US4501915A
Expired / Lapsed
US
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Preparation of N-alkyl-monosubstituted carbamates
Assignee: Lyondell Chemical Technology LP
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Filing: 1980-07-30
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Granted: 1985-02-26
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Expires: 2000-07-30
Abstract
Abstract An improved process for the preparation of N-alkyl-monosubstituted carbamates by reacting an aliphatic primary amine, urea and a monohydric aliphatic alcohol in the presence of a strongly basic tertiary amine catalyst and optionally an inert solvent.
Inventors
- 👤 John J. McCoy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 20:50
CPC Classifications
C; C07; C07C; C07C269/00; C07C269/04
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
128 words
A process for the preparation of an alkyl-N-monosubstituted carbamic acid ester which comprises reacting an aliphatic primary amine having the formula RNH 2 wherein R is a straight or branched chain alkyl group containing from 1 to 18 carbon atoms, with urea and at least a stoichiometric amount of a monohydric aliphatic alcohol, based on the aliphatic amine and, having from 1 to 18 carbon atoms at a temperature in the range of from about 125° C. to 250° C. in the presence of a catalytic amount of a tertiary amine containing from 1 to 18 carbon atoms and selected from the group consisting of trialkylamines wherein the alkyl groups are the same, triphenylamine, n-dodecyldimethylamine, n-tetradecyldimethylamine, n-hexyldecyldimethylamine, n-octyldecyldimethylamine, N,N,N',N'-tetramethylethylenediamine, 1,4-diazabicyclo[2.2.2]octane, 4(N,N-dimethylamino)pyridine, pyridine, 1,5-diazabicyclo[4.3.0]non-5-ene, 1,8-diazabicyclo[5.4.0]undec-7-ene; methyldiethylamine, butyldimethylamine and benzyldimethylamine.
Claim 2
Dependent Claim
128 words
A process for the preparation of an alkyl-N-monosubstituted carbamic acid ester which comprises reacting an aliphatic primary amine having the formula RNH 2 wherein R is a straight or branched chain alkyl group containing from 1 to 18 carbon atoms, with urea and at least a stoichiometric amount of a monohydric aliphatic alcohol, based on the aliphatic amine and, having from 1 to 18 carbon atoms at a temperature in the range of from about 125° C. to 250° C. in the presence of a catalytic amount of a tertiary amine containing from 1 to 18 carbon atoms and selected from the group consisting of trialkylamines wherein the alkyl groups are the same, triphenylamine, n-dodecyldimethylamine, n-tetradecyldimethylamine, n-hexyldecyldimethylamine, n-octyldecyldimethylamine, N,N,N',N'-tetramethylethylenediamine, 1,4-diazabicyclo[2.2.2]octane, 4(N,N-dimethylamino)pyridine, pyridine, 1,5-diazabicyclo[4.3.0]non-5-ene, 1,8-diazabicyclo[5.4.0]undec-7-ene; methyldiethylamine, butyldimethylamine and benzyldimethylamine.
Claim 3
Dependent Claim
22 words
A process according to claim 1 wherein the aliphatic primary amine is selected from the group consisting of ethylamine, n-octylamine and n-dodecylamine.
Claim 4
Dependent Claim
13 words
A process according to claim 2 wherein the aliphatic primary amine is n-octylamine.
Claim 5
Dependent Claim
26 words
A process according to claim 1 wherein the molar ratio of aliphatic primary amine to urea employed in the reaction is between about 10:1 to 0.1:1.
Claim 6
Dependent Claim
15 words
A process according to claim 4 wherein the molar ratio is between 5:1 to 0.25:1.
Claim 7
Dependent Claim
23 words
A process according to claim 1 wherein the monohydric aliphatic alcohol is selected from the group consisting of methanol, ethanol, decanol, and n-octanol.
Claim 8
Dependent Claim
11 words
A process according to claim 6 wherein the alcohol is methanol.
Claim 9
Dependent Claim
11 words
A process according to claim 6 wherein the alcohol is ethanol.
Claim 10
Dependent Claim
27 words
A process according to claim 1 wherein the alcohol is employed at a molar ratio of from about 1:1 to 15:1 based on the aliphatic primary amine.
Claim 11
Dependent Claim
31 words
A process according to claim 1 wherein the tertiary amine catalyst is employed in an amount of from about 0.1 to 200 mole percent based on the aliphatic primary amine employed.
Claim 12
Dependent Claim
22 words
A process according to claim 10 wherein the tertiary amine is employed in an amount of from 1 to 100 mole percent.
Claim 13
Dependent Claim
22 words
A process according to claim 1 wherein the tertiary amine catalyst is selected from the group consisting of triethylamine, trioctylamine, and pyridine.
Claim 14
Dependent Claim
13 words
A process according to claim 12 wherein the tertiary amine catalyst is triethylamine.
Claim 15
Dependent Claim
13 words
A process according to claim 12 wherein the tertiary amine catalyst is pyridine.
Claim 16
Dependent Claim
11 words
A process according to claim 1 wherein the catalyst is 1,8-diazabicyclo[5.4.0]undec-7-ene.
Claim 17
Dependent Claim
11 words
A process according to claim 1 wherein the catalyst is 1,5-diazabicyclo[4.3.0]non-5-ene.
Claim 18
Dependent Claim
22 words
A process according to claim 1 wherein the reaction temperature is in the range of from about 175° C. to 225° C.
Claim 19
Dependent Claim
21 words
A process according to claim 1 wherein the reaction is carried out under a pressure of from 1 to 50 atmospheres.
Claim 20
Dependent Claim
19 words
A process according to claim 1 wherein the reaction is carried out in the presence of an inert solvent.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-26 | 1988-08-27 | 1989-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-26 | 1992-08-27 | 1993-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-26 | 1996-08-27 | 1997-02-26 | $7700.00 | Window Closed / Lapsed |