CN103304484B - Method for synthesizing albendazole - Google Patents

Method for synthesizing albendazole Download PDF

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CN103304484B
CN103304484B CN201310195588.6A CN201310195588A CN103304484B CN 103304484 B CN103304484 B CN 103304484B CN 201310195588 A CN201310195588 A CN 201310195588A CN 103304484 B CN103304484 B CN 103304484B
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acetic acid
glacial acetic
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mass concentration
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CN103304484A (en
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王利明
夏秋景
陈洁
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Suzhou Chenghe Pharmaceutical & Chemical Co Ltd
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Abstract

The invention relates to a method for synthesizing albendazole. The method comprises the following steps of: (a) adding carbendazim, sodium sulfocyanate and glacial acetic acid to a reactor, dropwise adding 28% hydrogen peroxide while controlling the temperature to be 25-40 DEG C, carrying out heat preservation and reaction for 4-6 hours after the dropwise adding process is completed, and obtaining thiocyanide after glacial acetic acid is recovered through negative-pressure distillation; and (b) adding 20% aqueous potassium hydroxide solution to the thiocyanide while adding benzyltriethylammonium chloride, then dropwise adding 1-bromopropane, and reacting for 4-8 hours while controlling the temperature to be 45-60 DEG C, thereby obtaining the albendazole. According to the method, the potential safety hazard caused by the fact that a highly toxic substance, namely chlorine gas, is used for preparing albendazole is avoided successfully, and the influence on the quality and yield of the product, caused by side reactions resulting from the adoption of the chlorine gas, is eliminated successfully, so that the quality and yield of an intermediate are improved greatly; meanwhile, the adoption of alkali sulfide is cancelled, and then, the environmental pollution caused by a byproduct, namely thioether, produced due to excessive alkali sulfide is avoided, so that the method is perfectly suitable for industrial production; and furthermore, all the raw materials are low in cost and are purchased easily, and the operation is safe.

Description

A kind of synthetic method of Zental
Technical field
The present invention relates to the synthetic method of organic compound, specifically, is a kind of synthetic method of Zental.
Background technology
Zental and propanethiophenyl imidzole (Albendazole), molecular formula: C 12h 15n 3o 2s, molecular weight: 265.33, be U.S. smith kline list a company a kind of broad-spectrum high efficacy, low toxicity wormer, still extensively use both at home and abroad at present.It has multiple synthetic method, mainly contain o-Nitraniline method, diaminobenzidine, derosal method, wherein derosal method has two kinds, method one: by derosal through chlorosulphonation, iron powder reducing is propylated again, the shortcoming of this preparation technology is for using highly toxic product chlorsulfonic acid, and in building-up process, produce into a large amount of spent acid and iron mud, produce dangerous high, effective treatment process is there is no during three wastes output Datong District, method two: derosal and Sodium Thiocyanate 99 and chlorine reaction are obtained thiocyanide, then propylated obtains Zental after sodium sulfide reducing, reaction equation is:
The shortcoming of the method uses highly toxic product chlorine, serious potential safety hazard is brought to production, in building-up process, produce a large amount of side product chlorinated things simultaneously, thus have a strong impact on its yield and quality, on the other hand, the method uses Sodium Sulphide to make reductive agent, excessive Sodium Sulphide produces the thioether with serious stench in lower step propylated process with bromopropane reaction, and not easily process, bring serious restriction to industrial production, therefore the method cannot enter suitability for industrialized production at present.In sum, need one badly and avoid using highly toxic product, simultaneously intermediate quality and yield significantly improve, and do not produce the by product of contaminate environment, be applicable to completely suitability for industrialized production the method for synthesis Zental, but have not been reported about this method at present.
Summary of the invention
The object of the invention is, for deficiency of the prior art, to provide a kind of synthetic method of Zental.
For achieving the above object, the technical scheme that the present invention takes is:
A synthetic method for Zental, comprises the following steps:
A) in reaction unit, add derosal, Sodium Thiocyanate 99, Glacial acetic acid, drip 28% hydrogen peroxide at temperature control 25 ~ 40 DEG C, dropwise insulation reaction 4 ~ 6 hours, vacuum distillation obtains thiocyanide after reclaiming Glacial acetic acid;
B) add in thiocyanide by 20% potassium hydroxide aqueous solution, after adding benzyltriethylammoinium chloride, drip 1-N-PROPYLE BROMIDE, temperature control 45 ~ 60 DEG C, reacts 4 ~ 8 hours, obtains Zental simultaneously,
Reaction equation is:
Wherein, the mol ratio of described derosal, Sodium Thiocyanate 99, hydrogen peroxide, potassium hydroxide aqueous solution, 1-N-PROPYLE BROMIDE is 1: 1.1 ~ 1.5: 3 ~ 5: 3.5 ~ 4.5: 1.1 ~ 1.3, the consumption of described Glacial acetic acid is 5 ~ 8 times of derosal weight, and the consumption of described benzyltriethylammoinium chloride is 1% ~ 3% of derosal weight.
