CN1274688C - Synthesis method of 5-hydroxy methyl furazolidone - Google Patents
Synthesis method of 5-hydroxy methyl furazolidone Download PDFInfo
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- CN1274688C CN1274688C CN 03142152 CN03142152A CN1274688C CN 1274688 C CN1274688 C CN 1274688C CN 03142152 CN03142152 CN 03142152 CN 03142152 A CN03142152 A CN 03142152A CN 1274688 C CN1274688 C CN 1274688C
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Abstract
The present invention discloses a synthesis method of 5-hydroxy methyl-furazolidone. 1-chloroglycerine, hydrazine hydrate, sodium hydroxide, sodium methylate, dimethyl ester and 5-nitrofurfural diacetate are used as raw material for a reaction. The present invention is characterized in that the used hydrazine hydrate is water solution of hydrazine hydrate, wherein the concentration of the water solution of hydrazine hydrate is less than 100%. The present invention mainly solves the problems that hydrazine hydrate whose working concentration is 100% is required, and requirements for technical conditions are too high existing in a preparation method of 5-hydroxy methyl-furazolidone in the prior art. The present invention aims to provide a preparation method of 5-hydroxy methyl-furazolidone, which has the advantages that the preparation method is simple, the industrialization is easy, and the cost is almost equal to the cost of furazolidone. The present invention also solves the problem that lots of sodium chloride precipitates need processing in the preparation process of 5-hydroxy methyl-furazolidone in the prior art.
Description
Technical field
The present invention relates to a kind of synthetic method of 5-methylol-Nifurazolidone, the synthetic method of 5-methylol-Nifurazolidone that particularly a kind of processing condition are easy to realize belongs to the organic synthesis technology scope.
Background technology
5-methylol-Nifurazolidone (I), full name 3-(5-nitrofuran methene amido)-5-oxazolidone-(2), it is to increase a methylol groups on the Nifurazolidone basis; Nifurazolidone is a wide-spectrum bactericide, be used for the treatment of bacillary dysentery, enteron aisle and urinary tract infection, be used for animal drug and fodder additives for many years in a large number, especially culture fishery, because Nifurazolidone is water-soluble hardly, is difficult to and the feed uniform mixing, causes the animal-use drug amount big, residual quantity exceeds standard in the body, has forbidden that from the Ministry of Agriculture in 2002 Nifurazolidone is used for animal drug and fodder additives; 5-methylol-Nifurazolidone is compared with Nifurazolidone, and maximum characteristics are that the solvability in water increases, especially in hot water, the animal-use drug amount can correspondingly reduce like this, mix also evenly with feed, can not cause medication inequality between the animal, the also corresponding minimizing of the intravital residual quantity of animal; The molecular structural formula of 5-methylol-Nifurazolidone is by (the T of pharmaceuticals of U.S. Norwich
HEN
ORWICHP
HARMACALC
OMPANY) in nineteen fifty-five open (patent No. GB735136), synthetic method is: add the hundred-percent hydrazine hydrate of 43g sodium hydroxide and 250g earlier, be heated to 44 ℃, drip the 1-glycerin chlorohydrin of 110g, be incubated more than 35 minutes under 85-90 ℃ the temperature, progressively be heated to backflow, room temperature is crossed liquid after being incubated 30 minutes, excessive hydrazine hydrate steams with vacuum, the material that stays adds dehydrated alcohol, insoluble sodium-chlor sedimentation and filtration is removed, and ethanol filtrate adds sodium ethylate (sodium Metal 99.5 and dehydrated alcohol reaction), diethyl carbonate, back flow reaction can obtain 5-methylol-Nifurazolidone in 3 hours.Because present method used hydrazine hydrate in building-up process is the hydrazine hydrate of concentration 100%, make to adopt this legal system be equipped with the cost of 5-methylol-Nifurazolidone and processing condition require also too high since the restriction of above problem make 5-methylol-Nifurazolidone all fail all the time application widely.
Summary of the invention
Purpose of the present invention: mainly be that to solve need working concentration that the preparation method of 5-methylol-Nifurazolidone in the prior art exists be that 100% hydrazine hydrate and processing condition require too high problem, aim to provide a kind of simple, easily industrialization, cost and the much the same 5-methylol of Nifurazolidone-Nifurazolidone preparation method.
