CN103483249A - Synthetic method for 2, 3, 5, 6-tetraaminopyridine hydrochloride - Google Patents
Synthetic method for 2, 3, 5, 6-tetraaminopyridine hydrochloride Download PDFInfo
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- CN103483249A CN103483249A CN201210379399.XA CN201210379399A CN103483249A CN 103483249 A CN103483249 A CN 103483249A CN 201210379399 A CN201210379399 A CN 201210379399A CN 103483249 A CN103483249 A CN 103483249A
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- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D213/00—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members
- C07D213/02—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
- C07D213/04—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom
- C07D213/60—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D213/72—Nitrogen atoms
- C07D213/73—Unsubstituted amino or imino radicals
Abstract
The invention relates to a synthetic method for 2, 3, 5, 6-tetraaminopyridine hydrochloride. The method comprises: step 1, adding an initial raw material 2,6-diamino-3, 5-dinitro pyridine, a solvent, an alkali catalyst and a Pd/C catalyst into a high-pressure reaction vessel; step 2, performing a hydrogenation reaction on the initial raw material placed in the high-pressure reaction vessel; step 3, adding active carbon into the reaction product obtained in the step 2, filtering the mixed product under the condition of nitrogen to obtain a filtrate; step 4, adding a mixed solution of concentrated hydrochloric acid and tetrahydrofuran into the filtrate obtained in the step 3 to precipitate crystal, then standing at room temperature, filtering under the condition of nitrogen to obtain a filter cake; and step 5, performing vacuum drying on the filter cake obtained in the step 4 to obtain the finished product 2, 3, 5, 6-tetraaminopyridine hydrochloride. The synthetic method has the advantages of high synthetic finished product purity, high yield, short consumed time, low cost, small pollution and the like, and is applicable to industrialized production.
Description
Technical field
The present invention relates to a kind of synthetic method of organic synthesis intermediate, particularly a kind of 2,3,5, the synthetic method of 6-4-aminopyridine hydrochloride.
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Background technology
2,3,5,6-4-aminopyridine hydrochloride, because of its unique structure, is not only the organic intermediates such as important medicine, agricultural chemicals, dyestuff, can also be as synthetic high molecular functional monomer, rigidity speciality polymer monomer, especially as high-performance M5 fiber polymer monomer, 2,3,5,6-4-aminopyridine hydrochloride purity directly affects high molecular molecular weight, therefore improves 2,3, productive rate, the purity of 5,6-4-aminopyridine hydrochloride, realize that to it suitability for industrialized production is significant.
The structural formula of 2,3,5,6-4-aminopyridine hydrochloride is:
Existing 2,3,5, the synthetic method of 6-4-aminopyridine mainly contains normal pressure reduction method and high-pressure hydrogenation reduction method." a kind of 2,3,5, the preparation method of 6-4-aminopyridine " who proposes as Chinese patent application 200610030027.0, be under normal pressure with 2,6-diamino-3,5-di nitryl pyridine for raw material, the anhydrous formic acid ammonium is reductive agent, Pd/C is synthetic 2,3,5, the 6-4-aminopyridine of catalyzer.Although the method has short, productive rate of reaction times than advantages of higher, but the ammonium formiate high cost that the method is used, and after reaction finishes, treatment process complexity, products obtained therefrom 2,3,5,6-4-aminopyridine is easily oxidized, poor chemical stability, the environmental pollution degree is large simultaneously, is not suitable for suitability for industrialized production.
Daetze J.Sikkemax.Design, synthesis and properties of a novel rigid rod polymer, PIPD or ' M5`:high modulus and tenacity fibres with substantial compressive strength. Polymer Vol.39 No. 24 pp. 5981-5986. 1998, reported with 2, 6-diamino-3, the 5-di nitryl pyridine is raw material, in phosphoric acid solution, the high pressure hydrogen reduction, react more than 30 hour, the stability that obtains finished product is better, but the method reaction times is long, productive rate is low, big for environment pollution, be not suitable for suitability for industrialized production.
The deficiency that how to overcome above-mentioned prior art existence has become great difficult problem urgently to be resolved hurrily in the organic synthesis intermediate field.
