CN105461560A - Synthesizing method for ethyl difluoroacetate - Google Patents

Synthesizing method for ethyl difluoroacetate Download PDF

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Publication number
CN105461560A
CN105461560A CN201511033926.1A CN201511033926A CN105461560A CN 105461560 A CN105461560 A CN 105461560A CN 201511033926 A CN201511033926 A CN 201511033926A CN 105461560 A CN105461560 A CN 105461560A
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reaction
temperature
condenser
raw material
pass
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相继欣
郭海强
闫锐
肖山
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Tianjin Changlu Chemical New Materials Co Ltd
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Tianjin Changlu Chemical New Materials Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • C07C51/58—Preparation of carboxylic acid halides
    • 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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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

The invention relates to a synthesizing method, in particular to a synthesizing method for ethyl difluoroacetate, and aims at solving the problems that an existing synthesizing method for the ethyl difluoroacetate is complex in technological process, low in safety and high in preparation cost. The synthesizing method comprises the steps that 1, a catalyst is prepared, wherein a tubular reactor is filled with Al2O3 powder with the certain particle size meshes, it is guaranteed that the height of the Al2O3 powder is in a heating area of the tubular furnace, the temperature is increased to 250 DEG C-300 DEG C under nitrogen protection and kept for 12 h, CHaFbClc gas is continuously and slowly introduced for a reaction, the reaction temperature is set at 250 DEG C-300 DEG C, and the reaction time is set for 12 h; 2, 1,1,2,2-tetrafluoroethyl ethylether is taken as raw materials for a reaction under the conditions of the certain temperature and the catalyst, and an intermediate does not need to be separated and is directly collected through condenser to be converted into ethyl ester. The method belongs to the field of chemical engineering.

