Patent US3338919A successfully refreshed from Google Patents.
US3338919A
Expired / Lapsed
US
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Process for producing acid imide derivatives
Assignee: Imperial Chemical Industries Ltd
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Filing: 1964-10-19
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Granted: 1967-08-29
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Expires: 1984-10-19
Abstract
No abstract record available.
Inventors
- 👤 Nield Eric
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:53
CPC Classifications
C; C07; C07D; C07D207/00; C07D207/02; C07D207/44; C07D207/444; C07D207/448; B; B01; B01J; B01J27/00; B01J27/14; B01J27/16; C07D207/452; C08; C08F; C08F2/00; C08F2/38
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
164 words
A PROCESS FOR THE CYCLISATION OF AN AMIC ACID SELECTED FROM THE GROUP CONSISTING OF (A) A,B-ETHYLENICALLY UNSATURATED CIS-A,B-AMIC ACIDS WHICH ARE FREE OF ATOMIC GROUPS WHICH ARE BASIC IN CHARACTER AND (B) THE MONO N-SUBSTITUTED DERIVATIVES THEREOF WHICH ARE FREE OF GROUPS WHICH ARE BASIC IN CHARCTER AND HAVE THE N-SUBSTITUENT LINKED TO THE NITROGEN ATOM BY A CARBON-NITROGEN BOND, SAID PROCESS COMPRISING REFLUXING THE AMIC ACID IS AN EXCESS OF AN INERT ORGANIC DILUENT HAVING A BOILING POINT LYING WITHIN THE RANGE 80 TO 200*C. WITH AN ACIDIC CATALYST SELECTED FROM THE GROUP CONSISTING OF SULPHUR TRIOXIDE, SULPHURIC ACID, CHLOROSULPHONIC ACID, POLYPHOSPHORIC ACIDS, PYROPHOSPHORIC ACID, PHOSPHOROUS ACIDS HAVING THE STRUCTURES HOPO, HOPO2, (HO)3P, (HO)3PO, HPO(OH)2, HP(OH)2, H2POH AND H2PO.OH, ORGANIC SULPHONIC ACIDS AND ORGANO-PHOSPHORUS, ACIDS, THE AMOUND OF THE CATALYST BEING 0.01 TO 20% BY WEIGHT OF THE TOTAL AMOUNT OF THE AMIC ACID EMPLOYED, AND DISTILLING OFF FROM THE REACTION MIXTURE DURING THE CYCLISATION PROCESS THE WATER FORMED BY THE REACTION.
Claim 2
Dependent Claim
164 words
A PROCESS FOR THE CYCLISATION OF AN AMIC ACID SELECTED FROM THE GROUP CONSISTING OF (A) A,B-ETHYLENICALLY UNSATURATED CIS-A,B-AMIC ACIDS WHICH ARE FREE OF ATOMIC GROUPS WHICH ARE BASIC IN CHARACTER AND (B) THE MONO N-SUBSTITUTED DERIVATIVES THEREOF WHICH ARE FREE OF GROUPS WHICH ARE BASIC IN CHARCTER AND HAVE THE N-SUBSTITUENT LINKED TO THE NITROGEN ATOM BY A CARBON-NITROGEN BOND, SAID PROCESS COMPRISING REFLUXING THE AMIC ACID IS AN EXCESS OF AN INERT ORGANIC DILUENT HAVING A BOILING POINT LYING WITHIN THE RANGE 80 TO 200*C. WITH AN ACIDIC CATALYST SELECTED FROM THE GROUP CONSISTING OF SULPHUR TRIOXIDE, SULPHURIC ACID, CHLOROSULPHONIC ACID, POLYPHOSPHORIC ACIDS, PYROPHOSPHORIC ACID, PHOSPHOROUS ACIDS HAVING THE STRUCTURES HOPO, HOPO2, (HO)3P, (HO)3PO, HPO(OH)2, HP(OH)2, H2POH AND H2PO.OH, ORGANIC SULPHONIC ACIDS AND ORGANO-PHOSPHORUS, ACIDS, THE AMOUND OF THE CATALYST BEING 0.01 TO 20% BY WEIGHT OF THE TOTAL AMOUNT OF THE AMIC ACID EMPLOYED, AND DISTILLING OFF FROM THE REACTION MIXTURE DURING THE CYCLISATION PROCESS THE WATER FORMED BY THE REACTION.
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) | 1970-08-28 | 1971-02-27 | 1971-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-08-28 | 1975-02-27 | 1975-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-08-28 | 1979-02-27 | 1979-08-29 | $7700.00 | Window Closed / Lapsed |