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Patent US2540307A successfully refreshed from Google Patents.
US2540307A
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3, 4-diethoxymandelic acid and process for preparing same
Assignee: Merck and Co Inc
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Filing: 1947-12-09
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Granted: 1951-02-06
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Expires: 1967-12-09
Abstract
No abstract record available.
Inventors
- 👤 Weijlard John
- 👤 Tishler Max
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:37
CPC Classifications
C; C07; C07C; C07C59/00; C07C59/40; C07C59/58; C07C59/64
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
47 words
THE PROCESS THAT COMPRISES REACTING 3,4-DIETHOXYMANDELIC ACID NITRILE WITH ANHYDROUS HYDROCHLORIC ACID IN AN ABSOLUTE LOWER ALIPHATIC ALCOHOL MEDIUM AT ROOM TEMPERATURE FOR APPROXIMATELY FORTY TO ONE-HUNDRED HOURS, RECOVERING THE 3,4-DIETHOXYMANDELIC ACID ALKYL ESTERS THUS FORMED AND HYDROLYZING THE LATTER COMPOUND AT ROOM TEMPERATURE TO 3,4-DIETHOXYMANDELIC ACID.
Claim 2
Dependent Claim
47 words
THE PROCESS THAT COMPRISES REACTING 3,4-DIETHOXYMANDELIC ACID NITRILE WITH ANHYDROUS HYDROCHLORIC ACID IN AN ABSOLUTE LOWER ALIPHATIC ALCOHOL MEDIUM AT ROOM TEMPERATURE FOR APPROXIMATELY FORTY TO ONE-HUNDRED HOURS, RECOVERING THE 3,4-DIETHOXYMANDELIC ACID ALKYL ESTERS THUS FORMED AND HYDROLYZING THE LATTER COMPOUND AT ROOM TEMPERATURE TO 3,4-DIETHOXYMANDELIC ACID.
References Cited (Backward Citations)
GB189514886A
Cited
US895316A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-02-05 | 1954-08-07 | 1955-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-02-05 | 1958-08-07 | 1959-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-02-05 | 1962-08-07 | 1963-02-06 | $7700.00 | Window Closed / Lapsed |