Above-mentioned purpose of the present invention mainly is achieved by following technical proposals:
Add concentration earlier and be equal to or less than 80% the hydrazine hydrate aqueous solution or the hydrazine hydrate of recovery, be heated to 80-90 ℃, drip the 1-glycerin chlorohydrin, progressively be warming up to 100-130 ℃ then, the insulation of backflow one hour arranged, hydro-oxidation sodium when being cooled to 40-45 ℃ afterwards, in the 100 ℃ of insulations 10 minutes that heat up, hydrazine hydrate is reclaimed in underpressure distillation subsequently, when being distilled to 110 ℃, to there not being liquid to steam, a large amount of sodium-chlor precipitations appears, cooling, precipitation do not need processing directly to enter next step
Reaction formula is as follows:
Or add earlier concentration and be less than or equal to 80% hydrazine hydrate aqueous solution, heat temperature raising to 90 ℃ drips Racemic glycidol, and controlled temperature is at 95-100 ℃, 100 ℃ are incubated 1 hour then, and hydrazine hydrate is reclaimed in underpressure distillation subsequently, is distilled to 110 ℃, when not having liquid to steam, cooling, reaction formula is as follows:
Add sodium methylate when treating that temperature is reduced to 70 ℃, stir, add dimethyl ester at 65 ℃, 68 ℃ of left and right sides back flow reaction 30 minutes reclaim methyl alcohol and methylcarbonate, and reaction formula is as follows:
Add water-soluble clear (water is as solvent) then, add hydrochloric acid, be heated to 65 ℃, add the 5-nitryl furfural ester diacetate, be heated to 84 ℃, be incubated 20 ℃, separate out yellow solid, be cooled to 40 ℃, suction filtration, washing, ethanol is washed, and gets product after the oven dry, and reaction formula is as follows:
Described 1-glycerin chlorohydrin can be by water and epoxy chloropropane with weight ratio 11: 12 at 104 ℃, under the pH value 3-4, be that catalyzer is synthetic with sulfuric acid, the 1-glycerin chlorohydrin yield of this law is higher, lower relatively than directly going to buy 1-glycerin chlorohydrin cost from the market, reaction formula is as follows:
The mol ratio of described hydrazine hydrate and 1-glycerin chlorohydrin is 1: 1.6-1: 4.8, and optimum value is 1: 3.2.
As preferably, described a large amount of sodium-chlor precipitation can directly enter next step reaction, need not to handle, and in terms of existing technologies, has reduced operation steps, provides cost savings.
As preferably, during described dimethyl carbonate with sodium methylate as catalyzer, with the mol ratio of 1-glycerin chlorohydrin be 0.133: 1-0.333: 1, optimum value is 0.199: 1.
Therefore, it is simple that the present invention has operational condition, and step is few, easily industrialization, cost and Nifurazolidone are similar, product yield height, the change of characteristics, particularly operational condition such as the purity height of product makes 5-methylol-Nifurazolidone can realize suitability for industrialized production and being applicable pharmaceutically.
Embodiment
Below by embodiment, technical scheme of the present invention is described in further detail.
Embodiment 1:
Add earlier 80% hydrazine hydrate aqueous solution 50g, heat temperature raising to 80 ℃ drips 1-glycerin chlorohydrin 27.5 grams, after adding, progressively be warming up to 120-125 ℃, backflow is arranged, reacted 1 hour, be cooled to 40-45 ℃ afterwards, hydro-oxidation sodium 10.5g is warming up to 100 ℃, is incubated 10 minutes, subsequently, hydrazine hydrate is reclaimed in underpressure distillation, is distilled to 110 ℃, vacuum 0.093Mpa to there not being liquid to steam, has a large amount of solid sodium chlorides to occur, need not to handle, cooling enters next step reaction;
When temperature is reduced to 70 ℃, add sodium methylate 9g, stir after 5 minutes, 65 ℃ add methylcarbonate 25ml, 68 ℃ of left and right sides back flow reaction 30 minutes reclaim methyl alcohol and methylcarbonate, add water-soluble clear (water as solvent) after the end, add hydrochloric acid (32%) 80ml, be heated to 65 ℃, add 5-nitryl furfural ester diacetate 26.5g, be heated to 84 ℃, be incubated 20 minutes, separate out yellow solid, be cooled to 40 ℃, suction filtration, washing, ethanol is washed, and gets product 25.8g after the oven dry, and recording fusing point is 240-242 ℃ (document is 241-243 ℃), the HPLC purity assay is 98.5%, and total recovery is 36.4%.
