CN102875543B - 4-tertiary butyl-5-(1, 2, 4-triazole-1-base)-2-aminothiazole preparation method - Google Patents
4-tertiary butyl-5-(1, 2, 4-triazole-1-base)-2-aminothiazole preparation method Download PDFInfo
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- CN102875543B CN102875543B CN201210403050.5A CN201210403050A CN102875543B CN 102875543 B CN102875543 B CN 102875543B CN 201210403050 A CN201210403050 A CN 201210403050A CN 102875543 B CN102875543 B CN 102875543B
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- triazol
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- KIVDZERHEZTUGL-UHFFFAOYSA-N CC(C)(C)C(C([n]1ncnc1)Br)=O Chemical compound CC(C)(C)C(C([n]1ncnc1)Br)=O KIVDZERHEZTUGL-UHFFFAOYSA-N 0.000 description 2
- MXSSOYWZWKZZPI-UHFFFAOYSA-N CC(C)(C)c1c(-[n]2ncnc2)[s]c(/N=C/[AlH2])n1 Chemical compound CC(C)(C)c1c(-[n]2ncnc2)[s]c(/N=C/[AlH2])n1 MXSSOYWZWKZZPI-UHFFFAOYSA-N 0.000 description 1
- AIMXEFQHBLNRMX-UHFFFAOYSA-N CC(C)(C)c1c(-[n]2ncnc2)[s]c(N)n1 Chemical compound CC(C)(C)c1c(-[n]2ncnc2)[s]c(N)n1 AIMXEFQHBLNRMX-UHFFFAOYSA-N 0.000 description 1
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- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a 4-tertiary butyl-5-(1, 2, 4-triazole-1-base)-2-aminothiazole preparation method. The 4-tertiary butyl-5-(1, 2, 4-triazole-1-base)-2-aminothiazole preparation method includes generating 3, 3-dimethyl-1-(1,2,4-triazole-1-base)-1-bromine-2-butanone by oxidizing hydrobromic acid by hydrogen peroxide or bromizing 3, 3-dimethyl-1-(1, 2, 4-triazole-1-base)-2-butanone by hydrobromide; bromizing the 3, 3-dimethyl-1-(1, 2, 4-triazole-1-base)-2-butanone by a side product, namely hydrobromic acid via hydrogen peroxide; subjecting the generated 3, 3-dimethyl-1-(1,2,4-triazole-1-base)-1-bromine-2-butanone to react with thiourea to generate 4-tertiary butyl-5-(1, 2, 4-triazole-1-base)-2-aminothiazole, recovering a side product, namely hydrobromide MBr, to acidize, oxidizing and bromizing the 3, 3-dimethyl-1-(1, 2, 4-triazole-1-base)-2-butanone by hydrogen peroxide to prepare the 3, 3-dimethyl-1-(1, 2, 4-triazole-1-base)-1-bromine-2-butanone. In the synthesis process, the bromine is sufficiently recycled.
Description
Technical field
The present invention relates to the preparation method of compound, the specifically 4-tertiary butyl-5-(1,2,4-triazol-1-yl) preparation method of-thiazolamine.
Background technology
[the ZL200910043920.0 such as Hu Aixi; CN102057918; CN201210052546.2] tertiary butyl-5-(1 through 4-described, 2,4-triazol-1-yl)-thiazolamine prepares the 4-tertiary butyl-5-(1,2,4-triazol-1-yl)-2-benzyl imino thiazole and the 4-tertiary butyl-5-(1,2,4-triazol-1-yl)-2-virtue aminothiazole, and studied its fungicidal activity, weeding activity and antitumour activity.
The 4-tertiary butyl-5-(1,2,4-triazol-1-yl)-thiazolamine is by 3,3-dimethyl-1-(1,2,4-triazol-1-yl)-2-butanone with etc. mole bromine react and make 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the bromo-2-butanone of-1-, cyclization neutralization makes [organic chemistry, 2010,30 (6): 923-927 again; Structural chemistry, 2010,29(11): 1680-1683], preparation feedback is as follows:
3,3-dimethyl-1-(1,2,4-triazol-1-yl)-2-butanone prepares the 4-tertiary butyl-5-(1 through above-mentioned technique, 2,4-triazol-1-yl) total recovery of-thiazolamine is 60.3% [with 3,3-dimethyl-1-(1,2,4-triazol-1-yl)-2-butanone meter, (70.5% × 85.5%=60.3%), organic chemistry, 2010,30 (6): 923-927]; The utilization ratio of bromo element is less than 36%.
