CN102344359B - Method for preparing 3-butenoic acid - Google Patents
Method for preparing 3-butenoic acid Download PDFInfo
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- CN102344359B CN102344359B CN2011103389412A CN201110338941A CN102344359B CN 102344359 B CN102344359 B CN 102344359B CN 2011103389412 A CN2011103389412 A CN 2011103389412A CN 201110338941 A CN201110338941 A CN 201110338941A CN 102344359 B CN102344359 B CN 102344359B
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- butenoic acid
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- crotononitrile
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- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/584—Recycling of catalysts
Abstract
The invention discloses a method for preparing 3-butenoic acid. Firstly, 3-bromopropylene and cuprous cyanide are used for synthesizing 3-butylene nitrile under the catalysis condition of N-methyl-2-pyrrolidone; then temperature is controlled to be 75 DEG C, and 3-butylene nitrile is hydrolyzed into 3-butenoic acid under the catalysis condition of concentrated hydrochloric acid. Compared with the traditional preparation method of 3-butenoic acid, the preparation method disclosed by the invention has the outstanding advantages that 3-butylene nitrile is synthesized firstly, then 3-butylene nitrile is subjected to hydrolysis reaction to prepare 3-butenoic acid, reaction steps are less, operation is easy, product yield is high, purity is high, quality is good, reaction can be carried out at normal pressure, acid is taken as catalyst, product is easy to separate, and catalyst can be recycled, thus pollution to the environment can be avoided, good feasibility is achieved, ideal effect is achieved, industrialization production can be realized, good practicability is realized, and better economic benefit and social benefit can be produced.
Description
Technical field
The present invention relates to the preparation method of organic compound, be specifically related to a kind of method for preparing 3-butenoic acid.
Background technology
At present, the synthetic method commonly used of organic carboxyl acid mainly comprises: the 1) building-up reactions under the special catalyst condition comprises: 1. vinyl carbinol and CO react under the palladium chloride catalyst condition and generate carboxylic acid, 2. in THF, and take chlorallylene as raw material, I
2Be catalyzer, add Mg powder and logical CO, synthetic 3-butenoic acid, the i.e. method of grignard reaction; 2) by electrochemical method synthesis of carboxylic acid, namely with chlorallylene and CO
2Be raw material, tetraethylammonium bromide is for supporting salt, and Ti is working electrode, adopts the synthetic 3-butenoic acid of sacrificial anode protection single step reaction in a Room type electrolyzer; 3) prepare carboxylic acid by nitrile hydrolysis reactor, comprising: 1. the hydrolysis reaction of nitrile in neighbour's circle water prepares carboxylic acid, and 2. nitrile prepares carboxylic acid etc. in the Water Under solution of nitrilase.
All there is shortcoming separately in comprehensive above-mentioned all kinds of synthetic method, mainly contains: 1) condition of above-mentioned reaction have very harsh, the needs costliness that has or the catalyzer that easily pollutes, what have needs high temperature or high pressure etc.; 2) transformation efficiency of above-mentioned reaction or yield are not ideals very; 3) reaction that has is not easy control; The process of 4) reacting is too loaded down with trivial details etc.
Summary of the invention
Goal of the invention: for the deficiencies in the prior art, the purpose of this invention is to provide a kind of method for preparing 3-butenoic acid, the synthetic method simple with the realization response condition, that product yield is high, easy to operation.
Technical scheme: in order to realize the foregoing invention purpose, the technical solution used in the present invention is as follows:
A kind of method for preparing 3-butenoic acid uses first 3-bromopropylene and cuprous cyanide under the METHYLPYRROLIDONE catalytic condition, synthetic 3-crotononitrile; Then temperature control is 60 ~ 80 ℃, and under the concentrated hydrochloric acid catalytic condition, the hydrolysis of 3-crotononitrile generates 3-butenoic acid.