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Summary of the invention
The object of the invention is to overcome the deficiencies in the prior art and provide a kind of 2,3,5, the synthetic method of 6-4-aminopyridine hydrochloride, the present invention not only has that synthetic finished product purity is high, productive rate is high, and have consuming time short, cost is low, pollute the advantages such as little, is suitable for suitability for industrialized production.
What according to the present invention, propose is a kind of 2,3,5, and the synthetic method of 6-4-aminopyridine hydrochloride, is characterized in that comprising the steps:
The first step, by starting raw material 2, 6-diamino-3, the 5-di nitryl pyridine, solvent, basic catalyst and Pd/C catalyzer join in autoclave, starting raw material proportioning wherein: with 2, 6-diamino-3, it is benchmark that the 5-di nitryl pyridine adds quality, solvent adds quality and 2, 6-diamino-3, it is 6～12:1 that the 5-di nitryl pyridine adds mass ratio, basic catalyst adds quality and 2, 6-diamino-3, it is 0.6～1:1 that the 5-di nitryl pyridine adds mass ratio, the Pd/C catalyzer adds quality and 2, 6-diamino-3, the 5-di nitryl pyridine adds mass ratio to be: 0.06～0.1:1, in the Pd/C catalyzer, the charge capacity of palladium is 5% or 10%,
Second step, adding hydrogen to pressure in the autoclave of the preset starting raw material of the first step is 0.5-1.5MPa, controlling temperature of reaction is 40-70 ℃, reaction times 1.5-3h;
The 3rd step, join gac in the reaction product that second step obtains, and stirred simultaneously, and gac add-on and 2,6-diamino-3,5-di nitryl pyridine mass ratio are 0.04～0.1:1, under condition of nitrogen gas, mix products filtered, and obtains filtrate;
The 4th step, join the mixing solutions of concentrated hydrochloric acid and tetrahydrofuran (THF) in the filtrate that the 3rd step obtains, and makes its crystallize out, then at room temperature under standing, condition of nitrogen gas, filters, and obtains filter cake;
The 5th step, the filter cake drying that the 4th step is obtained obtains the final flaxen target product 2,3,5 that is, 6-4-aminopyridine hydrochloride finished product.
The present invention further optimization scheme is: the mixture that the described solvent of the first step is distilled water, dehydrated alcohol or distilled water and dehydrated alcohol; Described basic catalyst is ammoniacal liquor or triethylamine, and wherein the mass percentage concentration of ammoniacal liquor is 20%～36%.The 4th step is described 2, and the mass ratio of the mixed solution of 6-diamino-3,5-di nitryl pyridine and concentrated hydrochloric acid and tetrahydrofuran (THF) is 1:6-12, and wherein the volume ratio of concentrated hydrochloric acid and tetrahydrofuran (THF) is 1:1; Described room temperature time of repose is 12～24h.The described drying of the 5th step is to carry out under vacuum condition, drying temperature 40-60 ℃, time of drying 12～24h.
The present invention compared with prior art its remarkable advantage is: the first, and the reaction conditions gentleness, temperature of reaction is only 40-70 ℃, and reaction pressure is only 0.5-1.5MPa, and the reaction times is only 1.5-3h.The second, react completely, products collection efficiency up to 90%-97%, purity up to 99%.The 3rd, product exists with the form of hydrochloride, and chemical stability is good, is applicable to long storage.The 4th, use the hydrogenating reduction technology, pollution-free, meet Green Chemistry industry, be applicable to suitability for industrialized production.The comprehensive comparison of the present invention and prior art refers to table 1.
Table 1: the present invention and prior art over-all properties contrast table look-up
The accompanying drawing explanation
Fig. 1 is of the present invention 2,3,5, the schematic flow sheet of 6-4-aminopyridine hydrochloride synthetic method.
Fig. 2 is of the present invention 2,3,5, the proton nmr spectra of 6-4-aminopyridine hydrochloride (
1hNMR) schematic diagram.
Fig. 3 is of the present invention 2,3,5, the carbon-13 nmr spectra of 6-4-aminopyridine hydrochloride (
13cNMR) schematic diagram.
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Embodiment
Below in conjunction with the drawings and specific embodiments, the present invention is described in further detail.
