US3203989A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the production of phenylhydrazine hydrochloride
Assignee: Hoechst AG
•
Filing: 1962-08-14
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Granted: 1965-08-31
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Expires: 1982-08-14
Abstract
No abstract record available.
Inventors
- 👤 Hupfer Heinz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:30
CPC Classifications
C; C07; C07C; C07C241/00; C07C241/02; C07C243/00; C07C243/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
106 words
A PROCESS FOR PREPARING PHENYLHYDRAZINE HYDROCHLORIDE WHICH COMPRISES A) RAPIDLY AND INTIMATELY MIXING, AT A TEMPERATURE WITHIN THE RANGE OF 0 TO 30* C., PHENYLDIAZONIUM CHLORIDE WITH AN AMOUNT OF A MIXTURE OF SODIUM SUFITE AND SODIUM BISULFITE SUFFICIENT TO GIVE THE RESULTING REDUCTION MIXTURE, WHEN HEATED TO 80 TO 85* C., A PH OF 5.0 TO 7.0, B) HEATING SAID REDUCTION MIXTURE TO A TEMPERATURE WITHIN THE RANGE OF 80 TO 85* C. TO REDUCE THE PHENYLDIAZONIUM CHLORIDE TO PHENYLHYDRAZINE HYDROCHLORIDE, C) ADDING CONCENTRATE HYDROCHLORIC ACID THERETO TO PRECIPITATE THE PHENYLHYDRAZINE HYDROCHLORIDE SO FORMED, AND D) ISOLATING THE PRECIPITATED PHENYLHYDRAZINE HYDROCHLORIDE FROM THE REACTION MIXTURE.
Claim 2
Dependent Claim
106 words
A PROCESS FOR PREPARING PHENYLHYDRAZINE HYDROCHLORIDE WHICH COMPRISES A) RAPIDLY AND INTIMATELY MIXING, AT A TEMPERATURE WITHIN THE RANGE OF 0 TO 30* C., PHENYLDIAZONIUM CHLORIDE WITH AN AMOUNT OF A MIXTURE OF SODIUM SUFITE AND SODIUM BISULFITE SUFFICIENT TO GIVE THE RESULTING REDUCTION MIXTURE, WHEN HEATED TO 80 TO 85* C., A PH OF 5.0 TO 7.0, B) HEATING SAID REDUCTION MIXTURE TO A TEMPERATURE WITHIN THE RANGE OF 80 TO 85* C. TO REDUCE THE PHENYLDIAZONIUM CHLORIDE TO PHENYLHYDRAZINE HYDROCHLORIDE, C) ADDING CONCENTRATE HYDROCHLORIC ACID THERETO TO PRECIPITATE THE PHENYLHYDRAZINE HYDROCHLORIDE SO FORMED, AND D) ISOLATING THE PRECIPITATED PHENYLHYDRAZINE HYDROCHLORIDE FROM THE REACTION MIXTURE.
References Cited (Backward Citations)
US2013394A
Cited
GB758395A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-08-30 | 1969-03-01 | 1969-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-08-30 | 1973-03-01 | 1973-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-08-30 | 1977-03-01 | 1977-08-31 | $7700.00 | Window Closed / Lapsed |