CN1785966A - Technology of synthesizing 2,3-dicyano ethyl propionate - Google Patents
Technology of synthesizing 2,3-dicyano ethyl propionate Download PDFInfo
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- CN1785966A CN1785966A CN 200510095252 CN200510095252A CN1785966A CN 1785966 A CN1785966 A CN 1785966A CN 200510095252 CN200510095252 CN 200510095252 CN 200510095252 A CN200510095252 A CN 200510095252A CN 1785966 A CN1785966 A CN 1785966A
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Abstract
The present invention relates to a process for synthesizing ethyl-2,3-dicyano-propionate which is used for produce pesticide intermediate. The basic method of said process includes the following steps: using the raw materials of ethyl cyanoacetate, paraformaldehyde and sodium cyanide to synthesize ethyl-2,3-dicyano-propionate in the medium dimethyl sulfoxide; after the ethyl-2,3-dicyano-propionate is synthesized, using solvent dichloromethane to extract the synthesized ethyl-2,3-dicyano-propionate from medium dimethyl sulfoxide, reduced pressure desolventizing to obtain crude product, then rectifying said crude product so as to obtain the refined product ethyl-2,3-cyano-propionate. Said invention also provides the concrete requirements of the above-mentioned every step. The purity of the obtained product is greater than 98%.
Description
Technical field:
The technology of a kind of Synthetic 2 of the present invention, 3-dicyano ethyl propanoate relates to and is used for producing pesticide intermediate, and 2, the 3-dicyano ethyl propanoate is one of the sharp strength spy of synthesizing new highly-effective low-residue sterilant (also claiming fipronil) main intermediate.
Background technology:
The technology of production 1,2-dicyano ethyl propanoate was to use ethanol as dielectric solvent in the past, and was just synthetic in ethanol medium raw material ethyl cyanoacetate, potassium cyanide and Paraformaldehyde 96, production 2,3-dicyano ethyl propanoate.
There is following shortcoming in the production technique of 2 before above-mentioned, 3-dicyano ethyl propanoate:
1, finished product 2,3-dicyano ethyl propanoate yield are lower, the highlyest can only reach 78%;
2, made 2,3-dicyano ethyl propanoate quality product is undesirable, 2,3-dicyano ethyl propanoate content can only accomplish 93～95%.
3, wherein the toxicity of raw material potassium cyanide is big, and the price height.
4, used alcohol solvent loss is bigger, and the alcoholic acid rate of recovery is less than 65%.
Will adopt new a kind of Synthetic 2, the processing method of 3-dicyano ethyl propanoate for this reason, adopt the new lower raw material of toxicity to replace potassium cyanide, adopt new dielectric solvent to replace ethanol,, and make the rate of recovery of novel solvent higher with acquisition higher yield and content.
Summary of the invention:
The technology that the purpose of this invention is to provide a kind of Synthetic 2,3-dicyano ethyl propanoate, in building-up process, reaction medium changed by ethanol use dimethyl sulfoxide (DMSO), and raw material potassium cyanide is used instead sodium cyanide replace, to reach the yield and the quality (content) of raising 2,3-dicyano ethyl propanoate, and the toxicity of raw material in the reduction production process, thereby improved production environment.
The technology of a kind of Synthetic 2,3-dicyano ethyl propanoate, it is characterized in that raw material ethyl cyanoacetate, Paraformaldehyde 96 and sodium cyanide Synthetic 2,3-dicyano ethyl propanoate in the medium dimethyl sulfoxide (DMSO), with methylene chloride synthetic good 2,3-dicyano ethyl propanoate are extracted from the medium dimethyl sulphoxide solution then, make crude product through the decompression desolventizing, again crude product rectifying is made elaboration 2,3-dicyano ethyl propanoate.
The technical process with this Synthetic 2,3-dicyano ethyl propanoate now is described below:
Earlier medium dimethyl sulfoxide (DMSO) and raw material ethyl cyanoacetate are pumped in the reactor, then, add raw material Paraformaldehyde 96 and sodium cyanide from the manhole of reactor, by temperature of charge is at 10 ℃～30 ℃ in the cooling maintenance still, reaction is about 20 hours under normal pressure; After reaction finishes, material all is transferred in another reactor, add hydrochloric acid and be neutralized to slightly acidic, extract with dichloroethane solution again, the extraction liquid after the extraction, promptly 2, the mixed solution of 3-dicyano ethyl propanoate and ethylene dichloride, all move in the 3rd reactor, be heated to below 70 ℃, precipitation reduces pressure, promptly adopting vacuum pump to make it reach negative pressure is-0.085MPa to obtain 2,3-dicyano ethyl propanoate crude product is again with 2,3-dicyano ethyl propanoate crude product carries out high vacuum rectification in the 4th reactor, its temperature is 150 ℃～160 ℃, pressure is 3 mmhg, makes elaboration 2 at last, the 3-dicyano ethyl propanoate, its product purity is greater than 98%.