Preferably, the temperature described in step 1) is 30 ~ 35 DEG C, and the reaction times is 4 hours; Step 2) described in temperature be 55 ~ 60 DEG C, the reaction times is 6 hours.
As a preferred embodiment of the present invention, the mol ratio of described derosal, Sodium Thiocyanate 99, hydrogen peroxide, potassium hydroxide aqueous solution, 1-N-PROPYLE BROMIDE is 1: 1.15: 4: 3.5: 1.1, the consumption of described Glacial acetic acid is 5 times of derosal weight, and the consumption of described benzyltriethylammoinium chloride is 1.5% of derosal weight.
As a preferred embodiment of the present invention, the mol ratio of described derosal, Sodium Thiocyanate 99, hydrogen peroxide, potassium hydroxide aqueous solution, 1-N-PROPYLE BROMIDE is 1: 1.3: 3.5: 4: 1.3, the consumption of described Glacial acetic acid is 5 times of derosal weight, and the consumption of described benzyltriethylammoinium chloride is 2.3% of derosal weight.
As a preferred embodiment of the present invention, the mol ratio of described derosal, Sodium Thiocyanate 99, hydrogen peroxide, potassium hydroxide aqueous solution, 1-N-PROPYLE BROMIDE is 1: 1.5: 5: 4.5: 1.2, the consumption of described Glacial acetic acid is 5 times of derosal weight, and the consumption of described benzyltriethylammoinium chloride is 2.7% of derosal weight.
As a preferred embodiment of the present invention, the mol ratio of described derosal, Sodium Thiocyanate 99, hydrogen peroxide, potassium hydroxide aqueous solution, 1-N-PROPYLE BROMIDE is 1: 1.1: 3: 4: 1.3, the consumption of described Glacial acetic acid is 8 times of derosal weight, and the consumption of described benzyltriethylammoinium chloride is 3.0% of derosal weight.
As a preferred embodiment of the present invention, the mol ratio of described derosal, Sodium Thiocyanate 99, hydrogen peroxide, potassium hydroxide aqueous solution, 1-N-PROPYLE BROMIDE is 1: 1.5: 3: 4.5: 1.1, the consumption of described Glacial acetic acid is 6 times of derosal weight, and the consumption of described benzyltriethylammoinium chloride is 1.0% of derosal weight.
It should be noted that, described derosal english common name: carbendazim, chemical name: N-(2-benzimidazolyl base)-Urethylane, molecular formula: C 9h 9n 3o 2, structural formula:
, be a kind of be high-efficiency low-toxicity systemic fungicide; Described Sodium Thiocyanate 99 English name: Sodium sulfocyanate, molecular formula: NaSCN; Described hydrogen peroxide chemical formula is H 2o 2; Described 1-N-PROPYLE BROMIDE English name: propyl bromide, molecular formula: C 3h 7br or PrBr; Described Glacial acetic acid and acetic acid; Described benzyltriethylammoinium chloride English name: Benzyltriethylammonium chloride, linear formula: C 6h 5cH 2n (Cl) (C 2h 5) 3, molecular structural formula: .
The invention has the advantages that:
The present invention adopts derosal and Sodium Thiocyanate 99 and hydrogen peroxide, be that solvent reaction obtains thiocyanide with Glacial acetic acid, thiocyanide directly and potassium hydroxide, 1-N-PROPYLE BROMIDE is under the effect of phase-transfer catalyst benzyltriethylammoinium chloride, be obtained by reacting Zental, successfully solve the problem using highly toxic product chlorine to cause, eliminate potential safety hazard and use the side reaction that brings of chlorine having a strong impact on quality product and yield, intermediate quality and yield are significantly improved, cancel simultaneously and use Sodium Sulphide, avoid causing serious environmental issue because of its excessive rear generation by product thioether, and adopt phase-transfer catalyst can not produce the by product of contaminate environment, be applicable to suitability for industrialized production completely.In addition, the raw material such as derosal, Sodium Thiocyanate 99, hydrogen peroxide, potassium hydroxide is all cheap and easily purchase, operational safety.
