CN1365969A - Process for preparing aminoformate - Google Patents
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- CN1365969A CN1365969A CN 01106723 CN01106723A CN1365969A CN 1365969 A CN1365969 A CN 1365969A CN 01106723 CN01106723 CN 01106723 CN 01106723 A CN01106723 A CN 01106723A CN 1365969 A CN1365969 A CN 1365969A
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- reaction
- alkyl
- preparing carbamate
- alcohol
- carboxylamine
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Abstract
A process for preparing aminoformate technically features that under the existance of composite catalyst (nm-class metal oxide MnO2n and R3N) the urea or nitrogen-substituted carbamide and the C1-C6 alcohol (or biol or triol) take part in reaction to obtain C1-C6 alkyl aminoformate or C1-C6 polyol polyaminoformate. Its advantages are high selectivity and speed, and high output rate.
Description
The present invention relates to a kind of method for preparing carbamate.
Carbamate can be used as the intermediate of agricultural chemicals, medicine and organic synthesis.Traditional synthetic method mainly is to be raw material with hypertoxic phosgene, separates through alcoholysis and ammonia and obtains carbamate.In recent years, along with the development of society, various countries more and more pay attention to environment, and new synthetic method is sought all in active research by many countries, with production and the application of banning phosgene gradually.The non-phosgene process of Cai Yonging had the plain salt method of urea nitrate, carbonic ether ammonolysis process, alcoholysis of urea, alkyl chloride method, electrolytic process, nitro-compound reduction method and hydroxamic acid method etc. in the past, though these methods have been avoided the use phosgene, but urea nitrate salt method (" Organic Chemicals and intermediate brief guide " Liaoning Province petrochemical complex information master station, p287～288) the urea nitrate salt explosive that is adopted, industrial production casualty ratio of accidents height, productive rate is low, can not scale operation.Carbonic ether ammonolysis process (EP0,449,558A2) simple, but carbonic ether adopts the phosgene preparation more, and is although there was non-phosgene to produce methylcarbonate in these several years, limited with the carbamate kind of its production, alkyl chloride method (Chem.Lett.1984, (9), 1571～2) carbonic acid gas, ammonia or organic amine and alkyl chloride are under high pressure reacted, productive rate is lower.Electrolytic process (DE3,529,531) is raw material with the methane amide, and Sodium Bromide is that ionogen carries out the electrolytic synthesis carbamate, and this method productive rate is low, and energy consumption is big.Reduction method (CA.110 vol:7649) makes nitro-compound high pressure-temperature reduction in the presence of pure and mild catalyzer, obtains carbamate, severe reaction conditions, and selectivity is low, and by product is many.Alcoholysis of urea is more potential in the method for synthesizing carbamic acid ester without phosgene, but method (DE3 in the past, 200,559) need high pressure, high temperature, long reaction time, reaction preference is poor, and urea decomposition becomes ammonium carbamate to condense on the condenser on the one hand, byproducts such as also residual a large amount of biurets and trimeric cyanamide at the bottom of the reaction flask in addition, thus cause reaction yield low.Therefore, the key that improves productive rate is to select appropriate catalyst, and Japanese Patent (JP70,23,536) adopts common PbO
2Or the acetate of Pb, Cu, Zn makes catalyzer, and United States Patent (USP) (US3,574,711) adopts common ZnO to make catalyzer, and the reaction times reaches 19h.United States Patent (USP) (US3,013,064) adopts Cu (OAC)
2Make the catalyzer synthesis of carbamates, reaction pressure is up to 5-10atm, and productive rate is lower than 80%.
The objective of the invention is by screening a kind of catalyst system efficiently, in the hope of can under relatively mild reaction conditions, preparing carbamate, and improve the carbamate productive rate, overcome the deficiencies in the prior art.
Be described in detail the preparation method of carbamate of the present invention below.
With nanosize metal oxide M
nO
mAnd R
3N makes urea or nitrogen replace urea and C as the composite catalyst of reaction
1-C
6The alcohol reaction of 1-3 unit, make carboxylamine C
1-C
6Alkyl ester or C
1-C
6The polyvalent alcohol multiple-amino ester formate, the carboxylamine C that makes
1-C
4The same C of alkyl ester
6-C
301-3 unit alcohol is at catalyzer Ti (OR)
4Carry out transesterification reaction under the catalysis, generate carboxylamine C
6-C
30Alkyl ester or C
6-C
30The polyvalent alcohol multiple-amino ester formate, Ti (OR)
4Middle R is C
1-C
6Alkyl.These amino formate compounds general structures are:
R=alkyl, cycloalkyl, unsaturated alkyl, aryl; R '=H, alkyl, cycloalkyl, unsaturated alkyl, aryl; N=2～10.