After comparing, Synthetic 2 of the present invention, 3-dicyano ethyl propanoate technology and the technology of making reaction medium with ethanol in the past has following obvious advantage and effect:
1, synthetic finished product 2,3-dicyano ethyl propanoate yield can be up to 85%.
2, good product quality is in the product 2, purity 〉=98% of 3-dicyano ethyl propanoate.
3, product color is shallow, is transparent liquid.
4, the solvent dimethyl sulfoxide (DMSO) dielectric loss in the synthesis technique is little, the rate of recovery of dimethyl sulfoxide (DMSO)＞85%.
5, replace potassium cyanide with sodium cyanide in the raw material, both reduced production cost, alleviated toxicity again.
Description of drawings:
Fig. 1 is: 1500 liters of glassed steel reaction vessels R1 structural representations.
Fig. 2 is: 3000 liters of glassed steel reaction vessels R2 structural representations.
Fig. 3 is: 1500 liters of glassed steel reaction vessels R3 structural representations.
Fig. 4 is: 500 liters of stainless steel cauldron R6 structural representations.
Embodiment:
Embodiment 1: following is industrial production embodiment.
Referring to Fig. 1, Fig. 2, Fig. 3 and Fig. 4.
1, adopt the raw material and the reaction medium of following content:
Ethyl cyanoacetate material content:＞99%.
Paraformaldehyde 96 material content: 93～95%.
The sodium cyanide raw material of solid matter is industrial top grade product.
Reaction medium is a dimethyl sulfoxide (DMSO), its content: 〉=98%.
2,3 barrels of medium dimethyl sulfoxide (DMSO) liquid, 95 kilograms of about 600～650 kilograms and raw material ethyl cyanoacetate liquid, from the reactor R1 of Fig. 1 as seen, open vacuum valve (7) in 1500 liters of glassed steel reaction vessels R1, vacuum pipe and vacuum pump by vacuum direction C join, making reactor R1 is negative pressure, liquid material is pumped in the reactor R1 from suction port valve (4), opening stirrer (6) stirs, and open refrigerated brine valve (3), make refrigerated brine by the chuck (10) of import B, flow back in the salt solution reservoir by D by refrigerated brine outlet (9) through reactor R1.
3,50 kilograms of solid material sodium cyanides that add above-mentioned content from the manhole (8) of reactor R1,25 kilograms of Paraformaldehyde 96s are to reactor R1.Above-mentioned medium and raw material also can increase according to the above ratio and feed intake.
4, the manhole plate of off-response still R1 manhole (8), by temperature of charge in temperature tube (5) observation and the maintenance reactor R1 be: 10 ℃～30 ℃, the vacuum valve (7) of off-response still R1, above-mentioned raw materials synthesis under normal pressure in medium was got final product in about 20 hours, can look handleless cup (1) by glass and come material in the observing response still R1.
5, after reaction finishes, with material in the reactor R1 by still at the bottom of baiting valve (2) by vacuum, emit by material in the reactor R1 still and to flow to A and all move in 3000 liters of glassed steel reaction vessels R2.
6, add inlet valve (17) by hydrochloric acid and add about 200 kilograms of hydrochloric acid in reactor R2, make material be slightly acidic, pH value is about: 4～5.
7, A opening for feed place by liquid material suction port valve (15) adds 200 kilograms of dichloromethane extraction agent in reactor R2, open stirrer (21) and stir half an hour, stop then stirring, leave standstill half an hour, looking handleless cup (11) by glass observes, and open baiting valve (12) at the bottom of the still of reactor R2, extraction liquid outlet E in the reactor R2 releases with this extraction liquid, after collecting, then, add 200 kilograms of dichloromethane extraction agent again to reactor R2, repeat aforesaid operations four times, promptly add 800 kilograms of dichloromethane extraction agent altogether approximately, extract 4 times, will open refrigerated brine valve (13) during operation, refrigerated brine is flowed out through the refrigerated brine outlet D of chuck (14) from refrigerated brine outlet valve (20) from import B: temperature is by temperature tube (16) thermometric; Open vacuum valve (18) and vacuumize the absorption material from vacuum-lines C.The manhole of reactor R2 (19) but observing response.
