CN104072369A - Diisopropyl malonate preparation process - Google Patents
Diisopropyl malonate preparation process Download PDFInfo
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- CN104072369A CN104072369A CN201410337145.0A CN201410337145A CN104072369A CN 104072369 A CN104072369 A CN 104072369A CN 201410337145 A CN201410337145 A CN 201410337145A CN 104072369 A CN104072369 A CN 104072369A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/08—Preparation of carboxylic acid esters by reacting carboxylic acids or symmetrical anhydrides with the hydroxy or O-metal group of organic compounds
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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Abstract
The invention belongs to the technical field of fine chemical engineering product preparation, and particularly relates to a diisopropyl malonate preparation process. The diisopropyl malonate preparation process comprises the following steps: using cyanoacetic acid as a raw material, and adding sulfuric acid for acid hydrolysis to generate an acid hydrolysis solution; adding isopropyl alcohol into the acid hydrolysis solution to perform esterification reaction, wherein the solution is divided into an upper layer solution and a lower layer solution after the reaction is completed; separating the upper layer solution, adding isopropyl alcohol into the upper layer solution to perform secondary esterification reaction by adopting a reactive distillation manner, steaming out isopropyl alcohol after the reaction is completed, neutralizing and purifying to obtain diisopropyl malonate; adding isopropyl alcohol into the lower layer solution for extraction, wherein the solution is layered secondary, an upper layer solution is used as a recycled and reused material used in the first esterification reaction in the next time, the isopropyl alcohol is steamed out from a lower layer solution, and the steamed isopropyl alcohol is used as a recycled and reused material used in the first esterification reaction in the next time. According to the process, a problem of decomposition of cyanoacetic acid at a later period in the dehydration process of the cyanoacetic acid is avoided, the use of other organic solvents is prevented, and the product yield is improved.
Description
Technical field
The invention belongs to fine chemical product preparing technical field, relate in particular to a kind of technique of preparing Diisopropyl malonate.
Background technology
Diisopropyl malonate, is called for short DIPM (Diisopropyl Malonate), and colourless liquid, is dissolved in the organic solvents such as ethanol, ether, acetone, benzene, water insoluble.Because the hydrogen atom on active methylene group in its molecule is easily replaced by other group, it at pesticide field, is the key intermediate of synthetic isoprothiolane.
In prior art, with reference to the preparation method of malonic ester, the preparation of Diisopropyl malonate mainly contains following several method:
One, alkali hydrolysis method: take Mono Chloro Acetic Acid as raw material, obtain cyanoacetic acid sodium after neutralization, cyaniding, add alkali, conventionally add sodium hydroxide or calcium hydroxide hydrolysis to generate malonate, and then acidifying, esterification, must be concentrated after the method completes, and malonate concentration process medium viscosity is very large, easily make whipping appts damage, someone proposes to adopt spray drying process, but can increase facility investment, the corresponding increase of steam consumption, the recovery of solid, powdery material is also more difficult, is difficult for realizing industrialization;
Two, Hydrochloric Acid Hydrolysis Method: take Mono Chloro Acetic Acid as raw material, after neutralization, cyaniding, acidifying are concentrated cyanoacetic acid, add reconcentration after hydrochloric acid hydrolysis, add again after dissolution with solvents propanedioic acid, ammonium chloride is separated, and then carry out esterification, the method is because the add-on of hydrochloric acid is larger, concentrated used chronic, during production, easily cause propanedioic acid to decompose, reactor used larger, product yield is lower, and very large by alcohol amount, cause the consumption of alcohol larger;
Three, sulphuric acid hydrolysis: take Mono Chloro Acetic Acid as raw material, after concentrating, neutralization, cyaniding, acidifying obtain cyanoacetic acid, after adding sulphuric acid hydrolysis, add again alcohol to carry out esterification, add toluene to make extraction agent simultaneously, the method is owing to having added extraction agent, thereby causes space-time yield lower, and inevitably causes the loss of extraction agent, in product, also have a small amount of extraction agent, the existence of benzene kind solvent also can cause environmental pollution and personal infringement simultaneously;
Four, dimethyl malonate ester-interchange method: for the product yielding poorly, the method equipment is simple, less investment, yet when output is larger, can consume a large amount of dimethyl malonates, therefore need corresponding supporting dimethyl malonate production line, and dimethyl malonate adopts traditional method, the Mono Chloro Acetic Acid of take is produced as raw material.
