Patent US4229591A successfully refreshed from Google Patents.
US4229591A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing a diester of oxalic acid in the gaseous phase
Assignee: Ube Corp
•
Filing: 1978-08-31
•
Granted: 1980-10-21
•
Expires: 1998-08-31
Abstract
Abstract A process for preparing a diester of oxalic acid which comprises bringing carbon monoxide into contact with an ester of nitrous acid or with an alcohol and a nitrogen oxide or a hydrate of the nitrogen oxide in the gaseous phase in the presence of a solid catalyst containing metallic palladium or a salt thereof, a gas containing molecular oxygen being introduced into the reaction system in cases where said nitrogen oxide or a hydrate of the nitrogen oxide requires molecular oxygen together with the alcohol to form an ester of nitrous acid.
Inventors
- 👤 Kenji Nishimura
- 👤 Kozo Fujii
- 👤 Keigo Nishihira
- 👤 Masaoki Matsuda
- 👤 Shinichiro Uchiumi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:58
CPC Classifications
C; C07; C07C; C07C67/00; C07C67/36; C07C68/00
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
106 words
A process for preparing a diester of oxalic acid which comprises contacting an ester of nitrous acid with carbon monoxide in the gaseous phase under ambient or reduced pressure in the presence of a solid catalyst containing metallic palladium or a salt thereof at a temperature of 50° to 200° C., and ester of nitrous acid being an ester of nitrous acid with an alcohol having 1 to 8 carbon atoms selected from the group consisting of a saturated monohydric alphatic alcohol and an alicyclic alcohol, to produce the diester of oxalic acid containing the same ester group as that of said ester of nitrous acid.
Claim 2
Dependent Claim
106 words
A process for preparing a diester of oxalic acid which comprises contacting an ester of nitrous acid with carbon monoxide in the gaseous phase under ambient or reduced pressure in the presence of a solid catalyst containing metallic palladium or a salt thereof at a temperature of 50° to 200° C., and ester of nitrous acid being an ester of nitrous acid with an alcohol having 1 to 8 carbon atoms selected from the group consisting of a saturated monohydric alphatic alcohol and an alicyclic alcohol, to produce the diester of oxalic acid containing the same ester group as that of said ester of nitrous acid.
Claim 3
Dependent Claim
18 words
The process of claim 1, wherein a gas containing molecular oxygen is added to the gaseous reaction mixture.
Claim 4
Dependent Claim
35 words
The process of claim 1, wherein an alcohol having 1 to 8 carbon atoms selected from the group consisting of a saturated monohydric alcohol and an alicyclic alcohol is added to the gaseous reaction mixture
References Cited (Backward Citations)
DE2733730A1
Cited
US4138587A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-10-21 | 1984-04-21 | 1984-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-21 | 1988-04-21 | 1988-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-21 | 1992-04-21 | 1992-10-21 | $7700.00 | Window Closed / Lapsed |