8, above-mentioned extraction liquid from extraction liquid outlet E place in the reactor R2 is joined in the reactor R3 all, remaining residue liquid is packed into from the F exit, bottom of reactor R2 the container, so that reclaim the dimethyl sulfoxide (DMSO) medium that separates in the raffinate later on, use again after being provided with.
Referring to Fig. 3: (22) look handleless cup for glass among Fig. 3, (23) be baiting valve at the bottom of the still, G is the Way out of crude product 2,3-dicyano ethyl propanoate, H is the heat conductive oil inlet direction from the boiler house, (24) be the thermal oil inlet valve, (25) be temperature tube, (26) be stirrer, (27) are liquid material suction port valve, and E is for entering into the suction direction of reactor R3 from the extraction liquid of reactor R2, (28) be manhole, (29) be the thermal oil outlet valve, (30) are condenser, and (31) are valve, (34) be the still chuck, (33) are solvent tank.
Precipitation reduces pressure in 1500 liters of glassed steel reaction vessels R3, promptly slough the extraction agent methylene dichloride, temperature remains on less than 70 ℃ by temperature tube (25), vacuum tightness in the reactor R3 is about-0.085MPa, vacuumize by vacuum direction C place by opening valve (32), the dichloromethane solvent that steams is collected in the solvent tank (33), treats to reuse next time.
9, referring to Fig. 4: (35) are baiting valve at the bottom of the still among Fig. 4, when reactor R6 cleans, are used for emitting rinse water usefulness, close when producing at ordinary times.(36) be the thermal oil inlet valve, material is a metal valve.(37) be temperature tube, be used for measuring temperature in the reactor R6.(38) be anchor stirrer.(39) be liquid material suction port valve.(40) be the thermal oil outlet valve.(41) be condenser.(42) look handleless cup for glass.(43) be valve on the finished product storage tank.(44) be vacuum valve on the finished product storage tank.(45) be finished product storage tank.(46) be reactor R6 still chuck, put thermal oil in the chuck.C is the vacuum direction, and G is the direction that crude product 2,3-dicyano ethyl propanoate enter reactor R6, and H is the heat conductive oil inlet direction from the boiler house, and J is the thermal oil Way out that returns the boiler house.
After crude product 2,3-dicyano ethyl propanoate emitted below reactor R3, put into again in 500 liters of stainless steel cauldron R6 and carry out rectifying, vacuum tightness remains on 3 mmhg in the reactor R6, open the heating unit heating, make reactor R6 temperature remain on 150 ℃～160 ℃, under the normal circumstances, go out 2 at every turn, about 85 kilograms of 3-dicyano ethyl propanoate elaboration, purity 〉=98%.
10, can adopt gas chromatograph that above-mentioned two hydrocyanic ester elaboration are done following two kinds of detections, can choose wantonly wherein a kind of.
(1) the Constant Temperature Detection condition is as follows:
Column compartment temperature: 140 ℃;
Hydrogen flame detector: 280 ℃;
Vaporizing chamber: 280 ℃;
Column length: 15 meters;
Post footpath: 0.5 millimeter.
Weighting material is nonpolar or the low-pole weighting material.
(2) the temperature programming testing conditions is as follows:
Starting temperature: 75 ℃;
Temperature rise rate: 30 ℃/per minute;
Terminal temperature: 150 ℃;
Column length: 10 meters;
Post footpath: 0.32 millimeter.
Weighting material is nonpolar or the low-pole weighting material.
The annex explanation:
Reactor R4 and reactor R5 also are two enamel reaction stills, be used for the recovering medium dimethyl sulfoxide (DMSO) specially, this and 2, the production technique of 3-dicyano ethyl propanoate do not have and contacts directly, this technical process can be independent of 2, outside the 3-dicyano ethyl propanoate production process, can finish by the factory of the industrial raffinate of special recovery, so its production technique no longer is described in detail in detail.Dimethyl sulfoxide (DMSO) after the recovery can be used in once more in the reactor R1 and use as reaction medium after purity detecting, produces 2, the 3-dicyano ethyl propanoate.
Embodiment 2:
1, the raw material that is adopted is identical with embodiment 1 with reaction medium.
