Patent US4283564A successfully refreshed from Google Patents.
US4283564A
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Process for preparing methacrolein
Assignee: Hoechst AG
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Filing: 1979-12-21
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Granted: 1981-08-11
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Expires: 1999-12-21
Abstract
Abstract A process for preparing methacrolein by catalytic reaction of propionaldehyde with formaldehyde is disclosed wherein the catalyst comprises a mixture of secondary amine and organic carboxylic acid with up to 8 carbon atoms.
Inventors
- 👤 Wolfgang Bernhagen
- 👤 Hanswilhelm Bach
- 👤 Eike Brundin
- 👤 Wilhelm Gick
- 👤 Helmut Springer
- 👤 Adolf Hack
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 12:51
CPC Classifications
C; C07; C07C; C07C45/00; C07C45/61; C07C45/67; C07C45/68; C07C45/72; C07C45/75
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
91 words
In a process for preparing methacrolein by catalytic reaction between propionaldehyde and formaldehyde, the improvement wherein said catalyst is a mixture of a secondary amine and an organic carboxylic acid with up to 8 carbon atoms selected from the group consisting of formic acid, acetic acid, propionic acid, n-butanoic acid, i-butanoic acid, oxalic acid, maleic acid, acetylene dicarboxylic acid, malonic acid, glutaric acid, succinic acid, tartaric acid, adipic acid, hydroxy succinic acid, salicylic acid and 2-ethylhexanoic acid and the process is carried out at a temperature of 70° to 120° C.
Claim 2
Dependent Claim
91 words
In a process for preparing methacrolein by catalytic reaction between propionaldehyde and formaldehyde, the improvement wherein said catalyst is a mixture of a secondary amine and an organic carboxylic acid with up to 8 carbon atoms selected from the group consisting of formic acid, acetic acid, propionic acid, n-butanoic acid, i-butanoic acid, oxalic acid, maleic acid, acetylene dicarboxylic acid, malonic acid, glutaric acid, succinic acid, tartaric acid, adipic acid, hydroxy succinic acid, salicylic acid and 2-ethylhexanoic acid and the process is carried out at a temperature of 70° to 120° C.
Claim 3
Dependent Claim
46 words
A process according to claim 1 wherein the catalyst comprises 0.005 to 0.1 mole of a secondary amine and 0.002 to 0.05 mole of a carboxylic acid containing up to 8 carbon atoms, the molar amounts in each case referring to the amount of propionaldehyde used.
Claim 4
Dependent Claim
15 words
A process according to claim 1 wherein the reaction pressure is 2 to 10 atmospheres.
Claim 5
Dependent Claim
15 words
A process according to claim 1 wherein the reaction temperature is 95° to 110° C.
Claim 6
Dependent Claim
15 words
A process according to claim 3 wherein the reaction pressure is 2 to 4 atmospheres.
Claim 7
Dependent Claim
16 words
A process according to claim 1 wherein the secondary amine is a C 1-8 secondary amine.
Claim 8
Dependent Claim
25 words
A process according to claim 6 wherein said amine is di-n-butyl amine, dipropylamine, methylbutyl amine, ethylbutyl amine, di-2-ethylhexylamine, diphenylamine, dicyclohexylamine, piperidine, pyrolidine, piperazine or morpholine.
Claim 9
Dependent Claim
15 words
A process according to claim 1 wherein the process is conducted in the liquid phase.
Claim 10
Dependent Claim
14 words
Process according to claim 1 wherein the reaction temperature is 70° to 110° C.
Claim 11
Dependent Claim
14 words
Process according to claim 9 wherein the process is conducted in the liquid phase.
Claim 12
Dependent Claim
14 words
Process according to claim 9 wherein the process is conducted in the gas phase.
Claim 13
Dependent Claim
17 words
Process according to claim 9 wherein the process is carried out in the presence of a solvent.
Claim 14
Dependent Claim
19 words
Process according to claim 12 wherein said solvent is selected from the group consisting of 2-ethylhexanol, isododecane and toluene.
Claim 15
Dependent Claim
93 words
Process according to claim 9 wherein the process is carried out at a pressure of 2 to 10 atmospheres, the catalyst comprises 0.005 to 0.1 mol of the secondary amine and 0.002 to 0.05 mol of a carboxylic acid selected from the group consisting of formic acid, acetic acid, propionic acid, n- or i-butanoic acid, maleic acid, oxalic acid, acetylene dicarboxylic acid, malonic acid, glutaric acid, succinic acid, tartaric acid, adipic acid, hydroxy succinic acid, salicyclic acid and 2-ethylhexanoic acid, the molar amounts in each case referring to the amount of propionaldehyde used.
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) | 1984-08-10 | 1985-02-09 | 1985-08-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-08-10 | 1989-02-09 | 1989-08-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-08-10 | 1993-02-09 | 1993-08-11 | $7700.00 | Window Closed / Lapsed |