Malonic ester reaction belongs to esterification, is reversible reaction, and its reaction end is subject to the restriction of the equilibrium constant, and its reaction formula is as follows:
HOOCCH
2COOH+2ROH→ROOCCH
2COOR+2H
2O
Wherein, R is alkyl.
Diisopropyl malonate is low with respect to other malonic ester yields in preparation process, and as dimethyl malonate, diethyl malonate, propanedioic acid di-n-butyl, reason is that the equilibrium constant of Diisopropyl malonate is little.
Obviously, more few the carrying out that is more conducive to esterification of the moisture in reaction system, so traditional technology is all emphasized cyanoacetic acid when dehydration, moisture is more few better, yet in cyanoacetic acid dehydration, along with the increase of cyanoacetic acid concentration, temperature rises, and cyanoacetic acid decomposes serious, causes yield to reduce.Take in addition to add in addition the method for solvent, reaction product is dissolved in solvent, and it is moisture few in solvent, thereby promote esterification, carry out, yet this method has been added a large amount of solvents, causes space-time yield lower, and inevitably cause the loss of solvent, simultaneously in product, also have a small amount of solvent, and solvent is mostly benzene kind solvent, may contaminate environment, infringement human body.
Summary of the invention
The object of the invention is to for the deficiencies in the prior art, a kind of technique of preparing Diisopropyl malonate is provided, the problem of avoiding cyanoacetic acid dehydration later stage cyanoacetic acid to decompose, improves product yield, and does not need to use other organic solvents.
The present invention is achieved in that a kind of technique of preparing Diisopropyl malonate, comprises the following steps:
(1) acidolysis: take cyanoacetic acid solution as raw material, add sulphuric acid soln to carry out acidolysis, form acid hydrolysis solution;
(2) esterification for the first time: add Virahol in described acid hydrolysis solution, carry out esterification, reacted rear solution and be divided into two-layer up and down;
(3) esterification for the second time: the upper solution in separating step (2) also adds Virahol to adopt reactive distillation mode to carry out esterification for the second time, steams Virahol after react, and neutralization purification obtains Diisopropyl malonate;
(4) extraction recovery: will add Virahol to extract in the lower floor's solution after step (2) layering, solution secondary stratification, upper solution as next batch for the first time the material recycle of esterification apply mechanically, lower floor's solution steams Virahol, using the Virahol steaming as next batch for the first time the material recycle of esterification apply mechanically.
As a kind of improvement, the concentration of described cyanoacetic acid solution is 60～100wt%.
As improving further, the concentration of described cyanoacetic acid solution is 65～85wt%.
As a kind of improvement, the concentration of described sulphuric acid soln is 70～98wt%.
As a kind of improvement, the temperature of described esterification is for the first time 60～80 ℃.
As a kind of improvement, the concentration that adds aqueous isopropanol in described esterification is for the first time 70～100%.
As a kind of improvement, in described esterification for the first time, the mol ratio of Virahol and cyanoacetic acid is 2.05～4.0.
As a kind of improvement, in described esterification for the second time, the vacuum tightness of reactive distillation is-0.05～-0.08MPa.
As a kind of improvement, the system moisture when reaction of described esterification is for the second time reached home is less than 0.2wt%.
As a kind of improvement, the Virahol adding in described esterification is for the second time anhydrous isopropyl alcohol.
Owing to adopting technique scheme, the invention has the beneficial effects as follows:
The cyanoacetic acid that employing contains a certain amount of moisture is as raw material, avoids that the cyanoacetic acid as reaction raw materials is carried out to the dehydration operation later stage and occurs cyanoacetic acid resolution problem, and because system contains a certain amount of moisture, after acidolysis completes, system is liquid.
Because the ester that esterification generates is water insoluble, make reacted solution layering, upper solution is ester layer, separation also adds Virahol to adopt the mode of reactive distillation to continue esterification, the a small amount of sulfuric acid dissolving in upper solution and monoammonium sulfate can play the effect of catalyzer, because isopropyl alcohol and water forms azeotrope, the water generating so constantly steams with Virahol, moisture in system is constantly reduced, thereby promoting esterification carries out, avoid adding organic solvent, easy and simple to handle, improve yield, when added Virahol is anhydrous isopropyl alcohol, make moisture in system still less, the speed that adds fast response.