2,190 kilograms of 6 barrels of medium dimethyl sulfoxide (DMSO) (about 1200 kilograms～1300 kilograms) and raw material ethyl cyanoacetates are drawn in the still from reactor R1 liquid material suction port valve (4), open stirrer (6), and open refrigerated brine valve (3) salt solution is cooled through refrigerated brine outlet (9) by importer's chuck (10) in B enters still, refrigerated brine flows back in the salt solution reservoir by the D direction.
3, add 100 kilograms of solid material sodium cyanides from the manhole (8) of reactor R1,50 kilograms of Paraformaldehyde 96s are to still.
4, the manhole plate of the manhole of off-response still R1 (8), making the temperature of charge in the reactor R1 by above-mentioned refrigerated brine is 10 ℃～30 ℃, reaction is about 20 hours under normal pressure.
5, after aforesaid reaction vessel R1 internal reaction finishes, the material in the reactor R1 all is transferred in the reactor R2, method is identical with embodiment 1.
6, in reactor R2, add about 400 kilograms of hydrochloric acid, make material be slightly acidic (pH value is 4～5).
7, in reactor R2, add 400 kilograms of dichloromethane extraction agent, open stirrer (21) and stir half an hour, then, stop to stir and leave standstill half an hour again, again extraction liquid is released in reactor R2, collect, and repeat aforesaid operations four times.And last in the reactor R2 be the mixed solution of dimethyl sulfoxide (DMSO) and water, this mixed solution is put into drum, later on recovering medium dimethyl sulfoxide (DMSO) therefrom again.
8,4 extraction liquids of all that aforesaid reaction vessel R2 is released join in the reactor R3 all, the precipitation (promptly sloughing methylene dichloride) that reduces pressure distillation, keep temperature less than 70 ℃, vacuum tightness is about-0.085MPa, the dichloromethane solvent that distills out is collected in the storage tank, treats to reuse next time.At this moment lastly in the reactor R3 be 2,3-dicyano ethyl propanoate crude product.
9, last 2 in the reactor R3,3-dicyano ethyl propanoate crude product are emitted below reactor R3 after, put into again and carry out rectifying in the stainless steel cauldron R6, with 2,3-dicyano ethyl propanoate and small amount of impurities be separated, vacuum tightness remains on 3 mmhg in the reactor R6, temperature remains on 150 ℃, under the normal circumstances, can produce 2 at every turn, 3-dicyano ethyl propanoate elaboration is about 170 kilograms, purity 〉=98%.The testing conditions of product is identical with embodiment 1.
Claims (5)
1, the technology of a kind of Synthetic 2,3-dicyano ethyl propanoate, it is characterized in that raw material ethyl cyanoacetate, Paraformaldehyde 96 and sodium cyanide Synthetic 2,3-dicyano ethyl propanoate in the medium dimethyl sulfoxide (DMSO), with methylene chloride synthetic good 2,3-dicyano ethyl propanoate are extracted from the medium dimethyl sulphoxide solution then, make crude product through the decompression desolventizing, again crude product rectifying is made elaboration 2,3-dicyano ethyl propanoate.
2, the technology of Synthetic 2 according to claim 1,3-dicyano ethyl propanoate, it is characterized in that raw material ethyl cyanoacetate, Paraformaldehyde 96 and sodium cyanide are in the medium dimethyl sulfoxide (DMSO) when Synthetic 2,3-dicyano ethyl propanoate, temperature of charge remains on 10 ℃～30 ℃ with brine refrigeration in the reactor R1, and normal pressure reacted about 20 hours down; Medium dimethyl sulfoxide (DMSO) input amount is 600～650 kilograms, and raw material ethyl cyanoacetate liquid is 95 kilograms, and the solid material sodium cyanide is that 50 kilograms, Paraformaldehyde 96 are 25 kilograms, also can increase according to the above ratio to feed intake.
3, the technology of Synthetic 2 according to claim 1,3-dicyano ethyl propanoate, after it is characterized in that material behind the aforesaid reaction vessel R1 internal reaction is transferred in the reactor R2, be neutralized to slightly acidic with hydrochloric acid, pH value is about 4～5, in above-mentioned material charging capacity, the hydrochloric acid input amount is 200 kilograms, and the methylene chloride input amount is 200 kilograms, in reactor R2, stir half an hour, leave standstill half an hour; Use brine refrigeration in the reactor R2 chuck, obtain extraction liquid.