Description

A kind of synthetic method of ethyl difluoro
Technical field
The present invention relates to a kind of synthetic method, be specifically related to a kind of synthetic method of ethyl difluoro, belong to chemical field.
Background technology
The molecular formula of ethyl difluoro is: CHF 2cOOC 2h 5, be transparent or weak yellow liquid, have fragrance and minimal irritation, be slightly soluble in water, with immiscible organic solvent, meeting water and easily decompose, is a kind of novel medicine and pesticide intermediate, and market outlook are had an optimistic view of.
According to bibliographical information, the main technique preparing ethyl difluoro at present has: (1), with tetrafluoroethylene Material synthesis difluoroacetic acid, the main drawback of this technique is that tetrafluoroethylene belongs to inflammable and explosive on the one hand, and not easily transports, and needs onsite application; Cost is relatively high on the other hand.(2) take dichloroacetyl chloride as the technique that raw material hydrogen fluoride fluoridizes difluoroacetic acid, the main drawback of this method is: yield is lower; Equipment requirements is high; (3) take dichloroacetyl chloride as the operational path of Material synthesis difluoroacetic acid, the major advantage of this method is abundant raw material source, and processing condition are gentle, simple to operate, and equipment investment is low; Main drawback is that route is relatively long.
In addition, with SbF 5for catalyzer, can react by catalysis ether material, generate corresponding acyl fluorides, acyl fluorides and alcohols generation esterification obtain esters product.The catalytic efficiency of the method is high, but shortcoming is SbF 5belonging to hypertoxic type material, is very strong Lewis acid, meets water and namely produces corrosive hydrofluoric acid, high to the requirement of equipment, and expensive.
Summary of the invention
The present invention is in order to solve the problem that existing ethyl difluoro synthetic method craft process is complicated, security is low, preparation cost is higher, and then the synthetic method of a kind of ethyl difluoro proposed.
The present invention is the technical scheme taked that solves the problem: with 1,1,2,2-tetrafluoro ethyl diethyldithiocarbamate ether for raw material, under the effect of 80-100 DEG C of temperature of reaction and catalyzer, 1,1,2,2-tetrafluoro ethyl diethyldithiocarbamate ether generation oxidizing reaction generates acyl fluorides, collects be converted into ethyl ester without the need to separation condenser.Reactive chemistry formula is as follows:
Concrete steps of the present invention are:
The preparation of step one, catalyzer: the Al filling certain order number in tubular reactor 2o 3powder, guarantees Al 2o 3the height of powder, at the heating region of tube furnace, under nitrogen protection, is heated to 250-300 DEG C and keeps 12h, then continuing slowly to pass into CH af bcl cgas reacts, and temperature of reaction is 250-300 DEG C, and the reaction times is 12h;
Step 2, inspection units resistance to air loss, arrange temperature control program; By catalyzer high-temperature activation before adding raw material, activation temperature is 300 DEG C, and soak time is 3h, after activation, treats that system temperature drops to set temperature of reaction;
Step 3, ligation device, carry out in the tubular reactor of catalyzed reaction still in step one, simultaneously, connect 3 condensers, appropriate dehydrated alcohol is added respectively in condenser 1 and 2, condenser 3 does not add dehydrated alcohol, and 3 condensers are placed in the vacuum jacketed flask being placed with dry ice-alcohol mixture respectively;
Step 4, in reaction system, pass into raw material 1,1,2,2-tetrafluoro ethyl diethyldithiocarbamate ether, without nitrogen or pass into nitrogen condition under react; Controlling raw material is 5 ~ 20s by the residence time of tubular react furnace, and controlling temperature of reaction in reaction system is 70 DEG C ~ 100 DEG C, and reaction pressure is normal pressure;
After step 5, raw material have led to, continue reaction 30-60 minute.Then adjust nitrogen and pass into speed, continue through condenser and esterification is carried out to intermediates and collects esterified prod;
Step 6, the mixture in step 5 carried out washing and be separated, then thick product is carried out rectification and purification.
The invention has the beneficial effects as follows:
(1) preparation method of the present invention is 1,1,2,2-tetrafluoro ethyl diethyldithiocarbamate ether is raw material, under the effect of 70-100 DEG C of condition and catalyzer, 1,1,2,2-tetrafluoro ethyl diethyldithiocarbamate ether generation oxidizing reaction generates acyl fluorides, collects be converted into ethyl ester without the need to separation condenser.Obtain the mixture of raw material, dehydrated alcohol and ethyl difluoro.By rectification and purification, obtain the target product ethyl difluoro that purity is more than 99%.
(2) preparation method's production stage of the present invention is simple, and security is high, and the catalyzed reaction time is short.
(3) method for preparing catalyst that the present invention is used is simple, with Al 2o 3for raw material, after 250-350 DEG C of high-temperature activation, under under nitrogen protection with 250 DEG C of conditions, slowly pass into gas CH af bcl creaction, obtains lewis acid catalyst AlF xcl y.Compare conventional SbF 5catalyzer, this catalyzer uses safer, and cost is lower.
Accompanying drawing explanation
