosyl chloride salify:
Sodium sulphite anhydrous 99.3, sodium bicarbonate input are added in advance in the redox reaction still of entry according to drafting prescription, stir down, be warming up to 40 ℃, stop heating, temperature in the kettle is when rising to 40 ℃-50 ℃, beginning slowly adds Tosyl chloride, and controlled temperature approximately added between 40 ℃-64 ℃ in 1.5-2.5 hour; 64 ℃ of insulation reaction 1.5 hours, finish following reaction:
Na
2SO
3+2NaHCO
3+C
7H
7ClO
2S
→2CO
2+H
2O+NaCl+Na
2SO
4+C
7H
7NaO
2S；
Drop into the gac of metering, insulation decolouring 50-60 minute, pump around circuit is filtered while hot, after backflow mother liquor to be recycled is as clear as crystal, enters the methylation reaction still, and is standby;
B. synthetic to methylsulfonyl toluene:
From step a methyl-sulfinic acid sodium salt solution is entered the methylation reaction still after, start stirring, be warming up to 60 ℃; Connect vacuum system, the still internal pressure is reduced to-0.07Mpa after, close vacuum valve; Begin to feed monochloro methane, the still internal pressure constantly rises, after the still internal pressure rises to 0.2Mpa, 82 ℃-93 ℃ of controlled temperature, under the condition, continue to feed monochloro methane between the pressure 0.20Mpa-0.30Mpa, the time that methylates is between 18-19 hour, it is reaction end that material in the still no longer absorbs gas, finishes following reaction:
C
7H
7SO
2Na+CH
3Cl→C
8H
10SO
2+NaCl；
C. regulate pH, cooling, discharging:
After methylation reaction finished, the pH of material under 80 ℃ of-85 ℃ of temperature, with alkali lye adjusting pH=9-12 and after stablizing, when being cooled to 50 ℃ with the interlayer recirculated cooling water, directly added cold water in reactor between 7-8, and temperature of charge is reduced to 40 ℃, and is to be filtered;
D. filter, dewater, dry:
40 ℃ material from step c is put into filter cylinder, filters; Filter cake is washed with water to pH=7.0, centrifuge dehydration, oven dry;
E. quality test, qualified back packing, warehouse-in.
2. according to the preparation method to methylsulfonyl toluene of claim 1, it is characterized in that with Tosyl chloride, sodium sulphite anhydrous 99.3, sodium bicarbonate, monochloro methane be synthesis material, comprise following operation steps:
A. Tosyl chloride salify:
Sodium sulphite anhydrous 99.3, sodium bicarbonate input are added in advance in the redox reaction still of entry according to drafting prescription, stir down, be warming up to 40 ℃, stop heating; Temperature in the kettle is when rising to 50 ℃, and beginning slowly adds the Tosyl chloride controlled temperature between 50 ℃-64 ℃, adds in about 2 hours; 64 ℃ of insulation reaction 1.5 hours, finish following reaction:
Na
2SO
3+2NaHCO
3+C
7H
7ClO
2S
→2CO
2+H
2O+NaCl+Na
2SO
4+C
7H
7NaO
2S；
Drop into the gac of metering, insulation decolouring 50-60 minute, pump around circuit is filtered while hot, after backflow mother liquor to be recycled is as clear as crystal, enters the methylation reaction still, and is standby;
B. synthetic to methylsulfonyl toluene:
From step a methyl-sulfinic acid sodium salt solution is entered the methylation reaction still after, start stirring, be warming up to 60 ℃, connect vacuum system, the still internal pressure is reduced to-0.07Mpa after, close vacuum valve; Begin to feed monochloro methane, the still internal pressure constantly rises, in 10-15 divides clock time, the still internal pressure is raised to 0.2Mpa, and 85 ℃-90 ℃ of controlled temperature are between the pressure 0.20Mpa-0.25Mpa under the condition, continue to feed monochloro methane, the time that methylates, it was reaction end that the material in the still no longer absorbs gas, finishes following reaction between 18-19 hour:
C
7H
7SO
2Na+CH
3Cl→C
8H
10SO
2+NaCl；
C. regulate pH, cooling, discharging:
After methylation reaction finished, the pH of material under 80 ℃ of-85 ℃ of temperature, with alkali lye adjusting pH=9-10 and after stablizing, when being cooled to 50 ℃ with the interlayer recirculated cooling water, directly added cold water in reactor between 7-8, and temperature of charge is reduced to 40 ℃, and is to be filtered;
D. filter, dewater, dry:
40 ℃ material from step c is put into filter cylinder, filters; Filter cake is washed with water to pH=7.0, centrifuge dehydration, oven dry;
