CN102977042B - Preparation method of 1-methylbenzotriazole - Google Patents
Preparation method of 1-methylbenzotriazole Download PDFInfo
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- CN102977042B CN102977042B CN201210549763.2A CN201210549763A CN102977042B CN 102977042 B CN102977042 B CN 102977042B CN 201210549763 A CN201210549763 A CN 201210549763A CN 102977042 B CN102977042 B CN 102977042B
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- Prior art keywords
- tolyltriazole
- benzotriazole
- salt
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- underpressure distillation
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- 238000002360 preparation method Methods 0.000 title claims abstract description 9
- HXQHRUJXQJEGER-UHFFFAOYSA-N 1-methylbenzotriazole Chemical compound C1=CC=C2N(C)N=NC2=C1 HXQHRUJXQJEGER-UHFFFAOYSA-N 0.000 title abstract 5
- QRUDEWIWKLJBPS-UHFFFAOYSA-N benzotriazole Chemical compound C1=CC=C2N[N][N]C2=C1 QRUDEWIWKLJBPS-UHFFFAOYSA-N 0.000 claims abstract description 26
- 239000012964 benzotriazole Substances 0.000 claims abstract description 26
- 150000001565 benzotriazoles Chemical class 0.000 claims abstract description 17
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 claims abstract description 11
- 239000003513 alkali Substances 0.000 claims abstract description 8
- 238000000034 method Methods 0.000 claims abstract description 8
- 239000000203 mixture Substances 0.000 claims abstract description 6
- IEJIGPNLZYLLBP-UHFFFAOYSA-N dimethyl carbonate Chemical compound COC(=O)OC IEJIGPNLZYLLBP-UHFFFAOYSA-N 0.000 claims abstract description 5
- 239000007810 chemical reaction solvent Substances 0.000 claims abstract description 3
- NYKWVBSQRTXBCD-UHFFFAOYSA-N 1-(2-methylphenyl)triazole Chemical compound CC1=CC=CC=C1N1N=NC=C1 NYKWVBSQRTXBCD-UHFFFAOYSA-N 0.000 claims description 46
- UCFUJBVZSWTHEG-UHFFFAOYSA-N 4-(2-methylphenyl)-2h-triazole Chemical compound CC1=CC=CC=C1C1=CNN=N1 UCFUJBVZSWTHEG-UHFFFAOYSA-N 0.000 claims description 32
- 238000004821 distillation Methods 0.000 claims description 24
- 238000006243 chemical reaction Methods 0.000 claims description 20
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 16
- 239000000706 filtrate Substances 0.000 claims description 10
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 9
- CXHHBNMLPJOKQD-UHFFFAOYSA-M methyl carbonate Chemical compound COC([O-])=O CXHHBNMLPJOKQD-UHFFFAOYSA-M 0.000 claims description 8
- 239000012074 organic phase Substances 0.000 claims description 8
- 238000001953 recrystallisation Methods 0.000 claims description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 8
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 claims description 6
- 238000001035 drying Methods 0.000 claims description 6
- 150000003839 salts Chemical class 0.000 claims description 6
- 238000013517 stratification Methods 0.000 claims description 6
- 239000013078 crystal Substances 0.000 claims description 5
- LPNYRYFBWFDTMA-UHFFFAOYSA-N potassium tert-butoxide Chemical compound [K+].CC(C)(C)[O-] LPNYRYFBWFDTMA-UHFFFAOYSA-N 0.000 claims description 4
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Substances [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 claims description 3
- 235000015320 potassium carbonate Nutrition 0.000 claims description 3
- 238000001914 filtration Methods 0.000 claims description 2
- 239000011541 reaction mixture Substances 0.000 claims description 2
- 230000003381 solubilizing effect Effects 0.000 claims description 2
- 239000002904 solvent Substances 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 abstract description 9
- 238000005292 vacuum distillation Methods 0.000 abstract description 5
- 238000003912 environmental pollution Methods 0.000 abstract description 3
- PWORFEDVDWBHSJ-UHFFFAOYSA-N 2-methylbenzotriazole Chemical compound C1=CC=CC2=NN(C)N=C21 PWORFEDVDWBHSJ-UHFFFAOYSA-N 0.000 abstract 2
- 238000009776 industrial production Methods 0.000 abstract 1
- 238000004817 gas chromatography Methods 0.000 description 13
- 238000003756 stirring Methods 0.000 description 12
- 238000011084 recovery Methods 0.000 description 9
- 239000000047 product Substances 0.000 description 7
- 238000010792 warming Methods 0.000 description 5
- 239000003153 chemical reaction reagent Substances 0.000 description 4