It is nanosize metal oxide M that urea or nitrogen replace the used catalyzer of urea alcoholysis
nO
m, M
nO
mBe preferably TiO
2, ZnO, PbO
2, ZrO, CuO, Cu
2O, caO, MgO, Fe
2O
3, Fe
3O
4, MnO or CoO, preferably select CuO, ZnO or PbO
2R
3N plays synergy in reaction, R is preferably C
1-C
18Alkyl, aryl or hydroxyalkyl, more preferably C
2-C
4Alkyl or hydroxyethyl.If adopt C
1-C
3When monohydroxy-alcohol is raw material, need be added in polar material stable under the reaction conditions and makes solvent, make carboxylamine C
1-C
3Alkyl ester, stable polar solvent is dimethyl formamide, diethylformamide, N-Methyl pyrrolidone under reaction conditions, N-ethyl pyrrolidone, methyl-sulphoxide or tetramethylene sulfone.
The selected catalyzer of the transesterification reaction of carbamate is Ti (OR)
4, R is C
1-C
6Alkyl is preferably selected C
3-C
4Alkyl, temperature of reaction are 140～180 ℃, and the reaction times is that 1～6h gets final product.The carbamate of lower alcohol and higher alcohols almost can quantitatively react, and generate the carbamate of higher alcohols, have very high productive rate.Reaction formula is as follows:
The ratio of components of the transesterification reaction of carbamate (mol ratio) is: the positive butyl ester of carboxylamine: alcohol=1: 0.33～1 is 1: 0.33 for the trivalent alcohol proportioning, is 1: 0.5 for the dibasic alcohol proportioning, is 1: 1 for the monohydroxy-alcohol proportioning.
The ratio of components (mol ratio) that urea or nitrogen replace the urea alcoholysis reaction is that urea or nitrogen replace urea: alcohol=1: 1～5, and temperature of reaction is 115～145 ℃, the reaction times is 4～10h.
Advantage of the present invention and positively effect: the present invention has adopted nanosize metal oxide as catalyzer, has improved the selectivity and the speed of response of reaction, and reaction need not pressurization, and lesser temps can be finished under normal pressure, and the reaction times is short.And at cocatalyst R
3Under the effect of N, reaction generates carbamate to the intermediate isocyanic acid of generation with alcohol rapidly, has suppressed the generation of by product, has improved reaction yield.At synthetic C
1-C
3During carbamate, because C
1-C
3The alcohol boiling point is low, reach temperature of reaction, according to technology (JP71 in the past, 06,042) must add higher stress reaction, the present invention selects a kind of polar solvent stable under reaction conditions for use, make to be reflected under the normal pressure and carry out, synthetic these carbamates that can be more convenient.
Below according to the further narration implementation procedure of the present invention of embodiment, present embodiment is in order to be better to understand the present invention, and can not limit the present invention.
Embodiment 1 synthesizing glycol list ether carbamate
In the four-hole bottle of the 250mL that agitator, condenser and thermometer are housed, add urea 45g (0.75mol), ethylene glycol monoethyl ether 135g (1.5mol), nano level ZnO 0.9g and trolamine 0.9g.Stir, be heated to backflow.And control reaction temperature is at 140 ℃, tail gas NH
3Absorb with dilute sulphuric acid or water.Behind the reaction 8h, reaction mixture is gone to matrass,, collect front-end volatiles ethylene glycol monoethyl ether 70g and product ethylene glycol monoethyl ether carbamate 91.7g respectively, productive rate 91.9%, 56～58 ℃ of mp in the 0.01Pa underpressure distillation.Residue 4.8g at the bottom of the matrass.
Controlled trial: use common ZnO instead and make catalyzer in above-mentioned test, all the other conditions are identical, get ethylene glycol monoethyl ether carbamate 75.2g, productive rate 75.3%.Residue 13.2g at the bottom of the matrass.