Summary of the invention
The object of the present invention is to provide the 4-tertiary butyl-5-(1 shown in chemical structural formula I, 2,4-triazol-1-yl) preparation method of-thiazolamine:
The object of the present invention is to provide the 4-tertiary butyl-5-(1,2,4-triazol-1-yl) preparation method of-thiazolamine: the concrete preparation that it is characterized in that it is undertaken by (1) or (2) working method:
(1) adopt hydrogen peroxide oxidation Hydrogen bromide or hydrobromate (under sulfuric acid existence) or reclaim hydrobromate (under sulfuric acid existence) bromination 3,3-dimethyl-1-(1,2,4-triazol-1-yl)-2-butanone generation 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the bromo-2-butanone of-1-, byproduct hydrobromic acid is through hydrogen peroxide oxidation bromination 3,3-dimethyl-1-(1,2,4-triazol-1-yl)-2-butanone; 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the bromo-2-butanone of-1-reacts with thiocarbamide and makes the Hydrogen bromide 4-tertiary butyl-5-(1,2,4-triazol-1-yl)-thiazolamine; The Hydrogen bromide 4-tertiary butyl-5-(1,2,4-triazol-1-yl)-thiazolamine reacts with acid binding agent and generates the 4-tertiary butyl-5-(1,2,4-triazol-1-yl)-thiazolamine and byproduct hydrobromic acid salt MBr; Reclaim MBr through acidifying, hydrogen peroxide oxidation bromination 3,3-dimethyl-1-(1,2,4-triazol-1-yl)-2-butanone prepares 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the bromo-2-butanone of-1-; The abundant recycle of bromine in synthesis technique; Preparation feedback is as follows:
Acid binding agent is selected from: sodium carbonate, salt of wormwood, sodium bicarbonate, saleratus, sodium hydroxide, potassium hydroxide, sodium acetate or potassium acetate; Hydrobromate MBr is selected from: Sodium Bromide or Potassium Bromide.
(2) hydrobromate (under the sulfuric acid existence) bromination 3 that adopts hydrogen peroxide oxidation Hydrogen bromide or hydrobromate (under sulfuric acid existence) or reclaim, 3-dimethyl-1-(1,2,4-triazol-1-yl)-2-butanone generation 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the bromo-2-butanone of-1-, byproduct hydrobromic acid is through hydrogen peroxide oxidation bromination 3,3-dimethyl-1-(1,2,4-triazol-1-yl)-2-butanone; Under acid binding agent exists, 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the bromo-2-butanone of-1-reacts with thiocarbamide and makes the 4-tertiary butyl-5-(1,2,4-triazol-1-yl)-thiazolamine and byproduct hydrobromic acid salt MBr; Reclaim MBr through acidifying, hydrogen peroxide oxidation bromination 3,3-dimethyl-1-(1,2,4-triazol-1-yl)-2-butanone prepares 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the bromo-2-butanone of-1-; The abundant recycle of bromine in synthesis technique; Preparation feedback is as follows:
Wherein, acid binding agent is selected from: sodium carbonate, salt of wormwood, sodium bicarbonate, saleratus, sodium hydroxide, potassium hydroxide, sodium acetate or potassium acetate; Hydrobromate MBr is selected from: Sodium Bromide or Potassium Bromide.
The object of the present invention is to provide 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the preparation method of-bromo-2-butanone of 1-, it is undertaken by reaction (1) or (2):
In reaction formula, hydrobromate MBr is selected from: Sodium Bromide or Potassium Bromide.
The object of the present invention is to provide the 4-tertiary butyl-5-(1,2,4-triazol-1-yl) preparation method of-thiazolamine.It is undertaken by reaction (3) or (4):
In reaction formula, acid binding agent is selected from: sodium carbonate, salt of wormwood, sodium bicarbonate, saleratus, sodium hydroxide, potassium hydroxide, sodium acetate or potassium acetate; Hydrobromate MBr is selected from: Sodium Bromide or Potassium Bromide.
The object of the present invention is to provide 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the preparation method of-bromo-2-butanone of 1-, it is characterized in that 3,3-dimethyl-1-(1,2,4-triazol-1-yl) feed ratio (mol ratio) of-2-butanone, Hydrogen bromide and hydrogen peroxide is 1.0: 1.0: 2.0 ~ 1.0: 1.2: 2.4.
The object of the present invention is to provide 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the preparation method of-bromo-2-butanone of 1-, it is characterized in that 3,3-dimethyl-1-(1,2,4-triazol-1-yl) feed ratio (mol ratio) of-2-butanone, hydrobromate, hydrogen peroxide and sulfuric acid is 1.0: 1.0: 2.0: 1.0 ~ 1.0: 1.2: 2.4: 1.1.