Reaction process of the present invention as shown in the formula:
Synthetic method of the present invention, starting raw material 2, the 6-diamino-3,5-di nitryl pyridine can be by Polymer, 39(24), 5981-5986,1988 disclosed methods prepare; Other raw materials are commercially available general chemical raw material.
The present invention, with the magnetic resonance detection finished product structure, detects finished product purity with high performance liquid chromatography (HPLC).
Embodiment 1:
The first step, by starting raw material 2, the ammoniacal liquor 300g that 6-diamino-3,5-di nitryl pyridine 500g, distilled water 1500g, dehydrated alcohol 1500g, massfraction are 36% and 5%Pd/C catalyzer 50g join in autoclave;
Second step, in the autoclave of the preset starting raw material of the first step, air three times in logical hydrogen exchange autoclave, then add hydrogen to pressure 0.5MPa, 70 ℃ of temperature of reaction, reaction times 3h;
The 3rd step, join gac 20g in the reaction product that second step obtains, and stirred simultaneously, under condition of nitrogen gas, mixture filtered, and obtains filtrate;
The 4th step, the mixing solutions that concentrated hydrochloric acid 1500g and tetrahydrofuran (THF) 1500g are formed joins in the filtrate that the 3rd step obtains, and makes its crystallize out, and then standing 24h at room temperature, filter under condition of nitrogen gas, obtains filter cake;
The 5th step, the filter cake that the 4th step is obtained, at vacuum, 60 ℃ of dry 12h of condition, obtains the final flaxen target product 2,3,5 that is, 6-4-aminopyridine hydrochloride finished product 627.2g, productive rate 93.6%, purity 99.4%(HPLC).
The detected result data of the finished product structure of this compound are as follows:
1HNMR（DMSO）：7.5032ppm（s，1?H）；
13CNMR（DMSO）：98.5231，132.5388，144.4997ppm。
From above-mentioned data, this compound structure is correct, is 2,3,5,6-4-aminopyridine hydrochloride.
Embodiment 2:
The first step, by starting raw material 2, the ammoniacal liquor 800g that 6-diamino-3,5-di nitryl pyridine 1000g, distilled water 4000g, dehydrated alcohol 4000g, massfraction are 26% and 10%Pd/C catalyzer 80g join in autoclave;
Second step, in the autoclave of the preset starting raw material of the first step, air three times in logical hydrogen exchange autoclave, then add hydrogen to pressure 1MPa, 55 ℃ of temperature of reaction, reaction times 2h;
The 3rd step, join gac 80g in the reaction product that second step obtains, and stirred simultaneously, under condition of nitrogen gas, mixture filtered, and obtains filtrate;
The 4th step, the mixing solutions that concentrated hydrochloric acid 4000g and tetrahydrofuran (THF) 4000g are formed joins in the filtrate that the 3rd step obtains, and makes its crystallize out, and then standing 18h at room temperature, filter under condition of nitrogen gas, obtains filter cake;
The 5th step, the filter cake that the 4th step is obtained, at vacuum, 50 ℃ of dry 18h of condition, obtains the final flaxen target product 2,3,5 that is, 6-4-aminopyridine hydrochloride finished product 1301.4g, productive rate 97.0%, purity 99.9%(HPLC).
Warp
1hNMR,
13cNMR detects, and its detected result data are identical with embodiment 1, and this compound structure is correct, is 2,3,5,6-4-aminopyridine hydrochloride.
Embodiment 3:
The first step, by starting raw material 2, the ammoniacal liquor 500g that 6-diamino-3,5-di nitryl pyridine 500g, distilled water 6000g, massfraction are 20% and 10%Pd/C catalyzer 30g join in autoclave;
Second step, in the autoclave of the preset starting raw material of the first step, air three times in logical hydrogen exchange autoclave, then add hydrogen to pressure 1.5MPa, 40 ℃ of temperature of reaction, reaction times 1.5h;
The 3rd step, join gac 50g in the reaction product that second step obtains, and stirred simultaneously, under condition of nitrogen gas, mixture filtered, and obtains filtrate;
The 4th step, join the mixing solutions of concentrated hydrochloric acid 3000g and tetrahydrofuran (THF) 3000g in the filtrate that the 3rd step obtains, and makes its crystallize out, and then standing 12h at room temperature, filter under condition of nitrogen gas, obtains filter cake;
The 5th step, the filter cake that the 4th step is obtained, at vacuum, 40 ℃ of dry 24h of condition, obtains the final flaxen target product 2,3,5 that is, 6-4-aminopyridine hydrochloride finished product 650.7g, productive rate 97.0%, purity 99.7%(HPLC).
