Patent US4383904A successfully refreshed from Google Patents.
US4383904A
Expired / Lapsed
US
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Photochemical epoxidation
Assignee: Celanese Corp
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Filing: 1981-09-21
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Granted: 1983-05-17
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Expires: 2001-09-21
Abstract
Abstract This invention provides a process for photochemical epoxidation of olefins with molecular oxygen in a liquid phase with irradiation in the presence of a combination of 1,2-diketone photosensitizers. Propylene can be converted to propylene oxide by reaction with molecular oxygen in an ortho-dichlorobenzene reaction medium in the presence of 2,3-butanedione and 1-phenyl-1,2-propanedione photosensitizers, at a space time yield rate of at least 15 grams per liter hour.
Inventors
- 👤 James P. Shepherd
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:44
CPC Classifications
C; C07; C07D; C07D301/00; C07D301/02; C07D301/03; C07D301/04; C07D301/06; Y; Y10; Y10S; Y10S204/00; Y10S204/902; Y10S204/912
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
41 words
A process for the photochemical epoxidation of olefins which comprises oxidizing an alkene compound with molecular oxygen in liquid phase with irradiation in the presence of at least two 1,2-diketone photosensitizers which absorb light in a range between about 3700-4600 angstroms.
Claim 2
Dependent Claim
41 words
A process for the photochemical epoxidation of olefins which comprises oxidizing an alkene compound with molecular oxygen in liquid phase with irradiation in the presence of at least two 1,2-diketone photosensitizers which absorb light in a range between about 3700-4600 angstroms.
Claim 3
Dependent Claim
17 words
A process in accordance with claim 1 wherein the alkene compound contains between about 3-12 carbon atoms.
Claim 4
Dependent Claim
12 words
A process in accordance with claim 1 wherein the alkene is propylene.
Claim 5
Dependent Claim
16 words
A process in accordance with claim 1 wherein the liquid phase comprises an aprotic solvent medium.
Claim 6
Dependent Claim
16 words
A process in accordance with claim 1 wherein the liquid phase comprises an o-dichlorobenzene solvent medium.
Claim 7
Dependent Claim
16 words
A process in accordance with claim 1 wherein the liquid phase comprises an acetonitrile solvent medium.
Claim 8
Dependent Claim
32 words
A process in accordance with claim 1 wherein the quantity of photosensitizers in the reaction medium is in the range between about 0.1-40 weight percent, based on the weight of alkene compound.
Claim 9
Dependent Claim
28 words
A process in accordance with claim 1 wherein the reaction medium contains two 1,2-diketone photosensitizers, and the said photosensitizers are present in a weight ratio between about 1-10:1-10.
Claim 10
Dependent Claim
18 words
A process in accordance with claim 1 wherein the photosensitizers in the reaction medium comprise 2,3-butanedione and 1-phenyl-1,2-propanedione.
Claim 11
Dependent Claim
26 words
A process in accordance with claim 1 wherein the photochemical epoxidation is conducted at a temperature in the range between about -10° C. and 150° C.
Claim 12
Dependent Claim
20 words
A process in accordance with claim 1 wherein the photochemical epoxidation is conducted at a pressure between about 15-1500 psi.
Claim 13
Dependent Claim
27 words
A process in accordance with claim 1 wherein the epoxide product is produced at a space time yield rate of at least 15 grams per liter hour.
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) | 1986-05-16 | 1986-11-15 | 1987-05-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-05-16 | 1990-11-15 | 1991-05-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-05-16 | 1994-11-15 | 1995-05-17 | $7700.00 | Window Closed / Lapsed |