The above-mentioned method for preparing 3-butenoic acid, concrete steps comprise:
(1) the 3-crotononitrile is synthetic
Get 1.3 ~ 1.5mol CuCN and put into reaction vessel, then add METHYLPYRROLIDONE (its quality is 0.08 ~ 0.1 times of 3-bromopropylene), in reaction vessel, drip 3-bromopropylene 1.3 ~ 1.5mol, stirring reaction 1.5 ~ 2.5h, reaction product is distilled, collect the cut of temperature in the time of 116 ~ 122 ℃, obtain at last product; Wherein, the METHYLPYRROLIDONE quality is 0.08 ~ 0.1 times of 3-bromopropylene;
(2) 3-butenoic acid is synthetic
The 3-crotononitrile 1 ~ 1.1mol that gets above-mentioned preparation puts into reaction vessel, then adds the concentrated hydrochloric acid of 100 ~ 120mL, 60 ~ 80 ℃ of temperature controls, stirring reaction 10 ~ 20min, stopped heating adds the water of 100 ~ 120ml in the reaction vessel, demixing is told upper strata liquid, the subnatant extracted with diethyl ether, get extraction liquid and water layer, hybrid extraction liquid and upper strata liquid, pressure control 0.1MPa rectifying mixed solution is collected 70 ~ 75 ℃ cut, obtain the product 3-butenoic acid, remain and be organic solvent;
Product to step (1) is purified, and its purity is reached more than 99%.
The organic solvent of gained is used for extracting operation.
To the water layer of extracted with diethyl ether, carry out electrodialysis process, the gained concentrated hydrochloric acid is used for the hydrolysis reaction of 3-crotononitrile, and gained ammonia can be used for preparing CuCN.
Beneficial effect: compare with the preparation method of existing 3-butenoic acid, the outstanding advantages that the method for preparing 3-butenoic acid of the present invention has comprises: the present invention carries out first the synthetic of 3-crotononitrile, then the hydrolysis reaction that carries out the 3-crotononitrile prepares 3-butenoic acid, reactions steps is few, and is easy to operate, and efficiency of pcr product is high, purity is high, quality is good, reacts under normal pressure, and acid is catalyzer, product separates easily, and recoverable is avoided its contaminate environment, has good feasibility, reached comparatively desirable effect, can suitability for industrialized production, have good practicality, can produce preferably economic benefit and social benefit.
Embodiment
The present invention is described further below in conjunction with specific embodiment.
As shown in Figure 1, be the process flow sheet for preparing the method for 3-butenoic acid of the present invention.For each product in the synthetic route of the present invention is all used fully, the present invention carries out hydrolysis reaction to synthetic 3-crotononitrile and concentrated hydrochloric acid mixing, reaction product is extracted, and wherein organic layer distills, steaming organic solvent can reuse; Water layer carries out electrodialysis and reclaims nitrogenous source and hydrochloric acid, reuses.Following examples are all carried out with reference to this technical process.
Embodiment 1
Get the dry CuCN that crosses of 125g and put into the few bottle of four-hole, then add the 14gN-N-methyl-2-2-pyrrolidone N-, three flask mouths respectively and whipping appts, spherical condensation tube and thermometer connect.Take by weighing in addition the fresh about 168g of 3-bromopropylene and put into constant pressure funnel, another mouthful of dropping funnel and flask linked to each other.Then begin to drip the 3-bromopropylene and begin and stir.Control rate of addition, reaction can not heat or low temperature under carry out.After for some time in the flask temperature rise and liquid return arranged.Be added drop-wise to a certain amount of after, reaction beginning rapidly and reflux and accelerate, temperature rises rapidly.After dripping end for some time, backflow stops, and temperature reduces, and reaction approximately needs about 2h.Repack reflux into water distilling apparatus reaction product is distilled this moment, collects the cut of temperature in the time of 116 ~ 122 ℃, obtains at last the about 62-65g of product, and the content of 3-crotononitrile is 96%-97% by analysis, and its yield is about 90%.
For next step hydrolysis utilization, further purify to the product that obtains, its purity is reached more than 99%.Purification operations can be the purification operations of routine.