1. Fig. 1 is reaction unit schematic diagram of the present invention, 1-drying tube, 2-glass columns, 3-injection port, 4-tubular react furnace, 5-absorbent cotton, 6. ball milling mouth, 7-first condenser, 8-second condenser, 9-the 3rd condenser, 10-vacuum jacketed flask, 11-oil vacuole device in Fig. 1.
Embodiment
Embodiment one: composition graphs 1 illustrates present embodiment, described in present embodiment, a kind of synthetic method of ethyl difluoro realizes as follows:
The preparation of step one, catalyzer: the Al filling certain order number in tubular reactor 2o 3powder, guarantees Al 2o 3the height of powder, at the heating region of tube furnace, under nitrogen protection, is heated to 250-300 DEG C and keeps 12h, then continuing slowly to pass into CH af bcl cgas reacts, and temperature of reaction is 250-300 DEG C, and the reaction times is 12h;
Step 2, inspection units resistance to air loss, arrange temperature control program; By catalyzer high-temperature activation before adding raw material, activation temperature is 300 DEG C, and soak time is 3h, after activation, treats that system temperature drops to set temperature of reaction;
Step 3, ligation device, carry out in the tubular reactor of catalyzed reaction still in step one, simultaneously, connect 3 condensers, appropriate dehydrated alcohol is added respectively in condenser 1 and 2, condenser 3 does not add dehydrated alcohol, and 3 condensers are placed in the vacuum jacketed flask being placed with dry ice-alcohol mixture respectively;
Step 4, in reaction system, pass into raw material 1,1,2,2-tetrafluoro ethyl diethyldithiocarbamate ether, without nitrogen or pass into nitrogen condition under react; Controlling raw material is 5 ~ 20s by the residence time of tubular react furnace, and controlling temperature of reaction in reaction system is 70 DEG C ~ 100 DEG C, and reaction pressure is normal pressure;
After step 5, raw material have led to, continue reaction 30-60 minute.Then adjust nitrogen and pass into speed, continue through condenser and esterification is carried out to intermediates and collects esterified prod;
Step 6, the mixture in step 5 carried out washing and be separated, then thick product is carried out rectification and purification.
Embodiment two: the catalyzer in the step 2 of a kind of synthetic method of ethyl difluoro described in present embodiment is lewis acid catalyst AlFxCly.Other composition and annexation identical with embodiment one.
Embodiment three: a kind of catalyst A lF of synthetic method of ethyl difluoro described in present embodiment xcl ysynthetic method as follows:
Steps A, in tubular reactor, fill 200 object Al 2o 3powder, and Al 2o 3the height of powder is at the heating region of tube furnace;
Step B, under nitrogen protection, be heated to 250-300 DEG C and keep 12h;
Step C, continue to pass into CH af bcl c, wherein the numerical value of a, b, c is respectively 1 or 2, and a, b, c and be 4, carry out reaction 12h and obtain catalyst A lF xcl ywherein the numerical value of x, y is uncertain integer, x and y's and be 3.Other composition and annexation identical with embodiment two.
Embodiment 1:
1, catalyst A lF xcl ypreparation.
Step one, in tubular reactor, fill granularity be 200 object Al 2o 3powder 103.32g, packing height is 18.7cm, guarantees Al 2o 3the height of powder, in the heating region of tube furnace, under nitrogen protection, is heated to 250 DEG C and maintains 12h.
Step 2, in the system of above-mentioned steps one, slowly pass into CHF 2cl, temperature of reaction is 250 DEG C, and the reaction times is 12h, obtains catalyst A lF xcl y.
2, the catalyzed reaction of 1,1,2,2-tetrafluoro ethyl diethyldithiocarbamate ether.
Step one, inspection units resistance to air loss, arrange temperature control program, by catalyst A lF before adding raw material xcl yactivate at high temperature, its activation temperature is 300 DEG C, and soak time is 3h, after activation, treats that system temperature drops to set temperature of reaction.
Step 2, connection product collecting device, check the resistance to air loss of system again.Catalyzed reaction is still carried out in tubular reactor.Meanwhile, connect 3 condensers and be used for collecting intermediate product, condenser requires anhydrous.Add 16.21g dehydrated alcohol in condenser 1, add 12.33g dehydrated alcohol in condenser 2, condenser 3 does not add dehydrated alcohol, and 3 condensers are placed in the vacuum jacketed flask being placed with dry ice-alcohol mixture respectively.
Step 3, in reaction system, pass into raw material 1,1,2,2-tetrafluoro ethyl diethyldithiocarbamate ether 20.34g, react under the condition passing into nitrogen, the residence time by catalyzer controlling raw material is 10s, and temperature of reaction is 70 DEG C, and reaction pressure is normal pressure.
After step 4, raw material have led to, continue to pass into nitrogen 60 minutes, can intermediates are purged in condenser on the one hand, guarantee that catalyzed reaction is carried out more complete on the other hand.Continue through condenser carry out esterification to intermediates and collect esterified prod.Then condenser is placed room temperature 30 minutes, and weigh condenser weight now respectively.Condenser 1 increases weight 17.32g, and condenser 2 and condenser 3 all do not increase weight.
Step 5, process esterified prod.Mixed solution in condenser 1 in above-mentioned steps four and condenser 2 is merged, then uses 200ml deionized water wash twice and separatory, obtain the thick product of 15.27g.
Step 6, rectification and purification is carried out to above-mentioned isolated thick product.