E. quality test, qualified back packing, warehouse-in.
3. according to the preparation method to methylsulfonyl toluene of claim 1, it is characterized in that step b. synthetic to methylsulfonyl toluene, technological process is as follows:
From step a methyl-sulfinic acid sodium salt solution is entered the methylation reaction still after, start stirring, be warming up to 60 ℃, connect vacuum system, the still internal pressure is reduced to-0.07Mpa after, close vacuum valve, begin to feed monochloro methane, the still internal pressure constantly rises, after the still internal pressure is raised to 0.20Mpa, and 86 ℃-88 ℃ of controlled temperature, under the pressure 0.28Mpa condition, continue to feed monochloro methane, the time that methylates, it was reaction end that the material in the still no longer absorbs gas between 18-19 hour.Finish following reaction:
C
7H
7SO
2Na+CH
3Cl→C
8H
10SO
2+NaCl。
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| CN200910018412A CN101659635B (en) | 2009-09-15 | 2009-09-15 | Preparation method of methyl p-tolyl sulfone |
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|---|---|---|---|
| CN200910018412A CN101659635B (en) | 2009-09-15 | 2009-09-15 | Preparation method of methyl p-tolyl sulfone |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101786973A (en) * | 2010-03-11 | 2010-07-28 | 嘉兴学院 | Synthesizing process of 4-methyl sodium benzene sulphinate |
| CN102363604A (en) * | 2011-09-28 | 2012-02-29 | 浙江嘉化能源化工股份有限公司 | Industrialized production method for methyl p-tolyl sulfone |
| CN102432509A (en) * | 2011-11-09 | 2012-05-02 | 嘉兴学院 | Method for preparing 4-methylsulfonyl toluene |
| CN102924347A (en) * | 2012-11-21 | 2013-02-13 | 徐州宇家化工科技有限公司 | Preparation method of phenyl methyl sulphone derivatives |
| CN106432008A (en) * | 2016-09-18 | 2017-02-22 | 沈根荣 | Methyl p-tolyl sulfone and preparation method |
| CN107089935A (en) * | 2017-05-23 | 2017-08-25 | 淮海工学院 | A kind of preparation method to methylsulfonyltoluene |
| CN108658730A (en) * | 2018-05-11 | 2018-10-16 | 常州大学 | A kind of preparation method of p-fluorophenol |
| CN110963948A (en) * | 2019-12-27 | 2020-04-07 | 山东天信化工有限公司 | Intermittent preparation method of 1-methyl-4-methylsulfonylbenzene |
| CN111039833A (en) * | 2019-12-27 | 2020-04-21 | 山东天信化工有限公司 | Continuous preparation method of 1-methyl-4-methylsulfonylbenzene |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4235155A1 (en) * | 1992-10-19 | 1994-04-21 | Basf Ag | Process for the preparation of methylsulfonylbenzoic acids |
| CN101434566A (en) * | 2008-12-04 | 2009-05-20 | 安吉豪森药业有限公司 | Production process of methyl p-tolyl sulfone |
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2009
- 2009-09-15 CN CN200910018412A patent/CN101659635B/en not_active Expired - Fee Related
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101786973A (en) * | 2010-03-11 | 2010-07-28 | 嘉兴学院 | Synthesizing process of 4-methyl sodium benzene sulphinate |
| CN101786973B (en) * | 2010-03-11 | 2013-01-16 | 嘉兴学院 | Synthesizing process of 4-methyl sodium benzene sulphinate |
| CN102363604A (en) * | 2011-09-28 | 2012-02-29 | 浙江嘉化能源化工股份有限公司 | Industrialized production method for methyl p-tolyl sulfone |
| CN102363604B (en) * | 2011-09-28 | 2013-10-30 | 浙江嘉化能源化工股份有限公司 | Industrialized production method for methyl p-tolyl sulfone |
| CN102432509A (en) * | 2011-11-09 | 2012-05-02 | 嘉兴学院 | Method for preparing 4-methylsulfonyl toluene |
| CN102924347A (en) * | 2012-11-21 | 2013-02-13 | 徐州宇家化工科技有限公司 | Preparation method of phenyl methyl sulphone derivatives |
| CN106432008A (en) * | 2016-09-18 | 2017-02-22 | 沈根荣 | Methyl p-tolyl sulfone and preparation method |
| CN107089935A (en) * | 2017-05-23 | 2017-08-25 | 淮海工学院 | A kind of preparation method to methylsulfonyltoluene |
| CN108658730A (en) * | 2018-05-11 | 2018-10-16 | 常州大学 | A kind of preparation method of p-fluorophenol |
| CN110963948A (en) * | 2019-12-27 | 2020-04-07 | 山东天信化工有限公司 | Intermittent preparation method of 1-methyl-4-methylsulfonylbenzene |
| CN111039833A (en) * | 2019-12-27 | 2020-04-21 | 山东天信化工有限公司 | Continuous preparation method of 1-methyl-4-methylsulfonylbenzene |
| CN111039833B (en) * | 2019-12-27 | 2021-07-13 | 山东天信化工有限公司 | Continuous preparation method of 1-methyl-4-methylsulfonylbenzene |
| CN110963948B (en) * | 2019-12-27 | 2022-04-15 | 山东天信化工有限公司 | Intermittent preparation method of 1-methyl-4-methylsulfonylbenzene |
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