The 3-crotononitrile 67g that gets above-mentioned preparation puts into there-necked flask, then adds the concentrated hydrochloric acid of 100 ~ 120mL, and three flask mouths link to each other with whipping appts, spherical condensation tube, thermometer respectively.Flask is fixed in the oil bath heats, Temperature Setting is 60 ~ 80 ℃, and the several minutes afterreaction is obvious, namely begins to reflux, and a large amount of white crystal (being by analysis ammonia chloride crystal) occurs, and temperature Xu Su raises.Behind about 10 ~ 20min, stopped heating adds the water of 100 ~ 120ml in the flask, observes demixing.Isolate upper solution (acid) with separating funnel, subnatant gets extraction liquid and water layer with the extracted with diethyl ether twice of two parts of about 100ml, and extraction liquid and isolated upper strata acid solution are mixed.Mixed solution is put into flask and is linked to each other with serpentine condenser (adding in case of necessity one section separator column), carries out simple distillation operation.It is higher to meet the 3-butenoic acid boiling point, can take compression rectification.When pressure during in the 0.1MPa left and right sides, collect the cut of boiling point about 70 ~ 75 ℃, finally obtain the about 48 ~ 52g of product, remain and be organic solvent.Wherein organic solvent can be used for extracting operation.It is about 98% ~ 99% that this product contains 3-butenoic acid by analysis, and it is nearly 56 ~ 60% that its yield has reached, and the whole yield from the 3-bromopropylene to 3-butenoic acid has reached 51 ~ 55%.
In addition, can carry out conventional electrodialysis operation to water layer, get the hydrolysis reaction that the product concentrated hydrochloric acid can be used for the 3-crotononitrile, product ammonia can with CH
4Reaction makes HCN, for the preparation of CuCN.
Embodiment 2
Get the dry CuCN that crosses of 1.3mol and put into the few bottle of four-hole, then adding quality is 0.08 times METHYLPYRROLIDONE of 3-bromopropylene, three flask mouths respectively and whipping appts, spherical condensation tube and thermometer connect.Take by weighing in addition the fresh about 1.3mol of 3-bromopropylene and put into constant pressure funnel, another mouthful of dropping funnel and flask linked to each other.Then begin to drip the 3-bromopropylene and begin and stir.Control rate of addition, reaction can not heat or low temperature under carry out.After for some time in the flask temperature rise and liquid return arranged.Be added drop-wise to a certain amount of after, reaction beginning rapidly and reflux and accelerate, temperature rises rapidly.After dripping end for some time, backflow stops, and temperature reduces, and reaction approximately needs about 1.5h.Repack reflux into water distilling apparatus reaction product is distilled this moment, collects the cut of temperature in the time of 116 ~ 122 ℃, obtains at last the about 61-64g of product, and the content of 3-crotononitrile is about 96% by analysis, and its yield is about 90%.
For next step hydrolysis utilization, further purify to the product that obtains, its purity is reached more than 99%.Purification operations can be the purification operations of routine.
The 3-crotononitrile 1mol that gets above-mentioned preparation puts into 3 mouthfuls of flasks, then adds the concentrated hydrochloric acid of 120mL, and three flask mouths link to each other with whipping appts, spherical condensation tube, thermometer respectively.Flask is fixed in the oil bath heats, Temperature Setting is 75 ℃, and the several minutes afterreaction is obvious, namely begins to reflux, and a large amount of white crystal (being by analysis ammonia chloride crystal) occurs, and temperature Xu Su raises.Behind about 15min, stopped heating adds the water of 110ml in the flask, observes demixing.Isolate upper solution (acid) with separating funnel, subnatant gets extraction liquid and water layer with the extracted with diethyl ether twice of two parts of about 110ml, and extraction liquid and isolated upper strata acid solution are mixed.Mixed solution is put into flask and is linked to each other with serpentine condenser (adding in case of necessity one section separator column), carries out simple distillation operation.It is higher to meet the 3-butenoic acid boiling point, can take compression rectification.When pressure during in the 0.1MPa left and right sides, collect the cut of boiling point about 70 ~ 75 ℃, finally obtain the about 49 ~ 52g of product, remain and be organic solvent.Wherein organic solvent can be used for extracting operation.It is about 98% ~ 99% that this product contains 3-butenoic acid by analysis, and it is nearly 56 ~ 60% that its yield has reached, and the whole yield from the 3-bromopropylene to 3-butenoic acid has reached 51 ~ 55%.
In addition, can carry out conventional electrodialysis operation to water layer, get the hydrolysis reaction that the product concentrated hydrochloric acid can be used for the 3-crotononitrile, product ammonia can with CH
4Reaction makes HCN, for the preparation of CuCN.
