Patent US4036852A successfully refreshed from Google Patents.
US4036852A
Expired / Lapsed
US
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Optical resolution of phenyl-glycine amide
Assignee: Stamicarbon BV
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Filing: 1975-10-20
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Granted: 1977-07-19
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Expires: 1995-10-20
Abstract
Abstract The process of the invention is directed to separating a racemic mixture of L- and D-phenyl-glycine amide, by treatments of the racemate with an optically active form of 2-pyrrolidone-5-carboxylic acid.
Inventors
- 👤 Wilhelmus H. J. Boesten
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:29
CPC Classifications
C; C07; C07D; C07D207/00; C07D207/02; C07D207/18; C07D207/22; C07D207/24; C07D207/26; C07D207/273; C07D207/277; C07D207/28
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
82 words
A process for isolating an optically active form of phenyl-glycine amide, from racemic mixtures of the enantiomers of phenyl-glycine amide, comprising providing a racemic mixture of D- and L-phenyl-glycine amide and an optically active form of 2-pyrrolidone-5-carboxylic acid; treating said racemic mixture with the 2-pyrrolidone-5-carboxylic acid to form the corresponding salts of said optically active 2-pyrrolidone-5-carboxylic acid and said enantiomers; and separating from the mixture an optically active form of phenyl-glycine amide in the form of a salt of said 2-pyrrolidone-5-carboxylic acid.
Claim 2
Dependent Claim
82 words
A process for isolating an optically active form of phenyl-glycine amide, from racemic mixtures of the enantiomers of phenyl-glycine amide, comprising providing a racemic mixture of D- and L-phenyl-glycine amide and an optically active form of 2-pyrrolidone-5-carboxylic acid; treating said racemic mixture with the 2-pyrrolidone-5-carboxylic acid to form the corresponding salts of said optically active 2-pyrrolidone-5-carboxylic acid and said enantiomers; and separating from the mixture an optically active form of phenyl-glycine amide in the form of a salt of said 2-pyrrolidone-5-carboxylic acid.
Claim 3
Dependent Claim
46 words
Process according to claim 1, characterized in that the salt formation is effected in a liquid medium which is water; a water-miscible polar organic solvent containing 1 - 4 carbon atoms; or a mixture thereof, in which the diastereoisomeric salts are soluble to a different extent.
Claim 4
Dependent Claim
24 words
Process according to claim 2, characterized in that the liquid medium used is methanol, ethanol, isopropyl alcohol, acetone, dioxane, water, or a mixture thereof.
Claim 5
Dependent Claim
21 words
Process according to claim 2, wherein said step of treating is undertaken at a temperature ranging from 30° to 90° C.
Claim 6
Dependent Claim
20 words
Process according to claim 1, characterized in that 1 mole of 2-pyrrolidone-5-carboxylic acid is used per mole of DL-phenyl-glycine amide.
Claim 7
Dependent Claim
20 words
Process according to claim 1, characterized in that 0.5 mole of 2-pyrrolidone-5-carboxylic acid is used per mole of DL-phenyl-glycine amide.
Claim 8
Dependent Claim
29 words
Process according to claim 1, wherein the enantiomer which is not separated as a salt of the optically active 2-pyrrolidone-5-carboxylic acid is subsequently racemized by heating in a solvent.
Claim 9
Dependent Claim
12 words
Process according to claim 1, wherein 2-pyrrolidone-5-carboxylic acid is in the L-form.
Claim 10
Dependent Claim
9 words
D- and L-2-pyrrolidone-5-carboxylic salts of optically active phenyl-glycine amide.
Claim 11
Dependent Claim
9 words
D- and L-2-pyrrolidone-5-carboxylic salts of optically active phenyl-glycine amide.
References Cited (Backward Citations)
US2528267A
Cited
US2543345A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-07-18 | 1981-01-17 | 1981-07-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-18 | 1985-01-17 | 1985-07-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-18 | 1989-01-17 | 1989-07-19 | $7700.00 | Window Closed / Lapsed |