After esterification, in lower floor's solution of layering, contain water and monoammonium sulfate for the first time, add after Virahol, due to salt effect occurring, make solution layering, propanedioic acid and propanedioic acid list isopropyl ester are all dissolved in Virahol, form upper solution, can be used as next batch material and carry out esterification, easy and simple to handle, effect of extracting is good, lower floor's solution contains water, monoammonium sulfate, also contain a small amount of Virahol, Virahol is steamed as the material of next batch esterification, all the other compositions are done relevant treatment, avoid reaction mass waste, improve yield.
Embodiment
In order to make object of the present invention, technical scheme and advantage clearer, below in conjunction with embodiment, the present invention is further elaborated.Should be appreciated that specific embodiment described herein, only in order to explain the present invention, is not intended to limit the present invention.
Embodiment mono-
(1) acidolysis: the cyanoacetic acid that 1000kg concentration is 85wt% joins in 5000L glassed steel reaction vessels, drips the sulfuric acid that 1500kg concentration is 98wt%, and temperature is controlled at 65～80 ℃, after dropwising, is incubated 2 hours, forms acid hydrolysis solution;
(2) esterification for the first time: in the acid hydrolysis solution forming in step (1), add anhydrous isopropyl alcohol 1320kg, esterification 1～2 hour, temperature of reaction is 60～80 ℃, standing 1 hour, solution layering;
(3) esterification for the second time: another one reactor is removed on the upper strata of the solution in separating step (2), open vacuum, regulating vacuum tightness is-0.05～-0.08MPa, speed from reactor bottom with 60～70kg/h is led to anhydrous isopropyl alcohol in reactor, reacting by heating still steams the azeotrope of isopropyl alcohol and water simultaneously, after 10 hours, stop logical Virahol, make control of reaction end point be less than 0.2wt% at system moisture, continue to steam Virahol 0.5～1 hour, be cooled to 30～40 ℃, add sodium carbonate solution to neutralize, then entering rectifying tower purifies, obtain Diisopropyl malonate.
Embodiment bis-
(1) acidolysis: the cyanoacetic acid that 1000kg concentration is 60wt% joins in 5000L glassed steel reaction vessels, drips the sulfuric acid that 1500kg concentration is 70wt%, and temperature is controlled at 65～80 ℃, after dropwising, is incubated 2 hours, forms acid hydrolysis solution;
(2) material recycle is applied mechanically and esterification for the first time: will in the lower floor's solution after esterification layering for the first time in embodiment mono-step (2), add 600kg anhydrous isopropyl alcohol to extract, upper solution after extracting and demixing adds the acid hydrolysis solution in the present embodiment step (1) reactor, lower floor's solution steams Virahol, the Virahol steaming in step (3) in the Virahol steaming and embodiment mono-is added in the acid hydrolysis solution in the present embodiment step (1) reactor, adding in addition 1200kg concentration is the aqueous isopropanol of 90wt% again, esterification 1～2 hour, temperature of reaction is 60～80 ℃, standing 1 hour, solution layering,
(3) esterification for the second time: another one reactor is removed on the upper strata of the solution in separating step (2), open vacuum, regulating vacuum tightness is-0.05～-0.08MPa, speed from reactor bottom with 60～70kg/h is led to anhydrous isopropyl alcohol in reactor, reacting by heating still steams the azeotrope of isopropyl alcohol and water simultaneously, after 10 hours, stop logical Virahol, make control of reaction end point be less than 0.2wt% at system moisture, continue to steam Virahol 0.5～1 hour, be cooled to 30～40 ℃, add sodium carbonate solution to neutralize, then entering rectifying tower purifies, obtain Diisopropyl malonate.
Embodiment tri-
(1) acidolysis: the cyanoacetic acid that 900kg concentration is 65wt% joins in 5000L glassed steel reaction vessels, drips the sulfuric acid that 1500kg concentration is 75wt%, and temperature is controlled at 65～80 ℃, after dropwising, is incubated 2 hours, forms acid hydrolysis solution;
(2) material recycle is applied mechanically and esterification for the first time: will in the lower floor's solution after esterification layering for the first time in embodiment bis-steps (2), add 600kg anhydrous isopropyl alcohol to extract, upper solution after extracting and demixing adds the acid hydrolysis solution in the present embodiment step (1) reactor, lower floor's solution steams Virahol, the Virahol steaming in step (3) in the Virahol steaming and embodiment bis-is added in the acid hydrolysis solution in the present embodiment step (1) reactor, adding in addition 1000kg concentration is the aqueous isopropanol of 80wt% again, esterification 1～2 hour, temperature of reaction is 60～80 ℃, standing 1 hour, solution layering,
(3) esterification for the second time: another one reactor is removed on the upper strata of the solution in separating step (2), open vacuum, regulating vacuum tightness is-0.05～-0.08MPa, speed from reactor bottom with 60～70kg/h is led to anhydrous isopropyl alcohol in reactor, reacting by heating still steams the azeotrope of isopropyl alcohol and water simultaneously, after 10 hours, stop logical Virahol, make control of reaction end point be less than 0.2wt% at system moisture, continue to steam Virahol 0.5～1 hour, be cooled to 30～40 ℃, add sodium carbonate solution to neutralize, then entering rectifying tower purifies, obtain Diisopropyl malonate.