Embodiment 2 synthesizing amino n-buty formates
In the four-hole bottle of the 250mL that agitator, condenser and thermometer are housed, add urea 45g (0.75mol), propyl carbinol 111g (1.5mol), nano level TiO
21.5g and trolamine 0.9g.Stir, be heated to backflow.Along with the carrying out of reaction, temperature constantly rises, and when temperature of reaction rose to 140 ℃, reaction was finished, and needed about 8h approximately.Subsequently reaction mixture is gone to matrass, in the 0.01Pa underpressure distillation, collect the positive butyl ester 83.1g of front-end volatiles propyl carbinol 59g and product carboxylamine respectively, productive rate 94.7%, 53～54 ℃ of mp.Residue 3.6g at the bottom of the matrass.
Controlled trial: in above-mentioned test, use general T iO instead
2Make catalyzer, all the other conditions are identical, get the positive butyl ester 61.26g of carboxylamine, productive rate 70.2%.Residue 11.2g at the bottom of the matrass.
The embodiment 3 synthetic positive butyl esters of N-phenylcarbamic acid
In the four-hole bottle of the 250mL that agitator, condenser and thermometer are housed, add single phenyl urea 68g (0.5mol), propyl carbinol 74g (1mol), nano level PbO
21.6g and trolamine 0.9g.Stir, be heated to backflow.Along with the carrying out of reaction, temperature constantly rises, and when temperature of reaction rose to 140 ℃, reaction was finished, and needed about 14h approximately.Subsequently reaction mixture is gone to matrass, in the 0.01Pa underpressure distillation, collect the positive butyl ester 80g of front-end volatiles propyl carbinol 36.5g and N-phenylcarbamic acid respectively, productive rate 82.9%, 60～61 ℃ of mp.Residue 11.6g at the bottom of the matrass.
Embodiment 4 synthesizing amino formic acid n-propyls
In the four-hole bottle of the 250mL that agitator, condenser and thermometer are housed, add urea 30g (0.5mol), n-propyl alcohol 39g (0.65mol), N-Methyl pyrrolidone 50g, nano level CuO 0.6g and trolamine 0.6g.Stir, be heated to backflow.Along with the carrying out of reaction, temperature constantly rises, and behind reaction 5h, adds n-propyl alcohol 20g, continues back flow reaction, and when temperature rose to 140 ℃, reaction was finished, and needed about 10h approximately.Subsequently reaction mixture is gone to matrass,, collect front-end volatiles n-propyl alcohol 32g and product carboxylamine n-propyl 38.2g respectively, productive rate 74.2%, mp59.5～60.5 ℃ in the 0.01Pa underpressure distillation.Residue 10.6g at the bottom of the matrass.
The just own ester of embodiment 5 synthesizing amino formic acid
In the four-hole bottle of the 250mL that agitator, thermometer and water distilling apparatus are housed, add the positive butyl ester 58.5g of carboxylamine (0.5mol) of embodiment 2 preparations, n-hexyl alcohol 51g (0.5mol), Ti (OBu)
40.6g.Stir, be heated to 170 ℃, constantly steam the propyl carbinol of generation, behind the 2.5h, reaction finishes.Steam propyl carbinol 36.6g altogether, get the just own ester 71.5g of carboxylamine, productive rate 98.6%, 65～66 ℃ of mp.
Embodiment 6 synthetic hexylene glycols-1, the 6-diurethanes
In the four-hole bottle of the 250mL that agitator, thermometer and water distilling apparatus are housed, add the positive butyl ester 70.2g of carboxylamine (0.6mol) of embodiment 2 preparations, hexylene glycol-1,6 35.4g (0.3mol), Ti (OBu)
40.7g.Stir, be heated to 170 ℃, constantly steam the propyl carbinol of generation, behind the 2.5h, reaction finishes.Steam propyl carbinol 43.6g altogether, get hexylene glycol-1,6-diurethanes 58.8g, productive rate 96.1%, 202～204 ℃ of mp.
Embodiment 7 synthesizing amino formic acid octadecyl esters
In the four-hole bottle of the 250mL that agitator, thermometer and water distilling apparatus are housed, add the positive butyl ester 58.5g of carboxylamine (0.5mol) of embodiment 2 preparations, stearyl alcohol 135g (0.5mol), Ti (OBu)
40.6g.Stir, be heated to 170 ℃, constantly steam the propyl carbinol of generation, behind the 2.5h, reaction finishes.Steam propyl carbinol 36.0g altogether, get the just own ester 143.5g of carboxylamine, productive rate 91.7%, 94～95 ℃ of mp.
