US4130566A
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Process for producing 5-carboxy-2-acetylthiophene
Assignee: Sumitomo Chemical Co Ltd
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Filing: 1977-10-28
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Granted: 1978-12-19
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Expires: 1997-10-28
Abstract
Abstract 5-Carboxy-2-acetylthiophene, which is useful as an intermediate for the production of a therapeutic agent, can be prepared in a high yield by the selective oxidation of 5-acetyl-2-thienylacetic acid or its derivative with a particularly selected oxidizing agent, i.e. chromic anhydride complex, dichromate or hypohalite.
Inventors
- 👤 Toshihiko Hibino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:19
CPC Classifications
C; C07; C07C; C07C255/00; A; A61; A61K; A61K31/00; A61K31/33; A61K31/395; A61K31/41; A61K31/425; A61K9/00; A61K9/48; A61P; A61P9/00; A61P9/08; A61P9/12; C07C29/00; C07C29/62; C07D; C07D277/00; C07D277/02; C07D277/08; C07D277/12; C07D277/14; C07D309/00; C07D309/02; C07D309/08; C07D309/10; C07D309/12; C07D317/00; C07D317/08; C07D317/10; C07D317/14; C07D317/16; C07D317/30; C07D333/00; C07D333/02; C07D333/04; C07D333/06; C07D333/24; C07D333/26; C07D333/38; C07B; C07B2200/00; C07B2200/09; C07C2601/00; C07C2601/12; C07C2601/14
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
53 words
A process for producing 5-carboxy-2-acetylthiophene which comprises oxidizing a compound of the formula ##STR6## wherein X is a conventional carbonyl-protecting group and R is a conventional ester residue, with a hypohalite in a mixture of water and an alcohol at a temperature from 0° to 60° C., and then removing the carbonyl-protecting group.
Claim 2
Dependent Claim
53 words
A process for producing 5-carboxy-2-acetylthiophene which comprises oxidizing a compound of the formula ##STR6## wherein X is a conventional carbonyl-protecting group and R is a conventional ester residue, with a hypohalite in a mixture of water and an alcohol at a temperature from 0° to 60° C., and then removing the carbonyl-protecting group.
Claim 3
Dependent Claim
62 words
A process for producing 5-carboxy-2-acetylthiophene which comprises oxidizing a compound of the formula ##STR7## wherein X is a carbonyl oxygen protected with a ketal, hemithioketal, dithioketal, thiazolidine, imidazolidine or oxazolidine and R is lower alkyl or phenyl, with a hypohalite in a mixture of water and an alcohol at a temperature from 0° to 60° C., and then removing the protecting group.
Claim 4
Dependent Claim
62 words
A process for producing 5-carboxy-2-acetylthiophene which comprises oxidizing a compound of the formula ##STR7## wherein X is a carbonyl oxygen protected with a ketal, hemithioketal, dithioketal, thiazolidine, imidazolidine or oxazolidine and R is lower alkyl or phenyl, with a hypohalite in a mixture of water and an alcohol at a temperature from 0° to 60° C., and then removing the protecting group.
Claim 5
Dependent Claim
12 words
The process according to claim 2, wherein the hypohalite is a hypochlorite.
Claim 6
Dependent Claim
19 words
The process according to claim 2, wherein the hypohalite is sodium hypochlorite, sodium hypobromite, potassium hypochlorite or potassium hypobromite.
Claim 7
Dependent Claim
38 words
A process for producing 5-carboxy-2-acetylthiophene which comprises oxidizing 5-acetyl-2-thienylacetic acid with a chromic anhydride-acetic acid complex, a chromic anhydride-pyridine complex, a chromic anhydride-dimethylformamide complex or a dichromate, in a solvent at a temperature from 0° to 100° C.
Claim 8
Dependent Claim
38 words
A process for producing 5-carboxy-2-acetylthiophene which comprises oxidizing 5-acetyl-2-thienylacetic acid with a chromic anhydride-acetic acid complex, a chromic anhydride-pyridine complex, a chromic anhydride-dimethylformamide complex or a dichromate, in a solvent at a temperature from 0° to 100° C.
Claim 9
Dependent Claim
15 words
The process according to claim 5, wherein said dichromate is potassium dichromate or sodium dichromate.
Claim 10
Dependent Claim
35 words
The process according to claim 5, wherein said oxidation is carried out with a chromic anhydride-acetic acid complex or a chromic anhydride-pyridine complex in acetic acid, acetic anhydride, acetic acid-acetic anhydride mixed solvent, or pyridine.
Claim 11
Dependent Claim
24 words
The process according to claim 5, wherein said oxidation is carried out with a dichromate in acetic acid, acetic anhydride or a mixture thereof.
Claim 12
Dependent Claim
15 words
The process according to claim 8, wherein said dichromate is potassium dichromate or sodium dichromate.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-12-18 | 1982-06-19 | 1982-12-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-12-18 | 1986-06-19 | 1986-12-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-12-18 | 1990-06-19 | 1990-12-19 | $7700.00 | Window Closed / Lapsed |