Patent EP0335517A2 successfully refreshed from Google Patents.
Patent US4374780A successfully refreshed from Google Patents.
US4374780A
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US
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Di-2,4,4'-trimethylpentylphosphinic acid and its preparation
Assignee: Cyanamid Canada Inc
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Filing: 1981-05-14
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Granted: 1983-02-22
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Expires: 2001-05-14
Abstract
Abstract Free radical addition of two moles of 2,4,4'-trimethylpentene-1 to 2,4,4'-trimethylpentylphosphine followed by the oxidation of the 2,4,4'-trimethylpentylphosphine with two moles of hydrogen peroxide is employed to prepare 2,4,4'-trimethylpentylphosphinic acid. The 2,4,4'-trimethylpentylphosphinic acid is useful as a cobalt extractant.
Inventors
- 👤 Allan J. Robertson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 13:54
CPC Classifications
C; C22; C22B; C22B3/00; C22B3/20; C22B3/26; C22B3/38; C22B3/384; C22B3/3842; C07; C07F; C07F9/00; C07F9/02; C07F9/28; C07F9/30; C07F9/301; C07F9/50; C07F9/5004; Y; Y02; Y02P; Y02P10/00; Y02P10/20; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/911; Y10S210/912
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
4 words
The compound di-2,4,4'-trimethylpentylphosphinic acid.
Claim 2
Dependent Claim
4 words
The compound di-2,4,4'-trimethylpentylphosphinic acid.
References Cited (Backward Citations)
US2957931A
Cited
US3052514A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-02-21 | 1986-08-23 | 1987-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-21 | 1990-08-23 | 1991-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-21 | 1994-08-23 | 1995-02-22 | $7700.00 | Window Closed / Lapsed |