US3787482A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of synthesizing hydrazine compounds carboxylic acids
Assignee: Individual
•
Filing: 1970-02-20
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Granted: 1974-01-22
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Expires: 1990-02-20
Abstract
Abstract A PROCESS FOR THE PREPARATION OF HYDRAZIDES OF AMINO POLYCARBOXYLIC ACIDS, PARTICULARLY DIHYDRAZIDES, WHEREIN THE ACID IS ESTERIFIED WITH A LOW BOILING ALCOHOL IN STRONGLY ACIDIC MEDIA AND THE REACTION MIXTURE IS THEN MADE TO REACT WITH AN INCREASED AMOUNT OF THE AMINO POLYCARBOXYLIC ACID TO FORM A REACTIVE MATERIAL IN SOLUTION, WHEREUPON THE REACTION PRODUCT ESTER-ACID MIXTURE IS REACTED WITH A HYDRAZINE IN APPROPRIATE MOLAR AMOUNT TO FORM MONO-, DI-, TRI-, ETC., UP TO HYDRAZIDE MOIETY LESS THAN THE COMPLETELY CONVERTED HYDRAZIDE. THE CARBOXYLATE MOIETIES NOT CONVERTED TO HYDRAZIDES ARE CONVERTED TO HYDRAZINIUM SALTS. THE RESULTING COMPOUNDS ARE USEFUL AS CHELATING AGENTS.
Inventors
- 👤 F Bersworth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:42
CPC Classifications
—
Claims Analysis
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-21 | 1977-07-23 | 1978-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-21 | 1981-07-23 | 1982-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-21 | 1985-07-23 | 1986-01-22 | $7700.00 | Window Closed / Lapsed |