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Patent US4143052A successfully refreshed from Google Patents.
US4143052A
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Process for preparing thiophenes
Assignee: Societe Nationale Elf Aquitaine Production SA
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Filing: 1977-12-15
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Granted: 1979-03-06
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Expires: 1997-12-15
Abstract
Abstract Preparation of a thiophene by the action of H 2 S on an organic substance containing oxygen or sulphur. The substance which is used is an unsaturated carbonyl or thiocarbonyl compound, particularly an aldehyde, thioaldehyde, ketone or thioketone. The reaction preferably takes place between 250° and 500° C. on a catalyst of the alumina type containing an alkali or alkaline earth oxide. The process permits the unsubstituted or substituted thiophene to be obtained with high yields and high degrees of selectivity, exceeding 70%.
Inventors
- 👤 Joel Barrault
- 👤 Michel Guisnet
- 👤 Jacques Lucien
- 👤 Raymond Maurel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:18
CPC Classifications
C; C07; C07D; C07D333/00; C07D333/02; C07D333/04; C07D333/06; C07D333/08; C07D333/10; C07D333/50; C07D333/52; C07D333/54; C07D333/72
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
77 words
A method for preparing thiophenes, which comprises reacting in the presence of an alumina catalyst between 250° and 500° C. hydrogen sulfide with a compound selected from the group consisting of the unsaturated carbonyl and thiocarbonyl compounds represented by the formula ##STR11## where X is O or S while each of the symbols R, R', R" and R''' is hydrogen or lower alkyl, or ortho-tolualdehyde or phenyl-acetaldehyde, then condensing the reaction mixture and separating the thiophene formed.
Claim 2
Independent Claim
77 words
A method for preparing thiophenes, which comprises reacting in the presence of an alumina catalyst between 250° and 500° C. hydrogen sulfide with a compound selected from the group consisting of the unsaturated carbonyl and thiocarbonyl compounds represented by the formula ##STR11## where X is O or S while each of the symbols R, R', R" and R''' is hydrogen or lower alkyl, or ortho-tolualdehyde or phenyl-acetaldehyde, then condensing the reaction mixture and separating the thiophene formed.
Claim 3
Dependent Claim
19 words
Method according to claim 1 wherein the reaction is carried out at about 300° C. to about 400° C.
Claim 4
Dependent Claim
11 words
Method according to claim 1, wherein the compound selected is crotonaldehyde.
Claim 5
Dependent Claim
12 words
Method according to claim 1, wherein the compound selected is mesityl oxide.
Claim 6
Dependent Claim
12 words
Method according to claim 1, wherein the compound selected is methylethyl acrolein.
Claim 7
Dependent Claim
11 words
Method according to claim 1, wherein the compound selected is 3-penten-2-one.
Claim 8
Dependent Claim
11 words
Method according to claim 1, wherein the compound selected is 2-methyl-2-butenal.
Claim 9
Dependent Claim
11 words
Method according to claim 1, wherein the compound selected is 2-n.hexenal.
Claim 10
Dependent Claim
11 words
Method according to claim 1, wherein the compound selected is 2-ethyl-2-hexenal.
Claim 11
Dependent Claim
14 words
Method according to claim 1, wherein the alumina used as catalyst contains γ alumina.
Claim 12
Dependent Claim
38 words
Method according to claim 10, wherein the alumina is incorporated with 0.5 to 15% by weight of a compound selected from the group consisting of Na 2 O, K 2 O, Na 2 S and K 2 S.
Claim 13
Dependent Claim
25 words
Method according to claim 11, in which the catalyst has a specific area in the range of about 60 to about 350 m 2 /g.
Claim 14
Dependent Claim
20 words
Method according to claim 12, in which the reaction is carried out under a pressure of 1 to 10 bars.
Claim 15
Dependent Claim
24 words
Method according to claim 1, wherein the amount of hydrogen sulfide is about 2 to about 5 moles per mole of said selected compound.
Claim 16
Dependent Claim
24 words
Method according to claim 11, wherein the amount of hydrogen sulfide is about 2 to about 5 moles per mole of said selected compound.
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) | 1982-03-05 | 1982-09-04 | 1983-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-03-05 | 1986-09-04 | 1987-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-03-05 | 1990-09-04 | 1991-03-06 | $7700.00 | Window Closed / Lapsed |