Through 1HNMR, 13CNMR detects, and its detected result data are identical with embodiment 1, and this compound structure is correct, is 2,3,5,6-4-aminopyridine hydrochloride.
Embodiment 4:
The first step, by starting raw material 2,6-diamino-3,5-di nitryl pyridine 500g, dehydrated alcohol 5000g, triethylamine 500g and 5%Pd/C catalyzer 50g join in autoclave;
Second step, in the autoclave of the preset starting raw material of the first step, air three times in logical hydrogen exchange autoclave, then add hydrogen to pressure 1.5MPa, 70 ℃ of temperature of reaction, reaction times 3h;
The 3rd step, join gac 20g in the reaction product that second step obtains, and stirred simultaneously, under condition of nitrogen gas, mixture filtered, and obtains filtrate;
The 4th step, join the mixing solutions of concentrated hydrochloric acid 2500g and tetrahydrofuran (THF) 2500g in the filtrate that the 3rd step obtains, and makes its crystallize out, and then standing 24h at room temperature, filter under condition of nitrogen gas, obtains filter cake;
The 5th step, the filter cake that the 4th step is obtained, at vacuum, 60 ℃ of dry 12h of condition, obtains the final flaxen target product 2,3,5 that is, 6-4-aminopyridine hydrochloride finished product 623.2g, productive rate 92.9%, purity 99.2%(HPLC).
Through 1HNMR, 13CNMR detects, and its detected result data are identical with embodiment 1, and this compound structure is correct, is 2,3,5,6-4-aminopyridine hydrochloride.
Embodiment 5:
The first step, by starting raw material 2,6-diamino-3,5-di nitryl pyridine 1000g, distilled water 3000g, dehydrated alcohol 3000g, triethylamine 600g and 10%Pd/C catalyzer 60g join in autoclave;
Second step, in the autoclave of the preset starting raw material of the first step, air three times in logical hydrogen exchange autoclave, then add hydrogen to pressure 1MPa, 50 ℃ of temperature of reaction, reaction times 2h;
The 3rd step, join gac 60g in the reaction product that second step obtains, and stirred simultaneously, under condition of nitrogen gas, mixture filtered, and obtains filtrate;
The 4th step, join the mixing solutions of concentrated hydrochloric acid 3000g and tetrahydrofuran (THF) 3000g in the filtrate that the 3rd step obtains, and makes its crystallize out, and then standing 20h at room temperature, filter under condition of nitrogen gas, obtains filter cake;
The 5th step, the filter cake that the 4th step is obtained, at vacuum, 55 ℃ of dry 16h of condition, obtains the final flaxen target product 2,3,5 that is, 6-4-aminopyridine hydrochloride finished product 1290.7g, productive rate 96.2%, purity 99.6%(HPLC).
Through 1HNMR, 13CNMR detects, and its detected result data are identical with embodiment 1, and this compound structure is correct, is 2,3,5,6-4-aminopyridine hydrochloride.
