Patent US4116941A successfully refreshed from Google Patents.
US4092361A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of 3,5,5-trimethyl-cyclohex-2-ene-1,4-dione
Assignee: Rhone Poulenc Industries SA
•
Filing: 1976-12-16
•
Granted: 1978-05-30
•
Expires: 1996-12-16
Abstract
Abstract 3,5,5-Trimethyl-cyclohex-2-ene-1,4-dione is prepared by a liquid phase oxidation of β-isophorone using carbon black as catalyst in the presence of a base.
Inventors
- 👤 Michel Costantini
- 👤 Adrien Dromard
- 👤 Michel Jouffret
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:01
CPC Classifications
C; C07; C07C; C07C45/00; C07C45/27; C07C45/32; C07C45/33; C07C45/34
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
48 words
In a process for the preparation of 3,5,5-trimethyl-cyclohex-2-ene-1,4-dione by oxidation of β-isophorone in the liquid phase by means of molecular oxygen or of a gas which contains molecular oxygen, the improvement consisting of carrying out said oxidation using carbon black as catalyst in the presence of a base.
Claim 2
Dependent Claim
48 words
In a process for the preparation of 3,5,5-trimethyl-cyclohex-2-ene-1,4-dione by oxidation of β-isophorone in the liquid phase by means of molecular oxygen or of a gas which contains molecular oxygen, the improvement consisting of carrying out said oxidation using carbon black as catalyst in the presence of a base.
Claim 3
Dependent Claim
23 words
A process according to claim 1, wherein the carbon black has a specific surface area of between 20 and 2,000 m 2 /g.
Claim 4
Dependent Claim
24 words
A process according to claim 1, wherein the amount of carbon black present is from 0.001 to 20% by weight of the reaction mixture.
Claim 5
Dependent Claim
34 words
A process according to claim 1, wherein the base is selected from the group consisting of an alkali metal hydroxide, carbonate or alcoholate, a quaternary ammonium hydroxide, an amine and a heterocyclic nitrogen-containing base.
Claim 6
Dependent Claim
24 words
A process according to claim 4, wherein said base is an alkylamine in which each alkyl radical contains from 1 to 8 carbon atoms.
Claim 7
Dependent Claim
13 words
A process according to claim 5, wherein said alkylamine is secondary or tertiary.
Claim 8
Dependent Claim
22 words
A process according to claim 6, wherein the alkylamine is selected from the group consisting of trimethylamine, triethylamine, diethylamine, diisopropylamine and diisobutylamine.
Claim 9
Dependent Claim
24 words
A process according to claim 1, wherein the amount of base present, expressed in mols per mol of starting β-isophorone is at least 0.01.
Claim 10
Dependent Claim
24 words
A process according to claim 8, wherein the amount of base present, expressed in mols per mol of starting β-isophorone is at least 0.01.
Claim 11
Dependent Claim
28 words
A process according to claim 1, wherein the oxidation temperature is between 0° and 100° C and the partial pressure of oxygen is between 0.1 and 50 bars.
References Cited (Backward Citations)
US3354220A
Cited
UST900015I4
Cited
US3923898A
Cited
US3931327A
Cited
US4010205A
Cited
US4026948A
Cited
US4046813A
Cited
US3960966A
Cited
US3944620A
Cited
US4026947A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-05-29 | 1981-11-28 | 1982-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-29 | 1985-11-28 | 1986-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-29 | 1989-11-28 | 1990-05-30 | $7700.00 | Window Closed / Lapsed |