US4542235A
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Method for producing an optically active 2,2-dimethylcyclopropanecarboxylic acid
Assignee: Sumitomo Chemical Co Ltd
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Filing: 1983-04-05
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Granted: 1985-09-17
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Expires: 2003-04-05
Abstract
Abstract A method for producing an optically active 2,2-dimethylcyclopropanecarboxylic acid useful as an intermediate for dehydropeptidase I inhibitors, medicines and agricultural chemicals, which comprises reacting an optically active diphenylethylamine represented by the formula, <IMAGE> wherein R1 and R2 are each a hydrogen atom or a lower alkyl group, with 2,2-dimethylcyclopropanecarboxylic acid in a solvent to achieve the optical purification of said acid.
Inventors
- 👤 Masayoshi Minai
- 👤 Tadashi Katsura
- 👤 Kazuhiko Hamada
- 👤 Gohfu Suzukamo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 00:22
CPC Classifications
C; C07; C07C; C07C51/00; C07C51/42; C07C51/487
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
52 words
A method for producing an optically active 2,2-dimethylcyclopropanecarboxylic acid which comprises reacting an optically active diphenylethylamine represented by the formula (I), ##STR3## wherein R 1 and R 2 are each a hydrogen atom or a lower alkyl group, with 2,2-dimethylcyclopropanecarboxylic acid in a solvent to achieve the optical purification of said acid.
Claim 2
Independent Claim
52 words
A method for producing an optically active 2,2-dimethylcyclopropanecarboxylic acid which comprises reacting an optically active diphenylethylamine represented by the formula (I), ##STR3## wherein R 1 and R 2 are each a hydrogen atom or a lower alkyl group, with 2,2-dimethylcyclopropanecarboxylic acid in a solvent to achieve the optical purification of said acid.
Claim 3
Dependent Claim
28 words
A method as described in claim 1, wherein said 2,2-dimethylcyclopropanecarboxylic acid is a one containing the d-form in excess, and said optically active 2,2-dimethylcyclopropanecarboxylic acid is d-2,2-dimethylcyclopropanecarboxylic acid.
Claim 4
Dependent Claim
28 words
A method as described in claim 1, wherein said 2,2-dimethylcyclopropanecarboxylic acid is a one containing the l-form in excess, and said optically active 2,2-dimethylcyclopropanecarboxylic acid is l-2,2-dimethylcyclopropanecarboxylic acid.
Claim 5
Dependent Claim
21 words
A method as described in claim 2, wherein the optical excess rate of said 2,2-dimethylcyclopropanecarboxylic acid is not less than 30%.
Claim 6
Dependent Claim
25 words
A method as described in claim 1, wherein said optically active diphenylethylamine is either of d- or l-α-phenyl-β-(p-tolyl)ethylamine, d- or l-α-(p-tolyl)-β-phenylethylamine or d- or l-α-phenyl-β-phenylethylamine.
Claim 7
Dependent Claim
30 words
A method as described in claim 1, wherein the amount of the optically active diphenylethylamine used is 0.3 to 1.2 times by mole based on 2,2-dimethylcyclopropanecarboxylic acid, a starting material.
Claim 8
Dependent Claim
21 words
A method as described in claim 3, wherein the optical excess rate of said 2,2-dimethylcyclopropanecarboxylic acid is not less than 30%.
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) | 1988-09-16 | 1989-03-18 | 1989-09-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-16 | 1993-03-18 | 1993-09-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-16 | 1997-03-18 | 1997-09-17 | $7700.00 | Window Closed / Lapsed |