Embodiment 3
Get the dry CuCN that crosses of 1.5mol and put into the few bottle of four-hole, then adding quality is 0.1 times METHYLPYRROLIDONE of 3-bromopropylene, three flask mouths respectively and whipping appts, spherical condensation tube and thermometer connect.Take by weighing in addition the fresh about 1.5mol of 3-bromopropylene and put into constant pressure funnel, another mouthful of dropping funnel and flask linked to each other.Then begin to drip the 3-bromopropylene and begin and stir.Control rate of addition, reaction can not heat or low temperature under carry out.After for some time in the flask temperature rise and liquid return arranged.Be added drop-wise to a certain amount of after, reaction beginning rapidly and reflux and accelerate, temperature rises rapidly.After dripping end for some time, backflow stops, and temperature reduces, and reaction approximately needs about 2.5h.Repack reflux into water distilling apparatus reaction product is distilled this moment, collects the cut of temperature in the time of 116 ~ 122 ℃, obtains at last the about 64-67g of product, and the content of 3-crotononitrile is 96% ~ 97% by analysis, and its yield is about 90%.
For next step hydrolysis utilization, further purify to the product that obtains, its purity is reached more than 99%.Purification operations can be the purification operations of routine.
The 3-crotononitrile 1.1mol that gets above-mentioned preparation puts into 3 mouthfuls of flasks, then adds the concentrated hydrochloric acid of 100 ~ 120mL, and three flask mouths link to each other with whipping appts, spherical condensation tube, thermometer respectively.Flask is fixed in the oil bath heats, Temperature Setting is 60-80 ℃, and the several minutes afterreaction is obvious, namely begins to reflux, and a large amount of white crystal (being by analysis ammonia chloride crystal) occurs, and temperature Xu Su raises.Behind about 20min, stopped heating adds the water of 100ml in the flask, observes demixing.Isolate upper solution (acid) with separating funnel, subnatant gets extraction liquid and water layer with the extracted with diethyl ether twice of two parts of about 100ml, and extraction liquid and isolated upper strata acid solution are mixed.Mixed solution is put into flask and is linked to each other with serpentine condenser (adding in case of necessity one section separator column), carries out simple distillation operation.It is higher to meet the 3-butenoic acid boiling point, can take compression rectification.When pressure during in the 0.1MPa left and right sides, collect the cut of boiling point about 70 ~ 75 ℃, finally obtain the about 48 ~ 52g of product, remain and be organic solvent.Wherein organic solvent can be used for extracting operation.It is about 98% ~ 99% that this product contains 3-butenoic acid by analysis, and it is nearly 56 ~ 60% that its yield has reached, and the whole yield from the 3-bromopropylene to 3-butenoic acid has reached 51 ~ 55%.
In addition, can carry out conventional electrodialysis operation to water layer, get the hydrolysis reaction that the product concentrated hydrochloric acid can be used for the 3-crotononitrile, product ammonia can with CH
4Reaction makes HCN, for the preparation of CuCN.
Embodiment 4
(1) the 3-crotononitrile is synthetic
Get the dry CuCN that crosses of 90g and put into the few bottle of four-hole, then add about 12g METHYLPYRROLIDONE, three flask mouths respectively and whipping appts, spherical condensation tube and thermometer connection.Take by weighing in addition fresh 3-bromopropylene 130g and put into constant pressure funnel, another mouthful of dropping funnel and flask linked to each other.Then begin to drip the 3-bromopropylene and begin and stir.The control rate of addition, after for some time in the flask temperature rise and liquid return arranged.Be added drop-wise to a certain amount of after, reaction beginning rapidly and reflux and accelerate, temperature rises rapidly.After dripping end for some time, backflow stops, and temperature reduces, and reaction approximately needs about two hours.Repack reflux into water distilling apparatus reaction product is distilled this moment, collects the cut of temperature in the time of 116 ~ 122 ℃, obtains at last the about 62g of product, and the content of 3-crotononitrile is about 97% by analysis, and its yield is about 90%.
For next step hydrolysis utilization, further purify to the product that obtains, its purity is reached more than 99%.Purification operations can be the purification operations of routine.