Embodiment tetra-
(1) acidolysis: the cyanoacetic acid that 1000kg concentration is 80% joins in 5000L glassed steel reaction vessels, drips the sulfuric acid that 1500kg concentration is 80wt%, and temperature is controlled at 65～80 ℃, after dropwising, is incubated 2 hours, forms acid hydrolysis solution;
(2) material recycle is applied mechanically and esterification for the first time: will in the lower floor's solution after esterification layering for the first time in embodiment tri-steps (2), add 600kg anhydrous isopropyl alcohol to extract, upper solution after extracting and demixing adds the acid hydrolysis solution in the present embodiment step (1) reactor, lower floor's solution steams Virahol, the Virahol steaming in step (3) in the Virahol steaming and embodiment tri-is added in the acid hydrolysis solution in the present embodiment step (1) reactor, adding in addition 800kg concentration is the aqueous isopropanol of 70wt% again, esterification 1～2 hour, temperature of reaction is 60～80 ℃, standing 1 hour, solution layering,
(3) esterification for the second time: another one reactor is removed on the upper strata of the solution in separating step (2), open vacuum, regulating vacuum tightness is-0.05～-0.08MPa, speed from reactor bottom with 60～70kg/h is led to anhydrous isopropyl alcohol in reactor, reacting by heating still steams the azeotrope of isopropyl alcohol and water simultaneously, after 10 hours, stop logical Virahol, make control of reaction end point be less than 0.2wt% at system moisture, continue to steam Virahol 0.5～1 hour, be cooled to 30～40 ℃, add sodium carbonate solution to neutralize, then entering rectifying tower purifies, obtain Diisopropyl malonate.
Embodiment five
(1) the anhydrous cyanoacetic acid of acidolysis: 600kg joins in 5000L glassed steel reaction vessels, drips the sulfuric acid that 1500kg concentration is 90%, and temperature is controlled at 65～80 ℃, after dropwising, is incubated 2 hours, forms acid hydrolysis solution;
(2) material recycle is applied mechanically and esterification for the first time: will in the lower floor's solution after esterification layering for the first time in embodiment tetra-steps (2), add 600kg anhydrous isopropyl alcohol to extract, upper solution after extracting and demixing adds the acid hydrolysis solution in the present embodiment step (1) reactor, lower floor's solution steams Virahol, the Virahol steaming in step (3) in the Virahol steaming and embodiment tetra-is added in the acid hydrolysis solution in the present embodiment step (1) reactor, add again in addition 600kg anhydrous isopropyl alcohol, esterification 1～2 hour, temperature of reaction is 60～80 ℃, standing 1 hour, solution layering,
(3) esterification for the second time: another one reactor is removed on the upper strata of the solution in separating step (2), open vacuum, regulating vacuum tightness is-0.05～-0.08MPa, speed from reactor bottom with 60～70kg/h is led to anhydrous isopropyl alcohol in reactor, reacting by heating still steams the azeotrope of isopropyl alcohol and water simultaneously, after 10 hours, stop logical Virahol, make control of reaction end point be less than 0.2wt% at system moisture, continue to steam Virahol 0.5～1 hour, be cooled to 30～40 ℃, add sodium carbonate solution to neutralize, then entering rectifying tower purifies, obtain Diisopropyl malonate.
After above-mentioned esterification completes, measure respectively embodiment mono-to embodiment five yield of esterification separately, measuring result is as following table:
| Batch | DIPM quality (kg) | Content | Yield |
| Embodiment mono- | 1692 | 99.5％ | 90％ |
| Embodiment bis- | 1786 | 99.8％ | 95％ |
| Embodiment tri- | 1776.6 | 99.6％ | 94.5％ |
| Embodiment tetra- | 1795.4 | 99.5％ | 95.5％ |
| Embodiment five | 1790 | 99.8％ | 95.2％ |
Due to the esterification of embodiment mono-, do not return cover material and use and to cause yield lower, in other embodiment, the yield of material esterification is all stabilized in more than 94%.