Embodiment
Below embodiment provided by the invention is elaborated.
embodiment 1
Derosal 100 grams (0.52mol) is added in 1500ml reaction flask, Sodium Thiocyanate 99 49 grams (0.60mol), 500 grams, Glacial acetic acid, control temperature 30 ~ 35 DEG C under agitation condition, slow 253 grams, dropping mass concentration 28% hydrogen peroxide (2.08mol), dropwise maintenance 30 ~ 35 DEG C insulation 4 hours, insulation terminates, vacuum distillation reclaims Glacial acetic acid, Glacial acetic acid distillation is complete, adding 500 gram mass concentration is 20% potassium hydroxide aqueous solution (1.82mol) and 1.5 grams of benzyltriethylammoinium chlorides, temperature 45 ~ 50 DEG C is regulated to drip 70.356g(0.572mol under agitation condition) 1-N-PROPYLE BROMIDE, dropwise, slowly be warming up to 55 ~ 60 DEG C, and be incubated 6 hours at this temperature, insulation end is cooled to room temperature and filters, tap water washing is to neutral, drain, by material mass concentration 5% dissolving with hydrochloric acid, activated carbon decolorizing filters, mass concentration 15% sodium hydroxide solution is neutralized to pH=7-8, suction filtration, the washing of material tap water is to pH=7-8, vacuum-drying under material 60 DEG C of conditions, obtain product 113.6 grams, for white crystalline powder, odorless, tasteless, fusing point 206 ~ 212 DEG C, content: 99.52%(HPLC), yield 82.33%.
embodiment 2
Derosal 109.6 grams (0.57mol) is added in 1500ml reaction flask, Sodium Thiocyanate 99 60.5 grams (0.74mol), 548 grams, Glacial acetic acid, control temperature 30 ~ 35 DEG C under agitation condition, slow 242 grams, dropping mass concentration 28% hydrogen peroxide (2.00mol), dropwise maintenance 30 ~ 35 DEG C insulation 4 hours, insulation terminates, vacuum distillation reclaims Glacial acetic acid, Glacial acetic acid distillation is complete, add 638 gram mass concentration 20% potassium hydroxide aqueous solutions (2.28mol) and 2.5 grams of benzyltriethylammoinium chlorides, temperature 45 ~ 50 DEG C is regulated to drip 91.143g(0.741mol under agitation condition) 1-N-PROPYLE BROMIDE, dropwise, slowly be warming up to 55 ~ 60 DEG C, and be incubated 6 hours at this temperature, insulation end is cooled to room temperature and filters, tap water washing is to neutral, drain, by material mass concentration 5% dissolving with hydrochloric acid, activated carbon decolorizing filters, mass concentration 15% sodium hydroxide solution is neutralized to pH=7-8, suction filtration, the washing of material tap water is to pH=7-8, vacuum-drying under material 60 DEG C of conditions, obtain product 123.6 grams, for white crystalline powder, odorless, tasteless, fusing point 206 ~ 212 DEG C, content: 99.47%(HPLC), yield 81.71%.
embodiment 3
Derosal 90 grams (0.47mol) is added in 1500ml reaction flask, Sodium Thiocyanate 99 56.7 grams (0.70mol), 450 grams, Glacial acetic acid, control temperature 30 ~ 35 DEG C under agitation condition, slow 285 grams, dropping mass concentration 28% hydrogen peroxide (2.35mol), dropwise maintenance 30 ~ 35 DEG C insulation 4 hours, insulation terminates, vacuum distillation reclaims Glacial acetic acid, Glacial acetic acid distillation is complete, add 593 gram mass concentration 20% potassium hydroxide aqueous solutions (2.12mol) and 2.5 grams of benzyltriethylammoinium chlorides, temperature 45 ~ 50 DEG C is regulated to drip 69.372g(0.564mol under agitation condition) 1-N-PROPYLE BROMIDE, dropwise, slowly be warming up to 55 ~ 60 DEG C, and be incubated 6 hours at this temperature, insulation end is cooled to room temperature and filters, tap water washing is to neutral, drain, material is used 5% dissolving with hydrochloric acid, activated carbon decolorizing filters, mass concentration 15% sodium hydroxide solution is neutralized to pH=7-8, suction filtration, the washing of material tap water is to pH=7-8, vacuum-drying under material 60 DEG C of conditions, obtain product 105.8 grams, for white crystalline powder, odorless, tasteless, fusing point 206 ~ 212 DEG C, content: 99.63%(HPLC), yield 84.88%.