- 238000004090 dissolution Methods 0.000 description 4
- INQOMBQAUSQDDS-UHFFFAOYSA-N iodomethane Chemical compound IC INQOMBQAUSQDDS-UHFFFAOYSA-N 0.000 description 4
- JZMJDSHXVKJFKW-UHFFFAOYSA-M methyl sulfate(1-) Chemical compound COS([O-])(=O)=O JZMJDSHXVKJFKW-UHFFFAOYSA-M 0.000 description 4
- 238000010992 reflux Methods 0.000 description 4
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- 239000012043 crude product Substances 0.000 description 3
- 230000001035 methylating effect Effects 0.000 description 3
- 239000012046 mixed solvent Substances 0.000 description 3
- ATHHXGZTWNVVOU-UHFFFAOYSA-N N-methylformamide Chemical compound CNC=O ATHHXGZTWNVVOU-UHFFFAOYSA-N 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000004440 column chromatography Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000011017 operating method Methods 0.000 description 2
- 239000003960 organic solvent Substances 0.000 description 2
- 239000012071 phase Substances 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 238000004611 spectroscopical analysis Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- KWYHDKDOAIKMQN-UHFFFAOYSA-N N,N,N',N'-tetramethylethylenediamine Chemical compound CN(C)CCN(C)C KWYHDKDOAIKMQN-UHFFFAOYSA-N 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 230000002152 alkylating effect Effects 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- FJDQFPXHSGXQBY-UHFFFAOYSA-L caesium carbonate Chemical compound [Cs+].[Cs+].[O-]C([O-])=O FJDQFPXHSGXQBY-UHFFFAOYSA-L 0.000 description 1
- 229910000024 caesium carbonate Inorganic materials 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000000383 hazardous chemical Substances 0.000 description 1
- 231100000086 high toxicity Toxicity 0.000 description 1
- 239000003112 inhibitor Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 239000000741 silica gel Substances 0.000 description 1
- 229910002027 silica gel Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
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- Preventing Corrosion Or Incrustation Of Metals (AREA)
- Heterocyclic Carbon Compounds Containing A Hetero Ring Having Nitrogen And Oxygen As The Only Ring Hetero Atoms (AREA)
Abstract
The invention relates to a preparation method of 1-methylbenzotriazole, which comprises the following steps: by using N,N-dimethylformamide as a reaction solvent, reacting benzotriazole with alkali to form a benzotriazole salt; reacting the benzotriazole salt with dimethyl carbonate to obtain a 1-methylbenzotriazole/2-methylbenzotriazole mixture; and carrying out vacuum distillation to separate 1-methylbenzotriazole from 2-methylbenzotriazole, thereby finally obtaining the 1-methylbenzotriazole. The method is simple to operate, has the advantages of low production cost and small environmental pollution, and is suitable for industrial production.
Description
Technical field:
The present invention relates to organic chemistry filed, particularly a kind of preparation method of 1-tolyltriazole.
Background technology:
1-tolyltriazole is widely used in the fields such as the anti-blushing agent of the clean-out system of metallic surface, metal inhibitor, metal and alloy thereof, is also the important intermediate of other benzotriazole derivative of preparation.The technology of existing synthesis 1-tolyltriazole is mainly with methyl-sulfate [J.Iran.Chem.Soc., 2007,4 (3), 271-278; J.Mater.Chem., 2003,13,2451 – 2456] or methyl iodide [Recl.Trv.Chim.Pays-Bas, 1991,110 (9), 369-373; J.Chem.Res., 2004,5,344-346] make methylating reagent, but methyl-sulfate is high toxicity compound, methyl iodide is then expensive hazardous substance, and both are all unfavorable for suitability for industrialized production.[the Synthetic Communications such as Sheng-Yin Zhao, 2012, 42:128 – 135] etc. report with the method for Study of Dimethyl Carbonate as Methylating Reagent synthesis 1-tolyltriazole, this method need use N, N, N, N-Tetramethyl Ethylene Diamine makes catalyzer, the product obtained is the mixture of 1-tolyltriazole and 2-tolyltriazole, both ratios are about 1.5:1, the selectivity of reaction is poor, and this paper does not provide corresponding purification process, concrete product yield data are not provided yet, great reference value is not had to the suitability for industrialized production of 1-tolyltriazole.