Embodiment 8 synthetic glycol ether diurethaness
In the four-hole bottle of the 250mL that agitator, thermometer and water distilling apparatus are housed, add the positive butyl ester 70.2g of carboxylamine (0.6mol) of embodiment 2 preparations, glycol ether 31.8g (0.3mol), Ti (OBu)
40.7g.Stir, be heated to 170 ℃, constantly steam the propyl carbinol of generation, behind the 2.5h, reaction finishes.Steam propyl carbinol 41.3g altogether, get glycol ether diurethanes 51.3g, productive rate 89.1%, 146～148 ℃ of mp.
Embodiment 9 synthesizing amino cyclohexyl formates
In the four-hole bottle of the 250mL that agitator, thermometer and water distilling apparatus are housed, add the positive butyl ester 58.5g of carboxylamine (0.5mol) of embodiment 2 preparations, hexalin 50g (0.5mol), Ti (OBu)
40.6g.Stir, be heated to 170 ℃, constantly steam the propyl carbinol of generation, behind the 2.5h, reaction finishes.Steam propyl carbinol 37.1g altogether, get carboxylamine cyclohexyl 70.5g, productive rate 98.6%, 108～109 ℃ of mp.
Embodiment 10 synthesizing amino benzyl formates
In the four-hole bottle of the 250mL that agitator, thermometer and water distilling apparatus are housed, add the positive butyl ester 58.5g of carboxylamine (0.5mol) of embodiment 2 preparations, benzylalcohol 54g (0.5mol), Ti (OBu)
40.6g.Stir, be heated to 170 ℃, constantly steam the propyl carbinol of generation, behind the 2.5h, reaction finishes.Steam propyl carbinol 36.4g altogether, get benzyl carbamate 69.0g, productive rate 91.4%, 87～88 ℃ of mp.
Claims (9)
1, a kind of method for preparing carbamate is characterized in that: with nanosize metal oxide M
nO
mAnd R
3N makes urea or nitrogen replace urea and C as the composite catalyst of reaction
1-C
6The alcohol reaction of 1-3 unit, make carboxylamine C
1-C
6Alkyl ester or C
1-C
6The polyvalent alcohol multiple-amino ester formate.
2, the method for preparing carbamate according to claim 1 is characterized in that: the carboxylamine C that makes
1-C
4The same C of alkyl ester
6-C
301-3 unit alcohol is at catalyzer Ti (OR)
4Carry out transesterification reaction under the catalysis, generate carboxylamine C
6-C
30Alkyl ester or C
6-C
30The polyvalent alcohol multiple-amino ester formate, Ti (OR)
4Middle R is C
1-C
6Alkyl.
3, the method for preparing carbamate according to claim 1 is characterized in that: nanosize metal oxide M
nO
mBe preferably TiO
2, ZnO, PbO
2, ZrO, CuO, Cu
2O, CaO, MgO, Fe
2O
3, Fe
3O
4, MnO or CoO.
4, the method for preparing carbamate according to claim 3 is characterized in that: nanosize metal oxide M
nO
mMore preferably CuO, ZnO or PbO
2
5, the method for preparing carbamate according to claim 1 is characterized in that: R
3R is preferably C among the N
1-C
18Alkyl, aryl or hydroxyalkyl.
6, the method for preparing carbamate according to claim 5, it is characterized in that: R preferably selects C
2-C
4Alkyl or hydroxyethyl.
7, the method for preparing carbamate according to claim 1 is characterized in that: if adopt C
1-C
3When monohydroxy-alcohol is raw material, need be added in polar material stable under the reaction conditions and makes solvent, make carboxylamine C
1-C
3Alkyl ester.
8, according to the described method for preparing carbamate of claim 7, it is characterized in that: stable polar solvent is dimethyl formamide, diethylformamide, N-Methyl pyrrolidone under reaction conditions, N-ethyl pyrrolidone, methyl-sulphoxide or tetramethylene sulfone.