Embodiment 2:
Add earlier 20% hydrazine hydrate aqueous solution 200g, heat temperature raising to 80 ℃ drips 1-glycerin chlorohydrin 27.5 grams, after adding, install back receiving apparatus, progressively be warming up to more than 100 ℃, recovery part water rises to 120-125 ℃ to temperature, changes reflux into, reacted 1 hour, be cooled to 40-45 ℃ afterwards, hydro-oxidation sodium 10.5g is warming up to 100 ℃, be incubated 10 minutes, subsequently, hydrazine hydrate is reclaimed in underpressure distillation, is distilled to 110 ℃, vacuum 0.093Mpa, to there not being liquid to steam, there are a large amount of solid sodium chlorides to occur, need not to handle, cooling enters next step reaction;
When temperature is reduced to 70 ℃, add sodium methylate 9g, stir after 5 minutes, 65 ℃ add methylcarbonate 25ml, 68 ℃ of left and right sides back flow reaction 30 minutes reclaim methyl alcohol and methylcarbonate, add water-soluble clear (water as solvent) after the end, add hydrochloric acid (32%) 80ml, be heated to 65 ℃, add 5-nitryl furfural ester diacetate 26.5g, be heated to 84 ℃, be incubated 20 minutes, separate out yellow solid, be cooled to 40 ℃, suction filtration, washing, ethanol is washed, and gets product 25.2g after the oven dry, and recording fusing point is 240-242 ℃ (document is 241-243 ℃), the HPLC purity assay is 98.4%, and total recovery is 35.5%.
Embodiment 3:
Add earlier 80% hydrazine hydrate aqueous solution 35g, heat temperature raising to 90 ℃ drips Racemic glycidol 18.5g, and temperature is controlled at 95-100 ℃, after adding, 100 ℃ are incubated 1 hour, and hydrazine hydrate is reclaimed in underpressure distillation subsequently, is distilled to 110 ℃, to there not being liquid to steam, cooling directly enters next step reaction;
When temperature is reduced to 70 ℃, add sodium methylate 9g, stir after 5 minutes, 65 ℃ add methylcarbonate 25ml, 68 ℃ of left and right sides back flow reaction 30 minutes reclaim methyl alcohol and methylcarbonate, add water-soluble clear (water as solvent) after the end, add hydrochloric acid (32%) 80ml, be heated to 65 ℃, add 5-nitryl furfural ester diacetate 26.5g, be heated to 84 ℃, be incubated 20 minutes, separate out yellow solid, be cooled to 40 ℃, suction filtration, washing, ethanol is washed, and gets product 29.9g after the oven dry, and recording fusing point is 240-242 ℃ (document is 241-243 ℃), the HPLC purity assay is 98.7%, and total recovery is 42%.
Embodiment 4:
Add earlier 40% hydrazine hydrate aqueous solution 100g, heat temperature raising to 90 ℃ drips Racemic glycidol 18.5g, and temperature is controlled at 95-100 ℃, after adding, 100 ℃ are incubated 1 hour, and hydrazine hydrate is reclaimed in underpressure distillation subsequently, is distilled to 110 ℃, to there not being liquid to steam, cooling directly enters next step reaction;
When temperature is reduced to 70 ℃, add sodium methylate 9g, stir after 5 minutes, 65 ℃ add methylcarbonate 25ml, 68 ℃ of left and right sides back flow reaction 30 minutes reclaim methyl alcohol and methylcarbonate, add water-soluble clear (water as solvent) after the end, add hydrochloric acid (32%) 80ml, be heated to 65 ℃, add 5-nitryl furfural ester diacetate 26.5g, be heated to 84 ℃, be incubated 20 minutes, separate out yellow solid, be cooled to 40 ℃, suction filtration, washing, ethanol is washed, and gets product 29.5g after the oven dry, and recording fusing point is 240-242 ℃ (document is 241-243 ℃), the HPLC purity assay is 98.7%, and total recovery is 41.4%.