Embodiment 2
1, catalyst A lF xcl ypreparation.
Step one, in tubular reactor, fill granularity be 200 object Al 2o 3powder 109.75g, packing height is 19.90cm, guarantees Al 2o 3the height of powder, in the heating region of tube furnace, under nitrogen protection, is heated to 300 DEG C and maintains 12h.
Step 2, in the system of above-mentioned steps one, slowly pass into CH 2fCl, temperature of reaction is 300 DEG C, and the reaction times is 12h, obtains catalyst A lF xcl y.
2, the catalyzed reaction of 1,1,2,2-tetrafluoro ethyl diethyldithiocarbamate ether.
Step one, inspection units resistance to air loss, arrange temperature control program, activated by catalyzer before adding raw material at high temperature, and activation temperature is 300 DEG C, and soak time is 3h, after activation, treats that system temperature drops to set temperature of reaction.
Step 2, connection product collecting device, check the resistance to air loss of system again.Catalyzed reaction is still carried out in tubular reactor.Meanwhile, connect 3 condensers and be used for collecting intermediate product, condenser requires anhydrous.Add 17.82g dehydrated alcohol in condenser 1, add 11.47g dehydrated alcohol in condenser 2, condenser 3 does not add dehydrated alcohol, and 3 condensers are placed in the vacuum jacketed flask being placed with dry ice-alcohol mixture respectively.
Step 3, pass into raw material, pass into raw material 1,1,2,2-tetrafluoro ethyl diethyldithiocarbamate ether 20.04g, react under the condition of obstructed nitrogen in reaction system, controlling raw material is 5s by the residence time of catalyzer, and temperature of reaction is 100 DEG C, and reaction pressure is normal pressure.
After step 4, raw material have led to, continue to pass into nitrogen 30 minutes, can intermediates are purged in condenser on the one hand, guarantee that catalyzed reaction is carried out more complete on the other hand.Continue through condenser carry out esterification to intermediates and collect esterified prod.Then condenser is placed room temperature 30 minutes, and weigh condenser weight now respectively.Condenser 1 increases weight 15.46g, and condenser 2 and condenser 3 all do not increase weight.
Step 5, process esterified prod.Condenser 1 in above-mentioned steps four is carried out washing and being separated, the mixed solution in condenser 1 in above-mentioned steps four and condenser 2 is merged, then use 200ml deionized water wash twice and separatory, obtain the thick product of 10.22g.
Step 6, rectification and purification is carried out to isolated thick product in above-mentioned.
Embodiment 3:
1, catalyst A lF xcl ypreparation.
Step one, in tubular reactor, fill granularity be 200 object Al 2o 3powder 98.43g, packing height is 17.35cm, guarantees Al 2o 3the height of powder, at the heating region of tube furnace, under nitrogen protection, is heated to 280 DEG C and maintains 12h.
Step 2, in the system of above-mentioned steps one, slowly pass into CHFCl 2, temperature of reaction is 280 DEG C, and the reaction times is 12h, obtains catalyst A lF xcl y.
2, the catalyzed reaction of 1,1,2,2-tetrafluoro ethyl diethyldithiocarbamate ether.
Step one, inspection units resistance to air loss, arrange temperature control program, carried out activating to realizing best catalytic effect by catalyzer before adding raw material at high temperature, its activation temperature is 280 DEG C, soak time is 3h, after activation, treats that system temperature drops to set temperature of reaction.
Step 2, connection product collecting device, check the resistance to air loss of system again.Carry out in the tubular reactor of catalyzed reaction still in step one.Meanwhile, connect 3 condensers and be used for collecting intermediate product, condenser requires anhydrous.Add 14.40g dehydrated alcohol in condenser 1, add 9.73g dehydrated alcohol in condenser 2, condenser 3 does not add dehydrated alcohol, and 3 condensers are placed in the vacuum jacketed flask being placed with dry ice-alcohol mixture respectively.
Step 3, pass into raw material, pass into raw material 1,1,2,2-tetrafluoro ethyl diethyldithiocarbamate ether 20.59g, react under the condition of obstructed nitrogen in reaction system, controlling raw material is 20s by the residence time of catalyzer, and temperature of reaction is 80 DEG C, and reaction pressure is normal pressure.
After step 4, raw material have led to, continue to pass into nitrogen 30 minutes, can intermediates are purged in condenser on the one hand, guarantee that catalyzed reaction is carried out more complete on the other hand.Continue through condenser carry out esterification to intermediates and collect esterified prod.Then condenser is placed room temperature 30 minutes, and weigh condenser weight now respectively.Condenser 1 increases weight 14.12g, and condenser 2 increases weight 0.81g, and condenser 3 does not increase weight.
Step 5, process esterified prod.Mixed solution in condenser 1 in above-mentioned steps four and condenser 2 is merged, then uses 200ml deionized water wash twice and separatory, obtain the thick product of 17.70g.
Step 6, rectification and purification is carried out to isolated thick product in above-mentioned.
The foregoing is only the preferred embodiments of the present invention, be not limited to the present invention, for a person skilled in the art, the present invention can have various modifications and variations.Within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., be all included within protection scope of the present invention.

