Patent US4093653A successfully refreshed from Google Patents.
US4093653A
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Process for the preparation of optically active phenyl glycine amide
Assignee: DSM BV
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Filing: 1976-12-08
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Granted: 1978-06-06
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Expires: 1996-12-08
Abstract
Abstract The invention is directed to a process for the separation of L-phenyl glycine amide from D-phenyl glycine amide by resolving a mixture containing the two optically active antipodes with an optically active acid, and racemizing the undesired antipode in the presence of a ketone and the optically active acid.
Inventors
- 👤 Wilhelmus H. J. Boesten
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 08:28
CPC Classifications
C; C07; C07B; C07B57/00
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
24 words
A process for isolating an optically active form of phenyl glycine amide, from a mixture of D- and L-phenyl glycine amide, consisting essentially of:
Claim 2
Dependent Claim
24 words
A process for isolating an optically active form of phenyl glycine amide, from a mixture of D- and L-phenyl glycine amide, consisting essentially of:
Claim 3
Dependent Claim
69 words
preparing a mixture of D- and L-phenyl glycine amide and an optically active acid of the class consisting of 2-pyrrolidone-5-carboxylic acid and N-acetyl phenylglycine; precipitating one antipode as diastereoisomer salt from a solution of said mixture; and racemizing in a solvent the other antipode from the mixture in the presence of a ketone selected from the class consisting of acetone, methylethyl ketone and cyclohexanone and said optically active acid.
Claim 4
Dependent Claim
69 words
preparing a mixture of D- and L-phenyl glycine amide and an optically active acid of the class consisting of 2-pyrrolidone-5-carboxylic acid and N-acetyl phenylglycine; precipitating one antipode as diastereoisomer salt from a solution of said mixture; and racemizing in a solvent the other antipode from the mixture in the presence of a ketone selected from the class consisting of acetone, methylethyl ketone and cyclohexanone and said optically active acid.
Claim 5
Dependent Claim
15 words
The process according to claim 1 wherein said optically active acid is N-acetyl phenyl glycine.
Claim 6
Dependent Claim
14 words
The process according to claim 1 wherein said optically active acid is 2-pyrrolidone-5-carboxylic acid.
Claim 7
Dependent Claim
25 words
The process according to claim 1 wherein said optically active acid is present in a quantity equivalent to the mixture of phenyl glycine amides present.
Claim 8
Dependent Claim
15 words
The process according to claim 2 wherein said optically active acid is L-N-acetyl phenyl glycine.
Claim 9
Dependent Claim
15 words
The process according to claim 2 wherein said optically active acid is D-N-acetyl phenyl glycine.
Claim 10
Dependent Claim
25 words
The process according to claim 1, wherein the racemization is carried out in the presence of a solvent in which the desired diastereoisomer salt precipitates.
Claim 11
Dependent Claim
27 words
The process according to claim 1 wherein the quantity of said optically active acid is in excess of equivalence to the mixture of phenyl glycine amides present.
Claim 12
Dependent Claim
17 words
The process according to claim 1 wherein said diastereoisomer separated from said mixture is separated by filtration.
Claim 13
Dependent Claim
25 words
The process according to claim 1 wherein said ketone is present in an amount of 0.1 mole of ketone per mole of phenyl glycine amide.
Claim 14
Dependent Claim
20 words
The process of claim 1 wherein said racemization treatment is carried out at a temperature between 50° and 100° C.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-06-05 | 1981-12-05 | 1982-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-06-05 | 1985-12-05 | 1986-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-06-05 | 1989-12-05 | 1990-06-06 | $7700.00 | Window Closed / Lapsed |