The alkylating reagents such as methyl-sulfate, methyl iodide, methylcarbonate and benzotriazole react, what obtain is all the mixture of 1-tolyltriazole and 2-tolyltriazole, and the method being separated 1-tolyltriazole and 2-tolyltriazole in prior art mainly contains column chromatography and two kinds, recrystallization.Although column chromatography for separation can obtain pure 1-tolyltriazole and 2-tolyltriazole, operating procedure is complicated, and fractional dose is few, and needs a large amount of organic solvents and silica gel, and separation costs is high, environmental pollution is large, is unsuitable for suitability for industrialized production; Recrystallization is separated can obtain pure 1-tolyltriazole, and operating procedure is simple, but can not get pure 2-tolyltriazole, and the yield of 1-tolyltriazole is low, is also unsuitable for suitability for industrialized production.
Summary of the invention
The technical problem to be solved in the present invention be to provide a kind of simple to operate, production cost is low, environmental pollution is little, be suitable for the preparation method of the 1-tolyltriazole of suitability for industrialized production.
For solving this technical problem, the technical solution used in the present invention is:
The preparation method of 1-tolyltriazole, with N, dinethylformamide (DMF) is reaction solvent, benzotriazole salt is formed by benzotriazole and alkali reaction, the benzotriazole salt obtained obtains the mixture of 1-tolyltriazole and 2-tolyltriazole again with dimethyl carbonate, be then separated by the method for underpressure distillation and obtain 1-tolyltriazole and 2-tolyltriazole.
Reaction equation of the present invention is as follows:
Concrete operation step of the present invention:
1, under stirring at room temperature, benzotriazole is dissolved into N, (benzotriazole and solvent N in dinethylformamide, the mass ratio of dinethylformamide is 1:2.3 ~ 2.8), then add appropriate alkali (mol ratio of benzotriazole and alkali is 1:1.0 ~ 1.1, reacts to benzotriazole and changes benzotriazole salt in batches.Be warming up to 90 ~ 100 DEG C, (mol ratio of benzotriazole and methylcarbonate is 1:1.3 ~ 1.75 to drip appropriate methylcarbonate,), isothermal reaction to benzotriazole salt participates in reaction completely, obtains the mixture of 1-tolyltriazole and 2-tolyltriazole.
2, being separated of 1-tolyltriazole and 2-tolyltriazole, purifying process carry out as follows: 1), by reaction mixture carry out underpressure distillation, collect the fraction of 58 ~ 68 DEG C (50KPa).Reclaim DMF; 2), distillation after residue in add appropriate water (mass ratio of benzotriazole and water is 1:2.3 ~ 2.7), the salt formed in solubilizing reaction process, stratification, separates organic phase; 3), organic phase anhydrous sodium sulfate drying, filtration, filtrate carries out underpressure distillation again, collects the fraction of 137 ~ 145 DEG C (50KPa), obtains 2-tolyltriazole; 4) ethanol of the residue after underpressure distillation/sherwood oil recrystallization, obtains 1-tolyltriazole white crystal.
This preparation method alkali used can be one or more in potassium tert.-butoxide, salt of wormwood, cesium carbonate, potassium hydroxide, sodium hydroxide.
Compared with prior art:
1, the present invention is with Study of Dimethyl Carbonate as Methylating Reagent, reacts lower than the more environmental protection of methyl-sulfate, methyl iodide, cost;
2, be separated 2-tolyltriazole and 1-tolyltriazole by the method for underpressure distillation, both can obtain pure 1-tolyltriazole, and also can obtain purer 2-tolyltriazole, both yields are all higher.In addition, reduced pressure distillation process is simple, without the need to using other organic solvent, production cost is low, is suitable for large batch of suitability for industrialized production.
Embodiment
Illustrate substance of the present invention and significant advantage further below by embodiment, but the present invention is absolutely not only confined to embodiment.