Embodiment 5:
Add earlier 80% hydrazine hydrate aqueous solution 75g, heat temperature raising to 80 ℃ drips 1-glycerin chlorohydrin 27.5 grams, after adding, progressively be warming up to 120-125 ℃, backflow is arranged, reacted 1 hour, be cooled to 40-45 ℃ afterwards, hydro-oxidation sodium 10.5g is warming up to 100 ℃, is incubated 10 minutes, subsequently, hydrazine hydrate is reclaimed in underpressure distillation, is distilled to 110 ℃, vacuum 0.093Mpa to there not being liquid to steam, has a large amount of solid sodium chlorides to occur, need not to handle, cooling enters next step reaction;
When temperature is reduced to 70 ℃, add sodium methylate 9g, stir after 5 minutes, 65 ℃ add methylcarbonate 25ml, 68 ℃ of left and right sides back flow reaction 30 minutes reclaim methyl alcohol and methylcarbonate, add water-soluble clear (water as solvent) after the end, add hydrochloric acid (32%) 80ml, be heated to 65 ℃, add 5-nitryl furfural ester diacetate 26.5g, be heated to 84 ℃, be incubated 20 minutes, separate out yellow solid, be cooled to 40 ℃, suction filtration, washing, ethanol is washed, and gets product 25.8g after the oven dry, and recording fusing point is 240-242 ℃ (document is 241-243 ℃), the HPLC purity assay is 98.5%, and total recovery is 36.4%.
Embodiment 6:
Add earlier 80% hydrazine hydrate aqueous solution 25g, heat temperature raising to 80 ℃ drips 1-glycerin chlorohydrin 27.5 grams, after adding, progressively be warming up to 120-125 ℃, backflow is arranged, reacted 1 hour, be cooled to 40-45 ℃ afterwards, hydro-oxidation sodium 10.5g is warming up to 100 ℃, is incubated 10 minutes, subsequently, hydrazine hydrate is reclaimed in underpressure distillation, is distilled to 110 ℃, vacuum 0.093Mpa to there not being liquid to steam, has a large amount of solid sodium chlorides to occur, need not to handle, cooling enters next step reaction;
When temperature is reduced to 70 ℃, add sodium methylate 9g, stir after 5 minutes, 65 ℃ add methylcarbonate 25ml, 68 ℃ of left and right sides back flow reaction 30 minutes reclaim methyl alcohol and methylcarbonate, add water-soluble clear (water as solvent) after the end, add hydrochloric acid (32%) 80ml, be heated to 65 ℃, add 5-nitryl furfural ester diacetate 26.5g, be heated to 84 ℃, be incubated 20 minutes, separate out yellow solid, be cooled to 40 ℃, suction filtration, washing, ethanol is washed, and gets product 24.2g after the oven dry, and recording fusing point is 240-242 ℃ (document is 241-243 ℃), the HPLC purity assay is 98.4%, and total recovery is 34.1%.
Embodiment 7:
Add earlier 80% hydrazine hydrate aqueous solution 50g, heat temperature raising to 80 ℃ drips 1-glycerin chlorohydrin 27.5 grams, after adding, progressively be warming up to 120-125 ℃, backflow is arranged, reacted 1 hour, be cooled to 40-45 ℃ afterwards, hydro-oxidation sodium 10.5g is warming up to 100 ℃, is incubated 10 minutes, subsequently, hydrazine hydrate is reclaimed in underpressure distillation, is distilled to 110 ℃, vacuum 0.093Mpa to there not being liquid to steam, has a large amount of solid sodium chlorides to occur, need not to handle, cooling enters next step reaction;
When temperature is reduced to 70 ℃, add sodium methylate 6g, stir after 5 minutes, 65 ℃ add methylcarbonate 25ml, 68 ℃ of left and right sides back flow reaction 30 minutes reclaim methyl alcohol and methylcarbonate, add water-soluble clear (water as solvent) after the end, add hydrochloric acid (32%) 80ml, be heated to 65 ℃, add 5-nitryl furfural ester diacetate 26.5g, be heated to 84 ℃, be incubated 20 minutes, separate out yellow solid, be cooled to 40 ℃, suction filtration, washing, ethanol is washed, and gets product 24.5g after the oven dry, and recording fusing point is 240-242 ℃ (document is 241-243 ℃), the HPLC purity assay is 98.6%, and total recovery is 34.5%.
