US2509938A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing fused cyclic derivatives of thiophene
Assignee: Texaco Inc
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Filing: 1948-05-06
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Granted: 1950-05-30
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Expires: 1968-05-06
Abstract
No abstract record available.
Inventors
- 👤 John A Patterson
- 👤 Charles H Culnane
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 12:26
CPC Classifications
C; C07; C07D; C07D333/00; C07D333/50; C07D333/76
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
60 words
A PROCESS FOR PREPARING FUSED CYCLIC DERIVATIVES OF THIOPHENE WHICH COMPRISES REACTING A CYCLIC COMPOUND HAVING A GENERIC FORMULA R1-R2, WHEREIN R1 AND REPRESENT CYCLIC NUCLEI CONTAINING A HYDROGEN-SUBSTITUTED CARBON ATOM ADJACENT TO THE INTERCYCLIC BOND WITH HYDROGEN SULFIDE IN THE VAPOR PHASE IN THE PRESENCE OF A SOLID PARTICULATE CONTACT CATALYST AT AN ELEVATED TEMPERATURE OF AT LEAST 700*F.
Claim 2
Dependent Claim
60 words
A PROCESS FOR PREPARING FUSED CYCLIC DERIVATIVES OF THIOPHENE WHICH COMPRISES REACTING A CYCLIC COMPOUND HAVING A GENERIC FORMULA R1-R2, WHEREIN R1 AND REPRESENT CYCLIC NUCLEI CONTAINING A HYDROGEN-SUBSTITUTED CARBON ATOM ADJACENT TO THE INTERCYCLIC BOND WITH HYDROGEN SULFIDE IN THE VAPOR PHASE IN THE PRESENCE OF A SOLID PARTICULATE CONTACT CATALYST AT AN ELEVATED TEMPERATURE OF AT LEAST 700*F.
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) | 1953-05-29 | 1953-11-28 | 1954-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-05-29 | 1957-11-28 | 1958-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-05-29 | 1961-11-28 | 1962-05-30 | $7700.00 | Window Closed / Lapsed |