Claims (6)
1. one kind 2,3,5, the synthetic method of 6-4-aminopyridine hydrochloride, is characterized in that comprising the steps:
The first step, by starting raw material 2, 6-diamino-3, the 5-di nitryl pyridine, solvent, basic catalyst and Pd/C catalyzer join in autoclave, starting raw material proportioning wherein: with 2, 6-diamino-3, it is benchmark that the 5-di nitryl pyridine adds quality, solvent adds quality and 2, 6-diamino-3, it is 6～12:1 that the 5-di nitryl pyridine adds mass ratio, basic catalyst adds quality and 2, 6-diamino-3, it is 0.6～1:1 that the 5-di nitryl pyridine adds mass ratio, the Pd/C catalyzer adds quality and 2, 6-diamino-3, the 5-di nitryl pyridine adds mass ratio to be: 0.06～0.1:1, in the Pd/C catalyzer, the charge capacity of palladium is 5% or 10%,
Second step, adding hydrogen to pressure in the autoclave of the preset starting raw material of the first step is 0.5-1.5MPa, controlling temperature of reaction is 40-70 ℃, reaction times 1.5-3h;
The 3rd step, join gac in the reaction product that second step obtains, and stirred simultaneously, and gac add-on and 2,6-diamino-3,5-di nitryl pyridine mass ratio are 0.04～0.1:1, under condition of nitrogen gas, mix products filtered, and obtains filtrate;
The 4th step, join the mixing solutions of concentrated hydrochloric acid and tetrahydrofuran (THF) in the filtrate that the 3rd step obtains, and makes its crystallize out, then at room temperature under standing, condition of nitrogen gas, filters, and obtains filter cake;
The 5th step, the filter cake drying that the 4th step is obtained obtains the final flaxen target product 2,3,5 that is, 6-4-aminopyridine hydrochloride finished product.
2. synthetic method according to claim 1, is characterized in that the mixture that the described solvent of the first step is distilled water, dehydrated alcohol or distilled water and dehydrated alcohol.
3. synthetic method according to claim 1, is characterized in that the described basic catalyst of the first step is ammoniacal liquor or triethylamine, and wherein the mass percentage concentration of ammoniacal liquor is 20%～36%.
4. synthetic method according to claim 1, is characterized in that the 4th step is described 2, and the mass ratio of the mixed solution of 6-diamino-3,5-di nitryl pyridine and concentrated hydrochloric acid and tetrahydrofuran (THF) is 1:6-12, and wherein the volume ratio of concentrated hydrochloric acid and tetrahydrofuran (THF) is 1:1.
5. synthetic method according to claim 1, is characterized in that the described room temperature time of repose of the 4th step is 12～24h.
6. synthetic method according to claim 1, is characterized in that the described drying of the 5th step is to carry out under vacuum condition, drying temperature 40-60 ℃, time of drying 12～24h.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109761893A (en) * | 2018-06-14 | 2019-05-17 | 吉林师范大学 | The preparation method of 2,3,5,6- 4-aminopyridines |
| WO2023112605A1 (en) * | 2021-12-14 | 2023-06-22 | 本州化学工業株式会社 | Crystal of isomannide-bis(trimellitate anhydride), and method for producing same |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA1124717A (en) * | 1977-03-19 | 1982-06-01 | Robert J. Ife | 1,2,4-triazinones-5 |
| CH682562A5 (en) * | 1991-12-02 | 1993-10-15 | Lonza Ag | 3-Amino-5-ethyl-6 -methyl-2-pyridone prepn. - from acrylonitrile in 4 stages via new 5-ethyl-6-methyl-2-pyridone, used as intermediate for anti-AIDS agents |
| CN101289419A (en) * | 2008-06-06 | 2008-10-22 | 哈尔滨工业大学 | Process for preparing 2,3,5,6-tetraminopyridine hydrochloride |
-
2012
- 2012-10-09 CN CN201210379399.XA patent/CN103483249A/en not_active Withdrawn
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA1124717A (en) * | 1977-03-19 | 1982-06-01 | Robert J. Ife | 1,2,4-triazinones-5 |
| CH682562A5 (en) * | 1991-12-02 | 1993-10-15 | Lonza Ag | 3-Amino-5-ethyl-6 -methyl-2-pyridone prepn. - from acrylonitrile in 4 stages via new 5-ethyl-6-methyl-2-pyridone, used as intermediate for anti-AIDS agents |
| CN101289419A (en) * | 2008-06-06 | 2008-10-22 | 哈尔滨工业大学 | Process for preparing 2,3,5,6-tetraminopyridine hydrochloride |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109761893A (en) * | 2018-06-14 | 2019-05-17 | 吉林师范大学 | The preparation method of 2,3,5,6- 4-aminopyridines |
| WO2023112605A1 (en) * | 2021-12-14 | 2023-06-22 | 本州化学工業株式会社 | Crystal of isomannide-bis(trimellitate anhydride), and method for producing same |
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