Embodiment 8:
Add earlier 80% hydrazine hydrate aqueous solution 50g, heat temperature raising to 80 ℃ drips 1-glycerin chlorohydrin 27.5 grams, after adding, progressively be warming up to 120-125 ℃, backflow is arranged, reacted 1 hour, be cooled to 40-45 ℃ afterwards, hydro-oxidation sodium 10.5g is warming up to 100 ℃, is incubated 10 minutes, subsequently, hydrazine hydrate is reclaimed in underpressure distillation, is distilled to 110 ℃, vacuum 0.093Mpa to there not being liquid to steam, has a large amount of solid sodium chlorides to occur, need not to handle, cooling enters next step reaction;
When temperature is reduced to 70 ℃, add sodium methylate 15g, stir after 5 minutes, 65 ℃ add methylcarbonate 25ml, 68 ℃ of left and right sides back flow reaction 30 minutes reclaim methyl alcohol and methylcarbonate, add water-soluble clear (water as solvent) after the end, add hydrochloric acid (32%) 80ml, be heated to 65 ℃, add 5-nitryl furfural ester diacetate 26.5g, be heated to 84 ℃, be incubated 20 minutes, separate out yellow solid, be cooled to 40 ℃, suction filtration, washing, ethanol is washed, and gets product 23.8g after the oven dry, and recording fusing point is 240-242 ℃, the HPLC purity assay is 98.5%, and total recovery is 33.6%.
Claims (1)
1.5-the synthetic method of methylol-Nifurazolidone is that raw material reacts with 1-glycerin chlorohydrin, hydrazine hydrate, sodium hydroxide, sodium methylate, dimethyl ester and 5-nitro furfural diacetate, it is characterized in that:
(1) concentration is less than or equal to 80% the hydrazine hydrate aqueous solution or the hydrazine hydrate of recovery, is heated to 80-90 ℃, drips the 1-glycerin chlorohydrin, progressively be warming up to 100-130 ℃ then, the insulation of backflow one hour is arranged, and hydro-oxidation sodium when being cooled to 40-45 ℃ afterwards is in the 100 ℃ of insulations 10 minutes that heat up, hydrazine hydrate is reclaimed in underpressure distillation subsequently, when being distilled to 110 ℃, to there not being liquid to steam, a large amount of sodium-chlor precipitations appears, cooling, precipitation do not need processing directly to enter next step; Or add earlier concentration and be less than or equal to 80% hydrazine hydrate aqueous solution, heat temperature raising to 90 ℃ drips Racemic glycidol, controlled temperature 95-100 ℃, 100 ℃ are incubated 1 hour then, and hydrazine hydrate is reclaimed in underpressure distillation subsequently, is distilled to 110 ℃, to there not being liquid to steam, cooling enters next step;
Add sodium methylate when (2) treating that temperature is reduced to 70 ℃, stir, add methylcarbonate at 65 ℃, 68 ℃ of left and right sides back flow reaction 30 minutes reclaim methyl alcohol and methylcarbonate;
(3) add water-soluble clearly then, add hydrochloric acid, be heated to 65 ℃, add the 5-nitryl furfural ester diacetate, be heated to 84 ℃, be incubated 20 minutes, separate out yellow solid, be cooled to 40 ℃, suction filtration, washing, ethanol is washed, must product after the oven dry.
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Assignee: Quzhou Weirong Pharmaceutical & Chemical Co., Ltd. Assignor: Cao Guidong Contract fulfillment period: 2008.1.15 to 2013.1.14 contract change Contract record no.: 2009330000519 Denomination of invention: Synthesis method of 5-hydroxy methyl furazolidone Granted publication date: 20060913 License type: Exclusive license Record date: 2009.3.23 |
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Free format text: EXCLUSIVE LICENSE; TIME LIMIT OF IMPLEMENTING CONTACT: 2008.1.15 TO 2013.1.14; CHANGE OF CONTRACT Name of requester: QUZHOU WEIRONG PHARMACEUTICAL + CHEMICAL CO., LTD. Effective date: 20090323 |
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