(2) 3-butenoic acid is synthetic
The 3-crotononitrile 67g that gets above-mentioned preparation puts into 3 mouthfuls of flasks, then adds the concentrated hydrochloric acid of 100ml, and three flask mouths link to each other with whipping appts, spherical condensation tube, thermometer respectively.Flask is fixed in the oil bath heats, Temperature Setting is 75 ℃, and the several minutes afterreaction is obvious, namely begins to reflux, and a large amount of white crystal (being by analysis ammonia chloride crystal) occurs, and temperature Xu Su raises.After about 20 minutes, stopped heating adds the water of 100ml in the flask, observes demixing.Isolate upper solution (acid) with separating funnel, subnatant gets extraction liquid and water layer with the extracted with diethyl ether twice of two parts of about 100ml, and extraction liquid and isolated upper strata acid solution are mixed.Mixed solution is put into flask and is linked to each other with serpentine condenser (adding in case of necessity one section separator column), carries out simple distillation operation.It is higher to meet the 3-butenoic acid boiling point, can take compression rectification.When pressure during at 0.1MPa, collect the cut of boiling point about 70 °, finally obtain the about 48g of product, remain and be organic solvent.Wherein organic solvent can be used for extracting operation.It is about 99.6% that this product contains 3-butenoic acid by analysis, and it is nearly 56% that its yield has reached, and the whole yield from the 3-bromopropylene to 3-butenoic acid has reached nearly 51%.
In addition, can carry out conventional electrodialysis operation to water layer, get the hydrolysis reaction that the product concentrated hydrochloric acid can be used for the 3-crotononitrile, product ammonia can with CH
4Reaction makes HCN, for the preparation of CuCN.
Method of the present invention is reacted under normal pressure, and acid is catalyzer, and product separates easily, and recoverable, avoids its contaminate environment, has good feasibility, and is easy and simple to handle, obtained comparatively desirable effect.
Claims (5)
1. a method for preparing 3-butenoic acid is characterized in that: use first 3-bromopropylene and cuprous cyanide under the METHYLPYRROLIDONE catalytic condition, synthetic 3-crotononitrile; Then temperature control is 60 ~ 80 ℃, and under the concentrated hydrochloric acid catalytic condition, the hydrolysis of 3-crotononitrile generates 3-butenoic acid.
2. the method for preparing 3-butenoic acid according to claim 1 is characterized in that concrete steps comprise:
(1) the 3-crotononitrile is synthetic
Get 1.3 ~ 1.5mol CuCN and put into reaction vessel, then add METHYLPYRROLIDONE, in reaction vessel, drip 3-bromopropylene 1.3 ~ 1.5mol, stirring reaction 1.5 ~ 2.5h, reaction product is distilled, collect the cut of temperature in the time of 116 ~ 122 ℃, obtain at last product; Wherein, the METHYLPYRROLIDONE quality is 0.08 ~ 0.1 times of 3-bromopropylene;
(2) 3-butenoic acid is synthetic
The 3-crotononitrile 1 ~ 1.1mol that gets above-mentioned preparation puts into reaction vessel, then adds the concentrated hydrochloric acid of 100 ~ 120mL, 60 ~ 80 ℃ of temperature controls, stirring reaction 10 ~ 20min, stopped heating adds the water of 100 ~ 120ml in the reaction vessel, demixing is told upper strata liquid, the subnatant extracted with diethyl ether, get extraction liquid and water layer, hybrid extraction liquid and upper strata liquid, pressure control 0.1MPa rectifying mixed solution is collected 70 ~ 75 ℃ cut, obtain the product 3-butenoic acid, remain and be organic solvent.
3. the method for preparing 3-butenoic acid according to claim 2 is characterized in that, the product of step (1) is purified, and its purity is reached more than 99%.
4. the method for preparing 3-butenoic acid according to claim 2 is characterized in that, in the step (2), the organic solvent of gained is used for extracting operation.
5. the method for preparing 3-butenoic acid according to claim 2 is characterized in that, in the step (2), to the water layer of extracted with diethyl ether, carries out electrodialysis process, and the gained concentrated hydrochloric acid is used for the hydrolysis reaction of 3-crotononitrile, and gained ammonia can be used for preparing CuCN.
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