embodiment 4
Derosal 95.6 grams (0.50mol) is added in 1500ml reaction flask, Sodium Thiocyanate 99 0.55mol, 764.8 grams, Glacial acetic acid, control temperature 25 ~ 30 DEG C under agitation condition, slow dropping mass concentration 28% hydrogen peroxide 1.50mol, dropwise maintenance 25 ~ 30 DEG C insulation 6 hours, insulation terminates, vacuum distillation reclaims Glacial acetic acid, Glacial acetic acid distillation is complete, add mass concentration 20% potassium hydroxide aqueous solution (2.00mol) and 2.868 grams of benzyltriethylammoinium chlorides, temperature 45 ~ 50 DEG C is regulated to drip 0.65mol 1-N-PROPYLE BROMIDE under agitation condition, dropwise, slowly be warming up to 50 ~ 55 DEG C, and be incubated 8 hours at this temperature, insulation end is cooled to room temperature and filters, tap water washing is to neutral, drain, material is used 5% dissolving with hydrochloric acid, activated carbon decolorizing filters, mass concentration 15% sodium hydroxide solution is neutralized to pH=7-8, suction filtration, the washing of material tap water is to pH=7-8, vacuum-drying under material 60 DEG C of conditions, obtain product 108.6 grams, for white crystalline powder, odorless, tasteless, fusing point 206 ~ 212 DEG C, content: 99.41%(HPLC), yield 81.06%.
embodiment 5
Derosal 105.2 grams (0.55mol) is added in 1500ml reaction flask, Sodium Thiocyanate 99 0.825mol, 631.2 grams, Glacial acetic acid, control temperature 35 ~ 40 DEG C under agitation condition, slow dropping mass concentration 28% hydrogen peroxide 1.65mol, dropwise maintenance 35 ~ 40 DEG C insulation 5 hours, insulation terminates, vacuum distillation reclaims Glacial acetic acid, Glacial acetic acid distillation is complete, add mass concentration 20% potassium hydroxide aqueous solution (2.475mol) and 1.052 grams of benzyltriethylammoinium chlorides, temperature 45 ~ 50 DEG C is regulated to drip 0.605mol 1-N-PROPYLE BROMIDE under agitation condition, dropwise, slow cooling to 35 ~ 40 DEG C, and be incubated 5 hours at this temperature, insulation end is cooled to room temperature and filters, tap water washing is to neutral, drain, material is used 5% dissolving with hydrochloric acid, activated carbon decolorizing filters, mass concentration 15% sodium hydroxide solution is neutralized to pH=7-8, suction filtration, the washing of material tap water is to pH=7-8, vacuum-drying under material 60 DEG C of conditions, obtain product 110.4 grams, for white crystalline powder, odorless, tasteless, fusing point 206 ~ 212 DEG C, content: 99.42%(HPLC), yield 81.12%.
embodiment 6
Derosal 100 grams (0.52mol) is added in 1500ml reaction flask, Sodium Thiocyanate 99 0.52mol, 500 grams, Glacial acetic acid, control temperature 35 ~ 40 DEG C under agitation condition, slow dropping mass concentration 28% hydrogen peroxide 2.60mol, dropwise maintenance 35 ~ 40 DEG C insulation 5 hours, insulation terminates, vacuum distillation reclaims Glacial acetic acid, Glacial acetic acid distillation is complete, add mass concentration 20% potassium hydroxide aqueous solution (2.08mol) and 1.5 grams of benzyltriethylammoinium chlorides, temperature 45 ~ 50 DEG C is regulated to drip 0.676mol 1-N-PROPYLE BROMIDE under agitation condition, dropwise, slow cooling to 35 ~ 40 DEG C, and be incubated 5 hours at this temperature, insulation end is cooled to room temperature and filters, tap water washing is to neutral, drain, material is used 5% dissolving with hydrochloric acid, activated carbon decolorizing filters, mass concentration 15% sodium hydroxide solution is neutralized to pH=7-8, suction filtration, the washing of material tap water is to pH=7-8, vacuum-drying under material 60 DEG C of conditions, obtain product 106.3 grams, for white crystalline powder, odorless, tasteless, fusing point 206 ~ 212 DEG C, content: 99.31%(HPLC), yield 80.04%.