4, the technology of Synthetic 2 according to claim 1,3-dicyano ethyl propanoate, after the extraction liquid that it is characterized in that reactor R2 outlet joins reactor R3, be about in vacuum tightness-heat under the 0.085MPa, the still temperature keeps less than 70 ℃ of temperature, slough methylene chloride, make crude product 2,3 dicyano ethyl propanoates.
5, the technology of Synthetic 2 according to claim 1,3-dicyano ethyl propanoate, it is characterized in that above-mentioned crude product 2,3-dicyano ethyl propanoate are put into by reactor R3 carries out rectifying in the reactor R6, vacuum tightness remains on 3 mmhg in the reactor R6, with thermal oil at the chuck internal heating, reactor R6 temperature remains on 150 ℃～160 ℃, makes elaboration 2,3-dicyano ethyl propanoate.
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| CNB2005100952528A CN100391936C (en) | 2005-11-07 | 2005-11-07 | A kind of technique of synthesizing 2,3-ethyl dicyanopropionate |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2011086570A1 (en) * | 2010-01-18 | 2011-07-21 | Keki Hormusji Gharda | Process for preparation of cyanoalkylpropionate derivatives |
| WO2012147093A1 (en) | 2011-04-25 | 2012-11-01 | Keki Hormusji Gharda | A process for preparation of dicyanocarboxylate derivatives |
| CN103214395A (en) * | 2013-03-26 | 2013-07-24 | 南通市海圣药业有限公司 | Synthesizing process of 2,3-dicyanoethylpropionate |
| CN111675630A (en) * | 2020-07-21 | 2020-09-18 | 湖北金玉兰医药科技有限公司 | Production process of ethyl 2, 3-dicyanopropionate |
| CN112375012A (en) * | 2020-11-20 | 2021-02-19 | 杭州新桂实业有限公司 | Preparation method of ethyl 2, 3-dicyanopropionate |
| CN113372240A (en) * | 2021-07-02 | 2021-09-10 | 湖北金玉兰医药科技有限公司 | Green preparation process of ethyl 2, 3-dicyanopropionate |
| CN115677531A (en) * | 2022-11-04 | 2023-02-03 | 河北诚信集团有限公司 | Production process of ethyl 2, 3-dicyanopropionate |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB9120641D0 (en) * | 1991-09-27 | 1991-11-06 | Ici Plc | Heterocyclic compounds |
| DE4343528A1 (en) * | 1993-12-16 | 1995-06-22 | Schering Ag | New di-heterocyclyl-benzene or pyridine derivs. |
| GB9604691D0 (en) * | 1996-03-05 | 1996-05-01 | Rhone Poulenc Agriculture | New processes for preparing pesticidal intermediates |
| EP1264823A1 (en) * | 2001-06-08 | 2002-12-11 | Novartis AG | Process for the preparation of 2,3-dicyanopropionates |
-
2005
- 2005-11-07 CN CNB2005100952528A patent/CN100391936C/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2011086570A1 (en) * | 2010-01-18 | 2011-07-21 | Keki Hormusji Gharda | Process for preparation of cyanoalkylpropionate derivatives |
| WO2012147093A1 (en) | 2011-04-25 | 2012-11-01 | Keki Hormusji Gharda | A process for preparation of dicyanocarboxylate derivatives |
| US9309190B2 (en) | 2011-04-25 | 2016-04-12 | Keki Hormusji Gharda | Process for preparation of dicyanocarboxylate derivatives |
| CN103214395A (en) * | 2013-03-26 | 2013-07-24 | 南通市海圣药业有限公司 | Synthesizing process of 2,3-dicyanoethylpropionate |
| CN111675630A (en) * | 2020-07-21 | 2020-09-18 | 湖北金玉兰医药科技有限公司 | Production process of ethyl 2, 3-dicyanopropionate |
| CN112375012A (en) * | 2020-11-20 | 2021-02-19 | 杭州新桂实业有限公司 | Preparation method of ethyl 2, 3-dicyanopropionate |
| CN113372240A (en) * | 2021-07-02 | 2021-09-10 | 湖北金玉兰医药科技有限公司 | Green preparation process of ethyl 2, 3-dicyanopropionate |
| CN115677531A (en) * | 2022-11-04 | 2023-02-03 | 河北诚信集团有限公司 | Production process of ethyl 2, 3-dicyanopropionate |
| CN115677531B (en) * | 2022-11-04 | 2024-04-09 | 河北诚信集团有限公司 | Production process of ethyl 2, 3-dicyanopropionate |
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