Patent US4228102A successfully refreshed from Google Patents.
US4228102A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of carboxylic acid amides
Assignee: Roehm GmbH Darmstadt
•
Filing: 1979-02-23
•
Granted: 1980-10-14
•
Expires: 1999-02-23
Abstract
Abstract What is disclosed is a method for making amides of the formula ##STR1## wherein R 1 is hydrogen or methyl, R 3 is straight-chain or branched alkyl or unsubstituted or substituted aryl, and R 4 is hydrogen or straight-chain or branched unsubstituted or substituted alkyl, which comprises reacting an ester of the formula ##STR2## wherein R 2 is alkyl having 1 to 6 carbon atoms, with heating and under autogenous pressure, in a homogeneous phase, with an amine of the formula ##STR3## said amine being present in an amount which is stoichiometrically deficient up to an amount which is in small stoichiometric excess with respect to said ester.
Inventors
- 👤 Siegmund Besecke
- 👤 Wolfgang Gaenzler
- 👤 Guenter Schroeder
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:32
CPC Classifications
C; C07; C07C; C07C231/00; C07C231/02
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
192 words
A method for making an amide of the formula ##STR9## wherein R 1 is hydrogen or methyl, R 4 is hydrogen, straight-chain or branched alkyl, or straight-chain or branched alkyl substituted by carboxy, alkoxycarbonyl, (alkyl)carbamoyl, sulfo, sulfoamido, or (alkyl)amino, and R 3 is --AX, wherein A is --(CR 5 R 6 ) n , phenylene, or naphthalene, R 5 is hydrogen or alkyl having 1 to 6 carbon atoms, R 6 is hydroxy or alkyl having 1 to 6 carbon atoms, X is hydrogen, carboxy, alkoxycarbonyl, (alkyl)carbamoyl, sulfo, sulfoamido, or (alkyl)amino and n is a whole number from 1 to 18 if X is other than (alkyl)amino or is a whole number from 2 to 18 if X is alkylamino, which method comprises reacting an ester of the formula ##STR10## wherein R 2 is alkyl having 1 to 6 carbon atoms, with heating and under pressure, in a homogeneous phase in the presence of a catalytic concentration of protons, with an amine of the formula ##STR11## said amine being present in an amount which is stoichiometrically deficient up to an amount which is in small stoichiometric excess with respect to said ester.
Claim 2
Independent Claim
192 words
A method for making an amide of the formula ##STR9## wherein R 1 is hydrogen or methyl, R 4 is hydrogen, straight-chain or branched alkyl, or straight-chain or branched alkyl substituted by carboxy, alkoxycarbonyl, (alkyl)carbamoyl, sulfo, sulfoamido, or (alkyl)amino, and R 3 is --AX, wherein A is --(CR 5 R 6 ) n , phenylene, or naphthalene, R 5 is hydrogen or alkyl having 1 to 6 carbon atoms, R 6 is hydroxy or alkyl having 1 to 6 carbon atoms, X is hydrogen, carboxy, alkoxycarbonyl, (alkyl)carbamoyl, sulfo, sulfoamido, or (alkyl)amino and n is a whole number from 1 to 18 if X is other than (alkyl)amino or is a whole number from 2 to 18 if X is alkylamino, which method comprises reacting an ester of the formula ##STR10## wherein R 2 is alkyl having 1 to 6 carbon atoms, with heating and under pressure, in a homogeneous phase in the presence of a catalytic concentration of protons, with an amine of the formula ##STR11## said amine being present in an amount which is stoichiometrically deficient up to an amount which is in small stoichiometric excess with respect to said ester.
Claim 3
Dependent Claim
20 words
A method as in claim 1 wherein the ester and amine are reacted at a temperature above about 150° C.
Claim 4
Dependent Claim
18 words
A method as in claim 2 wherein said temperature is between about 180° C. and about 250° C.
Claim 5
Dependent Claim
13 words
A method as in claim 1 wherein said protons are present as HCl.
Claim 6
Dependent Claim
29 words
A method as in claim 1 wherein the reaction is carried out in the additional presence of a stabilizer selected from the group consisting of iron, copper, and hydroquinone.
Claim 7
Dependent Claim
11 words
A method as in claim 4 wherein said stabilizer is iron.
Claim 8
Dependent Claim
15 words
A method as in claim 4 wherein said iron is present as a ferric compound.
Claim 9
Dependent Claim
25 words
A method as in claim 1 wherein R 4 is hydrogen or straight-chain or branched alkyl and R 3 is --AX wherein X is hydrogen.
Claim 10
Dependent Claim
39 words
A method as in claim 1 wherein R 4 is hydrogen or straight-chain or branched alkyl having 1 to 18 carbon atoms and R 4 is straight-chain or branched alkyl having 1 to 18 carbon atoms, phenyl, or naphthyl.
Claim 11
Dependent Claim
22 words
A method as in claim 1 wherein R 4 is hydrogen and R 3 is alkyl having 1 to 4 carbon atoms.
References Cited (Backward Citations)
DE752481C
Cited
US2451436A
Cited
US2683741A
Cited
US2529838A
Cited
US2719175A
Cited
US3878247A
Cited
US3945970A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-10-14 | 1984-04-14 | 1984-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-14 | 1988-04-14 | 1988-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-14 | 1992-04-14 | 1992-10-14 | $7700.00 | Window Closed / Lapsed |