embodiment 7
Derosal 100 grams (0.52mol) is added in 1500ml reaction flask, Sodium Thiocyanate 99 0.78mol, 500 grams, Glacial acetic acid, control temperature 35 ~ 40 DEG C under agitation condition, slow dropping mass concentration 28% hydrogen peroxide 1.56mol, dropwise maintenance 35 ~ 40 DEG C insulation 5 hours, insulation terminates, vacuum distillation reclaims Glacial acetic acid, Glacial acetic acid distillation is complete, add mass concentration 20% potassium hydroxide aqueous solution (1.82mol) and 1.5 grams of benzyltriethylammoinium chlorides, temperature 45 ~ 50 DEG C is regulated to drip 0.52mol 1-N-PROPYLE BROMIDE under agitation condition, dropwise, slow cooling to 35 ~ 40 DEG C, and be incubated 5 hours at this temperature, insulation end is cooled to room temperature and filters, tap water washing is to neutral, drain, material is used 5% dissolving with hydrochloric acid, activated carbon decolorizing filters, mass concentration 15% sodium hydroxide solution is neutralized to pH=7-8, suction filtration, the washing of material tap water is to pH=7-8, vacuum-drying under material 60 DEG C of conditions, obtain product 103.51 grams, for white crystalline powder, odorless, tasteless, fusing point 206 ~ 212 DEG C, content: 99.35%(HPLC), yield 81.34%.
The above is only the preferred embodiment of the present invention; it should be pointed out that for those skilled in the art, under the prerequisite not departing from the inventive method; can also make some improvement and supplement, these improve and supplement and also should be considered as protection scope of the present invention.

Claims (2)

1. the synthetic method of a Zental, it is characterized in that, comprise the following steps: in 1500ml reaction flask, add derosal 0.52mol, Sodium Thiocyanate 99 0.52mol, 500 grams, Glacial acetic acid, control temperature 35 ~ 40 DEG C under agitation condition, slow dropping mass concentration 28% hydrogen peroxide 2.60mol, dropwise maintenance 35 ~ 40 DEG C insulation 5 hours, insulation terminates, vacuum distillation reclaims Glacial acetic acid, Glacial acetic acid distillation is complete, add mass concentration 20% potassium hydroxide aqueous solution and 1.5 grams of benzyltriethylammoinium chlorides of 2.08mol, temperature 45 ~ 50 DEG C is regulated to drip 0.676mol 1-N-PROPYLE BROMIDE under agitation condition, dropwise, slow cooling to 35 ~ 40 DEG C, and be incubated 5 hours at this temperature, insulation end is cooled to room temperature and filters, tap water washing is to neutral, drain, material is used 5% dissolving with hydrochloric acid, activated carbon decolorizing filters, mass concentration 15% sodium hydroxide solution is neutralized to pH=7-8, suction filtration, the washing of material tap water is to pH=7-8, vacuum-drying under material 60 DEG C of conditions, obtain Zental.
2. the synthetic method of a Zental, it is characterized in that, comprise the following steps: in 1500ml reaction flask, add derosal 0.52mol, Sodium Thiocyanate 99 0.78mol, 500 grams, Glacial acetic acid, control temperature 35 ~ 40 DEG C under agitation condition, slow dropping mass concentration 28% hydrogen peroxide 1.56mol, dropwise maintenance 35 ~ 40 DEG C insulation 5 hours, insulation terminates, vacuum distillation reclaims Glacial acetic acid, Glacial acetic acid distillation is complete, add mass concentration 20% potassium hydroxide aqueous solution and 1.5 grams of benzyltriethylammoinium chlorides of 1.82mol, temperature 45 ~ 50 DEG C is regulated to drip 0.52mol 1-N-PROPYLE BROMIDE under agitation condition, dropwise, slow cooling to 35 ~ 40 DEG C, and be incubated 5 hours at this temperature, insulation end is cooled to room temperature and filters, tap water washing is to neutral, drain, material is used 5% dissolving with hydrochloric acid, activated carbon decolorizing filters, mass concentration 15% sodium hydroxide solution is neutralized to pH=7-8, suction filtration, the washing of material tap water is to pH=7-8, vacuum-drying under material 60 DEG C of conditions, obtain Zental.
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CN106167468B (en) * 2016-07-25 2018-12-25 安徽千和新材料科技发展有限公司 A method of replace N-Propyl Bromide to prepare albendazole with chloropropane
CN113912549B (en) * 2020-07-08 2022-11-15 山东国邦药业有限公司 Preparation method of albendazole

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