The present invention compared with prior art tool has the following advantages:
The present invention adopts hydrogen peroxide oxidation Hydrogen bromide bromination 3 first, 3-dimethyl-1-(1,2,4-triazol-1-yl)-2-butanone generation 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the bromo-2-butanone of-1-, bromination discharge byproduct hydrobromic acid through hydrogen peroxide oxidation bromination 3,3-dimethyl-1-(1,2,4-triazol-1-yl)-2-butanone; 3 of generation, 3-dimethyl-1-(1,2,4-triazol-1-yl) the bromo-2-butanone of-1-reacts with thiocarbamide and makes the 4-tertiary butyl-5-(1,2,4-triazol-1-yl)-thiazolamine, the bromide anion of by-product is through acidifying, hydrogen peroxide oxidation bromination 3,3-dimethyl-1-(1,2,4-triazol-1-yl)-2-butanone prepares 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the bromo-2-butanone of-1-; The abundant recycle of bromine in synthesis technique.
Adopt hydrogen peroxide oxidation Hydrogen bromide or oxid-reclamatiom hydrobromate MBr bromination 3,3-dimethyl-1-(1,2,4-triazol-1-yl) technique of-2-butanone, the utilization ratio of bromine is higher than 80%; Save or made full use of resource, prevented (controlling) environmental pollution.
Embodiment
Following examples are intended to illustrate the present invention instead of limitation of the invention further.
Embodiment 1
The 4-tertiary butyl-5-(1,2,4-triazol-1-yl) preparation of-thiazolamine
(1) 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the preparation of-bromo-2-butanone of 1-
0.02 mol 3,3-dimethyl-1-(1,2,4-triazol-1-yl)-2-butanone, 4 mL glacial acetic acids, 40 mL tetracol phenixin, 3.2 mL 40% Hydrogen bromides add in reaction flask, stirs at 65 DEG C, drips 4.6 mL 30% hydrogen peroxide, reaction 3.5h; Add 20 mL sodium bicarbonate aqueous solutions, be stirred to without bubble and emerge; Separate organic layer, dichloromethane extraction, merges organic layer, saturated sodium-chloride washing, anhydrous sodium sulfate drying, desolventizing obtains 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the bromo-2-butanone weak yellow liquid of-1-, yellow liquid product is directly used in next step reaction.
(2) the 4-tertiary butyl-5-(1,2,4-triazol-1-yl) preparation of-thiazolamine
Obtained in the previous step 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the bromo-2-butanone yellow liquid of-1-, 25 mL ethanol, 0.02 mol thiocarbamide, backflow 1.5h.The cooling solid of separating out, suction filtration; Solid is dissolved in 40 mL water, and 0.01 mol wet chemical regulates pH 7; Separate out white solid, suction filtration, the dry 3.74 g 4-tertiary butyl-5-(1,2 of obtaining, 4-triazol-1-yl)-thiazolamine, overall yield 83.9%[is with 3,3-dimethyl-1-(1,2,4-triazol-1-yl)-2-butanone meter, total recovery is far above former technique (70.5% × 85.5%=60.3%)]; 178～181 DEG C of fusing points,
1hNMR(400MHz, CDCl
3) δ: 1.11(s, 9H, 3 × CH
3), 4.38(s, 2H, NH
2), 8.06(s, 1H, C
2h
2n
33-H), 8.23 (s, 1H, C
2h
2n
35-H); Filtrate is reclaimed Potassium Bromide 1.87g, is directly used in the first step reaction of embodiment 2.
Embodiment 2
The 4-tertiary butyl-5-(1,2,4-triazol-1-yl) preparation of-thiazolamine
(1) 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the preparation of-bromo-2-butanone of 1-
0.02 mol 3,3-dimethyl-1-(1,2,4-triazol-1-yl) Potassium Bromide, the 6 mL water of-2-butanone, 4 mL glacial acetic acids, 40 mL tetracol phenixin, 0.021 mol Potassium Bromide or recovery, stir, add the 1.14 mL vitriol oils, at 65 DEG C, drip 4.6 mL 30% hydrogen peroxide, reaction 3 h; Add 20 mL sodium bicarbonate aqueous solutions, be stirred to without bubble and emerge, separate organic layer, dichloromethane extraction, merges organic layer, with saturated sodium-chloride washing, anhydrous sodium sulfate drying.Desolventizing obtains 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the bromo-2-butanone weak yellow liquid of-1-.Weak yellow liquid is directly used in next step reaction.
(2) the 4-tertiary butyl-5-(1,2,4-triazol-1-yl) preparation of-thiazolamine
Obtained in the previous step 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the bromo-2-butanone of-1-is dissolved in 25 mL ethanol, adds 0.02 mol thiocarbamide, backflow 1.5h.Cooling, separate out solid, suction filtration; Solid is dissolved in 40 mL water, adds 0.01 mol wet chemical to regulate pH 7; Separate out white solid, suction filtration, the dry 3.79 g 4-tertiary butyl-5-(1,2, the 4-triazol-1-yl of obtaining)-thiazolamine white solid.Two-step reaction overall yield 85.0%[is with 3,3-dimethyl-1-(1,2,4-triazol-1-yl)-2-butanone meter, total recovery is far above former technique (70.5% × 85.5%=60.3%)]; 178～181 DEG C of fusing points,
1hNMR(400MHz, CDCl
3) δ: 1.11(s, 9H, 3 × CH
3), 4.38(s, 2H, NH
2), 8.06(s, 1H, C
2h
2n
33-H), 8.23 (s, 1H, C
2h
2n
35-H).Filtrate is reclaimed Potassium Bromide 1.85g, is directly used in previous step reaction.