Embodiment 1: by 119g(1mol) benzotriazole, 275g N, dinethylformamide joins in three mouthfuls of round-bottomed flasks of 1000mL, stirring at room temperature, add 44.0g(1.1mol after benzotriazole dissolves completely in batches) sodium hydroxide, stirring at room temperature reaction changes into benzotriazole salt (tlc tracking) to benzotriazole.Be warming up to 90 DEG C, under stirring, drip 144g(1.6mol) methylcarbonate, isothermal reaction to benzotriazole salt participates in reacting (tlc tracking) completely.Room temperature cools, and changes reflux into vacuum distillation apparatus, collects the fraction of 58 ~ 68 DEG C (50KPa), and reclaim and obtain N, N-METHYLFORMAMIDE 256g, the rate of recovery is 93%.The salt formed in 275g water dissolution reaction process is added in underpressure distillation residue, stratification, separate organic phase, with anhydrous sodium sulfate drying, filter, in filtrate, the ratio of 1-tolyltriazole and 2-tolyltriazole is 63.0:37.0(gas chromatography determination), filtrate carries out underpressure distillation again, collect the fraction of 137 ~ 145 DEG C (50KPa), obtain 2-tolyltriazole 37.1g(gas chromatography determination, content 97.1%, wherein 2.9% is 1-tolyltriazole), thick yield is 27.9%; Resistates after underpressure distillation is 1-tolyltriazole crude product, heavy 90.4g(gas chromatography determination, content 89.5%, and wherein 10.5% is 2-tolyltriazole); Crude product ethanol and sherwood oil mixed solvent recrystallization (ethanol: sherwood oil=1:80, volume ratio), obtain 1-tolyltriazole white crystal 70.8g(gas chromatography determination, content 100%), clean yield is 53.2%.The total recovery of 1-tolyltriazole and 2-tolyltriazole is 95.8%.
Embodiment 2: by 119g(1mol) benzotriazole, 300g N, dinethylformamide joins in three mouthfuls of round-bottomed flasks of 1000mL, after stirring at room temperature to benzotriazole dissolves completely, add 112.0g(1mol in batches) potassium tert.-butoxide, reacts to benzotriazole and changes into benzotriazole salt (tlc tracking).Be warming up to 100 DEG C, under stirring, drip 117.0g(1.3mol) methylcarbonate, isothermal reaction to benzotriazole salt participates in reacting (tlc tracking) completely.Room temperature cools, and changes reflux into vacuum distillation apparatus, collects the fraction of 58 ~ 68 DEG C (50KPa), and reclaim and obtain DMF 273g, the rate of recovery is 91%.The salt formed in 295g water dissolution reaction process is added in underpressure distillation residue, stratification, separate organic phase, with anhydrous sodium sulfate drying, filter, in filtrate, the ratio of 1-tolyltriazole and 2-tolyltriazole is 64.6:35.4(gas chromatography determination), filtrate carries out underpressure distillation again, collect the fraction of 137 ~ 145 DEG C (50KPa), obtain 2-tolyltriazole 48.5g(gas chromatography determination, content 88.8%, wherein 11.2% is 1-tolyltriazole), thick yield is 36.4%; Resistates after underpressure distillation is the crude product of 1-tolyltriazole, heavy 83.5g(gas chromatography determination, content 95.9%, and wherein 4.1% is 2-tolyltriazole); Thick product ethanol and sherwood oil mixed solvent recrystallization (ethanol: sherwood oil=1:80, volume ratio), obtain 1-tolyltriazole white crystal 78.8g(gas chromatography determination, content 100%), clean yield is 59.2%.The total recovery of 1-tolyltriazole and 2-tolyltriazole is 99.1%.
Embodiment 3: by 119g(1mol) benzotriazole, 300g N, dinethylformamide joins in three mouthfuls of round-bottomed flasks of 1000mL, after stirring at room temperature to benzotriazole dissolves completely, add 123.2g(1.1mol in batches) potassium tert.-butoxide, stirring reaction to benzotriazole changes into benzotriazole salt (tlc tracking).Be warming up to 95 DEG C, under stirring, drip 157.5g(1.75mol) methylcarbonate, isothermal reaction to benzotriazole salt participates in reacting (tlc tracking) completely.Room temperature cool, change reflux into vacuum distillation apparatus, collect 58 ~ 68 DEG C of 50KPa) fraction, recovery obtain DMF 276g, the rate of recovery is 92%.The salt formed in 300g water dissolution reaction process is added in underpressure distillation residue, stratification, separate organic phase, with anhydrous sodium sulfate drying, filter, in filtrate, the ratio of 1-tolyltriazole and 2-tolyltriazole is 64.4:35.6(gas chromatography determination), filtrate carries out underpressure distillation again, collect the fraction of 137 ~ 145 DEG C (50KPa), obtain 2-tolyltriazole 49.9g(gas phase spectrometry to measure, content 92.5%, wherein 7.5% is 1-tolyltriazole), thick yield is 37.5%; Resistates after underpressure distillation is the thick product of 1-tolyltriazole, and heavy 77.0g(gas phase spectrometry measures, content 99.2%, and wherein 0.8% is 2-tolyltriazole), product is purer, and without the need to recrystallization, yield is 57.4%.The total recovery of 1-tolyltriazole and 2-tolyltriazole is 95.3%.
