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US4003937A
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Method for the preparation of ytterbium(III) beta-diketonates
Assignee: SnamProgetti SpA
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Filing: 1975-12-10
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Granted: 1977-01-18
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Expires: 1995-12-10
Abstract
Abstract A method is disclosed for the preparation of ytterbium(III) beta-diketonates, the improvement consisting in that the reaction between an ytterbium(III) halide and a chelating agent (such as acetylacetone, dibenzoylmethane and dipivaloylmethane for example) is caused to take place in an anhydrous medium and in the presence of gaseous ammonia, the ytterbium(III) halide being also anhydrous.
Inventors
- 👤 Pierpaolo Garibaldi
- 👤 Fausto Calderazzo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 19:38
CPC Classifications
C; C07; C07C; C07C45/00; C07C45/77; C07C49/00; C07C49/92
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
42 words
A method for the preparation of ytterbium (III) beta-diketonates comprising of reacting an anhydrous ytterbium (III) halide with a chelating agent selected from the group consisting of acetylacetone, dibenzoylmethane and dipivaloylmethane in the presence of gaseous ammonia and of a nonaqueous solvent.
Claim 2
Independent Claim
42 words
A method for the preparation of ytterbium (III) beta-diketonates comprising of reacting an anhydrous ytterbium (III) halide with a chelating agent selected from the group consisting of acetylacetone, dibenzoylmethane and dipivaloylmethane in the presence of gaseous ammonia and of a nonaqueous solvent.
Claim 3
Dependent Claim
27 words
A method for the preparation of ytterbium (III) chelates according to claim 1 characterized in that the nonaqueous solvent is selected from tetrahydrofuran, ethers, ketones and esters.
Claim 4
Dependent Claim
32 words
A method for the preparation of ytterbium (III) chelates as defined in claim 1 wherein the reaction is carried out at a temperature in the range from 20° C to 60° C.
Claim 5
Dependent Claim
20 words
A method for the preparation of ytterbium (III) chelates as defined in claim 1 wherein the chelating agent is acetylacetone.
Claim 6
Dependent Claim
20 words
A method for the preparation of ytterbium (III) chelates as defined in claim 1 wherein the chelating agent is dibenzoylmethane.
Claim 7
Dependent Claim
20 words
A method for the preparation of ytterbium (III) chelates as defined in claim 1 wherein the chelating agent is dipivaloylmethane.
References Cited (Backward Citations)
US3631081A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-01-18 | 1980-07-19 | 1981-01-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-01-18 | 1984-07-19 | 1985-01-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-01-18 | 1988-07-19 | 1989-01-18 | $7700.00 | Window Closed / Lapsed |