Embodiment 3
The 4-tertiary butyl-5-(1,2,4-triazol-1-yl) preparation of-thiazolamine
(1) 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the preparation of-bromo-2-butanone of 1-
0.02 mol 3,3-dimethyl-1-(1,2,4-triazol-1-yl) Sodium Bromide, the 6 mL water of-2-butanone, 4 mL glacial acetic acids, 40 mL tetracol phenixin, 0.022 mol Sodium Bromide or recovery, stir, add the 1.19 mL vitriol oils, drip 4.6 mL 30% hydrogen peroxide at 65 DEG C, reaction 2.5h; Add 20 mL sodium bicarbonate aqueous solutions, be stirred to without bubble and emerge; Separate organic layer, dichloromethane extraction, merges organic layer.Saturated sodium-chloride washing, anhydrous sodium sulfate drying.Desolventizing obtains 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the bromo-2-butanone weak yellow liquid of-1-; Weak yellow liquid is directly used in next step reaction.
(2) the 4-tertiary butyl-5-(1,2,4-triazol-1-yl) preparation of-thiazolamine
Obtained in the previous step 3,3-dimethyl-1-(1,2,4-triazol-1-yl) the bromo-2-butanone of-1-, 25 mL ethanol, 0.02 mol thiocarbamide, 1.5 h reflux; The cooling solid of separating out, suction filtration; Solid is dissolved in 40 mL water, and 0.02 mol sodium bicarbonate aqueous solution regulates pH 7; Separate out white solid, suction filtration, the dry 3.46 g 4-tertiary butyl-5-(1,2, the 4-triazol-1-yl of obtaining)-thiazolamine white solid.Two-step reaction overall yield 77.6%[is with 3,3-dimethyl-1-(1,2,4-triazol-1-yl)-2-butanone meter, total recovery is far above former technique (70.5% × 85.5%=60.3%)]; 178～181 DEG C of fusing points,
1hNMR(400MHz, CDCl
3) δ: 1.11(s, 9H, 3 × CH
3), 4.38(s, 2H, NH
2), 8.06(s, 1H, C
2h
2n
33-H), 8.23 (s, 1H, C
2h
2n
35-H); Filtrate is reclaimed Sodium Bromide 1.66g, is directly used in previous step reaction.
Claims (1)
1. the preparation method of the 4-tertiary butyl-5-shown in a chemical structural formula I (1,2,4-triazol-1-yl)-thiazolamine:
Its concrete preparation manipulation method is as follows:
The preparation of (1) 3,3-dimethyl-1-(1,2,4-triazol-1-yl)-bromo-2-butanone of 1-
0.02mol3,3-dimethyl-1-(1,2,4-triazol-1-yl) Potassium Bromide, the 6mL water of-2-butanone, 4mL glacial acetic acid, 40mL tetracol phenixin, 0.021mol Potassium Bromide or recovery, stir, add the 1.14mL vitriol oil, at 65 DEG C, drip 4.6mL30% hydrogen peroxide, reaction 3h; Add 20mL sodium bicarbonate aqueous solution, be stirred to without bubble and emerge, separate organic layer, dichloromethane extraction, merges organic layer, with saturated sodium-chloride washing, anhydrous sodium sulfate drying; Desolventizing obtains the bromo-2-butanone weak yellow liquid of 3,3-dimethyl-1-(1,2,4-triazol-1-yl)-1-; Weak yellow liquid is directly used in next step reaction;
(2) preparation of the 4-tertiary butyl-5-(1,2,4-triazol-1-yl)-thiazolamine
Obtained in the previous step 3, the bromo-2-butanone of 3-dimethyl-1-(1,2,4-triazol-1-yl)-1-is dissolved in 25mL ethanol, adds 0.02mol thiocarbamide, backflow 1.5h; Cooling, separate out solid, suction filtration; Solid is dissolved in 40mL water, adds 0.01mol wet chemical to regulate pH7; Separate out white solid, suction filtration, the dry 3.79g4-tertiary butyl-5-(1,2,4-the triazol-1-yl)-thiazolamine white solid that to obtain; Two-step reaction overall yield 85.0%; 178～181 DEG C of fusing points; Filtrate is reclaimed Potassium Bromide 1.85g, is directly used in previous step reaction.
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