Embodiment 4:119g(1mol) benzotriazole, 330g N, dinethylformamide joins in three mouthfuls of round-bottomed flasks of 1000mL, after stirring at room temperature to benzotriazole dissolves completely, add 138.2g (1mol) salt of wormwood, stirring reaction to benzotriazole changes into benzotriazole salt (tlc tracking) in batches.Be warming up to 100 DEG C, drip 144.0g (13mol) methylcarbonate under stirring, isothermal reaction to benzotriazole salt participates in reacting (tlc tracking) completely.Room temperature cools, and changes reflux into vacuum distillation apparatus, collects the fraction of 58 ~ 68 DEG C (50KPa), and reclaim and obtain DMF 304g, the rate of recovery is 92%.The salt formed in 320g water dissolution reaction process is added in underpressure distillation residue, stratification, separate organic phase, with anhydrous sodium sulfate drying, filter, in filtrate, the ratio of 1-tolyltriazole and 2-tolyltriazole is 66.2:33.8(gas chromatography determination), filtrate carries out underpressure distillation again, collect the fraction of 137 ~ 145 DEG C (50KMPa), obtain 2-tolyltriazole 47.9g(gas chromatography determination, content 89.0%, wherein 11.0% is 1-tolyltriazole), thick yield 36.0%; Resistates after underpressure distillation is the thick product of 1-tolyltriazole, heavy 82.8g(gas chromatography determination, content 95.4%, and wherein 4.6% is 2-tolyltriazole); Thick product ethanol and sherwood oil mixed solvent recrystallization (ethanol: sherwood oil=1:80, volume ratio), obtain 1-tolyltriazole white crystal 79.0g(gas chromatography determination, content 100%), clean yield is 59.3%.The total recovery of 1-tolyltriazole and 2-tolyltriazole is 98.2%.
Claims (1)
1. a preparation method for 1-tolyltriazole, is characterized in that comprising the following steps:
1) take DMF as reaction solvent, form benzotriazole salt by benzotriazole and alkali reaction; The mass ratio of benzotriazole and solvent DMF is 1:2.3 ~ 2.8; The mol ratio of benzotriazole and alkali is 1:1.0 ~ 1.1; Described alkali is the one in potassium tert.-butoxide, salt of wormwood, sodium hydroxide;
2) benzotriazole salt obtains the mixture of 1-tolyltriazole and 2-tolyltriazole again with dimethyl carbonate, and temperature of reaction is 90 ~ 100 DEG C; The mol ratio of benzotriazole and methylcarbonate is 1:1.3 ~ 1.75;
3) be then separated 1-tolyltriazole and 2-tolyltriazole by the method for underpressure distillation, finally obtain 1-tolyltriazole, the concrete steps being separated 1-tolyltriazole and 2-tolyltriazole are:
A, reaction mixture is carried out underpressure distillation, 50KPa collects the fraction of 58-68 DEG C, reclaims DMF;
Add appropriate water in residue after B, distillation, the mass ratio of benzotriazole and water is 1:2.3 ~ 2.7, the salt formed in solubilizing reaction process, and stratification, separates organic phase;
C, organic phase anhydrous sodium sulfate drying, filtration, filtrate carries out underpressure distillation again, and 50KPa collects the fraction of 137 ~ 145 DEG C, obtains 2-tolyltriazole;
Residue after D, underpressure distillation ethanol/sherwood oil recrystallization, obtains 1-tolyltriazole white crystal.
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| CN201210549763.2A CN102977042B (en) | 2012-12-17 | 2012-12-17 | Preparation method of 1-methylbenzotriazole |
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| CN201210549763.2A CN102977042B (en) | 2012-12-17 | 2012-12-17 | Preparation method of 1-methylbenzotriazole |
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