Claims (3)

1. a synthetic method for ethyl difluoro, is characterized in that: the synthetic method of described a kind of ethyl difluoro realizes as follows:
The preparation of step one, catalyzer: the Al filling certain order number in tubular reactor and glass columns 2o 3powder, guarantees Al 2o 3the height of powder, at the heating region of tube furnace, under nitrogen protection, is heated to 250-300 DEG C and keeps 12h, then continuing slowly to pass into CH af bcl cgas reacts, and temperature of reaction is 250-300 DEG C, and the reaction times is 12h;
Step 2, inspection units resistance to air loss, arrange temperature control program; By catalyzer high-temperature activation before adding raw material, activation temperature is 300 DEG C, and soak time is 3h, after activation, treats that system temperature drops to set temperature of reaction;
Step 3, ligation device, carry out in the tubular reactor of catalyzed reaction still in step one, simultaneously, connect 3 condensers, appropriate dehydrated alcohol is added respectively in condenser 1 and 2, condenser 3 does not add dehydrated alcohol, and 3 condensers are placed in the vacuum jacketed flask being placed with dry ice-alcohol mixture respectively;
Step 4, in reaction system, pass into raw material 1,1,2,2-tetrafluoro ethyl diethyldithiocarbamate ether, without nitrogen or pass into nitrogen condition under react; Controlling raw material is 5 ~ 20s by the residence time of tubular react furnace, and controlling temperature of reaction in reaction system is 70 DEG C ~ 100 DEG C, and reaction pressure is normal pressure;
After step 5, raw material have led to, continue reaction 30-60 minute.Then adjust nitrogen and pass into speed, continue through condenser and esterification is carried out to intermediates and collects esterified prod;
Step 6, the mixture in step 5 carried out washing and be separated, then thick product is carried out rectification and purification.
2. the synthetic method of a kind of ethyl difluoro according to claim 1, is characterized in that: the catalyzer in step 2 is lewis acid catalyst AlF xcl y.
3. the synthetic method of a kind of ethyl difluoro according to claim 2, is characterized in that: catalyst A lF xcl ysynthetic method as follows:
Steps A, in tubular reactor, fill 200 object Al 2o 3powder, and Al 2o 3the height of powder is at the heating region of tube furnace;
Step B, under nitrogen protection, be heated to 250-300 DEG C and keep 12h,
Step C, continue to pass into CH af bcl c, wherein the numerical value of a, b, c is respectively 1 or 2, and a, b, c and be 4, carry out reaction 12h and obtain catalyst A lF xcl ywherein the numerical value of x, y is uncertain integer, x and y's and be 3.
CN201511033926.1A 2015-12-31 2015-12-31 Synthesizing method for ethyl difluoroacetate Pending CN105461560A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106831406A (en) * 2017-02-14 2017-06-13 中国科学院上海高等研究院 A kind of nonmetal catalyzed method and device for preparing two fluoracyl fluorides

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0694523A1 (en) * 1994-07-28 1996-01-31 Asahi Glass Company Ltd. Preparation of difluoroacetic acid fluoride and difluoroacetic acid esters
CN102471217A (en) * 2009-08-03 2012-05-23 罗地亚经营管理公司 Method for preparing difluoroacetic acid esters
CN102770405A (en) * 2010-02-22 2012-11-07 中央硝子株式会社 Method for producing difluoroacetic acid ester

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0694523A1 (en) * 1994-07-28 1996-01-31 Asahi Glass Company Ltd. Preparation of difluoroacetic acid fluoride and difluoroacetic acid esters
CN102471217A (en) * 2009-08-03 2012-05-23 罗地亚经营管理公司 Method for preparing difluoroacetic acid esters
CN102770405A (en) * 2010-02-22 2012-11-07 中央硝子株式会社 Method for producing difluoroacetic acid ester

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106831406A (en) * 2017-02-14 2017-06-13 中国科学院上海高等研究院 A kind of nonmetal catalyzed method and device for preparing two fluoracyl fluorides
CN106831406B (en) * 2017-02-14 2019-10-11 中国科学院上海高等研究院 A kind of method and device of two fluoracyl fluorides of nonmetal catalyzed preparation

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Application publication date: 20160406