9, the method for preparing carbamate according to claim 2 is characterized in that: catalyzer Ti (OR)
4, preferred R is C
3-C
4Alkyl.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB011067233A CN1173939C (en) | 2001-01-16 | 2001-01-16 | Process for preparing aminoformate |
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|---|---|---|---|
| CNB011067233A CN1173939C (en) | 2001-01-16 | 2001-01-16 | Process for preparing aminoformate |
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|---|---|
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| CN1173939C CN1173939C (en) | 2004-11-03 |
Family
ID=4655698
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE112009000127T5 (en) | 2008-02-26 | 2010-12-30 | Bayer Materialscience Ag | Catalyst for the synthesis of alkyl carbamates, process for its preparation and its use |
| DE102010013992A1 (en) | 2009-04-14 | 2013-05-23 | Bayer Materialscience Aktiengesellschaft | A method for producing a carbamate, a catalyst used in the method, a method for producing the catalyst and its use |
| CN103172541A (en) * | 2011-12-23 | 2013-06-26 | 中国科学院兰州化学物理研究所 | Clean synthesis method of phenyl carbamate |
| CN105102422A (en) * | 2013-03-29 | 2015-11-25 | 旭化成化学株式会社 | Method for producing isocyanate |
| CN106397271A (en) * | 2016-08-31 | 2017-02-15 | 中国科学院兰州化学物理研究所 | Method for synthesis of N-substituted dicarbamate with urea as carbonyl source |
| CN109337067A (en) * | 2013-07-31 | 2019-02-15 | 陶氏环球技术有限责任公司 | The preparation method of polyurethanes and its reaction product |
| CN111662215A (en) * | 2020-07-27 | 2020-09-15 | 重庆化工职业学院 | Process for preparing carbamates |
| CN115108943A (en) * | 2022-08-09 | 2022-09-27 | 山东禹城易澳科技有限公司 | Process for stabilizing water temperature of hot water in carbamate production |
-
2001
- 2001-01-16 CN CNB011067233A patent/CN1173939C/en not_active Expired - Fee Related
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE112009000127T5 (en) | 2008-02-26 | 2010-12-30 | Bayer Materialscience Ag | Catalyst for the synthesis of alkyl carbamates, process for its preparation and its use |
| US8338634B2 (en) | 2008-02-26 | 2012-12-25 | Bayer Materialscience Ag | Catalyst for the synthesis of alkyl carbamates, the method for preparing the same and the use thereof |
| DE102010013992A1 (en) | 2009-04-14 | 2013-05-23 | Bayer Materialscience Aktiengesellschaft | A method for producing a carbamate, a catalyst used in the method, a method for producing the catalyst and its use |
| US8450518B2 (en) | 2009-04-14 | 2013-05-28 | Bayer Materialscience Ag | Method for preparing a carbamate, a catalyst applied in the method, a method for preparing the catalyst and use thereof |
| CN103172541A (en) * | 2011-12-23 | 2013-06-26 | 中国科学院兰州化学物理研究所 | Clean synthesis method of phenyl carbamate |
| CN105102422B (en) * | 2013-03-29 | 2018-01-09 | 旭化成株式会社 | The manufacture method of isocyanates |
| US9714215B2 (en) | 2013-03-29 | 2017-07-25 | Asahi Kasei Chemicals Corporation | Method for producing isocyanate |
| CN107266338A (en) * | 2013-03-29 | 2017-10-20 | 旭化成株式会社 | The manufacture method of isocyanates |
| CN105102422A (en) * | 2013-03-29 | 2015-11-25 | 旭化成化学株式会社 | Method for producing isocyanate |
| CN107266338B (en) * | 2013-03-29 | 2019-10-11 | 旭化成株式会社 | The manufacturing method of isocyanates |
| CN109337067A (en) * | 2013-07-31 | 2019-02-15 | 陶氏环球技术有限责任公司 | The preparation method of polyurethanes and its reaction product |
| CN106397271A (en) * | 2016-08-31 | 2017-02-15 | 中国科学院兰州化学物理研究所 | Method for synthesis of N-substituted dicarbamate with urea as carbonyl source |
| CN111662215A (en) * | 2020-07-27 | 2020-09-15 | 重庆化工职业学院 | Process for preparing carbamates |
| CN115108943A (en) * | 2022-08-09 | 2022-09-27 | 山东禹城易澳科技有限公司 | Process for stabilizing water temperature of hot water in carbamate production |
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|---|---|
| CN1173939C (en) | 2004-11-03 |
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