The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, all any modifications of doing within the spirit and principles in the present invention, be equal to and replace and improvement etc., within all should being included in protection scope of the present invention.
Claims (10)
1. a technique of preparing Diisopropyl malonate, is characterized in that, comprises the following steps:
(1) acidolysis: take cyanoacetic acid solution as raw material, add sulphuric acid soln to carry out acidolysis, form acid hydrolysis solution;
(2) esterification for the first time: add Virahol in described acid hydrolysis solution, carry out esterification, reacted rear solution and be divided into two-layer up and down;
(3) esterification for the second time: the upper solution in separating step (2) also adds Virahol to adopt reactive distillation mode to carry out esterification for the second time, steams Virahol after react, and neutralization purification obtains Diisopropyl malonate;
(4) extraction recovery: will add Virahol to extract in the lower floor's solution after step (2) layering, solution secondary stratification, upper solution as next batch for the first time the material recycle of esterification apply mechanically, lower floor's solution steams Virahol, using the Virahol steaming as next batch for the first time the material recycle of esterification apply mechanically.
2. the technique of preparation Diisopropyl malonate according to claim 1, is characterized in that, the concentration of described cyanoacetic acid solution is 60～100wt%.
3. the technique of preparation Diisopropyl malonate according to claim 2, is characterized in that, the concentration of described cyanoacetic acid solution is 65～85wt%.
4. the technique of preparation Diisopropyl malonate according to claim 1, is characterized in that, the concentration of described sulphuric acid soln is 70～98wt%.
5. the technique of preparation Diisopropyl malonate according to claim 1, is characterized in that, the temperature of described esterification is for the first time 60～80 ℃.
6. the technique of preparation Diisopropyl malonate according to claim 1, is characterized in that, the concentration that adds aqueous isopropanol in described esterification is for the first time 70～100wt%.
7. the technique of preparation Diisopropyl malonate according to claim 1, is characterized in that, in described esterification for the first time, the mol ratio of Virahol and cyanoacetic acid is 2.05～4.0.
8. the technique of preparation Diisopropyl malonate according to claim 1, is characterized in that, in described esterification for the second time, the vacuum tightness of reactive distillation is-0.05～-0.08MPa.
9. the technique of preparation Diisopropyl malonate according to claim 1, is characterized in that, the system moisture when reaction of described esterification is for the second time reached home is less than 0.2wt%.
10. the technique of preparation Diisopropyl malonate according to claim 1, is characterized in that, the Virahol adding in described esterification is for the second time anhydrous isopropyl alcohol.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107540543A (en) * | 2017-09-12 | 2018-01-05 | 潍坊滨海石油化工有限公司 | The preparation method of malonate |
| CN109020810A (en) * | 2018-09-06 | 2018-12-18 | 营创三征(营口)精细化工有限公司 | A kind of method of continuous synthesizing methyl diethyl malonate |
| CN113710641A (en) * | 2019-07-04 | 2021-11-26 | 株式会社Lg化学 | Preparation system and preparation method of diester-based composition |
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| US6395931B1 (en) * | 1997-08-13 | 2002-05-28 | Trikem S.A. | Malonic acid and esters thereof |
| CN103420833A (en) * | 2013-08-12 | 2013-12-04 | 重庆紫光化工股份有限公司 | Method for synthesizing p-toluenesulfonic acid-catalyzed dimethyl malonate |
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2014
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| JPS597136A (en) * | 1982-07-05 | 1984-01-14 | Daicel Chem Ind Ltd | Preparation of malonic acid ester |
| US6395931B1 (en) * | 1997-08-13 | 2002-05-28 | Trikem S.A. | Malonic acid and esters thereof |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107540543A (en) * | 2017-09-12 | 2018-01-05 | 潍坊滨海石油化工有限公司 | The preparation method of malonate |
| CN109020810A (en) * | 2018-09-06 | 2018-12-18 | 营创三征(营口)精细化工有限公司 | A kind of method of continuous synthesizing methyl diethyl malonate |
| CN113710641A (en) * | 2019-07-04 | 2021-11-26 | 株式会社Lg化学 | Preparation system and preparation method of diester-based composition |
| CN113710641B (en) * | 2019-07-04 | 2023-07-28 | 株式会社Lg化学 | System and method for preparing diester-based composition |
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